Topic overview

physics.gen-ph

588 works821 researchers

Open map Browse papers

Map preview

Start with the graph, then narrow the list

588works

821researchers

Next steps

Use the topic as a working map

Open the full map for clusters, then return here to scan ranked papers and people.

Inspect nearby papers, researchers, institutions and communities without opening a separate graph page.

Building this map preview

BZPEER is loading the nearby papers, people, topics and institutions for this page.

preprint2016arXiv

A Local and Discrete Model Simulating Nonrelativistic Quantum Mechanical Systems

This paper presents a simple model that mimics quantum mechanics (QM) results without using complex wavefunctions or non-localities. The proposed model only uses integer-valued quantities and arithmetic operations, in particular assuming a discrete spacetime under the form of a Euclidean lattice. The proposed approach describes individual particle trajectories as random walks. Transition probabilities are simple functions of a few quantities that are either randomly associated to the particles during their preparation, or stored in the lattice nodes they visit during the walk. Non-relativistic QM predictions are retrieved as probability distributions of similarly-prepared ensembles of particles. The scenarios considered to assess the model comprise of free particle, constant external force, harmonic oscillator, particle in a box, and the Delta potential.

preprint2016arXiv

Einstein-Podolsky-Rosen Paradox in Quantum Diagrams

Quantum diagrams are the best language for Quantum Mechanics since they show not only a final result but also the physical process which leads to the result. The quantum correlation at a distance better known as the Einstein-Podolsky-Rosen paradox may be easily understood being depicted in the time-ordered quantum diagrams. In the diagrams one can clearly see what the so-called entangled quantum states really are and how they contribute to the violation of Bell inequality. The wave function phase relations that are the actual physical "common cause in the past" for the observed correlation become also visual and evident. Thus the diagram analysis shows that the phenomenon of distant quantum correlation has simple causal and local explanation and there is no need to invent various extravagant constructions contradicting the established physical principles as well as usual common sense considerations.

preprint2016arXiv

Horizon Quantum Mechanics of Generalized Uncertainty Principle Black Holes

We study the Horizon Wavefunction (HWF) description of a generalized uncertainty principle inspired metric that admits sub-Planckian black holes, where the black hole mass $m$ is replaced by $M = m\left( 1 + \fracβ{2} \frac{M_{\rm Pl}^2}{m^2} \right)$. Considering the case of a wave-packet shaped by a Gaussian distribution, we compute the HWF and the probability ${\cal {P}}_{BH}$ that the source is a (quantum) black hole, i.e., that it lies within its horizon radius. The case $β<0$ is qualitatively similar to the standard Schwarzschild case, and the general shape of ${\cal {P}}_{BH}$ is maintained when decreasing the free parameter, but shifted to reduce the probability for the particle to be a black hole accordingly. The probability grows with increasing mass slowly for more negative $β$, and drops to 0 for a minimum mass value. The scenario differs in significantly for increasing $β>0$, where a minimum in ${\cal {P}}_{BH}$ is encountered, thus meaning that every particle has some probability of decaying to a black hole. Furthermore, for sufficiently large $β$ we find that every particle is a quantum black hole, in agreement with the intuitive effect of increasing $β$, which creat

preprint2016arXiv

Ultra-light and strong: the massless harmonic oscillator and its singular path integral

In classical mechanics, a light particle bound by a strong elastic force just oscillates at high frequency in the region allowed by its initial position and velocity. In quantum mechanics, instead, the ground state of the particle becomes completely de-localized in the limit $m \to 0$. The harmonic oscillator thus ceases to be a useful microscopic physical model in the limit $m \to 0$, but its Feynman path integral has interesting singularities which make it a prototype of other systems exhibiting a "quantum runaway" from the classical configurations near the minimum of the action. The probability density of the coherent runaway modes can be obtained as the solution of a Fokker-Planck equation associated to the condition $S=S_{min}$. This technique can be applied also to other systems, notably to a dimensional reduction of the Einstein-Hilbert action.

preprint2016arXiv

Lorentz Force and Ponderomotive Force in the Presence of a Minimal Length

In this work, according to the electromagnetic field tensor in the framework of generalized uncertainty principle (GUP), we obtain the Lorentz force and Faraday's law of induction in the presence of a minimal length. Also, the ponderomotive force and pomderomotive pressure in the presence of a measurable minimal length are found.

