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We revisit the basic principle for lasing : Population inversion which is nevertheless closely linked to the negative temperature state in non-equilibrium thermodynamics. With the introduction of quantum degeneracies, we also illustrate their relationship with the lasing via the tuning of population inversion.
A quantum-mechanical formulation of energy transfer between closely-spaced surfaces is given. Coupling between the two surfaces arises from the atomic dipole-dipole interaction involving transverse-photon exchange. The exchange of photons at resonance greatly enhances the radiation transfer. The spacing (distance) dependence is derived for the quantum well - quantum well situation. The interaction between two planar quantum wells, separated by a gap is found to be proportional to the 4th power of the wavelength-to-gapwidth ratio and to the radiation tunneling factor for the evanescent waves. Expressions for the net power transfer, in the near-field regime, from hot to cold surface for this case is given and evaluated for representative materials. Computational modeling of selected, but realizable, emitter and detector structures and materials shows the benefits of both near-field and resonance coupling (e.g., with 0.1 micron gaps).
We probe Penrose's five-fold symmetry and fractal behavior for atom H. With radius r(H) derived from H mass m(H), H symmetry is governed by Euclid's golden ratio phi=0,5(sqrt(5)-1), as proved with accurate H terms. A Hund-type Mexican hat curve in the natural H spectrum points to mirrored antihydrogen Hbar. We predict that term H 1S-3S, to be measured soon, is 2 922 743 278 654 kHz.
We use the power density spectra obtained by fluctuation-enhanced sensing of bacterial odors (Escherichia coli and Anthrax-surrogate Bacillus subtilis) to generate new, highly distinguishable, types of patterns based on the average slope of the spectra in different frequency ranges. Such plots can be considered as "fingerprints" of bacterial odors. Three different ways of pattern generation are tested, including a simple binary version. The obtained patterns are simple enough to identify the situation by the naked eye without a pattern recognizer.
When speaking of the unification of quantum mechanics and relativity, one normally refers to special relativity (SR) or to Einstein general relativity (GR). The Dirac and Klein-Gordon wave equations are an example of unification of quantum concepts and concepts falling within the domain of SR. Current relativistic QFT derives from the transcription of these equations into second quantization formalism. Many researchers hope that the unification of QFT with GR can solve the problems peculiar to QFT (divergences) and to GR (singularities). In this article, a different strategy is proposed, in an informal manner. Firstly, emphasis is laid on the importance of the transaction notion for quantum theories, introduced by Cramer in the eighties and generalized by the author of this article. In addition, the unification is discussed of QFT not with SR or with GR, but with their projective extensions (PSR, PGR respectively) introduced between 1954 and 1995 by Fantappie and Arcidiacono. The existence emerges of new fundamental constants of nature, whose significance is discussed. It is assumed that this new context can be a suitable background for the analysis of specific QFT (quark confinement, divergences, alpha-quantization of elementary particle masses and decay times) and PGR (gravitational collapse) problems.
The astronomical observations indicate that the universe expands with acceleration and it has a finite event horizon. The recent CMB observations confirm the universe is homogeneous, isotropic and asymptotically flat. The total gravitational energy of a body having mass m is the gravitational potential energy originating from the gravitational interaction of the body with all masses of the universe, within the event horizon. The flat geometry of the universe enables to determine the total gravitational energy of the mass m within the framework of the Newtonian gravity in Euclidean space. By this approach, it has been found the modulus of the total gravitational energy of a body is close to its rest energy E = m*c^2, which is a remarkable result. Besides, the smoothed gravitational potential in an arbitrary point of the observable universe appears close to - c^2, where c is the speed of the light.
We theoretically demonstrate that earthquake shield made of seismic crystal can damp down surface waves, which are the most destructive type for constructions. In the paper, seismic crystal is introduced in aspect of band gaps (Stop band) and some design concepts for earthquake and tsunami shielding were discussed in theoretical manner. We observed in our FDTD based 2D elastic wave simulations that proposed earthquake shield could provide about 0.5 reductions in magnitude of surface wave on the Richter scale. This reduction rate in magnitude can considerably reduce destructions in the case of earthquake.
Flavor physics, like cosmology, is likely in need of new basic ideas; the puzzles of elementary particle mass hierarchies and in particular the e-mu-tau and neutrino ones still remain mysteries. In this paper a new idea of dynamical connection between low energy 3-flavor particle mass hierarchies and electroweak charges is studied with restriction to the simplest case of lepton flavor phenomenology. The main inference is that it can be only two types of lepton 3-flavor particle-copy groups: 1) with large and strongly hierarchical mass ratios and 2) with close to 1 mass ratios. From experimental data definitely follows that the three charged leptons belong to the first type whereas the three neutrinos belong to the second type and so are quasi-degenerate. The inferences of QD-neutrinos with realistic small masses and oscillation hierarchy parameter and quark-QD-neutrino mixing angle complementarity follow from the fact of small EW charges and their relation to the concept of benchmark flavor pattern.
We suggest discovery targets for the Higgs boson, dark matter, and quantum gravity mass scales, motivated by the Dirac equation for the electron in deSitter space, and a sixth-order constraint between the electron QED parameters and the cosmological constant. We go on to show that this constraint can be viewed as a structural parameter of the electron, and leads naturally to a new cosmic horizon. A dual fourth-order constraint implies a second-order one, from which the electron neutrino mass is derived.
