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Dancing David
1st March 2008, 08:04 AM
On the z-pinch and sunspots as examples of z-pinch phenomena.

In other threads much of the electric sun model has been discussed at some lenth and confusion of subject matter. A certain poster has made two claims in seperate threads, one that sunspots are where Birkeland currents enter the sun. And in another that sunspots are an example of possible z-pinch effect and that this provides the energy for the sun. Although the notion that the corona is heated by the z-pinch seems to have some merit I want to address this claim.

I am sure that the temperature of sunspots may become an issue of debate , yet two sources say the following:

Sunspots are darker than the rest of the visible solar surface because they are cooler: Most of the visible surface of the Sun has a temperature of about 9700 F (5400 C), but in a big sunspot the temperature can drop to about 7200 F (4000 C). Sunspots come in sizes between about 1500 miles (2500 km) and about 30,000 miles (50,000 km), so they are much smaller than the Sun itself, which has a diameter of 865,000 miles (1,392,000 km).

http://solar.physics.montana.edu/YPOP/Classroom/Lessons/Sunspots/

The photosphere has a temperature of about 5500 degrees Celsius and a typical sunspot has a temperature about 3900 degrees Celsius.

So if the light given off by the sunspot is an indication of it’s temperature then a sunspot might be considered to be at a temperature ~5700 K,~4100K or ~4300 K

Trying to find a rough estimate of the temperatures needed for a z-pinch scenario to occur I found the following.

http://aps.arxiv.org/ftp/arxiv/papers/0802/0802.1883.pdf

Some of the earliest attempts to realize controlled nuclear fusion were based on the z-pinch, where a large current is discharged through a column of deuterium-tritium (DT) gas, to compress and heat the DT to the ignition temperature of 10 keV.

But I am not sure how to translate keV to conventional temperature although I know it is a measure of energy.

So here I found another source for possible temperatures for hydrogen fusion to occur.

http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/coubar.html#c2

Deuterium-deuterium fusion : 40 x 10^7 K

Deuterium-tritium fusion: 4.5 x 10^7 K

In the sun, the proton-proton cycle of fusion is presumed to proceed at a much lower temperature because of the extremely high density and high population of particles.

Interior of the sun, proton cycle: 1.5 x 10^7 K

And so that would appear to me that he temperature for fusion could be:

- 40x10000000 or 400,000,000
- 4.5x10000000 or 45,000,000
- 1.5x 10000000 or 15,000,000

Or at least I am assuming that the numbers are in degrees Kelvin, but 400,000,000 sounds a whole lot higher that the three million usually given for fusion, so it could be they are in keV.

I don’t think they are because then the numbers would go even higher.

So……

If the temperature required at the center of the sun is 1.5x10^7 K and that is because of the density of the material, how are we going to get a z-pinch to fuse at the temperature of ~4000K?

Of course I am sure I missing something here.

Ziggurat
1st March 2008, 10:27 AM
But I am not sure how to translate keV to conventional temperature although I know it is a measure of energy.

Divide the energy by Boltzmann's constant (http://en.wikipedia.org/wiki/Boltzmann_constant) kB = 8.6x10-5 eV/K to get the temperature. In the case of 10 keV, that gives us (10/8.6)x108 K = 116 million deg. K. Of course, these are all only ballpark figures: for a thermally driven process, the rate as a function of temperature is not a step function.

Dancing David
1st March 2008, 12:03 PM
Thanks,

that is still a whole bunch higher than ~4,000 K.

Zeuzzz
1st March 2008, 01:03 PM
My personal thoughts on sunspots is that they are areas where the normal outward travelling solar wind inverts, and you get small currents of particles streaming back into to the sun, against the predominant direction. This may explain the temparature minimum, as the particles are entering from the cooler region just above the photosphere, and they would also shield that area from the heat being generated below.

In terms of why sunspots are black, i'm going to pass on that one for now, i have not so far seen a definitve reson for this. Surprising really, any process that changes the electron transitions and the subsequent wavelengths of the light emitted would be a viable one.

Complexity
2nd March 2008, 08:59 AM
My personal thoughts on sunspots is ...

Not of any interest to me whatsoever.

The Man
2nd March 2008, 09:35 AM
The real problem with direct Z-pinched fusion is that the experimental evidence “indicated that magneto-hydrodynamic instabilities prevented the pinched plasma from reaching the required plasma temperatures and densities for fusion in equilibrium”. If those instabilities could not be overcome under controlled laboratory conditions, I find it highly unlikely that conditions would be any more stable or controlled in such a chaotic environment as the surface of the Sun. Z-pinches do work just fine as X-ray sources for indirect-drive Inertial Confinement Fusion. However once again due the extreme controlled conditions require (specifically the symmetry of the incident radiation flux), I find that even indirect-drive Inertial Confinement Fusion from a solar surface Z-pinched plasma is highly unlikely in such a chaotic environment as the surface of the Sun.

http://www.iaea.org/programmes/ripc/physics/fec1998/pdf/ov3_4.pdf

BeAChooser
2nd March 2008, 11:38 AM
A certain poster has made two claims in seperate threads, one that sunspots are where Birkeland currents enter the sun. And in another that sunspots are an example of possible z-pinch effect and that this provides the energy for the sun.

David, once again you misrepresent what I actually said. I'm not certain whether I ever linked something that made the first claim. I suppose it's possible. But I certainly didn't make the second claim. I drew your attention to an image that happens to have a sunspot in it but it also has something else ... an bright many filamented event in the vicinity but not directly over the sunspot. And that might be a z-pinch. I made every effort to get you to look at that something else but apparently your blinders made it impossible for you to see anything but the sunspot. :rolleyes:

BeAChooser
2nd March 2008, 11:43 AM
And in another that sunspots are an example of possible z-pinch effect and that this provides the energy for the sun.

Furthermore, I never once claimed that z-pinches provide the energy for the sun. You asked what could produce heavy elements in the electric sun model and I pointed you to z-pinches which appear to reach both the temperatures and densities needed to do that according to current mainstream theory. I never once said or implied that the energy from the sun was coming from z-pinches. So how you managed to get it into the dark matter inside your head that I did ... is puzzling. :D

robinson
2nd March 2008, 12:10 PM
Sometimes people just make stuff up. It's fun!

Until somebody points out you just made it up.

Reality Check
2nd March 2008, 01:37 PM
Wikipedia has a good article on sunspots where is is clearly stated that they are only dark in contrast to the surrounding material. A temperature of 4000-4500 K means that they are brighter than an electric arc.

Zeuzzz
2nd March 2008, 01:46 PM
Originally Posted by Zeuzzz
My personal thoughts on sunspots is ...

Not of any interest to me whatsoever.

Well shut up then. Did you really need to post that comment?

I see no derogatory comments aimed at you. Whats your problem, really?

Reality Check
2nd March 2008, 01:49 PM
Hi BeAChooser
The standard solar model states that all of the energy from the Sun is produced by fusion. The model then gives a calculation of the rate of production of neutrinos. Experiments here on Earth have verified that the Sun produces this neutrino flux.
What is the prediction from your model of the neutrino flux and how does it match with the experiment?

Dancing David
2nd March 2008, 02:10 PM
David, once again you misrepresent what I actually said. I'm not certain whether I ever linked something that made the first claim. I suppose it's possible. But I certainly didn't make the second claim. I drew your attention to an image that happens to have a sunspot in it but it also has something else ... an bright many filamented event in the vicinity but not directly over the sunspot. And that might be a z-pinch. I made every effort to get you to look at that something else but apparently your blinders made it impossible for you to see anything but the sunspot. :rolleyes:
Roll your eyes, i asked where there was evidence of a z-pinch on the surface of the sun and you posted the picture. Perhaps your opaque answer is too opaque.

Ever the con man, your answer was the picture with no explantion, just as when I posisted that if Birkeland currents were enetering the sun it would effect the corona and you posted a picture of a sunspot. Since you won't explain youself it isn't my blinders but your lack of effort in explanation.

Here is the post with your cryptic answer and lack of explanation:
http://forums.randi.org/showpost.php?p=3481581&postcount=517

But a z-pinch near the solar surface can produce metals and other elements and alter the ratio of hydrogen and helium in the near surface atmosphere. In an electric star, heavy element abundances would not be fixed but would be created in the outer layers by the high-energy discharges. Red giants could simply be stars that once were subject to higher electric current density (producing lots of metals and converting H to He) which are now, for whatever reason, traveling through a region with lower current density.

So where is the evidence that the surface of the sun has the temperature to support a z-pinch BAC?

So where does the energy come from to causes the sun to shine BAC?

Please do answer, tell us that is Birkeland currents or whatever you think it is.

Your lack of explanation is telling, you don't understand your own theories so you fail to explain them. But then perhaps you are better saying less and just not explaining anything.

Dancing David
2nd March 2008, 02:13 PM
Furthermore, I never once claimed that z-pinches provide the energy for the sun. You asked what could produce heavy elements in the electric sun model and I pointed you to z-pinches which appear to reach both the temperatures and densities needed to do that according to current mainstream theory. I never once said or implied that the energy from the sun was coming from z-pinches. So how you managed to get it into the dark matter inside your head that I did ... is puzzling. :D

Uh huh, so what provides the power that illuminates the sun BAC, perhaps the problem is that you spew so much nonsense you don't remember what you post.

The z-pinch you mentioned in answer to my question was a galactic jet if I recall correctly or was it a supernova?

You can't answer direct questions because you don't understand that which you try to present.

1. What would the field strenth of a magnetic field need to be to move the sun and other stars as per the Perrat model?

2. What provides the energy which power the sun BAC, where is the sun does it occur?

3. How does plasma cosmology explain the general proportions of H, He and Li?

4. How do iron whiskers produce a black body spectrum?

These questions still await your answer as does the sampling error of Arp and statistics of QSOs.

Reality Check
2nd March 2008, 04:04 PM
Hi Dancing David
One thing to remember about z-pinches is that they are another magnetic mechanism to produce conventional fusion. The other methods include gravitation (as in stars) and inertia (as in hydrogen bombs). This means that the temperatures that we are talk about are those of normal fusion, i.e. millions of Kelvin.

BeAChooser
If there are z-pinches occurring anywhere on the surface of the Sun then we have to wonder why astronomers have never noticed these massively hot (million K!) spots. Why have the many satellites observing the Sun not recorded them?
Can you tell us the answer?

Dancing David
2nd March 2008, 06:00 PM
Hi Dancing David
One thing to remember about z-pinches is that they are another magnetic mechanism to produce conventional fusion. The other methods include gravitation (as in stars) and inertia (as in hydrogen bombs). This means that the temperatures that we are talk about are those of normal fusion, i.e. millions of Kelvin.

