Annals of Physics最新文献

The continued interest in placing bounds on the neutron’s Electric Dipole Moment (EDM) is due to the implications regarding the characteristics of the strong interaction and, in particular, its behavior under the CP symmetry. In this work, we discuss the apparent tension resulting from the discrepancy of about 13 orders of magnitude between the current bounds and the expected quantum uncertainty in the relevant quantity. We offer a resolution of the “puzzle” in terms of the notion of a weak measurement, using a version of the corresponding formalism adapted to consideration of the nEDM experiment at the Spallation Neutron Source at the Oak Ridge National Laboratory.

The rigorous formula of overlap integrals of continuum stationary states with their asymptotic expressions in potentials of finite widths are derived. Those of energies $E_1$ and $E_2$ consist of diagonal terms that are proportional to $\delta (E_1-E_2)$ and nondiagonal terms. Owing to the composition of nondiagonal terms, superpositions of stationary states have time-dependent norms and finite probability currents. These do not represent isolate states. In various exceptional potentials and in free theory, nondiagonal terms do not exist, and the superpositions of states with different energies represent isolate particles that exactly describe scattering processes.

In this paper we investigate the statistical mechanics within the Linear–Quadratic GUP (LQGUP, i.e, GUP with linear and quadratic terms in momentum) models in the semiclassical regime. Then, some thermodynamic properties of a system of 3-dimensional harmonic oscillators are investigated by calculating the deformed partition functions. According to the equipartition theorem, we show that the number of accessible microstates decreases sharply in the very high temperatures regime. When the thermal de Broglie wavelength is of the order of the Planck length, three degrees of freedom are frozen in this setup. In other words, it is observed that there is an effective reduction of the degrees of freedom from 6 to 3 for a system of 3D harmonic oscillators in this framework. The calculations are carried out using both approximate analytical and exact numerical methods. The results of the analytical method are also presented in the form of thermal wavelengths for better understanding. Finally, the case of a 2-dimensional harmonic is treated as another example to comprehend the results, leading to a reduction of the degrees of freedom from 4 to 2.

We explore the holographic phase transition with logarithmic nonlinear electrodynamics in the backgrounds of the AdS soliton away from the probe limit. We disclose the properties of phases by the holographic entanglement entropy of disk for the scalar operators. We find that the holographic entanglement entropy is a useful tool to probe the critical chemical potential and the order of the phase transition in the system. In the superconductor phase, the holographic entanglement entropy for scalar operator $<O_{+}>$ has a non-monotonic behavior as the chemical potential increases, while the entanglement entropy for operator $<O_{-}>$ decreases monotonously. With the increase of the logarithmic nonlinear factor b, the holographic entanglement entropy becomes bigger for both scalar operators $<O_{\pm }>$. Furthermore, the insulator/superconductor phase transition probed by the entanglement entropy in the holographic system is characterized only by the chemical potential and is independent of the logarithmic nonlinear electrodynamics.

The primary objective of this study is to introduce field-theoretical tools into the realm of physical properties within planar systems exhibiting possible anisotropic features. This goal is achieved by fitting a specific field-theoretical model to simulate the presence of such a system. The proposed approach enables the investigation of in-plane physical phenomena using analytic methods. Specifically, our focus is on phenomena related to stationary point-like field sources that can mimic defects in material layers. We employ a dimensional reduction procedure on the well-known Carroll–Field–Jackiw model to derive a planar theory. This theory includes an electromagnetic sector governed by Maxwell-Chern–Simons electrodynamics, a scalar sector described by a massless Klein–Gordon field, and a mixed sector where the background vector controls the interactions between the scalar and gauge fields. Across all sectors of this planar theory, we explore physical phenomena arising from interactions with external sources. Specifically, we analyze perturbative effects up to second order in the background vector, examining contributions from both electric and scalar planar charges as well as Dirac points.

