The meaning of general covariance of einstein’s theory of gravity

The fundamental symmetry of Einstein’s theory of gravity is Lorentz-invariance which leads to a well defined energy-momentum tensor. This is also true for Maxwell’s theory of electromagnetism which has an additional symmetry due to its spin one, restmass zero character. Similarly, the spin two, restmass zero character of the gravitational field leads to an additional gauge symmetry that happens to be isomorphic to the concept of general covariance. The gauge-covariant energy-momentum tensor for gravitational interactions vanishes identically.     

Ambiguous solutions of supersymmetric theories

An examination is made of supersymmetric theories which have a variety of physically inequivalent solutions in zeroth order. For any theory in which the supersymmetry itself is not spontaneously broken, the potential remains zero in the one-loop approximation at all supersymmetric values of the scalar fields, so the ambiguities present in zeroth order are not resolved by higher-order corrections. In one interesting class of models, these ambiguities include a re-scaling of all fields; there is a corresponding pseudo-Goldstone boson whose mass remains zero to all orders, even though the theory is not scale-invariant.     

Anomalies,field transformations,and the relation between SU(4) and SO(4) supergravity

We examine at the one-loop level the equivalence between SU(4) and SO(4) supergravity by calculating some amplitudes which are zero in SO(4) theory but may not be zero in SU(4) theory. The results of the calculation show that the theories are not equivalent and global supersymmetry is violated unless certain finite counter terms are introduced.     

Static dust sphere in Einstein-Cartan theory

Physically meaningful solutions of the field equations for static spherical dust distributions in the Einstein-Cartan theory have been obtained. There is one in which the spin is zero at the center and another with zero spin at the boundary of the sphere.     

无光焦度校正器和单一反射镜组成的光学系统

从三级像差理论出发分析了由两透镜无光焦度校正器和单一反射镜组成的光学系统，讨论两透镜无光焦度校正器放置在单一反射镜前和后组成的光学系统的各种消像差条件。并给出求解两透镜无光焦度校正器参量的计算公式。     

Can correlations drive a band insulator metallic?

We analyze the effects of the on-site Coulomb repulsion U on a band insulator using dynamical mean field theory (DMFT). We find the surprising result that the gap is suppressed to zero at a critical Uc1 and remains zero within a metallic phase. At a larger Uc2 there is a second transition from the metal to a Mott insulator, in which the gap increases with increasing U. These results are qualitatively different from Hartree-Fock theory which gives a monotonically decreasing but nonzero insulating gap for all finite U.     

A model non-local field theory with some causal properties of a dual theory

We present a simple field theory which reproduces the singularity structure associated with acausality of the planar dual loop. The field theory differs fundamentally from a conventional non-local theory in that (in the tree approximation) the elementary length is independent of the order of interaction, and, on renormalisation, can become zero.     

Three Slit Experiments and the Structure of Quantum Theory

In spite of the interference manifested in the double-slit experiment, quantum theory predicts that a measure of interference defined by Sorkin and involving various outcome probabilities from an experiment with three slits, is identically zero. We adapt Sorkin’s measure into a general operational probabilistic framework for physical theories, and then study its relationship to the structure of quantum theory. In particular, we characterize the class of probabilistic theories for which the interference measure is zero as ones in which it is possible to fully determine the state of a system via specific sets of ‘two-slit’ experiments.     

On the “overlapping resonances” concept of acoustic transmission through an elastic plate,II: Numerical examples and physical implications

In a companion paper [1] the Fiorito, Madigosky and Überall approximate theory of transmittivity of an infinite, isotropic, elastic plate in terms of Lamb mode resonances [2] is examined, and extended by validating coherent addition of these overlapping resonances. The present paper provides numerical and heuristic tests which yield convincing proof of the applicability of the overlapping resonances concept. At various thicknesses of a water-immersed, steel plate, including the half-space and zero thickness limits, the behaviour is shown to be compatible with known exact behaviour. Overlapping resonances explain the reduction towards zero of the transmittivity near the coincidence angles of the zero order Lamb modes as these converge to the Rayleigh angle. Contrary to earlier interpretations, both zero order modes survive at the half-space limit. The A₀ mode is shown to contribute below (fd)_critical, becoming then highly damped and, effectively, non-propagating. The interpretation provided of the transition of the A₀ mode in this region bridges the gap between conventional Lamb mode theory and thin plate theory.     