I am aware of that, I am trying to maintain composure and try to have a discussion with BAC, some days I don't respond as well as I should. Wisely or not I am trying to get BAC to actually discuss issues rather than post and run or spin.

I anticipate a deafening silence or discussion of coronal events and snippetts of pop science and journal articles.

BeAChooser
2nd March 2008, 07:52 PM
Experiments here on Earth have verified that the Sun produces this neutrino flux.

Are you sure? The standard solar model says the nuclear reaction taking place inside the Sun produces electron neutrinos. Although the total neutrino flux may be close to the required level, the number electron neutrinos can only be inferred as being sufficient if they ‘oscillate’ into other types of neutrinos. Seems to me the only way the Sudbury Neutrino Observatory (SNO) could have determined a change in type with any certainty is by detecting the type of neutrinos at both ends of the pipe running from the sun to the earth. They didn't do that. They detected neutrinos only at the earth's end. When Sudbury Neutrino Observatory (SNO) declared that “the SNO detector has the capability to determine whether solar neutrinos are changing their type en route to Earth”, I think they were somewhat dishonest ... or perhaps as Ziggurat likes to say, "sloppy".

Fermilab’s MiniBooNE, a very recent neutrino experiment (albeit not the same kind of neutrinos), stated (http://cosmicvariance.com/2007/04/11/miniboone-neutrino-result-guest-blog-from-heather-ray/ ) concluded "The MiniBooNE neutrino data set agrees with the no neutrino oscillation hypothesis, in the range of reconstructed neutrino energy from 475 MeV to 3 GeV. The probability that MiniBooNE and LSND both are due to two-neutrino oscillations is only 2%.”

And I don't know of any more recent experiment that actually proves neutrinos oscillate. Do you?

sol invictus
2nd March 2008, 08:06 PM
Hi BeAChooser
The standard solar model states that all of the energy from the Sun is produced by fusion. The model then gives a calculation of the rate of production of neutrinos. Experiments here on Earth have verified that the Sun produces this neutrino flux.
What is the prediction from your model of the neutrino flux and how does it match with the experiment?

One of the beautiful things about that is that physicists (way back in 1969) were able to predict that neutrinos oscillate based on an observed deficit in the quantity of solar electron neutrinos. That prediction was treated skeptically for years (people were more inclined to believe there was an error either in the calculations or in the experiment, which is very difficult) until it was experimentally confirmed by several experiments recently, using neutrinos generated by both nuclear reactors and particle accelerators, as well as observations of solar neutrinos that were able to detect more than just electron neutrinos.

Here's a nice description of much of that:

http://nobelprize.org/nobel_prizes/physics/articles/bahcall/

Acleron
2nd March 2008, 08:13 PM
Fermilab’s MiniBooNE, a very recent neutrino experiment (albeit not the same kind of neutrinos), stated (http://cosmicvariance.com/2007/04/11/miniboone-neutrino-result-guest-blog-from-heather-ray/ ) concluded "The MiniBooNE neutrino data set agrees with the no neutrino oscillation hypothesis, in the range of reconstructed neutrino energy from 475 MeV to 3 GeV. The probability that MiniBooNE and LSND both are due to two-neutrino oscillations is only 2%.”

And I don't know of any more recent experiment that actually proves neutrinos oscillate. Do you?

Neutrinos have definitively been observed changing from one type into another,

BeAChooser
2nd March 2008, 08:18 PM
This means that the temperatures that we are talk about are those of normal fusion, i.e. millions of Kelvin.

It might interest you to know that z-pinches have actually achieved temperatures in the billions of Kelvin.

If there are z-pinches occurring anywhere on the surface of the Sun then we have to wonder why astronomers have never noticed these massively hot (million K!) spots. Why have the many satellites observing the Sun not recorded them?

http://hesperia.gsfc.nasa.gov/hessi/flares.htm "Overview of Solar Flares ... snip ... A composite spectrum of a large flare is shown in the figure below, where the contributions to the total emission are indicated in the different energy ranges. The longer wavelength or softer X rays from less than 1 keV to several tens of keV are produced by hot plasma with a temperature of at least 107 K (and possibly as high as several times 108 K in some cases)."

BeAChooser
2nd March 2008, 08:22 PM

Neutrinos have definitively been observed changing from one type into another

Well name the experiment that definitively showed that.

Acleron
2nd March 2008, 09:12 PM
Well name the experiment that definitively showed that.

Here's three that contributed to current understanding.

Super-Kamiokande (http://www-sk.icrr.u-tokyo.ac.jp/sk/index1.html)

Sudbury (http://nobelprize.org/nobel_prizes/physics/articles/bahcall/)

Kamland (http://kamland.lbl.gov/)

BeAChooser
2nd March 2008, 09:42 PM
Here's three that contributed to current understanding.

Super-Kamiokande (http://www-sk.icrr.u-tokyo.ac.jp/sk/index1.html)

I see nothing at that site stating they proved neutrinos oscillate.

Sudbury (http://nobelprize.org/nobel_prizes/physics/articles/bahcall/)

Sudbury just ASSUMED they oscillate, like I said. They didn't prove it.

Kamland (http://kamland.lbl.gov/)

Kamland's results are very controversial and the more recent experiment I linked above did NOT confirm their result.

Reality Check
2nd March 2008, 10:47 PM
BeAchooser
hesperia.gsfc.nasa.gov/hessi/flares.htm "Overview of Solar Flares ... snip ... A composite spectrum of a large flare is shown in the figure below, where the contributions to the total emission are indicated in the different energy ranges. The longer wavelength or softer X rays from less than 1 keV to several tens of keV are produced by hot plasma with a temperature of at least 107 K (and possibly as high as several times 108 K in some cases)."
That article is about flares not z-pinches. Flares of course contain plasmas that can have very high temperatures but they have nothing to do with z-pinches. The question I asked is about z-pinches. Why have they have not been observed if they are as energenic as the laboratory experiments you quote suggest?
In addition do you have a calculation of how many z-pinches it would take to produce the observed neutrino flux? My impression is that there would have to be on the order of millions per second but please prove me wrong if you can.

Forget about the question of neutrino oscillations. Just tell us how your model produces neutrinos and whether the predicted flux matches the observed result. If oscillations exist then we just multiply the number of observed neutrinos by 3. If they do not then we just accept the number seen. In either case I would be interested if you can provide a prediction that is even an order of magnitude of the observed result.

Reality Check
2nd March 2008, 11:27 PM
Wikipedia have a good article on neutrino oscillation for those who are interested.
BeAChooser
Note that the previously posted URL for Super-Kamiokande contains their neutrino oscillation data only in PostScript format but their original July 3 1998 paper to Physical Review Letters is at www-sk. icrr. u-tokyo.ac.jp/doc/sk/pub/nuosc98.submitted.pdf.
Also the MiniBooNE analysis is still ongoing but there is a paper published that states: The MiniBooNE Collaboration reports first results of a search for $\nu_e$ appearance in a $\nu_\mu$ beam. With two largely independent analyses, we observe no significant excess of events above background for reconstructed neutrino energies above 475 MeV. The data are consistent with no oscillations within a two neutrino appearance-only oscillation model.In other words there was no evidence for muon neutrino to electron neutrino oscillations in the LSND region, refuting a simple 2-neutrino oscillation interpretation of the LSND results. This does not refute a more complex neutrino oscillation interpretation of the LSND results.
The Sudbury Neutrino Observatory did not assume neutrino oscillations. Their results demonstrated neutrino oscillations. Read their first results paper at www .sno .phy .queensu.ca/sno/first_results/sno_first_results.pdf.

Complexity
3rd March 2008, 12:18 AM
Well shut up then. Did you really need to post that comment?

I see no derogatory comments aimed at you. Whats your problem, really?

No problem here.

I despise woo.

Acleron
3rd March 2008, 02:46 AM
Super-Kamiokande (http://www-sk.icrr.u-tokyo.ac.jp/sk/index1.html)

I see nothing at that site stating they proved neutrinos oscillate.

Sudbury (http://nobelprize.org/nobel_prizes/physics/articles/bahcall/)

Sudbury just ASSUMED they oscillate, like I said. They didn't prove it.

Kamland (http://kamland.lbl.gov/)

Kamland's results are very controversial and the more recent experiment I linked above did NOT confirm their result.

All the results are explainable by neutrino conversion. The miniBoone results do not deny conversion.

Dancing David
3rd March 2008, 03:22 AM
It might interest you to know that z-pinches have actually achieved temperatures in the billions of Kelvin.

http://hesperia.gsfc.nasa.gov/hessi/flares.htm "Overview of Solar Flares ... snip ... A composite spectrum of a large flare is shown in the figure below, where the contributions to the total emission are indicated in the different energy ranges. The longer wavelength or softer X rays from less than 1 keV to several tens of keV are produced by hot plasma with a temperature of at least 107 K (and possibly as high as several times 108 K in some cases)."

Okay, so where does the energy that powers the sun come from BAC, it is what?

You have elucidated so many different things and now I am asking you:

Where does the energy that powers the sun come from, what rough proportions if it is a mix?

The electric sun has been presented by you, were you just rattling chanins?

BeAChooser
3rd March 2008, 11:53 AM
That article is about flares not z-pinches. Flares of course contain plasmas that can have very high temperatures but they have nothing to do with z-pinches.

You sure?

http://adsabs.harvard.edu/full/1976SoPh...49...95V "Solar flares and plasma instabilities - Observations, mechanisms and experiments,
Authors: van Hoven, G., Journal: Solar Physics, vol. 49, July 1976 ... snip ... Several models have been suggested for the configuration and initial instability involved in a large or sunspot flare. ... snip ... On the right in this figure is shown the model of Alfven and Carlqvist (1967) in which a pre-existing current filament is somehow pinched at one point. They propose a new charge-separation instability driven by the resulting large super-thermal electron drift, which causes a substantial resistivity increase and interruption of the current. The inductive energy of the entire circuit is then dumped at this point. ... snip ... Let us now turn our attention to several laboratory experiments which have attempted to reproduce the theoretical predictions of these last two sections and, therefore, to model a solar flare. ... snip ... This is the double-inverse-pinch experiment, in which large currents are pulsed in parallel through two insulated rods. ... snip ... A similar experiment is that of Dailey, Davis and Lovberg, (1972); Davis and Dailey, 1973), shown in Figure 12. The flat annular pinch is produced by an inductive discharge in the background neutral hydrogen gas ... snip ... Figure 13 is an example of a more conventional plasma experiment, the annular, or hard-core, Z-pinch of Anderson and Kunkel (1969)."

Notice that every one of the experiments mentioned includes a pinch, even when they are claiming that magnetic reconnection is occuring.

