Tootfinder

This https://arxiv.org/abs/2011.03619 has been replaced.
link: https://scholar.google.com/scholar?q=a

Algorithmic Extensions of Dirac's Theorem
In 1952, Dirac proved the following theorem about long cycles in graphs with large minimum vertex degrees: Every $n$-vertex $2$-connected graph $G$ with minimum vertex degree $δ\geq 2$ contains a cycle with at least $\min\{2δ,n\}$ vertices. In particular, if $δ\geq n/2$, then $G$ is Hamiltonian. The proof of Dirac's theorem is constructive, and it yields an algorithm computing the corresponding cycle in polynomial time. The combinatorial bound of Dirac's theorem is tight in the following sen…

Sharp spectral transition for embedded eigenvalues of perturbed periodic Dirac operators
Kang Lyu, Chuanfu Yang
https://arxiv.org/abs/2404.08218 https://…

Sharp spectral transition for embedded eigenvalues of perturbed periodic Dirac operators
We consider the Dirac equation on $L^2(\mathbb{R})\oplus L^2(\mathbb{R})$ \begin{align} Ly= \begin{pmatrix} 0&-1 1&0 \end{pmatrix} \begin{pmatrix} y_1 y_2 \end{pmatrix}'+ \begin{pmatrix} p&q q&-p \end{pmatrix}\begin{pmatrix} y_1 y_2 \end{pmatrix}+ V\begin{pmatrix} y_1 y_2 \end{pmatrix}=λy,\nonumber \end{align} where $y=y(x,λ)=\tbinom{y_1(x,λ)}{y_2(x,λ)}$, $p$ and $q$ are real $1$-periodic, and \begin{align} V=\begin{pmatrix} V(x)&0 0&-V(…

This https://arxiv.org/abs/2402.01042 has been replaced.
link: https://scholar.google.com/scholar?q=a

Nonlinear electrodynamics for the vacuum of Dirac materials. Photon magnetic properties and radiation pressures
We investigate the magnetic properties of photons propagating through Dirac materials in the presence of a magnetic field, taking into account both medium and vacuum contributions. The vacuum photon propagation properties are obtained through a second-order expansion of nonlinear Euler-Heisenberg electrodynamics considering Dirac material parameters (effective structure constant, band gap and Fermi velocity, respectively). Total magnetization and effective magnetic moment are obtained. Observab…

Resolving the paradox of the Dirac equation: phenomenology
Serge F. Timashev
https://arxiv.org/abs/2404.08009 https://arxiv.org/pdf/2…

Resolving the paradox of the Dirac equation: phenomenology
Based on the results of F. Wilf on the need to take into account the quantum-mechanical correspondence rules in the Dirac equation for an electron, it was shown that the equation obtained by giving physical meaning to $α$-Dirac operators should be considered as a phenomenological equation for a particle of non-zero size - the EM polaron, previously introduced by the author. This allows a solution to be found to the inherent paradox of the Dirac equation, which consists of the equality of the v…

This https://arxiv.org/abs/2212.12451 has been replaced.
link: https://scholar.google.com/scholar?q=a

Two families of Dirac-like operators for Drinfeld's Hecke algebra
In this paper, we define two generalisations of Dirac operators for Drinfeld's Hecke algebra. One generalisation, Parthasarathy operators inherit the notion of the Dirac inequality. The second generalisation, warped Dirac operators are such that every unitary module must have a non-zero warped Dirac cohomology. An open question is whether non-zero warped Dirac cohomology can determine the infinitesimal character akin to the fact that non-zero Dirac cohomology does. For a type $A$ Hecke algebra …

Quantum Theory of Phonon Induced Anomalous Hall Effect in 2D Massive Dirac metals
Jia-Xing Zhang, Wei Chen
https://arxiv.org/abs/2402.09049 https://…

Quantum Theory of Phonon Induced Anomalous Hall Effect in 2D Massive Dirac metals
The phonon induced anomalous Hall or thermal Hall effects have been observed in various systems in recent experiments. However, the theoretical studies on this subject are very scarce and incomplete. In this work, we present a systematic quantum field theory study on the phonon induced anomalous Hall effect, including both the side jump and skew scattering contributions, in a 2D massive Dirac metal, which is considered as the minimum anomalous Hall system. We reveal significant difference from …

This https://arxiv.org/abs/2309.17208 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

On the regularity of Dirac eigenfunctions
The article provides proofs for the regularity of Dirac eigenfunctions, subject to MIT boundary conditions employed on various types of open sets ranging from smooth ones to convex polygons in two dimensions, as well as on half-space and smooth bounded domains in three-dimensional space.

