quantum physics is no simple subject to
explain or attempt to even comprehend
quantum computers are no different
nevertheless this is your by popular
demand
here is how a quantum computer works
trusty whiteboard here and I want order
to explain quantum computers how they
work on a basic level or as basic as I
can possibly make it we have to
understand how the classical computing
system works based on a binary code
using just ones and zeros now imagine a
transistor like a switch I kind of ran
through this in this video here but I'll
go over it again just for those who
haven't watched that video yet so
transistors are essentially switches
this is the open state we'll denote that
as zero and this is the closed state
well denote that as one in this state
here current is allowed to flow and in
the state here current can not so binary
transistors open and close to indicate 1
and 0 and threshold voltage does not
reach a gap in the current is created
indicating a zero for false whether it's
a one or zero really depends on the
algorithm being used they'll always be
opposite so for our examples in this
video one will equal true which equals a
closed circuit and zero equals false
which equals an open circuit this is how
all data and modern computing systems is
transmitted and processed and you can
imagine how multiple switches multiple
transistors billions of them actually in
a single processor opening and closing
billions of times a second can equate to
some serious computational power but
quantum computers make pcs like this one
behind me seem like basic calculators
they aren't binary systems per se
although we often use 1 and 0 to denote
the range of values quantum bits or
qubits can denote the word quantum and
phrases like quantum mechanics and
quantum physics which inherently makes
them sound very daunting literally just
describes the energy states of very
small particles and the reason why we've
only started using this word in the past
when I'll half a century or so it's
because we never had tools small enough
and precise enough to measure the energy
states of things like electrons photons
and even just whole atoms but thanks to
research done by folks like vona
heisenberg serge haroche and david
Weinland we now know that it also
describes how an electron can be in two
places at once this is from where
quantum computing is derived instead of
ones and zeros regular bits qubits can
represent an infant
range of values between one and zero
think of them like probabilities and
unlike the classical counterpart qubits
can be physical objects like electrons
and photons imagine a compass with one
pole denoted one and the other pole
denoted zero the needle of a compass can
swing whenever it wants wherever it
wants within the system but it can never
point to anything higher than one or
lower than zero instead it can point to
areas in between the two poles and
represent the likelihood of either
becoming a 1 or 0 once the qubit is
processed and observed this area in
between is what's known as superposition
when we read and interpret classical
let's say 3 bit binary data streams we
understand that 8 outcomes are possible
since there are only two possible States
and 3 bits to raise to n where n is 3
equals 8 so eight possible outcomes here
and all probabilities of which must
equal one so there's a 100 percent
chance that a 3 bit binary system will
yield one of these values since they're
the only values possible with three
digits and two numbers a quantum three
bit system works a bit different however
since each qubit can denote any complex
number between 0 and 1 then the sum of
the squares of each complex probability
must equal 1 for a 100% probability when
we make a measurement of a 3 bit quantum
system the values of the particles in
each orientation collapsed to a
classical state of binary by the
computational power of a 3 bit quantum
computer far exceeds that of classical
systems where binary systems require to
raise to the power n bits quantum
computers can express the same amount of
information in just in qubits for scale
with just a 30 qubit quantum computer
would be capable of nearly 10 teraflops
of floating operations per second a
process which in today's modern
technology would require billions of
transistors that's pretty awesome but
don't get too excited because the modern
applications of quantum computers are
still yet to be seen in a sense we use
them a lot for like predictions and
probabilities because you can do
multiple operations super fast
parallelism and quantum computers is
insane but to watch a Netflix er watch
YouTube or even I don't know render a
video quantum computers aren't all that
viable yet simply put modern processors
already do a pretty darn good job at
those simple tasks on PCs so it wouldn't
make much sense to replace them which
can be
we're from like 50 bucks to maybe 500
bucks with super expensive multi-million
dollar quantum pcs they don't belong in
your living room they belong into
research laboratories QCs also get
extremely hot and have to be
cryogenically cooled down to roughly
zero Kelvin in most cases they must also
be shielded from the outside world since
even the smallest magnetic disturbances
can offset a qubits reading and promote
2d coherence that's the word you don't
want to hear if you're in the QC
business they're also extremely large
expensive and difficult to maintain the
viability of quantum computers might
change as our infrastructure and
technology does but I still expect we'll
be using binary systems for quite some
time they just work we don't have to
worry about things like quantum
decoherence insane shielding or
overheating No okay maybe a little
overheating but not on the same scale
but much like early binary computers
quantum computers today are very large
who knows in say the next 50 years we
may shrink quantum processors or what
might become quantum processors down to
the size of a modern transistor
processor there are about two billion
transistors in the space a space really
no larger than the surface area of my
thumbnail but imagine 2 billion cubits
in the same space that is insane
computational power that's a lion's mane
I am worried though by about that time I
expect we'll have discovered a true
artificial intelligence which will mean
the end of ourselves basically
terminators roaming everywhere if you
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