Here are some later references that seem to mention pinches as possible explanations for flares:

http://www.osti.gov/energycitations/product.biblio.jsp?osti_id=6878842 "Phenomenological model of solar flares, 1978, Astrophys. J. ; Vol/Issue: 221:3, ... snip ... imply that the flare process is a near quasi-static and quasi-thermal steady-state dissipative flux annihilation of the parallel current density associated with a helical twisted flux tube. Classical thermal conductivity along the lines of force and the tangled-flux surface model of controlled-fusion B/sub z/ pinch experiments lead to a buffered steady-state electron temperature < or =2 x 107 K, the almost universally observed thermal X-ray temperature."

http://www.springerlink.com/content/kt40937w26383v30/ "The linear Z pinch and the stellar flare phenomenon, V. S. Airapetyan and A. G. Nikogosyan, 1988"

http://www.springerlink.com/content/n176h043j83m8q17/ " Pinch mechanism of energy release of stellar flares, V. S. Airapetyan, V. V. Vikhrev, V. V. Ivanov and G. A. Rozanova, 1990"

And here's a really current source ... from Sandia Labs, no less.

http://www.physlink.com/News/060312SandiaZ.cfm "Sandia’s Z machine has produced plasmas that exceed temperatures of 2 billion degrees Kelvin — hotter than the interiors of stars. The unexpectedly hot output, if its cause were understood and harnessed, could eventually mean that smaller, less costly nuclear fusion plants would produce the same amount of energy as larger plants. The phenomena also may explain how astrophysical entities like solar flares maintain their extreme temperatures."

BeAChooser
3rd March 2008, 12:02 PM
The Sudbury Neutrino Observatory did not assume neutrino oscillations. Their results demonstrated neutrino oscillations.

Now how exactly did they do that measuring only the neutrino flux here on earth? Care to explain that? :confused:

Reality Check
3rd March 2008, 04:05 PM
Now how exactly did they do that measuring only the neutrino flux here on earth? Care to explain that?
It is simple - just read the links. Basically detectors typically burried in mines to eliminate background radiation.
Are you saying that every solar flare is a z-pinch? The articles you quote state that solar flares MAY BE caused by or contain z-pinches.

Are you going to answer my original question? "Just tell us how your model produces neutrinos and whether the predicted flux matches the observed result"

BeAChooser
3rd March 2008, 06:42 PM
The miniBoone results do not deny conversion.

http://cosmicvariance.com/2007/04/11/miniboone-neutrino-result-guest-blog-from-heather-ray/ "The MiniBooNE neutrino data set agrees with the no neutrino oscillation hypothesis, in the range of reconstructed neutrino energy from 475 MeV to 3 GeV.”

BeAChooser
3rd March 2008, 06:49 PM
Quote:
Now how exactly did they do that measuring only the neutrino flux here on earth? Care to explain that?

It is simple - just read the links. Basically detectors typically burried in mines to eliminate background radiation.

You misunderstand. I'm not asking whether they successfully detected the existence of neutrinos or how they did that. I'm asking how they could tell from a neutrino measurement made only on earth that some neutrinos oscillated between the sun and here ... given that there was no detector anywhere else but here on earth.

The articles you quote state that solar flares MAY BE caused by or contain z-pinches.

Well isn't that what you were doubting when you told us there was no connection between z-pinches and solar flares? :)

kallsop
3rd March 2008, 06:53 PM
Wikipedia has a good article on sunspots where is is clearly stated that they are only dark in contrast to the surrounding material. A temperature of 4000-4500 K means that they are brighter than an electric arc.

Which is how it is possible to project a partially black image onto a white screen in a partially illuminated room. Dark spot projectors are still in development :)

Reality Check
3rd March 2008, 07:05 PM
I'm asking how they could tell from a neutrino measurement made only on earth that some neutrinos oscillated between the sun and here ... given that there was no detector anywhere else but here on earth.

So you agreee with me that the papers merely suggest a connection between z-pinches and solar flares? That they do not prove a connection between pinches and solar flares?

Reality Check
3rd March 2008, 07:15 PM
BeAChooser
Another point: If z-pinches are the source of all of the solar neutrinos and z-pinches are caused only by solar flares then we would expect the neutrino flux to vary a lot, i.e. from zero when there are no flares to a high value when there are flares. Since solar flares occur several times a day and the neutrino detection experiments run for years contuniously collecting data then the change in flux would be detected. The neutrino flux would also change during the sun-spot cycle if z-pinches are associated with sun spots and would again be detected by the experiments. This variation would be Nobel Prize winning material but has not been reported.

sol invictus
3rd March 2008, 07:17 PM
FYI, Miniboone ruled out the results of the LSND experiment. That's as expected, because the LSND results were incompatible with all the other experiment done on neutrino oscillations (which agree with each other). Miniboone did NOT rule out neutrino oscillations in the range where they should be according to everybody but LSND - it has nothing to say about them.

You can see that on this plot - the expected range for delta m^2 is well below the exclusion region (which is above and to the right of the sold line).

http://dnp.nscl.msu.edu/limitdata_stacked.png

BeAChooser
3rd March 2008, 07:47 PM

That report is a little tough to read but they do appear to have reasonably inferred from the measurements that there are other flavored neutrinos in an amount that matches predictions. This is an easier to read source: http://209.85.173.104/search?q=cache:8SY2Z_AU-pkJ:www.nature.com/physics/highlights/6840-3.html+CC+ES+SNO+neutrinos&hl=en&ct=clnk&cd=26&gl=us . Ok, I'm convinced that the sun might be mostly nuclear powered.

That still leaves the question of what role electric current plays in the behavior of the sun and throughout the solar system. The role that pinches, birkeland currents, and double layers play. And it's still possible that some percentage of those neutrinos derive from those electric phenomena (since those neutrinos would presumable also oscillate from the moment of creation). I wonder ... has there been any thought to building a neutrino *camera* with enough resolution to tell where the neutrinos are actually coming from in the sun? Is it a point source near the core, or sources possible scattered throughout the body or near the surface?

BeAChooser
3rd March 2008, 08:02 PM
The neutrino flux would also change during the sun-spot cycle if z-pinches are associated with sun spots and would again be detected by the experiments. This variation would be Nobel Prize winning material but has not been reported.

Actually it has. And may still be an open issue.

http://www.maths.qmul.ac.uk/~lms/research/neutrino.html

"Neutrinos and Sunspots: Any Correlation?

The Homestake experiment has been running for over two solar activity cycles (1 activity cycle = 11 years approximately) and it has been noticed that the neutrino fluxes are not constant. Many researchers have tried to link solar surface activity with neutrino fluxes and, depending upon whether you believe their statistical arguments, have succeeded. It has been claimed that the neutrino flux is correlated to solar radius and solar wind mass flux; and anti-correlated to line-of-sight magnetic flux, p-mode frequencies, and (you guessed it) sunspots. (If two quantities are correlated, then they increase and decrease together. If two quantities are anti-correlated, then when one increases, the other decreases, and vice versa.)

Many of these parameters are (anti-) correlated with each other and are internally consistent. The solar activity cycle is usually defined by sunspot numbers but sunspots are related to magnetic activity in the Sun. Many of these other parameters are also directly affected by magnetism. If these correlations really exist, then it would seem that neutrinos are reacting with the magnetic fields in the heliosphere and magnetosphere. Thus, from this evidence, the solution to the solar neutrino problem is a physical one.

Another possibility, rarely discussed, is that the solar neutrino flux is actually constant and it is the cosmic ray background that is varying. Cosmic rays are more likely to get through to the Earth during periods of low solar activity. Therefore, neutrinos generated in the Earth's atmosphere by cosmic rays will increase in number during these times. If this cosmic background flux is not correctly subtracted from the total detections, then it will appear that the solar flux is indeed varying with the solar cycle.

And note that EU theorists say their theory would predict an anti-correlation between sunspot activity and neutrino flux.

Reality Check
3rd March 2008, 10:13 PM
That report is a little tough to read but they do appear to have reasonably inferred from the measurements that there are other flavored neutrinos in an amount that matches predictions. ... Ok, I'm convinced that the sun might be mostly nuclear powered.

That still leaves the question of what role electric current plays in the behavior of the sun and throughout the solar system. The role that pinches, birkeland currents, and double layers play. And it's still possible that some percentage of those neutrinos derive from those electric phenomena (since those neutrinos would presumable also oscillate from the moment of creation). I wonder ... has there been any thought to building a neutrino *camera* with enough resolution to tell where the neutrinos are actually coming from in the sun? Is it a point source near the core, or sources possible scattered throughout the body or near the surface?
The sun is entirely fusion powered since the measured neutrino flux is that predicted by the model of a fusion powered sun. We know how much energy the sun emits. We calculate the amount of fusion that produces this amount of energy. This fusion produces a neutrino flux and we measure that flux.

The role of electric current in the sun is minor. The role that pinches, birkeland currents, and double layers play are minor.

It is impossible for neutrinos to be derived from "electric phenomena". They are due to nuclear interactions not electrical ones.

There is little possibility of a neutrino "camera" since they do not interact enough with matter to be brought to a focus.

Reality Check
3rd March 2008, 10:19 PM
And note that EU theorists say their theory would predict an anti-correlation between sunspot activity and neutrino flux.
In other words the more sunspots, the fewer neutrinos. If sunspots had any relationship with z-pinches and so with fusion reactions then more sunspots would mean more neutrinos.

Dancing David
4th March 2008, 04:30 AM
Ok, I'm convinced that the sun might be mostly nuclear powered.

Okay, I already conceded that there is a role for EM in physics. What role do you want Birkeland currents to have?

Dancing David
4th March 2008, 04:31 AM
Upon reflection and trying to remember, I think that BAC may have posted a picture of a solar flare when asked where a Birkeland current entered the sun.

So I was mistaken, it was a flare and not a sun spot.

robinson
4th March 2008, 07:08 AM
Ok, I'm convinced that the sun might be mostly nuclear powered.

Whoohoo! Am I the only one that considers that a huge thing? Congratulations BeAChooser. You have exhibited the open mind. A thing of beauty.

That still leaves the question of what role electric current plays in the behavior of the sun and throughout the solar system.

I would say "the role of electromagnetism in the behavior of the sun". And solar system. And Galaxy. And Universe.

But that is another topic.

sol invictus
4th March 2008, 07:15 AM
Whoohoo! Am I the only one that considers that a huge thing? Congratulations BeAChooser. You have exhibited the open mind. A thing of beauty.

I have him on ignore. So now he thinks it's "mostly" fusion powered? As in, maybe the electric sun garbage is only 90% wrong?

Darth Rotor
4th March 2008, 07:32 AM
Well shut up then. Did you really need to post that comment?

I see no derogatory comments aimed at you. Whats your problem, really?
He doesn't suffer fools gladly, nor should he.

(Complexity, sorry to speak for you, but I have had the same approach in the net for many years, NSFG.)

sol: thanks for the graph, most informative.

