arXiv subjects

Aleksandr I. Belokon

Publications and source records attributed to Aleksandr I. Belokon.

4 recordsLinked to original sources

arXiv2024

Finite entangling regions and information paradox in charged black holes

In this paper, we study the influence of the electric charge of Reissner-Nordstrom black hole on the dynamics of fine-grained entropy of Hawking radiation, collected in finite entangling regions. We demonstrate that for certain sizes of finite regions, it is always possible to choose a value of the charge such that no information paradox formulated for finite entangling regions arises. For the sake of completeness, we explore how entanglement islands influence the described picture. We find that at small values of the electric charge, there is a discontinuity in the entropy due to the disappearance of the island, and with increasing charge the island ceases to ever dominate throughout entire evolution.

hep-th↗

arXiv2024

Local quenches in fracton field theory: Lieb-Robinson bound, non-causal dynamics and fractal excitation patterns

We study the out-of-equilibrium dynamics induced by a local perturbation in fracton field theory. For the ${\mathbb Z}_4$ and ${\mathbb Z}_8$-symmetric free fractonic theories, we compute the time dynamics of several observables such as the two-point Green function, $\langle ϕ^2 \rangle$ condensate, energy density, and the dipole momentum. The time-dependent considerations highlight that the free fractonic theory breaks causality and exhibits instantaneous signal propagation, even if an additional relativistic term is included to enforce a speed limit in the system. We show that it is related to the fact that the Lieb-Robinson bound does not hold in the continuum limit of the fracton field theory, and the effective bounded speed of light does not emerge. For the theory in finite volume, we show that the fracton wave front acquires fractal shape with non-trivial Hausdorff dimension, and argue that this phenomenon cannot be explained by a simple self-interference effect.

hep-th↗

arXiv2023

From locality to irregularity: Introducing local quenches in massive scalar field theory

In this paper, we initiate the study of operator local quenches in non-conformal field theories. We consider the dynamics of excited local states in massive scalar field theory in an arbitrary spacetime dimension and generalize the well-known two-dimensional CFT results. We derive the energy density, $U(1)$-charge density and $ϕ^2(x)$-condensate post-quench dynamics, and identify different regimes of their evolution depending on the values of the field mass and the quench regularization parameter. For local quenches in higher-dimensional free massless scalar theories, we reproduce the structure of the available holographic results. We also investigate the local quenches in massive scalar field theory on a cylinder and show that they cause an erratic and chaotic-like evolution of observables with a complicated localization/delocalization pattern.

hep-th↗

arXiv2023

Higgs-dilaton model revisited: can dilaton act as QCD axion?

The Standard Model Lagrangian has an approximate scale symmetry in the high-energy limit. This observation can be included in the fundamental principle of the ultimate theory of Nature as the requirement of the exact quantum scale invariance. In this setup, all low-energy particle phenomenology can be obtained as a result of the spontaneous breaking of scale symmetry leading to the presence of the extra massless scalar field -- the dilaton. We explore the scenario in which this field is capable of solving the strong CP-problem in QCD in a similar way as in QCD axion models. The dilaton, playing the role of the axion, is coupled to the QCD sector and acquires a mass term due to non-perturbative breaking of scale symmetry. We show that the dilaton can form dark matter after the low-scale inflation. As a proof of concept, we construct a model of Higgs-driven inflation consistently realising the axion-like dilaton dark matter production compatible with the CMB data.

hep-ph↗