This https://arxiv.org/abs/2404.00444 has been replaced.
link: https://scholar.google.com/scholar?q=a

A new method for the solution of the two-body Dirac equation: Estimation of the weights of $C$, $P$ and $CP$ symmetry violating terms in positronium
A new theoretical method is developed for the solution of the two-body bound-state Dirac equation for positronium. Only Coulomb potential was included in the Dirac Hamiltonian. It is shown that the two-body Dirac Hamiltonian can be written in the Hermitian matrix form of the $4\times 4$ size and contains terms, responsible for the violation of the $P$, $C$, and $CP$ symmetries. Numerical results for the energy spectrum of the para- and ortho-positronium ground states performed within the variat…

This https://arxiv.org/abs/2111.06710 has been replaced.
link: https://scholar.google.com/scholar?q=a

Pósa-type results for Berge-hypergraphs
A Berge cycle of length $k$ in a hypergraph $\mathcal H$ is a sequence of distinct vertices and hyperedges $v_1,h_1,v_2,h_2,\dots,v_{k},h_k$ such that $v_{i},v_{i+1}\in h_i$ for all $i\in[k]$, indices taken modulo $k$. Füredi, Kostochka and Luo recently gave sharp Dirac-type minimum degree conditions that force non-uniform hypergraphs to have Hamiltonian Berge cycles. We give a sharp Pósa-type lower bound for $r$-uniform and non-uniform hypergraphs that force Hamiltonian Berge cycles.

This https://arxiv.org/abs/2402.07965 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_grqc_…

Extension of Theory of Gravitomagnetism and Spinor Quantum Mechanics with Dynamics of Free Electromagnetic Field
The theory of Gravitomagnetism and spinor quantum mechanics describing the interaction between the Dirac spinor field, the electromagnetic field, and a weak gravitational field is extended by including the Lagrangian density of the free electromagnetic field. It is shown that the newly added term in the Lagrangian density is necessary to restore a symmetric energy-momentum tensor in the interaction term of the Lagrangian density within the theory. We prove that when the electromagnetic energy t…

Kirkwood-Dirac representations beyond quantum states (and their relation to noncontextuality)
David Schmid, Roberto D. Baldij\~ao, Y\`il\`e Y\=ing, Rafael Wagner, John H. Selby
https://arxiv.org/abs/2405.04573

Kirkwood-Dirac representations beyond quantum states (and their relation to noncontextuality)
Kirkwood-Dirac representations of quantum states are increasingly finding use in many areas within quantum theory. Usually, representations of this sort are only applied to provide a representation of quantum states (as complex functions over some set). We show how standard Kirkwood-Dirac representations can be extended to a fully compositional representation of all of quantum theory (including channels, measurements and so on), and prove that this extension satisfies the essential features of …

This https://arxiv.org/abs/2310.03542 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hep…

Localization of Dirac modes in the $\mathrm{SU}(2)$ Higgs model at finite temperature
We investigate the connection between localization of low-lying Dirac modes and Polyakov-loop ordering in the lattice $\mathrm{SU}(2)$ Higgs model at finite temperature, probed with the staggered Dirac operator. After mapping out the phase diagram of the model at a fixed temporal extension in lattice units, we study the localization properties of the low-lying modes of the staggered Dirac operator, how these properties change across the various transitions, and how these modes correlate with th…

Origin of light-induced metastability in ZrTe$_5$
D. Nevola, N. Aryal, G. D. Gu, P. D. Johnson, W. -G. Yin, Q. Li
https://arxiv.org/abs/2403.08881 https://…

Origin of light-induced metastability in ZrTe$_5$
We study the non-equilibrium electronic structure of a model Dirac semimetal ZrTe$_5$ by using time-and-angle resolved photoemission spectroscopy and density functional theory-based electron and phonon calculations. By measuring the electronic dispersion near the $Γ$ point at time delays up to 10 picoseconds, we discovered that the band spectral weight does not recover during the measured temporal window, revealing the existence of light induced metastable state in the electronic structure of …

This https://arxiv.org/abs/2309.17208 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

On the regularity of Dirac eigenfunctions
The article provides proofs for the regularity of Dirac eigenfunctions, subject to MIT boundary conditions employed on various types of open sets ranging from smooth ones to convex polygons in two dimensions, as well as on half-space and smooth bounded domains in three-dimensional space.