DR

Belz...
4th March 2008, 09:53 AM
Ok, I'm convinced that the sun might be mostly nuclear powered.

Well, there's something I don't see every day. Congratulations.

BeAChooser
4th March 2008, 10:00 AM
The role of electric current in the sun is minor.

Where do magnetic fields come from?

The role that pinches, birkeland currents, and double layers play are minor.

Funny. Even the folks who claim magnetic reconnection is the key keep talking about pinches. And just because YOU can't recognize a Birkeland current when you see one or insist on renaming it a "flux tube" doesn't mean it's not important to the way the sun behaves in the solar system. And likewise, magnetic reconnection may just be a renaming of the exploding double layer phenomena ... without truly understanding what is going on. :D

It is impossible for neutrinos to be derived from "electric phenomena". They are due to nuclear interactions not electrical ones.

If electrically induced pinches produce nuclear interactions then neutrinos can result from electrical phenomena.

There is little possibility of a neutrino "camera" since they do not interact enough with matter to be brought to a focus.

What a shame. ;)

BeAChooser
4th March 2008, 10:09 AM
In other words the more sunspots, the fewer neutrinos. If sunspots had any relationship with z-pinches and so with fusion reactions then more sunspots would mean more neutrinos.

I've never claimed that z-pinches are related to sunspots. And I tried to correct that bit of misinformation David introduced to this thread out earlier. Guess you missed it.

The EU theorists state that

http://www.electric-cosmos.org/sun.htm

Fusion in the Double Layer

The z-pinch effect of high intensity, parallel current filaments in an arc plasma is very strong. Whatever nuclear fusion is taking place on the Sun is occurring here in the double layer (DL) at the top of the photosphere (not deep within the core). The result of this fusion process are the "metals" that give rise to absorption lines in the Sun's spectrum. Traces of sixty eight of the ninety two natural elements are found in the Sun's atmosphere. Most of the radio frequency noise emitted by the Sun emanates from this region. Radio noise is a well known property of DLs. The electrical power available to be delivered to the plasma at any point is the product of the E-field (Volts per meter) times current density (Amps per square meter). This multiplication operation yields Watts per cubic meter. The current density is relatively constant over the height of the photospheric / chromospheric layers. However, the E-field is by far the strongest at the center of the DL. Nuclear fusion takes a great deal of power - and that power is available in the DL.

It is also observed that the neutrino flux from the Sun varies inversely with sunspot number. This is expected in the ES hypothesis because the source of those neutrinos is z-pinch produced fusion which is occurring in the double layer - and sunspots are locations where there is no DL in which this process can occur.

It would help if you people even tried to understand the theory you are arguing against. ;)

BeAChooser
4th March 2008, 10:12 AM
I have him on ignore.

You keep saying that but keep responding to my posts. :p

Reality Check
4th March 2008, 11:06 AM
I've never claimed that z-pinches are related to sunspots. And I tried to correct that bit of misinformation David introduced to this thread out earlier. Guess you missed it.

The EU theorists state that ...

It would help if you people even tried to understand the theory you are arguing against.
A discussion of the Electric Universe hypothesis is off topic which is "Z-pinch Sunspots". It looks like everyone agrees - there is no relationship between z-pinches and sunspots.

robinson
4th March 2008, 11:25 AM
On the z-pinch and sunspots as examples of z-pinch phenomena.

In other threads much of the electric sun model has been discussed at some lenth and confusion of subject matter. A certain poster has made two claims in seperate threads, one that sunspots are where Birkeland currents enter the sun. And in another that sunspots are an example of possible z-pinch effect and that this provides the energy for the sun. ...

Of course I am sure I missing something here.

David, once again you misrepresent what I actually said. I'm not certain whether I ever linked something that made the first claim. I suppose it's possible. But I certainly didn't make the second claim. I drew your attention to an image that happens to have a sunspot in it but it also has something else ... an bright many filamented event in the vicinity but not directly over the sunspot. And that might be a z-pinch. I made every effort to get you to look at that something else but apparently your blinders made it impossible for you to see anything but the sunspot. :rolleyes:

Well, I'm glad we got that cleared up.

Dancing David
4th March 2008, 12:16 PM
So how does the energy get from the filimentary z-pinch to the rest of the sun BAC, are there enough of these z-pinches to illuminate the sun?

Reality Check
4th March 2008, 01:09 PM
So how does the energy get from the filimentary z-pinch to the rest of the sun BAC, are there enough of these z-pinches to illuminate the sun?
I may be misstating BACs position but if he supports the "Fusion in the Double Layer" quote that he posted then he believes that the sun is illuminated by fusion happening in a layer at the top of the photosphere.
Any hypothetical filimentary z-pinches will occur several times a day (the frequency of solar flares) and will not be a major factor in the sun's illumination. Or maybe these hypothetical filimentary z-pinches are just around sunspots and so still low in number.

Dancing David
4th March 2008, 01:27 PM
Well hopefully the answer will be less than opaque and not "You are a dolt david". I got the impression that there was a wide area of double layer that was spherical as well.

Reality Check
4th March 2008, 07:23 PM
Electric Universe theorists have suggested that there is a spherical double layer at the top of the photosphere and that this is where the fusion powering the sun happens. See the link in BeAChooser's post. But the hypothesis stated there has many problems, e.g. no correlation between solar activity and neutrino flux as in the paper published in 2000
"Correlative Aspects of the Solar Electron Neutrino Flux and Solar Activity" (http://www.journals.uchicago.edu/doi/abs/10.1086/317787).

Scientists persist with the standard model of fusion for stars because it works. They know that a sustained fusion reaction will happen if you subject hydrogen to high temperatures and high pressures. This is exactly the situation in the core of stars. The standard model predicts the observed abundance of elements in the stars, what happens during a star's lifetime, the cause of supernovae, etc.

Dancing David
5th March 2008, 04:47 AM
Well the spherical double layer would have some observable things as well, the biggest question I would have would be, what holds it together, at that temperature and pressure? And how does that work for a red giant?

RC, you will find that BAC does not answer direct questions, he will point some way and spin but not usually answer.

BeAChooser
5th March 2008, 12:04 PM
They know that a sustained fusion reaction will happen if you subject hydrogen to high temperatures and high pressures.

Actually they don't "know" this since they can't actually observe the core to see all the parameters affecting the problem. Perhaps that's why after more than a half century, they still haven't been able to produce a "sustained" fusion reaction in the lab. Who knows ... perhaps they'll have to introduce another gnome to make it happen? :D

Reality Check
5th March 2008, 12:15 PM
Where do magnetic fields come from?
Funny. Even the folks who claim magnetic reconnection is the key keep talking about pinches. And just because YOU can't recognize a Birkeland current when you see one or insist on renaming it a "flux tube" doesn't mean it's not important to the way the sun behaves in the solar system. And likewise, magnetic reconnection may just be a renaming of the exploding double layer phenomena ... without truly understanding what is going on. :D

If electrically induced pinches produce nuclear interactions then neutrinos can result from electrical phenomena.

Magnetic fields come from electric currents. Solar magnetic fields have a important role in stars but little role beyond the surface of a star. They do have a role in flares and solar winds but these are minor phenomena, i.e. do not affect a stellar system as a whole. So the energy source of the sun is a major effect. The solar wind today is a minor effect - when was the last time that a planet was blown out of its orbit by the solar wind? :rolleyes:
I agree that electrical phenomena may indirectly create neutrinos. However the big word in your reply is "If". No pinch (zeta, theta or other) in the laboratory has produced fusion. You should not try to project possible future results under tightly controlled conditions onto the chaotic conditions of the sun. The best that you can say is that pinches produce plasmas with high temperatures and so the observed high temperatrures ini flares may be due to pinches.

Reality Check
5th March 2008, 12:19 PM
Actually they don't "know" this since they can't actually observe the core to see all the parameters affecting the problem. Perhaps that's why after more than a half century, they still haven't been able to produce a "sustained" fusion reaction in the lab. Who knows ... perhaps they'll have to introduce another gnome to make it happen? :D
We do not have to observe the core of the sun to know it exists. The parameters are simple - temperature and pressure. We know the parameters because we have done it - ever hear of the hydrogen bomb :) ? The core of the sun is basically a lot of hydrogen bombs.

robinson
5th March 2008, 12:21 PM
Err, I don't think that is correct.

Reality Check
5th March 2008, 12:27 PM
RC, you will find that BAC does not answer direct questions, he will point some way and spin but not usually answer.
Hi DD. I have seen BAC on other threads and he does have a tendency to spin questions. He has been fairly reasonable on this thread but at least he has admitted that the sun is "mostly fusion powered".
I suspect (please tell me that I am wrong BAC!) that the electrically-powered sun will reappear from him in the future.
In any case this is a useful exercise for me since it enables me to reconnect with my physics background after 20 years in IT.

Reality Check
5th March 2008, 12:30 PM
Err, I don't think that is correct.
"The core of the sun is basically a lot of hydrogen bombs" is simplistic but not totally wrong. Another analogy would be 1 enormous hydrogen bomb that has been exploding for the last few billion years.

sol invictus
5th March 2008, 04:02 PM
"The core of the sun is basically a lot of hydrogen bombs" is simplistic but not totally wrong. Another analogy would be 1 enormous hydrogen bomb that has been exploding for the last few billion years.

Yes, that's basically correct. It's only in the core (which ends maybe 1/4 of the way out from the center) that the fusion is taking place, and it's not exactly the same set of reactions used in modern hydrogen bombs, but those are relatively minor points.

In both cases the primary power source is the fusion of hydrogen into helium.

BeAChooser
5th March 2008, 05:00 PM
Magnetic fields come from electric currents.

You don't say? :jaw-dropp

You'd be surprised at the number of mainstream papers and articles that forget to mention that little fact ... that act like the magnetic fields just appeared out of nowhere.

Solar magnetic fields have a important role in stars but little role beyond the surface of a star.

Well how far do solar magnetic fields extend above the surface of the sun? To the corona? A little beyond that?

They do have a role in flares and solar winds but these are minor phenomena, i.e. do not affect a stellar system as a whole.

Surely you aren't saying that flares and solar winds are minor phenomena and do not affect the stellar system as a whole. Surely.

The solar wind today is a minor effect - when was the last time that a planet was blown out of its orbit by the solar wind?

Oh, I guess you are! :D

No pinch (zeta, theta or other) in the laboratory has produced fusion.

http://tech.groups.yahoo.com/group/undernetphysics/message/230 "The big news out of the April APS Meeting in Philadelphia this week (as reported by ScienceNow) is the report out of Sandia National Lab of the first ever hydrogen fusion using the Z pinch machine."

http://sciencenow.sciencemag.org/cgi/content/citation/2003/408/2 "Electrical Pinch Fuses Hydrogen"

:blush:

BeAChooser
5th March 2008, 05:12 PM
The parameters are simple - temperature and pressure.

