arXiv subjects

Alexander Baranov

Publications and source records attributed to Alexander Baranov.

15 recordsLinked to original sources

arXiv2025

KoWit-24: A Richly Annotated Dataset of Wordplay in News Headlines

We present KoWit-24, a dataset with fine-grained annotation of wordplay in 2,700 Russian news headlines. KoWit-24 annotations include the presence of wordplay, its type, wordplay anchors, and words/phrases the wordplay refers to. Unlike the majority of existing humor collections of canned jokes, KoWit-24 provides wordplay contexts -- each headline is accompanied by the news lead and summary. The most common type of wordplay in the dataset is the transformation of collocations, idioms, and named entities -- the mechanism that has been underrepresented in previous humor datasets. Our experiments with five LLMs show that there is ample room for improvement in wordplay detection and interpretation tasks. The dataset and evaluation scripts are available at https://github.com/Humor-Research/KoWit-24

cs.CL↗

arXiv2024

Measuring the Evolution of Entanglement in Compton Scattering

The evolution of the entanglement measure during Compton scattering is studied. Our analytical results show that the corresponding measure coincides with the concurrence of the two-qubit state arising after scattering. The state never collapses to a separable one, contrary to what was previously assumed. The behavior of quantum entanglement during scattering is identical to the behavior of initially classically correlated photons up to a constant factor equal to two. This is consistent with local quantum field theory, and "spooky action at a distance" is not required to explain the change in state of nonlocally entangled qubits during the measurement of one of them. Our dedicated experiment with annihilation photons confirms these results and explains the "Puzzle of Decoherence" observed recently.

quant-ph↗

arXiv2022

Entanglement of annihilation photons

We present the results of a new experimental study of the quantum entanglement of photon pairs produced in positron-electron annihilation at rest. The experimental setup includes a system of Compton polarimeters to measure the Compton scattering of annihilation photons in entangled and decoherent states. Decoherent states are prepared by pre-scattering of one of the initial photons prior to measurements in polarimeters. For the first time, a direct comparison of the polarization correlations of annihilation photons in the entangled and thus prepared separable states has been carried out. The angular distributions of scattered photons turned out to be the same in both quantum states, which is an unexpected discovery for the quantum-entangled positron emission tomography. Moreover, the correlation function in the Bell's inequality is also the same for entangled and separable states. It follows that, despite numerous measurements in a series of experiments, there is still no experimental proof of the entanglement of annihilation photons. These results are in line with recent theoretical predictions of an identical Compton scattering cross-section for entangled and specific mixed separable quantum states and cast doubt on the universality of the Bell's theorem for testing the entanglement and nonlocality in quantum theory.

quant-ph↗

arXiv2021

Lie algebras graded by the weight system $(Θ_{n},sl_{n})$

A Lie algebra $L$ is said to be $(Θ_{n},sl_{n})$-graded if it contains a simple subalgebra $\mathfrak{g}$ isomorphic to $sl_{n}$ such that the $\mathfrak{g}$-module $L$ decomposes into copies of the adjoint module, the trivial module, the natural module $V$, its symmetric and exterior squares $S^{2}V$ and $\wedge^{2}V$ and their duals. We describe the multiplicative structures and the coordinate algebras of $(Θ_{n},sl_{n})$-graded Lie algebras for $n\ge5$, classify these Lie algebras and determine their central extensions.

math.RA↗

arXiv2021

Weight zero in tensor-decomposable irreducible representations of simple algebraic groups

Let $G$ be a simple algebraic group in defining characteristic $p>0$, and let $V$ be an irreducible $G$-module which is the tensor product of exactly two non-trivial modules. We obtain a criterion for $V$ to have the zero weight. In addition, we provide a uniform criterion for an irreducible representation of a simple Lie algebra over the complex numbers to have a multiple of a prescribed fundamental weight.

math.RT↗

arXiv2019

Maximal zero product subrings and inner ideals of simple rings

Let Q be a (non-unital) simple ring. A nonempty subset S of Q is said to have zero product if S^2=0. We classify all maximal zero product subsets of Q. We also describe the relationship between the maximal zero product subsets of Q and the maximal inner ideals of its associated Lie algebra.

math.RA↗

arXiv2019

Jordan-Lie inner ideals of finite dimensional associative algebras

We study Jordan-Lie inner ideals of finite dimensional associative algebras and the corresponding Lie algebras and prove that they admit Levi decompositions. Moreover, we classify Jordan-Lie inner ideals satisfying a certain minimality condition and show that they are generated by pairs of idempotents.