有限温度场论单粒子不可约图形的零动量行为

本文利用闭路Green函数理论讨论了有限温度场论单粒子不可约(1PI)图形的零动量行为,并且证明在体现Kubo-Martin-Schwinser条件的“│P₀│方案”下,这种图形的推迟函数的零动量极限是完全确定的。 关键词：     

Instanton-centred expansions and elimination of zero modes

A general method of saddle-point expansions proposed on a basis of simple geometrical ideas allows us to avoid zero modes and develop a perturbation theory around a degenerate classical solution. Application to the Yang-Mills theory results in an instanton-centered perturbation theory in which the gluon propagator reduces to the scalar one. The BRST symmetry is extended to the instanton sector.     

Negative energy,debts, and disinformation from the viewpoint of analytic number theory

The number zero and negative numbers are added to analytical number theory which includes transcendents. New solutions of Diophantine equations are applied to thermodynamics, information theory and biology.     

物理学中的示零实验

示零实验采用完全补偿法 ,在物理实验中具有独特的作用 .本文介绍了示零实验在提高测量精度、修正系统误差和为理论提供依据方面的特殊功能     

A new type of second-order phase transition derived from Devonshire's theory of ferroelectrics

Including external fields Devonshire's theory of ferroelectric phase transitions leads to a type of second-order transitions for which the order parameter is different from zero below and aboveT _c . Although in a certain limiting case the order parameter becomes zero aboveT _c the resulting theory is nevertheless different from the usual Landau-theory suggesting the existence of different types of systems undergoing second-order phase transitions.     

Bosonic zero modes in discretized light-cone field theory

It is shown that for theories with bosonic fields a constrained zero mode is a necessary ingredient for a consistent discretized light-cone quantization (DLCQ). Inclusion of this zero mode is shown to remove a non-covariant, quadratically divergent contribution to the fermion self-energy in 3+1 dimensional Yukawa theory which would otherwise be present. It is further shown to result in a fully consistent set of Heisenberg equations. The possibility of maintaining parity in DLCQ is discussed.     

Vanishing three-loop beta function in N = 4 supersymmetric Yang-Mills theory

We have calculated the beta function of the N = 4 supersymmetric Yang-Mills theory through three-loop order and find that it is zero. The calculation was performed using superspace techniques that also allowed the calculation of the complete three-loop chiral-multiplet propagator, which turned out to be quite simple. These results strongly support the speculations that the theory is finite order-by-order in perturbation theory.     

Weber electrodynamics,part II unipolar induction,Z-antenna

Weber electrodynamics predicts the localized unipolar induction observed by Müller and Kennard; whereas the Maxwell theory, based upon closed current loops and the flux rule, fails. The Weber theory for high frequency fields predicts a zero self torque on the Pappas-Vaughan Z-antenna, as observed. In contrast, the Maxwell theory predicts a sizeable self torque which is not observed.     

The vanishing viscosity limit for a dyadic model

A dyadic shell model for the Navier-Stokes equations is studied in the context of turbulence. The model is an infinite nonlinearly coupled system of ODEs. It is proved that the unique fixed point is a global attractor, which converges to the global attractor of the inviscid system as viscosity goes to zero. This implies that the average dissipation rate for the viscous system converges to the anomalous dissipation rate for the inviscid system (which is positive) as viscosity goes to zero. This phenomenon is called the dissipation anomaly predicted by Kolmogorov’s theory for the actual Navier-Stokes equations.     

Dual models and the geometry of space-time

The zero slope limit of the closed string sector of a dual model yields a Lagrangian theory in which space-time has a non-Riemannian geometry. We find that there is torsion but no homothetic curvature.     

An inverse spectral analysis of transmission problem in thermo- and photo-acoustic tomography

We study an inverse spectral theory in the thermo- and photo-acoustic tomography in imaging science. Under certain non-trapping hypothesis, we study the zero set of the Fourier transform of the observation data. The zero set corresponds to the spectrum of the interior transmission problem. We reduce the problem into an interior transformation problem of two indices of refractions. The inverse spectral problem is to study the inverse uniqueness of the indices of refraction. The zero distribution theory of entire function plays a role.