You forgot at least one. Time.

We know the parameters because we have done it - ever hear of the hydrogen bomb :) ?

So you think a hydrogen bomb is a sustained fusion reaction? Do you know how long fusion actually lasts in a hydrogen bomb?

The core of the sun is basically a lot of hydrogen bombs.

But that doesn't really describe the approach that mainstream physicists have been trying in controlled fusion experiments the last 40 years, does it?

http://query.nytimes.com/gst/fullpage.html?res=9805E0D71338F93BA35757C0A9659C8B 63 " New Fusion Method Offers Hope of New Energy Source, By KENNETH CHANG
Published: April 8, 2003, With a blast of X-rays compressing a capsule of hydrogen to conditions approaching those at the center of the Sun, scientists from Sandia National Laboratories reported today that they had achieved thermonuclear fusion, in essence detonating a tiny hydrogen bomb. "It's the first observation of fusion for a pulsed power source,'' said Dr. Ramon J. Leeper, manager of the target physics department at Sandia, in Albuquerque, who presented the findings at a meeting of the American Physical Society here. Most fusion efforts have tried to use magnetic fields to compress hydrogen to temperatures hot enough for fusion to occur continuously, as it does in the Sun. But sustaining a dense hot cloud of hydrogen gas has proved trickier than scientists thought when they started fusion experiments 50 years ago."

On the other hand, a hydrogen bomb does describe the z-pinch approach. And you've heard of those, haven't you? :D

BeAChooser
5th March 2008, 05:21 PM
Originally Posted by Reality Check
"The core of the sun is basically a lot of hydrogen bombs" is simplistic but not totally wrong. Another analogy would be 1 enormous hydrogen bomb that has been exploding for the last few billion years.

Yes, that's basically correct. ... snip ... it's not exactly the same set of reactions used in modern hydrogen bombs, but those are relatively minor points.

ROTFLOL! If they are so minor, sol, why haven't they been able to sustain fusion in the lab ... after 50 years of trying ... and billions and billions of dollars spent in research? :p

Ziggurat
5th March 2008, 05:35 PM
So you think a hydrogen bomb is a sustained fusion reaction?

I don't believe he made that claim.

Do you know how long fusion actually lasts in a hydrogen bomb?

Do you know how long you can sustain high pressure in a hydrogen bomb?

But that doesn't really describe the approach that mainstream physicists have been trying in controlled fusion experiments the last 40 years, does it?

Well, duh. That's because we have no possible mechanism available on earth for maintaining such high pressures. They tend to, you know... explode.

Reality Check
5th March 2008, 06:02 PM
The links are a bit old (2003) but looking up Google does show that Sandia have has success.
So it looks like z-pinches can create fusion under laboratory conditions. Of course the sun is not a laboratory and so it would be nice to see proof of z-pinches and fusion from them on the sun.

BeAChooser
5th March 2008, 06:22 PM
Originally Posted by BeAChooser
So you think a hydrogen bomb is a sustained fusion reaction?

I don't believe he made that claim.

So when I wrote "they still haven't been able to produce a 'sustained' fusion reaction in the lab." and he responded "We do not have to observe the core of the sun to know it exists. The parameters are simple - temperature and pressure. We know the parameters because we have done it - ever hear of the hydrogen bomb ?", you don't think he was claiming a hydrogen bomb is a sustained fusion reaction? Ok, suit yourself, Ziggurat. :rolleyes:

Well, duh. That's because we have no possible mechanism available on earth for maintaining such high pressures. They tend to, you know... explode.

Looks to me like you are saying its *obvious to you* that nuclear physicists have wasted 40 years and billions and billions of dollars pursuing an approach that was doomed from the start ... where there is "NO POSSIBLE MECHANISM" available on earth to maintain the required pressures? Is that right, Ziggurat? Are you calling all those researchers incompetent or so eager to get the billions that they ignored the obvious? I'm frankly surprised to hear that sort of statement coming from you. :D

ben m
5th March 2008, 06:35 PM
Looks to me like you are saying its *obvious to you* that nuclear physicists have wasted 40 years and billions and billions of dollars pursuing an approach that was doomed from the start ... where there is "NO POSSIBLE MECHANISM" available on earth to maintain the required pressures? Is that right, Ziggurat? Are you calling all those researchers incompetent or so eager to get the billions that they ignored the obvious? I'm frankly surprised to hear that sort of statement coming from you. :D

Holy cow, BAC, that's the kind of nonsense that makes me keep you on "ignore". I clicked "view post" once and won't do it again.

Did he say "no possible mechanism"? No, you're just making up things to argue with. We haven't done sustained fusion on Earth because we need a pressure/temperature containment mechanism here---as opposed to on the sun, where confinement is provided naturally---and so far the invented mechanisms (tokamaks, stellerators, pinches, NIF) present difficult engineering problems. Physicists are attempting to solve those engineering problems. Did you not know that, or did you pretend not to for the sake of something to sneer about? I don't know which is worse. Back to ignore.

Reality Check
5th March 2008, 07:15 PM
So when I wrote "they still haven't been able to produce a 'sustained' fusion reaction in the lab." and he responded "We do not have to observe the core of the sun to know it exists. The parameters are simple - temperature and pressure. We know the parameters because we have done it - ever hear of the hydrogen bomb ?", you don't think he was claiming a hydrogen bomb is a sustained fusion reaction? Ok, suit yourself, Ziggurat. :rolleyes:
You should have noted the smiley at the end of the comment. It was an analogy not an assertion. I will make my post more explicit:

We know that the sun has a core since it cannot be hollow given that it is composed of plasma.
We know that the core is under high pressure since the sun's gravity is pulling in the plasma. The pressure can be calculated.
We know that the core is at a high temperature because if it was not then it would not be comprised of plasma. The temperature can be calculated.Therefore we find that the temperature and pressure at the core is sufficient for various fusion reactions to occur and it is this that powers the sun. Our understanding of solar fusion is as complete as the science that lead to the hydrogen bomb.

The Man
6th March 2008, 06:58 AM
The links are a bit old (2003) but looking up Google does show that Sandia have has success.
So it looks like z-pinches can create fusion under laboratory conditions. Of course the sun is not a laboratory and so it would be nice to see proof of z-pinches and fusion from them on the sun.

Actually in Sandia National Lab’s Z-machine the Z-pinch does not directly generate fusion but acts as an X-ray source for indirect inertial confinement fusion, the same process used in a hydrogen bomb. The only difference is that in a hydrogen bomb a fast fission device is used as the radiant energy source and not a Z-pinch.

But that doesn't really describe the approach that mainstream physicists have been trying in controlled fusion experiments the last 40 years, does it?

Yes it does, the basic methods for obtaining fusion in laboratory research are magnetic confinement (Tokomak and direct Z-pinched fusion) and inertial confinement (Z-machine, laser and ion beam fusion). Fusion from gravity is a form of inertial confinement fusion.

On the other hand, a hydrogen bomb does describe the z-pinch approach. And you've heard of those, haven't you? :D

No, it does not, it describes the Z-machine approach where the Z-pinch is just a radiant energy source for indirect inertial confinement fusion. Direct Z-pinched fusion is a form of magnetic confinement and differs from the inertial confinement approach used in the Z-machine, the hydrogen bomb and considered to power the sun.

Ziggurat
6th March 2008, 07:20 AM
Looks to me like you are saying its *obvious to you* that nuclear physicists have wasted 40 years and billions and billions of dollars pursuing an approach that was doomed from the start

I'm saying nothing of the sort.

... where there is "NO POSSIBLE MECHANISM" available on earth to maintain the required pressures?

There is indeed no possible method available to us on earth to maintain the pressures that occur in the heart of the sun. Do you dispute that? Can you tell me how we can maintain such pressures? No, you can't. Nor did you even try.

Are you calling all those researchers incompetent or so eager to get the billions that they ignored the obvious?

No. But it's clear that you're clueless about what I am saying. We don't need to produce sustained pressures like the sun in order to produce fusion. We can go to higher temperatures instead (tokamak), or we can do pulsed fusion. The Z-pinch fusion power concept doesn't rely on sustaining fusion, in case you weren't aware. It relies on essentially pulsing mini-hydrogen bomb explosions. That's not sustained fusion, that's just repeated fusion.

Belz...
6th March 2008, 09:36 AM
You'd be surprised at the number of mainstream papers and articles that forget to mention that little fact ... that act like the magnetic fields just appeared out of nowhere.

Maybe it's because it's implicitely understood how they do arise.

ROTFLOL! If they are so minor, sol, why haven't they been able to sustain fusion in the lab ... after 50 years of trying ... and billions and billions of dollars spent in research?

Aren't they using magnetic "pinch" to create nuclear fusion ?

The sun is gravity-powered, when you think about it. It requires very large amounts of gas for the whole thing to work.

Zeuzzz
6th March 2008, 11:00 AM
The sun is gravity-powered, when you think about it. It requires very large amounts of gas for the whole thing to work.

The sun isn't gas, technically, its nearly entirely plasma, which is a different state of matter all together from gas.

BeAChooser
6th March 2008, 01:24 PM
Did he say "no possible mechanism"? No, you're just making up things to argue with.

You mean to say you can't see his post where he stated "we have no possible mechanism available on earth for maintaining such high pressures." Do you have Ziggurat on ignore too, edd? Or are you just trying to embarrass yourself? :D

We haven't done sustained fusion on Earth because we need a pressure/temperature containment mechanism here---as opposed to on the sun, where confinement is provided naturally---and so far the invented mechanisms (tokamaks, stellerators, pinches, NIF) present difficult engineering problems.

But Ziggurat seemed to suggest that such a confinement system isn't possible here on earth. Hence my question about whether physicists were just wasting our money trying to do it. :)

Back to ignore.

Bye bye ben.

BeAChooser
6th March 2008, 01:29 PM
Our understanding of solar fusion is as complete as the science that lead to the hydrogen bomb.

Well then by now don't you think we should have free energy for all? :)

Ziggurat
6th March 2008, 01:46 PM
But Ziggurat seemed to suggest that such a confinement system isn't possible here on earth.

I said you couldn't maintain such pressures on earth. You can't. Nothing you've said precludes that. Nothing I've said precludes that, nor does it preclude producing fusion on earth. I didn't say you couldn't confine the constituents by other (non-pressure) means. And I didn't say you couldn't pulse the fusion (as in the Z-machine).

Look, the highest pressures we can produce sustainably on earth (ie, NOT in an explosion) are around 20 GPa, or 2x1010 Pa, inside diamond anvil cells. Aside from the fact that you can't bring such a cell to very high temperature, that's nowhere near as high pressure as the core of the sun. The sun's core pressure is about 2.5x1011 atmospheres, or about 2.5x1016 Pa. That's 6 orders of magnitude between the highest steady pressures we can produce and the pressure at the center of the sun. God damned straight we can't maintain that kind of pressure. Will you conceed the point? Will you admit you were wrong to contest it? No, I don't expect you will. Because you've never been honest about this debate.