preprint2016arXiv

What is the physical meaning of mass in view of wave-particle duality? A proposed model

Mass is an important concept in classical mechanics, which regards a particle as a corpuscular object. But according to wave-particle duality, we know a free particle can behave like a wave. Is there a wave property that corresponds to the mass of a particle? This is an interesting question that has not been extensively explored before. We suggest that this problem can be approached by treating the mass on the same footing as energy and momentum. Here we propose that, all particles are excitation waves of the vacuum and different particles are represented by different excitation modes. Based on such a model, we found that mass is not an intrinsic property of the particle. Instead, mass is basically a measure of the particle energy. The relations between energy and mass can be directly derived based on the wave properties of the particle. This work explains why some particles are "wave-like" while others are "particle-like". Furthermore, this work has several interesting implications. It directly explains why photons can interact with a gravitational field. It also suggests a possible origin of dark matter; they are thought to be composed of excitation waves that fai

preprint2016arXiv

Dirac Equation in Four Time and Four Space Dimensions

The Dirac equation in four time and four space dimensions (or (4+4)-dimensions) is considered. Step by step we show that such an equation admits Majorana and Weyl solutions. In order to obtain the Majorana or Weyl spinors we used a method based on the construction of Clifford algebra in terms of 2x2-matrices. We argue that our approach can be useful in supergravity, superstrings and qubit theory.

preprint2016arXiv

Physics in 2116: Physicists Create Closed Time-like Curves

This is an entry for Physics Today's recent essay contest, written as a "Search and Discovery" news story, imagining what major breakthroughs might be shaking the physics world one hundred years from now.

preprint2007arXiv

About Superluminal motions and Special Relativity: A Discussion of some recent Experiments, and the solution of the Causal Paradoxes

Some experiments, performed at Berkeley, Cologne, Florence, Vienna, Orsay, Rennes, etc., led to the claim that something seems to travel with a group velocity larger than the speed c of light in vacuum. Various other experimental results seem to point in the same direction: For instance, localized wavelet- type solutions to Maxwell equations have been found, both theoretically and experimentally, that travel with superluminal speed. [Even muonic and electronic neutrinos [it has been proposed] might be "tachyons", since their square mass appears to be negative]. With regard to the first-mentioned experiments, it was recently claimed by Guenter Nimtz that those results with evanescent waves (or tunneling photons) imply superluminal signal and impulse transmission, and therefore violate Einstein causality. In this note we want to stress that, on the contrary, all such results do not place relativistic causality in jeopardy, even if they referred to actual tachyonic motions: In fact, Special Relativity can cope even with superluminal objects and waves. For instance, it is possible (at least in microphysics) to solve also the known causal paradoxes, devised for faster than light

preprint2006arXiv

Neutrino and/or etherino?

We review the insufficiencies of the hypothesis that neutrinos and quarks are physical particles in our spacetime; we introduce the hypothesis that the energy and spin needed for the synthesis of the neutron inside stars originate either from the environment or from the ether conceived as a universal medium with very high energy density via an entity here called {\it etherino,} denoted with the letter "$a$" (from the Latin aether), carrying mass and charge 0, spin 1/2 and $0.78 MeV$ energy according to the synthesis $p^+ + a + e^-\to n$; we identifies compatibility and incompatibility of the neutrino and etherino hypotheses; we review the new structure model of the neutron and hadrons at large with massive physical constituents produced free in the spontaneous decays as permitted by the covering hadronic mechanics; and we conclude with the proposal of new resolutory experiments.

preprint2016arXiv

Compact star model in Einstein Gauss-Bonnet Gravity within the framework of Finch Skea space time

In this article we provide a new class of interior solutions of a five dimensional compact star in Einstein Gauss-Bonnet (EGB) gravity within the framework of Finch-skea space time. The Exterior space time is described by the EGB schwarzschild solution. To check physically validity of our model we investigate various physical properties like causality of solutions, Energy conditions, mass radius relations, TOV equations etc.

preprint2016arXiv

Connection between Symmetrical Special Relativity and the Gravitational Bose Einstein Condensate of a Gravastar/Dark Energy Star: Are there singularities in spacetime like black holes?

