arXiv subjects

Dragan Slavkov Hajdukovic

Publications and source records attributed to Dragan Slavkov Hajdukovic.

At least 19 recordsLinked to original sources

arXiv2019

Concerning impact of the quantum vacuum on orbits of planets

We point out serious shortcomings of a very recent article (Iorio in Astrophys. Space Sci. 364:126, 2019) wrongly claiming that the current precision with which we know orbits of planets in the Solar System rules out the possibility of gravitational polarization of the quantum vacuum. The main mistake is that the Sun and a planet are considered as an isolated binary system completely neglecting the existence of other planets and their crucial contribution to the gravitational polarization of the quantum vacuum.

physics.gen-ph↗

arXiv2014

Virtual gravitational dipoles: The key for the understanding of the Universe?

Before the end of this decade, three competing experiments (ALPHA, AEGIS and GBAR) will discover if atoms of antihydrogen fall up or down. We wonder what the major changes in astrophysics and cosmology would be if it is experimentally confirmed that antimatter falls upwards. The key point is: If antiparticles have negative gravitational charge, the quantum vacuum, well established in the Standard Model of Particles and Fields, contains virtual gravitational dipoles. The main conclusions are: (1) the physical vacuum enriched with gravitational dipoles is compatible with a cyclic universe alternatively dominated by matter and antimatter, without initial singularity and without need for cosmic inflation; (2) the virtual dipoles might explain the phenomena usually attributed to dark matter and dark energy. While what we have presented is still far from a complete theory, hopefully it can stimulate a radically different and potentially important way of thinking.

physics.gen-ph↗

arXiv2013

A new model of dark matter distribution in galaxies

In the absence of the physical understanding of the phenomenon, different empirical laws have been used as approximation for distribution of dark matter in galaxies and clusters of galaxies. We suggest a new profile which is not empirical in nature, but motivated with the physical idea that what we call dark matter is essentially the gravitational polarization of the quantum vacuum (containing virtual gravitational dipoles) by the immersed baryonic matter. It is very important to include this new profile in forthcoming studies of dark matter halos and to reveal how well it performs in comparison with empirical profiles. A good agreement of the profile with observational findings would be the first sign of unexpected gravitational properties of the quantum vacuum.

physics.gen-ph↗

arXiv2013

The signatures of new physics, astrophysics and cosmology?

The first three years of the LHC experiments at CERN have ended with "the nightmare scenario": all tests, confirm the Standard Model of Particles so well that theorists must search for new physics without any experimental guidance. The supersymmetric theories, a privileged candidate for new physics are nearly excluded. As a potential escape from the crisis, we propose thinking about a series of astonishing relations suggesting fundamental interconnections between the quantum world and the large scale Universe. It seems reasonable that, for instance, the equation relating a quark-antiquark pair with the fundamental physical constants and cosmological parameters must be a sign of new physics. One of the intriguing possibilities is interpreting our relations as a signature of the quantum vacuum containing the virtual gravitational dipoles.

physics.gen-ph↗

arXiv2012

Trans-Neptunian objects: a laboratory for testing the existence of non-Newtonian component of the gravitational force

It is not known if, in addition to the Newton's inverse square law component, the gravitational force has some non-Newtonian, long-range components that have escaped detection until now. For example, the non-Newtonian component of the gravitational force naturally arises if gravity is interpreted as an entropic force, or under far reaching hypothesis that quantum vacuum contains virtual gravitational dipoles. We point out that some trans-Neptunian objects (for instance a binary system or a dwarf planet with its satellite) might be a good laboratory to establish the eventual existence of non-Newtonian components of gravity. The key points are that, in the case of an ideal two-body system, the perihelion precession can be caused only by a gravitational force that deviates from the inverse square law and that the perihelion precession rate is larger in systems with smaller mass. It is shown, that in some trans-Neptunian (two-body) systems, the perihelion precession rate caused by internal interactions might be larger than the (inevitable) precession induced by external gravitational field.

physics.gen-ph↗

arXiv2012

Can observations inside the Solar System reveal the gravitational properties of the quantum vacuum?

The understanding of the gravitational properties of the quantum vacuum might be the next scientific revolution.It was recently proposed that the quantum vacuum contains the virtual gravitational dipoles; we argue that this hypothesis might be tested within the Solar System. The key point is that quantum vacuum ("enriched" with the gravitational dipoles) induces a retrograde precession of the perihelion. It is obvious that this phenomenon might eventually be revealed by more accurate studies of orbits of planets and orbits of the artificial Earth satellites. However, we suggest that potentialy the best "laboratory" for the study of the gravitational properties of the quantum vacuum is the Dwarf Planet Eris and its satellite Dysnomia; the distance of nearly 100AU makes it the unique system in which the precession of the perihelion of Dysnomia (around Eris) is strongly dominated by the quantum vacuum.

physics.gen-ph↗

arXiv2012

Quantum Vacuum and Virtual Gravitational Dipoles: The solution to the Dark Energy Problem?