BeAChooser
6th March 2008, 01:58 PM
Originally Posted by BeAChooser
Looks to me like you are saying its *obvious to you* that nuclear physicists have wasted 40 years and billions and billions of dollars pursuing an approach that was doomed from the start

I'm saying nothing of the sort.

Really? Well that seems a little at odds with your very next statement:

There is indeed no possible method available to us on earth to maintain the pressures that occur in the heart of the sun.

According to what I've read, scientists here on earth have been struggling for 50 years to duplicate the temperatures and pressures on the sun so we'd have plentiful controlled fusion electricity and do away with the need to burn oil. But now you are telling us that there is "no possible method" on earth to maintain those pressures so it seems to me you are saying that effort started 50 years ago was sort of a waste of time and money.

That's not sustained fusion, that's just repeated fusion.

Oh. I see. All these researchers are just being *sloppy* with their language:

https://www.llnl.gov/str/Hill.html "Much of the renewed interest in spheromaks is focused on a research effort at Lawrence Livermore called the Sustained Spheromak Physics Experiment (SSPX). ... snip ... According to SSPX leader David Hill, the tokamak concept is considered the leading contender to generate sustained fusion reactions".

http://news.bbc.co.uk/2/hi/science/nature/4328597.stm "Achieving stable and sustained reactions on Earth, however, present an immense challenge. The Iter design is for the reactions to take place inside a 100-million-degree gas (plasma) suspended in an intense doughnut-shaped magnetic field. Iter will consolidate all that has been learnt over many decades of study. It is expected to produce 500MW of fusion power during pulses of at least 400 seconds."

400 second long pulses? And you don't think that's "sustained", Ziggurat?

And note that ITER's objective isn't just 400 second long pulses.

http://www.iter.org/a/index_faq.htm "This also explains ITER's interest in extending pulses to steady state. A reactor operating for only 7 minutes every 30 minutes is not attractive, since little electricity can be produced during much of the "dwell" time, but some plant power is nevertheless consumed then."

Guess you'd better tell them it's NOT POSSIBLE and save us all some development costs. :D

BeAChooser
6th March 2008, 02:01 PM
Aren't they using magnetic "pinch" to create nuclear fusion ?

Isn't it interesting that the "pinch" is an EM phenomena ... not a gravity phenomena. And a phenomena the mainstream astrophysics community mostly ignores. :p

The sun is gravity-powered, when you think about it. It requires very large amounts of gas for the whole thing to work.

Gas? :D

Ziggurat
6th March 2008, 02:12 PM
Really? Well that seems a little at odds with your very next statement:

Not at all. You just can't read. The part you didn't bold is the critical part. We cannot maintain solar core pressures by any means. None of your links contradicts that statement in any way, shape, or form.

Oh. I see. All these researchers are just being *sloppy* with their language:

https://www.llnl.gov/str/Hill.html "Much of the renewed interest in spheromaks is focused on a research effort at Lawrence Livermore called the Sustained Spheromak Physics Experiment (SSPX). ... snip ... According to SSPX leader David Hill, the tokamak concept is considered the leading contender to generate sustained fusion reactions".

What's sloppy about that? I see no indication that he's claiming to produce solar core pressures. So where's the contradiction between what he said and what I said? There is none.

http://news.bbc.co.uk/2/hi/science/nature/4328597.stm "Achieving stable and sustained reactions on Earth, however, present an immense challenge. The Iter design is for the reactions to take place inside a 100-million-degree gas (plasma) suspended in an intense doughnut-shaped magnetic field. Iter will consolidate all that has been learnt over many decades of study. It is expected to produce 500MW of fusion power during pulses of at least 400 seconds."

Once again, no mention of pressure. But there is a mention of a temperature. And low and behold, that temperature is higher than the expected solar core temperature of only about 14 million K. It needs to be higher preciesly because we cannot get the pressure anywhere near as high. Once again, no contradiction, merely your inability to figure out VERY basic ideas.

400 second long pulses? And you don't think that's "sustained", Ziggurat?

Tokamak reactors are indeed looking for sustained fusion. I never said they weren't. But they're looking at pressures much lower than solar core pressures - are you honestly so clueless you couldn't figure that out? It's Z-machines which are not sustained (but pulsed) that can produce ultra-high pressures.

Guess you'd better tell them it's NOT POSSIBLE and save us all some development costs. :D

The Man
6th March 2008, 02:27 PM
Well then by now don't you think we should have free energy for all? :)

How would you define “free energy”, hydrodynamic, solar, geothermal, nuclear fission or even fusion? All of these come with requisite costs; these costs involve production, maintenance and delivery of that energy. Don’t forget that oil is just stored solar energy. “Free energy” is a misnomer; the best we can do is to minimize cost.

The Man
6th March 2008, 05:21 PM
Fuel loading would be one the primary engineering aspects preventing continuously sustained fusion even if temperature and pressure could be continuously maintained (unless you happen to have 1.98 x1030 kg of hydrogen handy). Direct Z-pinched fusion on the surface of the sun would be a pulsed reaction. Unless you maintain that the plasma remains sufficiently pinched while being fuel loaded.

This brings up the question as to what is the fuel source for direct Z-pinched fusion on or in the sun. In proton-proton cycle fusion the deuterium fuel is produced by an energy dependent (taking energy) weak nuclear interaction fusing protons into deuterium nuclei. In a modern hydrogen bomb lithium-deteuride is used as fuel (deteuride being basically deuterium) but also producing 4He and 3H (tritium) when exposing the 6Li to free neutrons (under those temperature and pressure conditions), giving a deuterium tritium fusion reaction. In all of the terrestrial laboratory fusion efforts, deuterium is also the primary fuel used, removing the energy reducing process of producing deuterium from protons. Mind you that the neutrino release only comes from the weak nuclear interaction (energy dependent) producing deuterium nuclei from two protons (by changing one of the protons into a neutron) and not from the energy releasing fusion of deuterium (or deuterium tritium) nuclei into helium nuclei.

http://hyperphysics.phy-astr.gsu.edu/Hbase/astro/procyc.html#c1

The carbon nitrogen oxygen cycle is the fusion considered to dominate in stars twice or more massive then our Sun

http://hyperphysics.phy-astr.gsu.edu/Hbase/astro/carbcyc.html#c1

For deuterium tritium fusion

http://hyperphysics.phy-astr.gsu.edu/Hbase/nucene/fusion.html#c1

For nuclear weapons

http://library.thinkquest.org/17940/texts/nuclear_weapons/nuclear_weapons.html

BeAChooser
6th March 2008, 06:16 PM
The part you didn't bold is the critical part. We cannot maintain solar core pressures by any means. None of your links contradicts that statement in any way, shape, or form.

But I wasn't trying to contradict that statement. In fact, I never tried to contradict it. As long as we agree that the fusion community has indeed been trying to sustain a fusion reaction ... and haven't succeeded ... fine. Keep in mind that this whole conversation started because Reality Check claimed the sun essentially works like a long string of nuclear bombs going off one after the other. That's neither right nor is a string of nuclear bombs going off one after the other "sustained" in the sense that those trying to develop sustained fusion here on earth meant ... at least until very recently. Why you joined in to object when I pointed that out isn't clear.

By the way ... it looks like we wouldn't want to reproduce the fusion occurring in the sun anyway. http://en.wikipedia.org/wiki/Nuclear_fusion "At the temperatures and densities in stellar cores the rates of fusion reactions are notoriously slow. For example, at solar core temperature (T ~ 15*MK) and density (120*g/cm³), the energy release rate is only 276*mW/cm³—about a quarter of the volumetric rate at which a resting human body generates heat." That wouldn't make a very good power source for earthly use. :)

BeAChooser
6th March 2008, 06:18 PM
How would you define “free energy”

I thought I put on a humor tag. :D Perhaps I should have used a sarcasm tag. :rolleyes:

The Man
6th March 2008, 06:34 PM
I thought I put on a humor tag. :D Perhaps I should have used a sarcasm tag. :rolleyes:

Sorry, but your use of smilies is so replete that I never know what you really intend with them, so I have generally disregarded them. I apologize for my oversight.

The Man
6th March 2008, 07:33 PM
By the way ... it looks like we wouldn't want to reproduce the fusion occurring in the sun anyway. http://en.wikipedia.org/wiki/Nuclear_fusion "At the temperatures and densities in stellar cores the rates of fusion reactions are notoriously slow. For example, at solar core temperature (T ~ 15*MK) and density (120*g/cm³), the energy release rate is only 276*mW/cm³—about a quarter of the volumetric rate at which a resting human body generates heat." That wouldn't make a very good power source for earthly use. :)

You neglected to post the rest of that quote supporting Zig’s assertions.

Thus, reproduction of stellar core conditions in a lab for nuclear fusion power production is completely impractical. Because nuclear reaction rates strongly depend on temperature (exp(−E/kT)), then in order to achieve reasonable rates of energy production in terrestrial fusion reactors 10–100 times higher temperatures (compared to stellar interiors) are required T ≈ 0.1–1.0 GK.

The difference being in the volume available (temperature, pressure and volume are related, with the additional caveat of number of molecules).

http://en.wikipedia.org/wiki/Sun#Core

About 3.4 × 1038 protons (hydrogen nuclei) are converted into helium nuclei every second (out of ~8.9 × 1056 total amount of free protons in the Sun), releasing energy at the matter–energy conversion rate of 4.26 million tonnes per second, 383 yottawatts (3.83 × 1026 W) or 9.15 × 1010 megatons of TNT per second. This actually corresponds to a surprisingly low rate of energy production in the Sun's core—about 0.3 µW/cm³ (microwatts per cubic cm), or about 6 µW/kg of matter. For comparison, the human body produces heat at approximately the rate 1.2 W/kg, millions of times greater per unit mass. The use of plasma with similar parameters for energy production on Earth would be completely impractical—even a modest 1 GW fusion power plant would require about 170 billion tonnes of plasma occupying almost one cubic mile. Hence, terrestrial fusion reactors utilize far higher plasma temperatures than those in Sun's interior.

As a volumetric relationship it only says that the energy production per cubic meter of volume is very low. If you don’t want to do the math yourself, 3.83x1026 watts divided by 3 x 10-7 watts per cubic centimeter equals 1.23 x 1033 cubic centimeters or 1.18 x 106 times the volume of the earth. That’s an awful lot of bodies. Bamboozle yourself if you want, but don’t try to bamboozle us.