We aim to search for a connection between an invariant minimum speed that breaks down the Lorentz symmetry and the Gravitational Bose Einstein Condensate (GBEC), which is the central core of a star of gravitating vacuum (Gravastar/Dark Energy Star) by introducing a cosmological constant into compact objects. This model was designed to circumvent the embarrassment generated by the paradoxes of a singularity as the final stage of a gravitational collapse, by introducing in place of the singularity of event horizon a spatial-temporal phase transition, a concept with which the causal structure of Symmetrical Special Relativity (SSR) helps us to elucidate by providing a quantum interpretation for GBEC and explaining the origin of anisotropy, which has been introduced in ad-hoc way before in the literature.

preprint2016arXiv

Topologically nontrivial solution in Einstein-Dirac gravity on the Hopf bundle

The topologically nontrivial solution in Einstein-Dirac gravity with cosmological constant is obtained. The spacetime has the Hopf bundle as a spatial section. It is shown that the Hopf invariant is related to the spinor current density. Two Dirac spinors are used for obtaining a diagonal energy-momentum tensor. The solutions for the nongravitating Dirac equation on the background of Lorentzian spacetime with the Hopf bundle as a spatial section are also obtained. Nongravitating solutions of the Dirac equation are defined by two quantum half-integer numbers $m, n$.

preprint2016arXiv

Thermodynamics of flat FLRW universe in Rastall Theory

In this paper, after referring to the Rastall theory, we address some of its cosmological consequences. Moreover, bearing the Clausius relation in mind, using Friedman equations in Rastall theory and the Cai-Kim temperature, we obtain a relation for the apparent horizon entropy of a flat FLRW universe. In addition, we impose the entropy positivity condition on the obtained relation for the horizon entropy, to find some constraints on the Rastall parameters. Moreover, we investigate the second and generalized second laws of thermodynamics. The results of considering a dominated prefect fluid with constant state parameter are also addressed helping us familiarize with the Rastall theory.

preprint2016arXiv

On the definition of the measurement unit for extreme quantity values: some considerations on the case of temperature and the kelvin scale

Many quantities are attributed a range of values that can apparently extend to infinity (on one side or both sides). In this respect, the definitions of their measurement units do not place any constraint to the maximum (or minimum) value for their validity. In general, that happens because those extreme values are far from being reached on the earth, or presently in experiments. However, since the same units are used also in fields of physics, chemistry or technology where they could occur, namely in the description of the universe in one sense, and in nano-scale or particle physics in another sense, the issue of extreme values (not in statistical meaning here) is not irrelevant. The question placed and discussed in this paper is whether the present kelvin scale, based on Lord Kelvin second definition (our currently accepted concept of temperature), applies over a full range between bounds (zero, infinite) or not, and about the concept of temperature in itself in the extremes regions. The aim, however, is not to provide an answer, but to suggest there are difficulties with the application of current concepts at extremes of temperature.

preprint2016arXiv

Continuum dynamics and the electromagnetic field in the scalar ether theory of gravitation

An alternative, scalar theory of gravitation has been proposed, based on a mechanism/interpretation of gravity as being a pressure force: Archimedes' thrust. In it, the gravitational field affects the physical standards of space and time, but motion is governed by an extension of the relativistic form of Newton's second law. This implies Einstein's geodesic motion for free particles only in a constant gravitational field. In this work, equations governing the dynamics of a continuous medium subjected to gravitational and non-gravitational forces are derived. Then, the case where the non-gravitational force is the Lorentz force is investigated. The gravitational modification of Maxwell's equations is obtained under the requirement that a charged continuous medium, subjected to the Lorentz force, obeys the equation derived for continuum dynamics under external forces. These Maxwell equations are shown to be consistent with the dynamics of a "free" photon, and thus with the geometrical optics of this theory. However, these equations do not imply local charge conservation, except for a constant gravitational field. Keywords: Alternative theories of gravitation;

preprint2016arXiv

Dark Matter Particles with Low Mass (and FTL)

