arXiv subjects

Zurab Silagadze

Publications and source records attributed to Zurab Silagadze.

6 recordsLinked to original sources

arXiv2022

Relativity 4-ever?

This essay is about superluminal motion. It is generally believed that special relativity prohibits movements faster than the speed of light. It is explained which motion is actually forbidden by special relativity and why. Tachyons are briefly discussed and it is explained that, due to internal instability, tachyon fields cannot be used to transmit information faster than the speed of light. However, as John Stuart Bell remarked, "what is proved by the impossibility proofs is lack of imagination". Inspired by the Frenkel-Kontorova model of crystal dislocations, we demonstrate the way to overcome the light speed barrier by introducing elvisebrions. Elvisebrions are defined as objects that can exist in the case when some hidden sectors, very weakly interacting with the visible sector, are either not Lorentz invariant, or Lorentz invariant but with different limiting velocities. In this case, elvisebrions can move in a superluminal manner without violating our existing physical models.

physics.pop-ph↗

arXiv2020

Ermakov-Lewis invariant in Koopman-von Neumann mechanics

In the paper Sci. Rep. 8, 8401 (2018), among other things, the Ermakov-Lewis invariant was constructed for the time dependent harmonic oscillator in Koopman-von Neumann mechanics. We point out that there is a simpler method that allows one to find this invariant.

quant-ph↗

arXiv2019

Voigt transformations in retrospect: missed opportunities?

The teaching of modern physics often uses the history of physics as a didactic tool. However, as in this process the history of physics is not something studied but used, there is a danger that the history itself will be distorted in, as Butterfield calls it, a "Whiggish" way, when the present becomes the measure of the past. It is not surprising that reading today a paper written more than a hundred years ago, we can extract much more of it than was actually thought or dreamed by the author himself. We demonstrate this Whiggish approach on the example of Woldemar Voigt's 1887 paper. From the modern perspective, it may appear that this paper opens a way to both the special relativity and to its anisotropic Finslerian generalization which came into the focus only recently, in relation with the Cohen and Glashow's very special relativity proposal. With a little imagination, one can connect Voigt's paper to the notorious Einstein-Poincare priority dispute, which we believe is a Whiggish late time artifact. We use the related historical circumstances to give a broader view on special relativity, than it is usually anticipated.

physics.hist-ph↗

arXiv2017

Radial acceleration relation and dissipative dark matter

Observations indicate that ordinary matter, the baryons, influence the structural properties of dark matter on galactic scales. One such indication is the radial acceleration relation, which is a tight correlation between the measured gravitational acceleration and that expected from the baryons. We show here that the dark matter density profile that has been motivated by dissipative dark matter models, including mirror dark matter, can reproduce this radial acceleration relation.

astro-ph.GA↗

arXiv2016

Dark matter as a cancer hazard

We comment on the paper "Dark Matter collisions with the Human Body" by K. Freese and C. Savage (Phys. Lett. B 717, 25 (2012) [arXiv:1204.1339]) and describe a dark matter model for which the results of the previous paper do not quite apply. Within this mirror dark matter model, potentially hazardous objects, mirror micrometeorites, can exist and may lead to diseases triggered by multiple mutations, such as cancer, though with very low probability.

astro-ph.CO↗

arXiv2008

Quantum-gravitational corrections to the hydrogen atom and harmonic oscillator

It is shown that the rate of corrections to the hydrogen atom and harmonic oscillator due to profound quantum-gravitational effect of space-time dimension running/reduction coincides well with those obtained by means of the minimum-length deformed quantum mechanics. The rate of corrections are pretty much the same within the accuracy by which we can judge the quantum-gravitational corrections at all. Such a convergence of results makes the concept of space-time dimension running more appreciable. As a remarkable distinction, the energy shift due to dimension reduction has the opposite sign as compared with the correction obtained by means of the minimum-length modified quantum mechanics. Thereby, the sign of total quantum-gravitational correction remains obscure.

hep-th↗