Reality Check
6th March 2008, 09:43 PM
But I wasn't trying to contradict that statement. In fact, I never tried to contradict it. As long as we agree that the fusion community has indeed been trying to sustain a fusion reaction ... and haven't succeeded ... fine. Keep in mind that this whole conversation started because Reality Check claimed the sun essentially works like a long string of nuclear bombs going off one after the other. That's neither right nor is a string of nuclear bombs going off one after the other "sustained" in the sense that those trying to develop sustained fusion here on earth meant ... at least until very recently. Why you joined in to object when I pointed that out isn't clear.

BAC: Actually I did not claim this as literal fact. I noted that the fusion within the sun was analogous with (i.e. has a likeness to) the fusion in hydrogen bombs. Also that we know the parameters needed for solar fusion as well as we know the parameters needed for hydrogen bombs.

Dancing David
7th March 2008, 04:21 AM
But I wasn't trying to contradict that statement. In fact, I never tried to contradict it. As long as we agree that the fusion community has indeed been trying to sustain a fusion reaction ... and haven't succeeded ... fine. Keep in mind that this whole conversation started because Reality Check claimed the sun essentially works like a long string of nuclear bombs going off one after the other. That's neither right nor is a string of nuclear bombs going off one after the other "sustained" in the sense that those trying to develop sustained fusion here on earth meant ... at least until very recently. Why you joined in to object when I pointed that out isn't clear.

By the way ... it looks like we wouldn't want to reproduce the fusion occurring in the sun anyway. http://en.wikipedia.org/wiki/Nuclear_fusion "At the temperatures and densities in stellar cores the rates of fusion reactions are notoriously slow. For example, at solar core temperature (T ~ 15*MK) and density (120*g/cm³), the energy release rate is only 276*mW/cm³—about a quarter of the volumetric rate at which a resting human body generates heat." That wouldn't make a very good power source for earthly use. :)

Appeal to emotions, is the potentialy fusing core of the sun the size of a human body?

Belz...
7th March 2008, 12:17 PM
The sun isn't gas, technically, its nearly entirely plasma, which is a different state of matter all together from gas.

More-or-less. Doesn't change what I said.

Belz...
7th March 2008, 12:19 PM
Isn't it interesting that the "pinch" is an EM phenomena ... not a gravity phenomena. And a phenomena the mainstream astrophysics community mostly ignores. :p

It's interesting you didn't spot how what I said contradicts what you said.

We're talking about labs, NOT the sun.

Gas? :D

Yeah, where plasma is a subset of gas under some definitions.

Ziggurat
7th March 2008, 12:58 PM
But I wasn't trying to contradict that statement. In fact, I never tried to contradict it. As long as we agree that the fusion community has indeed been trying to sustain a fusion reaction ... and haven't succeeded ... fine.

Two problems with this claim. First off, magnetic confinement (ala Tokamak reactors) is the only method being pursued seriously which is a sustained reaction. Z-machines and laser implosion devices are not sustained. They would be pulsed.

Secondly, it's simply false that they haven't succeeded at producing sustained fusion. They have. The problem is not getting fusion, it's getting efficient fusion which can actually produce more power than it takes to run. That's the engineering challenge. But if you just want to get some fusion, hell, there are table top devices (http://en.wikipedia.org/wiki/Pyroelectric_fusion) which can do that.

Keep in mind that this whole conversation started because Reality Check claimed the sun essentially works like a long string of nuclear bombs going off one after the other.

Analogies are frequently imperfect. The irony here is the frequent appeal to such analogies used by EU proponents in place of actual numerical models.

Why you joined in to object when I pointed that out isn't clear.

I jumped in because you seem to be under the impression that high temperatures and pressures like those found in the sun are not enough to sustain fusion reactions at the rate necessary to produce the power output of the sun. But they are. We cannot recreate such a process in a sustained manner on earth simply because we cannot sustain those pressures. Do you disagree with that?

BeAChooser
8th March 2008, 03:27 PM
We cannot recreate such a process in a sustained manner on earth simply because we cannot sustain those pressures. Do you disagree with that?

No.

Do you agree that fusion may be occurring on the sun anywhere that z-pinch phenomena might be active?

Ziggurat
8th March 2008, 04:03 PM
Do you agree that fusion may be occurring on the sun anywhere that z-pinch phenomena might be active?

I've got no reason to think the current densities are ever large enough to drive significant Z-pinching. Even if it were, I've got even less reason to think that it's going to contribute any significant fraction of the sun's power output. No, I'll take it a step further: I have reason to think that Z-pinch driven fusion CANNOT produce a significant fraction of the sun's power, because there's no strong feedback mechanism.


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NCERT Solutions for Class 12 Biology Chapter 6 Molecular Basic of Inheritance PDF – eSaral

# NCERT Solutions for Class 12 Biology Chapter 6 Molecular Basic of Inheritance PDF

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If you want to learn and understand class 12 Biology Chapter 6 “Molecular Basic of Inheritance” in an easy way then you can use these solutions PDF.

NCERT Solutions helps students to Practice important concepts of subjects easily. Class 12 Biology solutions provide detailed explanations of all the NCERT questions that students can use to clear their doubts instantly.

If you want to score high in your class 12 Biology Exam then it is very important for you to have a good knowledge of all the important topics, so to learn and practice those topics you can use eSaral NCERT Solutions.

In this article, we have listed NCERT Solutions for Class 12 Biology Chapter 6 Molecular Basic of Inheritance PDF that you can download to start your preparations anytime.

So, without wasting more time Let’s start.

Question 1. Group the following as nitrogenous bases and nucleosides: Adenine, Cytidine, Thymine, Guanosine, Uracil, and Cytosine

Solution: Cytidine and Guanosine are the nucleosides.

Adenine, Cytosine, Thymine and Uracil are the nitrogenous bases.

Question 2. If a double-stranded DNA has 20 percent of cytosine, calculate the percentage of adenine in DNA.

Solution. According to Chargaff’s rule, DNA from any cell of any organisms should have a 1:1 ratio of pyrimidine and purine bases $(\mathrm{A}=\mathrm{T}$ and $\mathrm{G}=\mathrm{C}$ ).

The given percent of cytosine is $20 .$ So, the percent of guanine will also be 20 , according to Chargaff’s rule.

Hence, Percent of $(\mathrm{C}+\mathrm{G})=20+20=40 \%$

So, $100=40+(\mathrm{A}+\mathrm{T})$

$(A+T)=100-40=60 \%$

Hence, $\mathrm{A}$ is $30 \%$ and $\mathrm{T}$ is $30 \%$.

Therefore, the calculated percentage of adenine in DNA would be $30 \%$ if $20 \%$ of cytosine is present in DNA.

Question 3. If the sequence of one strand of DNA is written as follows: 5’ATGCATGCATGCATGCATGCATGC-3′ Write down the sequence of the complementary strand in the $3^{\prime} \rightarrow 5^{\prime}$ direction.

Solution. The $3^{\prime} \rightarrow 5^{\prime}$ direction of the sequence of the complementary strand is:

3′-TACGTACGTACGTACGTACGTACGTACG- $5^{\prime}$

Question 4. If the sequence of the coding strand in a transcription unit is written as follows: $5^{\prime}$ ATGCATGCATGCATGCATGCATGCATGC-3′, write down the sequence of $\mathrm{m}$ RNA.

Solution. During transcription, the template strand ( $3^{\prime} \rightarrow 5$ ‘) of DNA codes for m-RNA and hence the sequence of template strand and m-RNA would be complementary to each other whereas the coding strand $\left(5^{\prime} \rightarrow 3^{\prime}\right)$ of DNA will be same as m-RNA (except that $\mathrm{T}$ is replaced by $\mathrm{U}$ in m-RNA).

Here, the sequence of a coding given is:

5′-ATGCATGCATGCATGCATGCATGCATGC-3′

Hence, the sequence of m-RNA would be:

5′-AUGCAUGCAUGCAUGCAUGCAUGCAUGC-3′

Question 5. Which property of DNA double helix led Watson and Crick to hypothesise the semi-conservative model of DNA replication? Explain.

Solution. The nitrogenous bases form a complementary pair between the two polynucleotide chains of DNA was observed by Watson and Crick. Based on the X-ray diffraction data, they proposed that DNA consists of a double helix of two chains with nitrogen bases on the inside and sugar-phosphate on the outside.

Then, they proposed that the two chains are antiparallel with $5^{\prime}-3$ ‘ orientation of the other. The appearance of the two chains is like that of a rope ladder twisted helically with rigid steps twisted into a spiral.

This property of a double helix model of DNA led them to hypothesise the semiconservative model of DNA replication, where the two strands separate and act as a template for the synthesis of a new complementary strand, individually. Consequently, each daughter DNA molecule would have one parental strand and one newly synthesized daughter strand. As only one parental strand is conserved in each daughter molecule, it is called a “semi-conservative mode of replication”.

Question 6. Depending on the chemical nature of the template (DNA or RNA) and the nature of nucleic acids synthesized from it (DNA or RNA), list the types of nucleic acid polymerases.

Solution. The list of the types of nucleic acid polymerases are as following:

(A) DNA-dependent DNA polymerase: It uses a DNA template to catalyze the polymerization deoxynucleotides for synthesising a new DNA strand.

(B) DNA-dependent RNA polymerase: It uses a DNA template strand for synthesising RNA.

Question 7. How did Hershey and Chase differentiate between DNA and protein in their experiment while proving that DNA is the genetic material?

Solution. Alfred Hershey and Martha Chase in 1952 performed their experiments on bacteriophages. These are the viruses which infect bacteria. The bacteriophage infects the bacteria by entering the genetic material into the bacteria. The viral genetic material becomes a part of the bacterial cell which produces further viral particles.

Aim of the experiment was to find out whether protein or DNA entered the bacteria.

Virus particles were grown on medium containing radioactive sulfur and radioactive phosphorus as sulfur was the part of protein and phosphorus was the part of DNA.

Procedure:

The steps of the experiments are as following:

Infection: The bacteriophage were made to infect the bacteria.

Blending: The viral coats were removed by agitating in the blender.

Centrifugation: The viral particles were separated from the bacteria by spinning in a centrifuge.

Observation: It was observed that the bacteria contained radioactive phosphorus while the radioactive sulfur was found in the protein coat of the virus.

Conclusion: It was concluded that it was DNA from the virus which entered the bacterial cells. Hence, it is the DNA which forms the genetic material and gets transferred from one generation to another.

The Hershey – Chase experiment

Question 8. Differentiate between the following:

(A) Repetitive DNA and Satellite DNA

(B) mRNA and tRNA

(C) Template strand and Coding strand

Solution. (A)

(B)

(C)

Question 9. List two essential roles for a ribosome during translation.

Solution. The following essential roles for a ribosome during translation are:

(i) During translation, ribosome binds to mRNA and provides a platform for joining of amino acids.

(ii) During the process of translation, the ribosome also acts as a catalyst for the formation of a peptide bond.