Assuming that the geometry of spacetime is uniquely determined by the energy–momentum tensor of matter alone, i.e. without any interactions, enables us to construct the Lagrangian from which the metric of higher dimensional spacetime follows. From the geodesic equations that follow, it becomes clear that the incorrect mass of elementary particles predicted by Kaluza–Klein theories arises from the assumption that in the absence of gravity the solution to the Einstein field equations reduces to the Minkowski metric. From construction of a consistent theory of $4D$ electromagnetism, we find that this assumption does not only result in the incorrect mass of elementary particles, but also the incorrect value of the cosmological constant. This suggests that these incorrect predictions, which are often regarded as major flaws of Kaluza–Klein theories, just reflect the inconsistency of the assumption that the solution to Einstein field equations reduces to Minkowski metric in the absence of gravity and Weyl invariance which is the symmetry of gauge theories in $4D$ spacetime. Abandoning this assumption results in modification of general relativity. We show that the unified description of fundamental interactions naturally incorporates the Higgs mechanism. For non-Abelian gauge fields, we find that the manifold comprising the extra dimensions has to be a group manifold and show that the standard model is realized in 16$D$ spacetime. We show that charge and spin are the same concept, but what makes them different is that the former follows from symmetry of $4D$ spacetime while the latter follows from symmetry of the internal space.

$p$-Adic quantum mechanics is constructed from the Dirac–von Neumann axioms identifying quantum states with square-integrable functions on the $N$-dimensional $p$-adic space, $Q_p^N$. This choice is equivalent to the hypothesis of the discreteness of the space. The time is assumed to be a real variable. The $p$-adic quantum mechanics is motivated by the question: what happens with the standard quantum mechanics if the space has a discrete nature? The time evolution of a quantum state is controlled by a nonlocal Schrödinger equation obtained from a $p$-adic heat equation by a temporal Wick rotation. This $p$-adic heat equation describes a particle performing a random motion in $Q_p^N$. The Hamiltonian is a nonlocal operator; thus, the Schrödinger equation describes the evolution of a quantum state under nonlocal interactions. In this framework, the Schrödinger equation admits complex-valued plane wave solutions, which we interpret as $p$-adic de Broglie waves. These mathematical waves have all wavelength $p^{-1}$. In the $p$-adic framework, the double-slit experiment cannot be explained using the interference of the de Broglie waves. The wavefunctions can be represented as convergent series in the de Broglie waves, but the $p$-adic de Broglie waves are just mathematical objects. Only the square of the modulus of a wave function has a physical meaning as a time-dependent probability density. These probability densities exhibit interference patterns similar to the ones produced by ‘quantum waves’. In the $p$-adic framework, in the double-slit experiment, each particle goes through one slit only. The $p$-adic quantum mechanics is an analog (or model) of the standard one under the hypothesis of the existence of a Planck length. The precise connection between these two theories is an open problem. Finally, we propose the conjecture that the classical de Broglie wave-particle duality is a manifestation of the discreteness of space–time.

Thermodynamically stable low-temperature phases of the Bose–Fermi mixtures composed of bosons and spinless fermions close to four dimensions are considered. In the regime, where the only boson–fermion two-body interaction is present and tuned to unitary limit, the properties of a system solely depend on the mass and number ratios of constituent atoms. In addition to the phase with the dimers (boson–fermion shallow bound states), we identified one more state of the mixture with the coexistence of fermionic dimers and trimers. The universal physics of these phases, whose characteristic feature is an absence of the Bose–Einstein condensate, is discussed.

The analysis of empirical data through model-free inequalities leads to the conclusion that violations of Bell-type inequalities by empirical data cannot have any significance unless one believes that the universe operates according to the rules of a mathematical model.

The quantum theory of black holes has opened up a window to study the intersection of general relativity and quantum field theory, but perceived paradoxes concerning the fate of classical information directed at a black hole horizon, as well as concerning the unitarity of the evaporation process, have led researchers to question the very foundations of physics. In this pedagogical review I clarify the ramifications of the fact that black holes not only emit radiation spontaneously, but also respond to infalling matter and radiation by emitting approximate clones of those fields in a stimulated manner. I review early purely statistical arguments based on Einstein’s treatment of black bodies, and then show that the Holevo capacity of the black hole (the capacity to transmit classical information through a quantum channel) is always positive. I then show how stimulated emission turns the black hole into an almost optimal quantum cloning machine, and furthermore discuss the capacity of black holes to transmit quantum information. Taking advantage of an analogy between black hole physics and non-linear optics I show that a calculation of the evolution of a black hole over time, using a discretization of the black hole $S$-matrix path integral, yields well-behaved Page curves suggesting that black hole evaporation is unitary. Finally, I speculate about possible observable consequences of stimulated emission of radiation in black holes.