From the observed results, we deduced that the mass of the neutrino is about 10^(-1) eV and the mass of the fourth stable elementary particle (delta) is about 10^(0) eV. While neutrino is related to electro-weak field, the fourth stable elementary particle delta is related to gravitation-"strong" field, and some new meta-stable baryons may appear near the TeV region. Therefore, a twofold standard model diagram is proposed, and involves some experiment phenomena: The new meta-stable baryons' decays produce delta particles, which are helpful in explaining the Dijet asymmetry phenomena at LHC of CERN, the different results for the Fermilab's data peak, etc; However, according to the (B-L) invariance, the sterile "neutrino" about the event excess in MiniBooNe is not the fourth neutrino but rather the delta particle; We think that the delta particles are related to the phenomenon about neutrinos FTL, and that anti-neutrinos are faster than neutrinos. FTL is also related to cosmic inflation, singular point disappearance, a finite universe, and abnormal red shift of SN Ia. Besides, the dark matter particles with low mass are helpful in explaining missing solar neut

preprint2016arXiv

Weak measurements and supraluminal communication

There is suggested a version of the experiment with a correlated pair of particles in the entangled state. The experiment demonstrates that, in the case of weak and/or non-demolition measurements of one of the particles, it is possible to transmit information with a speed not limited by velocity of light.

preprint2016arXiv

Fermion regularization, fermion measure and axion fields

Axion fields were originally introduced to control CP violation due to the theta term in QCD. Pauli-Villars regularization, or the use of a parity symmetric fermion measure, however, preserves CP in the fermion sector. A CP violation arising from the theta term can then be neutralized in a natural way by setting theta equal to zero.

preprint2016arXiv

Some Mathematical and Physical Remarks on Surreal Numbers

We make a number of observations on Conway surreal number theory which may be useful, for further developments, in both in mathematics and theoretical physics. In particular, we argue that the concepts of surreal numbers and matroids can be linked. Moreover, we established a relation between the Gonshor approach on surreal numbers and tensors. We also comment about the possibility to connect surreal numbers with supesymmetry. In addition, we comment about possible relation between surreal numbers and fractal theory. Finally, we argue that the surreal structure may provide a different mathematical tools in the understanding of singularities in both high energy physics and gravitation.

preprint2016arXiv

Faddeev-Jackiw analysis for the charged compressible fluid in a higher-derivative electromagnetic field background

In the present paper we will discuss the Faddeev-Jackiw symplectic approach in the analysis of a charged compressible fluid immersed in a higher-derivative electromagnetic field theory. We have obtained the full set of constraints directly from the zero-mode eigenvectors. Besides, we have computed the Dirac brackets for the dynamic variables of the compressible fluid. Finally, as a result of the coupling between the charged compressible fluid and the electromagnetic field we have calculated two Dirac brackets between the fluid and electromagnetic fields, which are both zero when there is no coupling between them.

preprint2007arXiv

Nontrivial quantum effects in biology: A skeptical physicists' view

Invited contribution to "Quantum Aspects of Life", D. Abbott Ed. (World Scientific, Singapore, 2007).

preprint2016arXiv

Emergence of the world with Lie-N-algebra and M-dimensions from nothing

In this paper, we propose a new model in Lie-N-algebra that removes big bang singularity and produces the world with all it's objects and dimensions from nothing. We name this theory as G-theory. In this model, first, two types of energies with opposite signs are produced from nothing such as the sum over them be zero. They create two types of branes with opposite quantum numbers which interact with each other by exchanging bosonic tensor fields like graviton and compact. By compacting branes, fermionic tensor fields are emerged which some of them play the role of the gravitinos. Also, some dimensions take extra (i) factors, their properties become different and they behave like time dimensions. Gravitons and gravitinos create two types of wormholes which lead to the oscillation of branes between expansion and contracting branches. These wormholes produce a repulsive gravity in compacted branes and cause that their particles get away from each other and expansion branch begin. Also, they create an attractive gravity in opening branes and lead to closing their particles and starting the contraction epoch. Our universe is born on one of these branes and oscillates between contrac

preprint2016arXiv

Effect of sliding friction in harmonic oscillators

Sliding friction is ubiquitous in nature as are harmonic oscillators. However, when treating harmonic oscillators the effect of sliding friction is often neglected. Here, we propose a simple analytical model to include both viscous and sliding fiction in common harmonic oscillator equations, allowing to separate these different types of dissipation. To compare this model with experimental data, a nanometric vibration was imposed on a quartz tuning fork, while an atomic force microscope tip was used to disturb its motion. We analyzed tuning fork resonance curves and `ring down' experiments and for each case calculated the amount of sliding friction and of viscous damping, finding an agreement between the two different experiments and the model proposed.

360 works