Lev Davidovich Landau was arguably one of the greatest and most versatile physicists. His work spans a very wide range and has had a considerable impact on all areas of physics including condensed matter physics, plasma, high energy and particle physics, fluid dynamics, astrophysics, gravitation, elasticity, etc. Along with his former fellow student, E Lifshitz, he wrote the set of a dozen volumes, the magnificent world-renowned Course of Theoretical Physics which covered topics ranging from mechanics, classical theory of fields, quantum mechanics, electrodynamics of continuous media, fluid dynamics, kinetic theory, theory of elasticity, statistical physics and more.
First, the description of a quantization local electromagnetic field is proposed by presentation of quantum form of Maxwell equations in the vacuum which describes the electromagnetic field by the model of a Bose-gas consisting of the interacting fundamental neutral Bose-particles (light bosons) with spin one and a finite mass $m$. The later represents as a fundamental constant $ m=2.4 \cdot 10^{-35} kg $. The light bosons of electromagnetic field induce the Bose-excitations, which are the photon modes. In this letter, we show that the Bose gas of light bosons undergoes a phase transition at low temperatures to condition in which the zero-momentum quantum state is occupied by a finite fraction of the light bosons. This momentum-condensed phase represents as a superfluid component for electromagnetic field. The later is absent at the transition temperature, which is found in this letter.
A solution to the dark matter problem is set forth in the framework of reductive semiclassical gravity, i.e., semiclassical gravity involving quantum state reduction. In that theory, the Einstein equation includes the energy-momentum tensor originating from pseudomatter and partially compensating for quantum jumps of the matter energy-momentum tensor. The compensation ensures the continuity of metric and of its first time derivative. Pseudomatter is actualized as pseudodust and perceived as a dark matter. The necessity of compensating for quantum jumps makes pseudomatter, i.e., dark matter of such a form, an indispensable rather than ad hoc element of the theory. Applications: The Schwarzschild solution with pseudomatter, pseudomatter halo, collapse involving pseudomatter, pseudomatter in the FLRW universe.
In this brief note we describe two devices, a sort of flat and spherical capacitor, with which one should be able to test the possibility of creating a macroscopic voltage, and thus exploitable current, out of a single thermal source at room temperature. The basic idea is trivial and it makes use of a thermo-emitting cathode with work function as low as 0.7eV. The idea is not completely new, but our approach is simpler and neat. When implemented, it should allow to assess if approaches based on thermo-ionic materials at room temperature really violate the Second Law of Thermodynamics macroscopically.
Assuming the features commonly ascribed to dark matter, we discuss our glimpse of the possibility that dark matter as a light transmitting medium played a role that accounts for the discordant inferences about the dynamical behaviour of light, in which some optical experiments cannot detect the earth's motion in space, while others definitely can. In a converse way, the mentioned laboratory and astronomical observations provide an accessible experimental proof for the existence of a transparent, non-baryonic earth-bound medium which does not occupy the whole of universal space, dark matter being a possible candidate medium.
We make remarks on Ristroph and Zhang's [{\it Phys. Rev. Lett.} 101, 194502 (2008)] paper.
First, it is demonstrated that the Froolich Hamiltonian of system in the superconductivity, proposed by the model of a phonon gas and an electron gas mixture, contains a subtle error. In this respect, we present a correct form of the Froolich Hamiltonian of system where the term of the interaction between the phonon modes and the density modes of the electron modes is described by the term of scattering, introduced by the Froolich in a phonon gas electron gas mixture. The later is removed by a canonical transformation of the Froolich Hamiltonian by an appearance of the attractive interaction mediated via the electron modes, which leads to a bound state on a spinless electron pairs. In this letter, we show that the Cooper approximation as the constancy of the density states within around of the Fermi level has a flaw because the effective attractive forces cannot create the Cooper pairs into energetic gap at the Fermi level. In this letter, we find a condition for density metal which determines metal as superconductor.
Recently, [10,11], the Heisenberg Uncertainty relation and the No-Cloning property in Quantum Mechanics and Quantum Computation, respectively, have been extended to versions of Quantum Mechanics and Quantum Computation which are re-formulated using scalars in {\it reduced power algebras}, [2-9], instead of the usual real or complex scalars. Here, the Lorentz coordinate transformations, fundamental in Special Relativity, are extended to versions of Special Relativity that are similarly re-formulated in terms of scalars in reduced power algebras, instead of the usual real or complex scalars. The interest in such re-formulations of basic theories of Physics are due to a number of important reasons, [2-11]. Suffice to mention two of them : the difficult problem of so called "infinities in Physics" falls easily aside due to the presence of infinitesimal and infinitely large scalars in such reduced power algebras, and the issue of fundamental constants in physics, like Planck's $h$, or the velocity of light $c$, comes under a new focus which offers rather surprising alternatives.
Motivated mainly by the fact that no charged elementary particles having zero mass have been observed up to now, we investigate the question whether the mass of the elementary particles is connected with their electric charge and whether gravity can be derived from QED. The graviton is considered as a two-photon bound state. A relation between mass and charge of elementary particles is derived. Masses of the light quarks $d$ and $u$ are calculated from the electron mass, assuming that $d$, $u$ and $e$ are all fundamental and not composite. In this picture, the heavier quarks and leptons are considered as not fundamental, the massive neutral gauge bosons (and then their charged partners) are composite. The here calculated $u$ and $d$ quark masses, result in quark-mass ratios which display interesting regularities. The lightest quark mass turns out to be quite small. This may be interesting in connection to the strong CP problem.