Question 10. In the medium where $E$. coli was growing, lactose was added, which induced the lac operon. Then why does lac operon shut down sometime after the addition of lactose to the medium?

Solution. After adding lactose in the medium where E.coli was growing, the betagalactosidase enzyme is synthesised in $E . c o l i$. This enzyme hydrolyses lactose into galactose and glucose. These sugars are used by bacteria use as a source of energy. In the absence of lactose, the regulatory gene produces a repressor protein which binds on the operator gene and makes it inactive. This prevents RNA polymerase from transcribing the operon. Therefore, lac operon shuts down sometime after the addition of lactose in the medium.

Question 11. Explain (in one or two lines) the function of the following:

(A) Promoter

(B) tRNA

(C) Exons

Solution. (A) Promoter: Promoter is present in the 5 ‘ region of the coding strand of the DNA. It is the region of the DNA which contains certain conserved sequences. The sigma unit of RNA polymerase identifies these conserved sequences. Later causing the binding of RNA polymerase.

(B) t-RNA: t-RNA is referred to as the transfer RNA. It has a major role during the process of translation. It reads the genetic code and carries the amino acid which is required by the -RNA for translation.

(C) Exon: Human genome has split gene arrangement it has the region of the hn- RNA which codes for the protein is referred to as exon whereas the region which does not code for anything is known as introns.

Question 12. Why is the Human Genome Project called a mega project?

Solution. The aim of the human genome project was to sequence $3 \times 10^{9} \mathrm{bp}$ of the human genome. The estimated cost of the project was 9 billion US dollar (3 US dollar per base pair). The database required to store the information of DNA sequence from a single cell was estimated to be 3300 books ( estimating 1000 pages per book and per page having 1000 letters). The enormous amount of data expected to be generated required high-speed computational devices for data storage and retrieval, and analysis. Hence, considering the requirement and the magnitude of the project, it was called a mega project.

Question 13. What is DNA fingerprinting? Mention its application. Solution. DNA Fingerprinting is a technique which is used to find out the variations in individuals of a population at the DNA level. It works on the principle of polymorphism in the DNA sequences.

The applications of DNA fingerprinting are as follows:

It used in establishing a connection in the family

It helps in solving disputes regarding paternity.

It is used in forensic science.

It helps in tracing the evolutionary relationship between the organisms.

Question 14. Briefly describe the following:

(A) Transcription

(B) Polymorphism

(C) Translation

(D) Bioinformatics

Solution. (A) Transcription is a process in which mRNA is synthesised from doublestranded DNA. It takes place in the cytoplasm in case of prokaryotes, and it occurs in the nucleus in case of eukaryotes. The first step of transcription is initiation. In this step, the sigma unit of RNA polymerase identifies the Promoter region in the DNA. The RNA polymerase binds to the DNA and carries out the addition of nucleotides to the RNA this process is referred to as elongation. When the messenger RNA is fully synthesised, the final termination is caused by rho protein. This protein has helicase activity and causes the termination of the RNA-DNA hybrid.

(B) Polymorphism refers to change at the genetic level, which arises due to mutations. The allele sequence variation is called DNA polymorphism if more than one variant at a locus occurs in the human population. As mutations in these sequences may not have any immediate effect, the probability of such variation to be observed in a non-coding DNA sequence is higher. It has an important role in evolution and speciation. These mutations keep on accumulating in each generation and form one of the bases of polymorphism.

(C) The translation is a process of polymerisation of amino acids to form a polypeptide. Messenger RNA, transfer RNA, and ribosomal RNA participates in the process of translation. Messenger RNA provides the sequence for amino acids in the form of codons. Transfer RNA brings the amino acids and forms the peptide bond. Ribosomal RNA forms the entire translation machinery and initiate the process of translation. Further, the elongation takes place by the addition of amino acids followed by termination upon completion of polypeptide chain formation.

(D) Bioinformatics is a branch of science which uses computation to extract the information about the biological data. The use of computational device helps in the collection, storage, retrieval and analysis of the data.

format: plain


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Being Early is No Better than Being Wrong

Castlight Health (CSLT) surged from $10.06 to$15.6 in just four days after Seeking Alpha wrote a pretty damning hit piece on it.

Here’s what’s really stupid. I thought I would bet against at what the time was a 43% gain, but I was early. It became a 60% gain and now I have a $300 loss on my P&L -even after it went up 45%, as if that wasn’t enough. I only bought 9 deep in the money puts and went long 400 shares. I went long shares to cancel out some of the delta from the puts after the trade began to turn against me. Had I just shorted the common stock the day of the Seeking Alpha article I would have lost all my money after getting a margin call. Had I bought puts I would have lost maybe 20-40% depending on the strike and expiration, but it still would have been pretty bad. I’m still bearish on Castlight Health because the fundamentals look poor and the price is way over-extended, but timing is everything. Robert Shiller says bubbles can be predicted; profiting off them is a test of timing and psychology- not being too early and not getting scared and closing the trade too soon. For this very reason, only a tiny, tiny number of people made money shorting grossly overvalued tech stocks at the turn of the century and the same goes for the crash of 2008. Everyone else either missed it or got stopped out because they were too early. But on the other hand, being too late won’t help either. In the second law of thermodynamics no energy can be extracted from a system with maximum entropy. In the stock market, certainty is analogous to entropy in physics. Once it’s incontrovertible a company is insolvent (i.e. cancellation of the common shares) or acquired (i.e. common shares accreted by suitor) the market as a real-time mechanism for gauging uncertainty ceases to exist and hence no profits can be made. Entropy can also be manifested in the volatility, with higher entropy corresponding to lower volatility. Thus, making money in the stock market boils down to betting on an orderly system becoming disorderly or a disorderly system becoming orderly. What do you think will make an option trader more money? Betting$1000 on Facebook falling 4% in one day or Walmart falling 4% in one day? The later because it’s a much less expected event. The more stable people think something is, the greater the returns can be realized when it becomes unstable. A failed merger, for example, can net option speculators returns of over 100x overnight because it’s very rare occurrence. Buying put options on Bank of America in 2007 was very profitable because at the time it was inconceivable the bank could fail. So why didn’t people do this? A few did, but most were oblivious. But for more technical reasons, option traders typically lose money if nothing happens; enough bets and you will lose all your money should the stock not fall or rise enough, depending on your strike price and time until expiration.

Profitable strategies will be discussed in later blog posts.


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## Evaluating Algebraic Expressions

### Learning Outcomes

• Evaluate an expression for a given value

## Evaluate Algebraic Expressions

In the last section, we simplified expressions using the order of operations. In this section, we’ll evaluate expressions—again following the order of operations.

To evaluate an expression, we substitute the given number for the variable in the expression and then simplify the expression using the order of operations.

### example

Evaluate $x+7$ when

1. $x=3$
2. $x=12$

Solution:

1. To evaluate, substitute $3$ for $x$ in the expression, and then simplify.

 $x+7$ Substitute. $\color{red}{3}+7$ Add. $10$

When $x=3$, the expression $x+7$ has a value of $10$.
2. To evaluate, substitute $12$ for $x$ in the expression, and then simplify.

 $x+7$ Substitute. $\color{red}{12}+7$ Add. $19$

When $x=12$, the expression $x+7$ has a value of $19$.

Notice that we got different results for parts 1 and 2 even though we started with the same expression. This is because the values used for $x$ were different. When we evaluate an expression, the value varies depending on the value used for the variable.

### example

Evaluate $9x - 2,$ when

1. $x=5$
2. $x=1$

### example

Evaluate ${x}^{2}$ when $x=10$.

### example

$\text{Evaluate }{2}^{x}\text{ when }x=5$.

### example

$\text{Evaluate }3x+4y - 6\text{ when }x=10\text{ and }y=2$.

### example

$\text{Evaluate }2{x}^{2}+3x+8\text{ when }x=4$.

### try it

In the video below we show more examples of how to substitute a value for variable in an expression, then evaluate the expression.


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# Proof involving sums

## Homework Statement

Prove that $$\sum_{k=0}^{l} \binom{n}{k} \binom{m}{l-k} = \binom{n+m}{l}$$

## Homework Equations

If $$a$$ and $$b$$ are any numbers and $$n$$ is a natural number, then $$(a+b)^{n}=\sum_{j=0}^{n} \binom{n}{j} a^{n-j}b^{j}$$

## The Attempt at a Solution

I know that $$(1+x)^{n}(1+x)^{m}=(1+x)^{n+m}$$ so that $$\sum_{k=0}^{n} \binom{n}{k}x^{k} \cdot \sum_{j=0}^{m} \binom{m}{j}x^{j} = \sum_{l=0}^{n+m} \binom{n+m}{l}x^{n+m}$$

If I let $$j=l-k$$, then I get $$\sum_{k=0}^{n} \binom{n}{k}x^{k} \cdot \sum_{l=k}^{m+k} \binom{m}{l-k}x^{l-k} = \sum_{l=0}^{n+m} \binom{n+m}{l}x^{n+m}$$

I can see that I'm close to the desired result--I'm just having trouble understanding how to get to it.

Dick
Homework Helper
You have some index problems. In your final solution l is a dummy index (twice). In your original problem it's not. If you fix this I think you will see the solution. You aren't as close as you think, nor are you as far away as you think.

Last edited:
Dick
Homework Helper
The dummy problem is coming because when you set l=j+k you are actually saying 'pick the x^l term' from the right side (where the power of x should have been x^l, not x^(n+m)). Since you are selecting a specific l, the sum goes away on the right. The constrain l=j+k will also get rid of one of the sums on the left.

OK, so I am picking a specific value for l by choosing l=j+k, although this still seems a little strange to me, since I am summing over j and k on the LHS. Is it kind of like a function where I input two values (some j and some k) on the LHS, giving me a value on the RHS?

I can see that two of the sums will disappear. I think this leaves me with:
$$\sum_{k=0}^{n} \binom{n}{k} \binom{m}{l-k} x^{l} = \binom{n+m}{l}x^{l}$$

I'm still having trouble seeing why my final sum runs from 0 to l.

Dick


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## error mirroring from novell.com

Hi,

when mirroring the channels "oes" and "sles-9-i586" from novell.com the following errors occur quite regularly:

Error: An error occurred while trying to add the patch "patch-10455" to the bundle "/Bundles/Novell/SLES/9/patch-10455". (com.novell.zenworks.zlman.services.pkgmgt.admin.D ataStoreFault={})

Error: An error occurred while trying to add a package to the bundle "/Bundles/Novell/OES/1/oes-bundle". (com.novell.zenworks.zlman.services.pkgmgt.admin.U pdateFailureFault={})

running zlmmirror again and again sometimes helps, sometimes not. Anyone else seeing this? Any ideas what to do about it?

Thanks, Lothar
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