The cosmological constant problem is the principal obstacle in the attempt to interpret dark energy as the quantum vacuum energy. We suggest that the obstacle can be removed, i.e. that the cosmological constant problem can be resolved by assuming that the virtual particles and antiparticles in the quantum vacuum have the gravitational charge of the opposite sign. The corresponding estimates of the cosmological constant, dark energy density and the equation of state for dark energy are in the intriguing agreement with the observed values in the present day Universe. However, our approach and the Standard Cosmology lead to very different predictions for the future of the Universe; the exponential growth of the scale factor, predicted by the Standard Cosmology, is suppressed in our model.

physics.gen-ph↗

arXiv2011

Quantum vacuum and dark matter

Recently, the gravitational polarization of the quantum vacuum was proposed as alternative to the dark matter paradigm. In the present paper we consider four benchmark measurements: the universality of the central surface density of galaxy dark matter haloes, the cored dark matter haloes in dwarf spheroidal galaxies, the non-existence of dark disks in spiral galaxies and distribution of dark matter after collision of clusters of galaxies (the Bullet cluster is a famous example). Only some of these phenomena (but not all of them) can (in principle) be explained by the dark matter and the theories of modified gravity. However, we argue that the framework of the gravitational polarization of the quantum vacuum allows the understanding of the totality of these phenomena.

physics.gen-ph↗

arXiv2011

Is dark matter an illusion created by the gravitational polarization of the quantum vacuum?

Assuming that a particle and its antiparticle have the gravitational charge of the opposite sign, the physical vacuum may be considered as a fluid of virtual gravitational dipoles. Following this hypothesis, we present the first indications that dark matter may not exist and that the phenomena for which it was invoked might be explained by the gravitational polarization of the quantum vacuum by the known baryonic matter.

physics.gen-ph↗

arXiv2011

On the absolute value of the neutrino mass

The neutrino oscillations probabilities depend on mass squared differences; in the case of 3-neutrino mixing, there are two independent differences, which have been measured experimentally. In order to calculate the absolute masses of neutrinos, we have conjectured a third relation, in the form of a sum of squared masses. The calculated masses look plausible and are in good agreement with the upper bounds coming from astrophysics.

physics.gen-ph↗

arXiv2011

Black Holes and Gravitational Properties of Antimatter

The gravitational properties of antimatter are still a secret of nature. One outstanding possibility is that there is a gravitational repulsion between matter and antimatter (in short we call it antigravity). We argue that in the case of antigravity the collapse of a black hole doesn't end with singularity and that deep inside the horizon, the gravitational field may be sufficiently strong to create (from the vacuum) neutrino-antineutrino pairs of all flavours. The created antineutrinos (neutrinos) should be violently ejected outside the horizon of a black hole composed from matter (antimatter). Our rudimentary calculations suggest that both, the supermassive black hole in the centre of our Galaxy and in the centre of the Andromeda Galaxy may produce a flux of antineutrinos measurable with the new generation of one cubic kilometre neutrino telescopes. In addition, we suggest two signatures of antigravity in the case of microscopic black holes which may be eventually produced at CERN: the decay products should exhibit a strong matter-antimatter asymmetry and the Hawking radiation should not be the main mechanism for decay.

gr-qc↗

arXiv2011

Can the new Neutrino Telescopes reveal the Gravitational Properties of Antimatter?

We argue that the hypothesis of the gravitational repulsion between matter and antimatter can be tested at the Ice Cube, a neutrino telescope, recently constructed at the South Pole. If there is such a gravitational repulsion, the gravitational field, deep inside the horizon of a black hole, might create neutrino-antineutrino pairs from the quantum vacuum. While neutrinos must stay confined inside the horizon, the antineutrinos should be violently ejected. Hence, a black hole (made from matter) should behave as a point-like source of antineutrinos. Our simplified calculations suggest, that the antineutrinos emitted by supermassive black holes in the centre of the Milky Way and Andromeda Galaxy, could be detected by the new generation of neutrino telescopes.

gr-qc↗

arXiv2011

Do we live in the universe successively dominated by matter and antimatter?

