118438283
Spontaneous symmetry breaking and the Cabibbo angle
SummaryWe study the possibility that the magnitude and direction of the strong breaking ofSU3 may be obtained from a self-consistent response equation, symmetric inSU3 apart from driving terms. These driving terms may be eithera), direct: a relatively strong force corresponding to the fifth interaction, orb) indirect: small perturbations due to electromagnetic and appropriate weak interactions. In the latter case, choosing a model in which the nonleptonic decays have a characteristic angle twice that of the semi-leptonic decays, one obtains the value

$$\tfrac{1}{2}\cos ^{ - 1} (\sqrt 3 /2) = 15^ \circ $$

 for the Cabibbo angle.RiassuntoSi studia la possibilità di ottenere l’intensità e la direzione della rottura forte diSU3 da una equazione di risposta autocoerente, simmetrica inSU3 indipendentemente dai termini fondamentali. Questi termini fondamentali possono esere siaa) diretti: una forza relativamente forte corrispondente alla quinta interazione, ob) indiretti: piccole perturbazioni dovute ad interazioni elettromagnetiche deboli ed appropriate. Nell'ultimo caso, scegliendo un modello in cui i decadimenti non leptonici hanno un angolo caratteristico doppio di quello dei decadimenti semileptonici, si ottiene il valore di

$$\tfrac{1}{2}\cos ^{ - 1} (\sqrt 3 /2) = 15^ \circ $$

 per l’angolo di Cabibbo.РезюмеМы изучаем возможность, что величина и направление сильного нарушенияSU3 могут быть получены из само-согласованного характеристического уравнения, симметричного вSU3, за иа исключением главных членов. Эти главные члены могут быть либо a)прямыми: относительно сильная сила, соответствующая Пятому Взаимодействию, либо б) непрямыми: слабые возмущения, обусловленные электромагинтным и соответствующим слабым взаимодействиями. В последнем случае, выбирая модель, в которой нелептонные распады имеют характеристический угол в два раза болясий, чем для полу-лептонных распадов, получаем величину

$$\tfrac{1}{2}\cos ^{ - 1} (\sqrt 3 /2) = 15^ \circ $$

 для угла Кабиббо.
121551361
Chiral symmetry and the goldstone theorem
13202889
Optimal signal-to-quantum noise ratio for nonclassical number states
Abstract We analyze the properties of nonclassical number states, specifically squeezed number states D ( α ) S ( z )| n 〉, and find their maximum signal-to-quantum noise ratio. It is shown that the optimal signal-to-quantum noise ratio for these states decreases as 1/(2 n +1) 2 , where n is the photon number, from the optimal value as derived by Yuen [Phys. Lett. A 56 (1976) 105].
119711153
Dynamical group model of the CDW state
Abstract The dynamical group for a one-dimensional model of a many-electron system exhibiting a charge-density wave is obtained. The corresponding Lie algebra in a physical model is U(2); it is used to obtain the spectrum and coherent ground state, and to define a corresponding order parameter.
27515895
Generalized Holstein-Primakoff squeezed states for SU(n).
We show how to define multiphoton, many-mode squeezed states for SU(n), using a generalized Holstein-Primakoff realization. We prove that for the class of realizations given, the resulting squeezing reduces to that of SU(2), and exemplify with a specific calculation for SU(3).
12865240
An interface between physics and number theory
We extend the Hopf algebra description of a simple quantum system given previously, to a more elaborate Hopf algebra, which is rich enough to encompass that related to a description of perturbative quantum field theory (pQFT). This provides a mathematical route from an algebraic description of non-relativistic, non-field theoretic quantum statistical mechanics to one of relativistic quantum field theory. Such a description necessarily involves treating the algebra of polyzeta functions, extensions of the Riemann Zeta function, since these occur naturally in pQFT. This provides a link between physics, algebra and number theory. As a by-product of this approach, we are led to indicate inter alia a basis for concluding that the Euler gamma constant γ may be rational.
9242923
INTERPRETING THE EVOLUTION OF THE SIZE-LUMINOSITY RELATION FOR DISK GALAXIES FROM REDSHIFT 1 TO THE PRESENT
A sample of very high resolution cosmological disk galaxy simulations is used to investigate the evolution of galaxy disk sizes back to redshift 1 within the ΛCDM cosmology. Artificial images in the rest-frame B band are generated, allowing for a measurement of disk scale lengths using surface brightness profiles as observations would, and avoiding any assumption that light must follow mass as previous models have assumed. We demonstrate that these simulated disks are an excellent match to the observed magnitude-size relation for both local disks and for disks at z = 1 in the magnitude/mass range of overlap. We disentangle the evolution seen in the population as a whole from the evolution of individual disk galaxies. In agreement with observations, our simulated disks undergo roughly 1.5 mag arcsec^(–2) of surface brightness dimming since z = 1. We find evidence that evolution in the magnitude-size plane varies by mass, such that galaxies with M_* ≥ 10^9 M_⊙ undergo more evolution in size than luminosity, while dwarf galaxies tend to evolve potentially more in luminosity. The disks grow in such a way as to stay on roughly the same stellar-mass-size relation with time. Finally, due to an evolving stellar-mass-star-formation-rate (SFR) relation, a galaxy at a given stellar mass (or size) at z = 1 will reside in a more massive halo and have a higher SFR, and thus a higher luminosity, than a counterpart of the same stellar mass at z = 0.