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We consider the problem of single link failure in an elastic optical network, (also known as flex-grid WDM network). The task is to reroute optical connections that go through the broken link using free capacity of other links of the network. Nowadays, dynamic restoration gains popularity, in which the possiblity of rerouting is only inspected after a link failure is detected. Since the problem of recovery is NP-hard, heuristic algorithms are used to either find such routes, or suggest that the routes do not exist. In order to understand the quality of these heuristics, often mixed integer linear programming is used to obtain exact positive and negative answers. We present a detailed such model that checks whether restoration is possible without the use of additional regenerators. This means, that the new light paths need to satisfy a length constraint. As preprossing we apply a trimming procedure that takes advantage of this length constraint, and significantly speeds up the evaluation of these models. Our model is more general, and besides solving the problem of link restoration, also solves the full problem of wavelength and spectrum assignment., Comment: Accepted for IEEE BlackSeaCom conference, 7 pages

The RED-100 experiment with a liquid xenon target was carried out at Kalinin Nuclear Power Plant. The goal of the experiment is the detection and study of the coherent elastic neutrino nucleus scattering process (CE$\nu$NS) for the low-energy antineutrinos in close vicinity to a reactor core. A good understanding of the external radioactive background is needed to achieve this goal. This paper describes the external background conditions for the RED-100 experiment at Kalinin Nuclear Power Plant., Comment: 16 pages, 12 figures, (minor changes in the text for clarity)

Let $G$ be a bipartite graph with bipartition $(X,Y)$. Inspired by a hypergraph problem, we seek an upper bound on the number of disjoint paths needed to cover all the vertices of $X$. We conjecture that a Hall-type sufficient condition holds based on the maximum value of $|S|-|\mathsf\Lambda(S)|$, where $S\subseteq X$ and $\mathsf\Lambda(S)$ is the set of all vertices in $Y$ with at least two neighbors in $S$. This condition is also a necessary one for a hereditary version of the problem, where we delete vertices from $X$ and try to cover the remaining vertices by disjoint paths. The conjecture holds when $G$ is a forest, has maximum degree $3$, or is regular with high girth, and we prove those results in this paper.

For quantum electronics, the possibility to finely tune the properties of magnetic topological insulators (TIs) is a key issue. We studied solid solutions between two isostructural Z$_2$ TIs, magnetic MnBi$_2$Te$_4$ and nonmagnetic GeBi$_2$Te$_4$, with Z$_2$ invariants of 1;000 and 1;001, respectively. For high-quality, large mixed crystals of Ge$_x$Mn$_{1-x}$Bi$_2$Te$_4$, we observed linear x-dependent magnetic properties, composition-independent pairwise exchange interactions along with an easy magnetization axis. The bulk band gap gradually decreases to zero for $x$ from 0 to 0.4, before reopening for $x>0.6$, evidencing topological phase transitions (TPTs) between topologically nontrivial phases and the semimetal state. The TPTs are driven purely by the variation of orbital contributions. By tracing the x-dependent $6p$ contribution to the states near the fundamental gap, the effective spin-orbit coupling variation is extracted. As $x$ varies, the maximum of this contribution switches from the valence to the conduction band, thereby driving two TPTs. The gapless state observed at $x=0.42$ closely resembles a Dirac semimetal above the Neel temperature and shows a magnetic gap below, which is clearly visible in raw photoemission data. The observed behavior of the Ge$_x$Mn$_{1-x}$Bi$_2$Te$_4$ system thereby demonstrates an ability to precisely control topological and magnetic properties of TIs.

We apply an unconstrained formulation of bosonic higher spin fields to study interactions of these fields with a bosonic field using new method for the deformation procedure. It is proved that local vertices of any order containing one higher spin $s$ field and arbitrary number of scalar fields and being invariant under original gauge transformations are described with the help of one local totally symmetric $(s-2)$-rank tensor of scalar fields. This tensor is explicitly constructed for particular cases related to cubic vertices for spin $s$ and vertices of an arbitrary order for spin $s=4$., Comment: 12 pages, v2: refs added

New method (arXiv:2104.11930) is applied to construct cubic interactions of massless spin 4 and real scalar fields. In contrast with the case of massless spin 3 fields (arXiv:2208.05700, 2209.03678, 2210.02842) the procedure requires to use an unconstrained formulation (arXiv:0702.161) for the Fronsdal theory. It is shown that in the unconstrained formulation there exists a four-parameter family of cubic interactions between massless spin 4 and real scalar fields, which contains four derivatives in vertices and is invariant with respect to the original gauge transformation. These vertices contain cubic interactions between auxiliary and scalar fields too. Eliminating all auxiliary fields from the obtained result using the equations of motion for the initial action gives a one-parameter family of cubic vertices for constrained massless spin 4 and real scalar fields, Such cubic vertices are invariant with respect to constrained gauge transformations of the Fronsdal theory., Comment: 8 pages. arXiv admin note: text overlap with arXiv:2208.05700, v2: typos corrected

