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I. B. Khriplovich

Publications and source records attributed to I. B. Khriplovich.

At least 19 recordsLinked to original sources
arXiv2024

Gravitational four-fermion interaction and dynamics of the early Universe

If torsion exists, it generates gravitational four-fermion interaction (GFFI), essential on the Planck scale. We analyze the influence of this interaction on the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology. Explicit analytical solution is derived for the problem where both the energy-momentum tensor generated by GFFI and the common ultrarelativistic energy-momentum tensor are included. We demonstrate that gravitational four-fermion interaction does not result in Big Bounce.

astro-ph.CO↗
arXiv2024

Cosmology constrains gravitational four-fermion interaction

If torsion exists, it generates gravitational four-fermion interaction (GFFI). This interaction gets dominating on the Planck scale. If one confines to the regular, axial-axial part of this interaction, the results do not comply with the Friedmann-Lemaitre-Robertson-Walker (FLRW) cosmology for the spatial flat or closed Universe. In principle, the anomalous, vector-vector interaction could restore the agreement.

astro-ph.CO↗
arXiv2017

Positron production in collision of heavy nuclei

We consider the electromagnetic production of positron in collision of slow heavy nuclei, with the simultaneously produced electron captured by one of the nuclei. The cross-section of the discussed process exceeds essentially the cross-section of $e^+e^-$ production.

nucl-th↗
arXiv2016

Positron production in collision of heavy nuclei

We consider the electromagnetic production of positron in collision of heavy nuclei, with the simultaneously produced electron captured by one of the nuclei. This cross-section exceeds by about four orders of magnitude the cross-section of $e^+ e^-$ production.

nucl-th↗
arXiv2012

Big bounce and inflation from gravitational four-fermion interaction

The four-fermion gravitational interaction is induced by torsion, and gets dominating on the Planck scale. The regular, axial-axial part of this interaction by itself does not stop the gravitational compression. However, the anomalous, vector-vector interaction results in a natural way both in big bounce and in inflation.

gr-qc↗
arXiv2012

Gravitational four-fermion interaction on the Planck scale

The four-fermion gravitational interaction is induced by torsion, and gets essential on the Planck scale. On this scale, the axial-axial contribution dominates strongly in the discussed interaction. The energy-momentum tensor, generated by this contribution, is analyzed, as well as stability of the problem with respect to compression. The trace of this energy-momentum tensor can be negative.

gr-qc↗
arXiv2010

$K^+_{l3γ}$ decays revisited: branching ratios and T-odd momenta correlations

We calculate the branching ratios of the $K^+ \to π^0 l^+ ν_lγ(l = e, μ)$ decays, and the T-odd triple momenta correlations $ξ=\vec{q}\cdot[\vec{p}_l \times \vec{p}_π]/M^3_K$, due to the electromagnetic final state interaction, in these processes. The contributions on the order of $ω^{-1}$ and $ω^0$ to the corresponding amplitudes are treated exactly. For the branching ratios, the corrections on the order of $ω$ are estimated and demonstrated to be small. We compare the results with those of other authors. In some cases our results differ considerably from the previous ones.

hep-ph↗
arXiv2010

Comment on "Comments on recent work on dark-matter capture in the Solar System"

The criticism contained in the recent preprint arxiv:1004.5258 is based essentially on misquoting the articles criticized therein. As to the conclusion advocated in that preprint, according to which the density of dark matter bound to the Solar System is small as compared to the dark-matter density in the Galactic halo, it is not clear whether this claim is correct.

astro-ph.EP↗
arXiv2010

Capture of dark matter by the Solar System. Simple estimates

We consider the capture of galactic dark matter by the Solar System, due to the gravitational three-body interaction of the Sun, a planet, and a dark matter particle. Simple estimates are presented for the capture cross-section, as well as for density and velocity distribution of captured dark matter particles close to the Earth.

astro-ph.EP↗
arXiv2009

Comment on "Rovibrational quantum interferometers and gravitational waves"

In a recent paper, Wicht, Lämmerzahl, Lorek, and Dittus [Phys. Rev. {\bf A 78}, 013610 (2008)] come to the conclusion that a molecular rotational-vibrational quantum interferometer may possess the sensitivity necessary to detect gravitational waves. We do not agree with their results and demonstrate here that the true sensitivity of such interferometer is many orders of magnitude worse than that claimed in the mentioned paper. In the present comment we estimate the expected energy shifts and derive equations of motion for a quantum symmetric top (diatomic molecule or deformed nucleus) in the field of gravitational wave, and then estimate the sensitivity of possible experiments.

physics.atom-ph↗
arXiv2009

Capture of dark matter by the Solar System

We study the capture of galactic dark matter by the Solar System. The effect is due to the gravitational three-body interaction between the Sun, one of the planets, and a dark matter particle. The analytical estimate for the capture cross-section is derived and the upper and lower bounds for the total mass of the captured dark matter particles are found. The estimates for their density are less reliable. The most optimistic of them give an enhancement of dark matter density by about three orders of magnitudes compared to its value in our Galaxy. However, even this optimistic value remains below the best present observational upper limits by about two orders of magnitude.

astro-ph.SR↗