math.RA↗

arXiv2018

Lie structure of associative algebras containing matrix subalgebras

We prove that the Lie commutator subalgebra of the associative algebra containing a matrix subalgebra is perfect.

math.RA↗

arXiv2018

Magnetically Tunable Chirality in 2D Liquid Crystalline WS2 Nanocomposites

The first observation of tungsten disulfide liquid crystalline nanocomposites in dispersions of liquid phase-exfoliated flakes is demonstrated in a range of organic solvents. The nanocomposites demonstrate significant birefringence and reconfigurable optical chirality as observed in the linear and circular dichroism measurements respectively. Under an applied magnetic field of +/-1.5T the chirality can be switched ON/OFF, while the wavelength range for switching can be tuned from large to narrow range by the proper selection of the host solvent. In combination with photoluminescence capabilities of WS2, this opens a pathway to a wide variety of applications, such as deposition of highly uniform films over large areas for photovoltaic devices, as shown here.

cond-mat.mtrl-sci↗

arXiv2017

Wedderburn-Malcev decomposition of one-sided ideals of finite dimensional algebras

Let $A$ be a finite dimensional associative algebra over a perfect field and let $R$ be the radical of $A$. We show that for every one-sided ideal $I$ of $A$ there exists a semisimple subalgebra $S$ of $A$ such that $I=I_{S}\oplus I_{R}$ where $I_{S}=I\cap S$. and $I_{R}=I\cap R$.

math.RA↗

arXiv2016

Quantum exceptional group $G_2$ and its conjugacy classes

We construct quantization of semisimple conjugacy classes of the exceptional group $G=G_2$ along with and by means of their exact representations in highest weight modules of the quantum group $U_q(\mathfrak{g})$. With every point $t$ of a fixed maximal torus we associate a highest weight module $M_t$ over $U_q(\mathfrak{g})$ and realize the quantized polynomial algebra of the class of $t$ by linear operators on $M_t$. Quantizations corresponding to points of the same orbit of the Weyl group are isomorphic.

math.QA↗

arXiv2015

Reproducible Experiment Platform

Data analysis in fundamental sciences nowadays is an essential process that pushes frontiers of our knowledge and leads to new discoveries. At the same time we can see that complexity of those analyses increases fast due to a)~enormous volumes of datasets being analyzed, b)~variety of techniques and algorithms one have to check inside a single analysis, c)~distributed nature of research teams that requires special communication media for knowledge and information exchange between individual researchers. There is a lot of resemblance between techniques and problems arising in the areas of industrial information retrieval and particle physics. To address those problems we propose Reproducible Experiment Platform (REP), a software infrastructure to support collaborative ecosystem for computational science. It is a Python based solution for research teams that allows running computational experiments on shared datasets, obtaining repeatable results, and consistent comparisons of the obtained results. We present some key features of REP based on case studies which include trigger optimization and physics analysis studies at the LHCb experiment.

physics.data-an↗

arXiv2013

Modular representations of the special linear groups with small weight multiplicities

We classify irreducible representations of the special linear groups in positive characteristic with small weight multiplicities with respect to the group rank and give estimates for the maximal weight multiplicities. For the natural embeddings of the classical groups, inductive systems of representations with totally bounded weight multiplicities are classified. An analogue of the Steinberg tensor product theorem for arbitrary indecomposable inductive systems for such embeddings is proved.

math.RT↗

arXiv2013

Classification of the direct limits of involution simple associative algebras and the corresponding dimension groups

A classification of (countable) direct limits of finite dimensional involution simple associative algebras over an algebraically closed field of arbitrary characteristic is obtained. This also classifies the corresponding dimension groups. The set of invariants consists of two supernatural numbers and two real parameters.

math.RA↗

arXiv2013

Inner Ideals of Simple Locally Finite Lie Algebras

Inner ideals of simple locally finite dimensional Lie algebras over an algebraically closed field of characteristic 0 are described. In particular, it is shown that a simple locally finite dimensional Lie algebra has a non-zero proper inner ideal if and only if it is of diagonal type. Regular inner ideals of diagonal type Lie algebras are characterized in terms of left and right ideals of the enveloping algebra. Regular inner ideals of finitary simple Lie algebras are described.

math.RT↗