We study the electronic structure of the ferromagnetic spinel $\mathrm{Hg}\mathrm{Cr}_2\mathrm{Se}_4$ by soft-x-ray angle-resolved photoemission spectroscopy (SX-ARPES) and first-principles calculations. While a theoretical study has predicted that this material is a magnetic Weyl semimetal, SX-ARPES measurements give direct evidence for a semiconducting state in the ferromagnetic phase. Band calculations based on the density functional theory with hybrid functionals reproduce the experimentally determined band gap value, and the calculated band dispersion matches well with ARPES experiments. We conclude that the theoretical prediction of a Weyl semimetal state in $\mathrm{Hg}\mathrm{Cr}_2\mathrm{Se}_4$ underestimates the band gap, and this material is a ferromagnetic semiconductor., Comment: 6+13 pages, 4+13 figures

The current understanding of renormalization in quantum gravity (QG) is based on the fact that UV divergences of effective actions in the covariant QG models are covariant local expressions. This fundamental statement plays a central role in QG and, therefore, it is important to prove it for the widest possible range of the QG theories. Using the Batalin-Vilkovisky technique and the background field method, we elaborate the proof of gauge invariant renormalizability for a generic model of quantum gravity that is diffeomorphism invariant and does not have additional, potentially anomalous, symmetries., Comment: References added. 39 pages, no figures. Invited chapter for the Section "Effective Quantum Gravity" of the "Handbook of Quantum Gravity" (Eds. C. Bambi, L. Modesto and I.L. Shapiro, Springer Singapore, expected in 2023). Review paper is mainly based on arXiv:1902.04687, with permission from Physical Review D

An ordered graph is a graph with a linear ordering on its vertices. The online Ramsey game for ordered graphs $G$ and $H$ is played on an infinite sequence of vertices; on each turn, Builder draws an edge between two vertices, and Painter colors it red or blue. Builder tries to create a red $G$ or a blue $H$ as quickly as possible, while Painter wants the opposite. The online ordered Ramsey number $r_o(G,H)$ is the number of turns the game lasts with optimal play. In this paper, we consider the behavior of $r_o(G,P_n)$ for fixed $G$, where $P_n$ is the monotone ordered path. We prove an $O(n \log_2n)$ bound on $r_o(G,P_n)$ for all $G$ and an $O(n)$ bound when $G$ is $3$-ichromatic; we partially classify graphs $G$ with $r_o(G,P_n) = n + O(1)$. Many of these results extend to $r_o(G,C_n)$, where $C_n$ is an ordered cycle obtained from $P_n$ by adding one edge.

As a result of special deformations of free gauge models of massless spin 3, massive vector and real scalar fields, quintic vertices within new approach (Buchbinder and Lavrov in JHEP 06: 097, 2021; Buchbinder and Lavrov in Eur. Phys. J. C 81:856, 2021; Lavrov in Eur. Phys. J. C 82:429, 2022) are constructed. They are described by local functionals which are invariant under original gauge transformations., Comment: 7 pages, v2: typos corrected; accepted in Phys. Lett. B, v3: published version

New local gauge-invariant models of interacting fields with spins 3, 1 and 0 are found. The construction of the models is completely based on the new approach to the deformation problem proposed in our papers (Buchbinder and Lavrov in JHEP 06: 097, 2021; Buchbinder and Lavrov in Eur. Phys. J. C 81:856, 2021; Lavrov in Eur. Phys. J. C 82:429, 2022). The approach allows to describe the deformation procedure for theories with gauge freedom in an explicit and closed form in terms of special anticanonical transformations of the Batalin-Vilkovisky formalism. The action of the models appears as a local part of the deformed action which is represented by a functional of the fourth order in fields. This functional is invariant under original gauge transformations., Comment: 8 pages. arXiv admin note: text overlap with arXiv:2208.05700, v2: typos corrected, ref added

Analysis of genetic data opens up many opportunities for medical and scientific advances. The use of phenotypic information and polygenic risk scores to analyze genetic data is widespread. Most work on genetic privacy focuses on basic genetic data such as SNP values and specific genotypes. In this paper, we introduce a novel methodology to quantify and prevent privacy risks by focusing on polygenic scores and phenotypic information. Our methodology is based on the tool-supported privacy risk analysis method Privug. We demonstrate the use of Privug to assess privacy risks posed by disclosing a polygenic trait score for bitter taste receptors, encoded by TAS2R38 and TAS2R16, to a person's privacy in regards to their ethnicity. We provide an extensive privacy risks analysis of different programs for genetic data disclosure: taster phenotype, tasting polygenic score, and a polygenic score distorted with noise. Finally, we discuss the privacy/utility trade-offs of the polygenic score.

Using new approach for the deformation procedure in the case of reducible gauge theories (Lavrov in Eur. Phys. J. C 82:429, 2022), it is shown that in the model of massless spin 3 field and a real scalar field local cubic and quartic vertices invariant under original gauge transformations can be explicitly constructed., Comment: 11 pages, v2: ref added, minor corrections, v3: typos corrected, section Discussion extended, published version, v4:in Section 4 and Discussion correction of conclusions about cubic vertices made