We wonder if a cyclic universe may be dominated alternatively by matter and antimatter. Such a scenario demands a mechanism for transformation of matter to antimatter (or antimatter to matter) during the final stage of a big crunch. By giving an example, we have shown that in principle such a mechanism is possible. Our mechanism is based on a hypothetical repulsion between matter and antimatter, existing at least deep inside the horizon of a black hole. When universe is reduced to a supermassive black hole of a small size, a very strong field of the conjectured force might create (through a Schwinger type mechanism) particle-antiparticle pairs from the quantum vacuum. The amount of antimatter created from the vacuum is equal to the decrease of mass of the black hole and violently repelled from it. When the size of the black hole is sufficiently small, the creation of antimatter may become so fast, that matter of our Universe might be transformed to antimatter in a fraction of second. Such a fast conversion of matter into antimatter may look as a Big Bang. Our mechanism prevents a singularity; a new cycle might start with an initial size more than 30 orders of magnitude greater than the Planck length, suggesting that there is no need for inflationary scenario in Cosmology. In addition, there is no need to invoke CP violation for explanation of matter-antimatter asymmetry. Simply, our present day Universe is dominated by matter, because the previous universe was dominated by antimatter.

physics.gen-ph↗

arXiv2011

Vacuum fluctuations, the size of extra spatial dimensions and microscopic black holes at CERN

We have suggested, that the size of extra spatial dimensions (if they exist) should be related to the quantum vacuum fluctuations; an extra dimension must be sufficiently large to allow appearance of virtual quark-antiquark pairs, which are an inherent part of the physical vacuum in quantum chromodynamics. We argue that the conjecture of extra dimensions with the universal size equal to the reduced Compton wavelength of a pion is a serious alternative to the postulated universal mass in the theory of large extra dimensions (LED). Our conjecture leads to the conclusion that the production of artificial mini black holes at LHC at CERN is unlikely. It is shown that the recent lower limit on the mass of a microscopic black hole (established by CMS collaboration at CERN) may be interpreted as the upper limit (equal to six) for the number of extra dimensions. Additionally, we challenge the current wisdom that mini black holes disintegrate through the Hawking radiation. We point that it might be wrong, if there is a hypothetical repulsion between matter and antimatter; resulting in the creation of particle-antiparticle pairs from the quantum vacuum and matter-antimatter asymmetry in the spectrum of radiation.

gr-qc↗

arXiv2011

A few provoking relations between dark energy, dark matter and pions

I present three relations, striking in their simplicity and fundamental appearance. The first one connects the Compton wavelength of a pion and the dark energy density of the Universe; the second one connects Compton wavelength of a pion and the mass distribution of non-baryonic dark matter in a Galaxy; the third one relates mass of a pion to fundamental physical constants and cosmological parameters. All these relations are in excellent numerical agreement with observations.

physics.gen-ph↗

arXiv2011

On the vacuum fluctuations, Pioneer Anomaly and Modified Newtonian Dynamics

We argue that the so-called "Pioneer Anomaly" is related to the quantum vacuum fluctuations. Our approach is based on the hypothesis of the gravitational repulsion between matter and antimatter, what allows considering, the virtual particle-antiparticle pairs in the physical vacuum, as gravitational dipoles. Our simplified calculations indicate that the anomalous deceleration of the Pioneer spacecrafts could be a consequence of the vacuum polarization in the gravitational field of the Sun. At the large distances, the vacuum polarization by baryonic matter could mimic dark matter what opens possibility that dark matter do not exist, as advocated by the Modified Newtonian Dynamics (MOND).

physics.gen-ph↗

arXiv2011

What would be outcome of a Big Crunch?

I suggest the existence of a still undiscovered interaction: repulsion between matter and antimatter. The simplest and the most elegant candidate for such a force is gravitational repulsion between particles and antiparticles. I argue that such a force may give birth to a new Universe; by transforming an eventual Big Crunch of our universe, to an event similar to Big Bang. In fact, when a collapsing Universe is reduced to a supermassive black hole of a small size, a very strong field of the conjectured force may create particle-antiparticle pairs from the surrounding vacuum. The amount of the antimatter created from the physical vacuum is equal to the decrease of mass of "black hole Universe" and violently repelled from it. When the size of the black hole is sufficiently small the creation of antimatter may become so huge and fast, that matter of our Universe may disappear in a fraction of the Planck time. So fast transformation of matter to antimatter may look like a Big Bang with the initial size about 30 orders of magnitude greater than the Planck length, questioning the need for inflation. In addition, a Big Crunch, of a Universe dominated by matter, leads to a new Universe dominated by antimatter, and vice versa; without need to invoke CP violation as explanation of matter-antimatter asymmetry. Simply, our present day Universe is dominated by matter, because the previous Universe was dominated by antimatter.

physics.gen-ph↗

arXiv2011

On the relation between mass of pion, fundamental physical constants and cosmological parameters

In this article we reconsider the old mysterious relation, advocated by Dirac and Weinberg, between the mass of the pion, the fundamental physical constants, and the Hubble parameter. By introducing the cosmological density parameters, we show how the corresponding equation may be written in a form that is invariant with respect to the expansion of the Universe and without invoking a varying gravitational "constant", as was originaly proposed by Dirac. It is suggest that, through this relation, Nature gives a hint that virtual pions dominante the "content" of the quantum vacuum.

physics.gen-ph↗