Spectral parameter power series representation for regular solutions of the radial Dirac system
Emmanuel Roque, Sergii M. Torba
https://arxiv.org/abs/2405.06809

On spontaneous breaking of the $\text{SO}(2N)$ symmetry in the Gross-Neveu model
SangEun Han, Igor F. Herbut
https://arxiv.org/abs/2403.09627 https://

On spontaneous breaking of the $\text{SO}(2N)$ symmetry in the Gross-Neveu model
The canonical Gross-Neveu model for $N$ two-component Dirac fermions in $2+1$ dimensions suffers a continuous phase transition at a critical interaction $g_{c1} \sim 1/N$ at large $N$, at which its continuous symmetry $\text{SO}(2N)$ is preserved and a discrete (Ising) symmetry becomes spontaneously broken. A recent mean-field calculation, however, points to an additional transition at a diffferent critical $g_{c2}\sim -N g_{c1}$, at which $\text{SO}(2N) \rightarrow \text{SO}(N) \times \text{SO…

Paley-Wiener Type Theorems associated to Dirac Operators of Riesz-Feller type
Swanhild Bernstein, Nelson Faustino
https://arxiv.org/abs/2405.04989 https://…

Paley-Wiener Type Theorems associated to Dirac Operators of Riesz-Feller type
This paper systematically investigates Paley-Wiener-type theorems in the context of hypercomplex variables. To this end, we introduce and study the so-called generalized Bernstein spaces endowed by the fractional Dirac operator $D_α^θ$ - a space-fractional operator of order $α$ and skewness $θ$, encompassing the Dirac operator $D$. We will show that such family of function spaces seamlessly characterizes the interplay between Clifford-valued $L^p-$functions satisfying the support condition …

This https://arxiv.org/abs/2308.12718 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hepp…

Chiral perturbative reconstruction of the complex orthogonal matrix $R$ in Casas--Ibarra parameterization
In this letter, we perform a chiral perturbative analysis by singular values $m_{Di}$ of the Dirac mass matrix $m_{D}$ for the type-I seesaw mechanism. In the basis where $m_{D} = V m_{D}^{\rm diag} U^{\dagger}$ is diagonal, the mass matrix of right-handed neutrinos $M_{R}$ is written by $M_{R} = m_{D}^{\rm diag} m^{-1} m_{D}^{\rm diag}$. If the mass matrix of light neutrinos $m$ has an inverse matrix and the singular values $m_{Di}$ are hierarchical ($m_{D1} \ll m_{D2} \ll m_{D3}$), the singul…

This https://arxiv.org/abs/2309.17208 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

On the regularity of Dirac eigenfunctions
The article provides proofs for the regularity of Dirac eigenfunctions, subject to MIT boundary conditions employed on various types of open sets ranging from smooth ones to convex polygons in two dimensions, as well as on half-space and smooth bounded domains in three-dimensional space.

This https://arxiv.org/abs/2310.06748 has been replaced.
initial toot: https://mastoxiv.page/@arX…

Monopoles in Dirac spin liquids and their symmetries from instanton calculus
The Dirac spin liquid (DSL) is a two-dimensional (2D) fractionalized Mott insulator featuring massless Dirac spinon excitations coupled to a compact $U(1)$ gauge field, which allows for flux-tunneling instanton events described by magnetic monopoles in (2+1)D Euclidean spacetime. The state-operator correspondence of conformal field theory has been used recently to define associated monopole operators and determine their quantum numbers, which encode the microscopic symmetries of conventional or…

Entanglement entropy in the ground state of non-interacting massless Dirac fermions in dimension one
Fabrizio Ferro, Paul Pfeiffer, Wolfgang Spitzer
https://arxiv.org/abs/2404.07068

Entanglement entropy in the ground state of non-interacting massless Dirac fermions in dimension one
We present a novel proof of a formula of Casini and Huerta for the entanglement entropy of the ground state of non-interacting massless Dirac fermions in dimension one localized to (a union of) intervals and generalize it to the case of Rényi entropies. At first, we prove that these entropies are well-defined for non-intersecting intervals. This is accomplished by an inequality of Alexander V.~Sobolev. Then we compute this entropy using a trace formula for Wiener--Hopf operators by Harold Wido…

Quantum entropy couples matter with geometry
Ginestra Bianconi
https://arxiv.org/abs/2404.08556 https://arxiv.org/pdf/2404.08556

Quantum entropy couples matter with geometry
We propose a theory for coupling matter fields with discrete geometry on higher-order networks, i.e. cell complexes. The key idea of the approach is to associate to a higher-order network the quantum entropy of its metric. Specifically we propose an action given by the quantum relative entropy between the metric of the higher-order network and the metric induced by the matter and gauge fields. The induced metric is defined in terms of the topological spinors and the discrete Dirac operators. Th…

Hybrid-order topology with tunable chiral hinge modes and unpinned Dirac surface states in the altermagnetic insulator Eu$_{3}$In$_{2}$As$_{4}$
Yufei Zhao, Hyeonhu Bae, Yiyang Jiang, Yongkang Li, Chao-Xing Liu, Binghai Yan
https://arxiv.org/abs/2403.06304

Hybrid-order topology with tunable chiral hinge modes and unpinned Dirac surface states in the altermagnetic insulator Eu$_{3}$In$_{2}$As$_{4}$
The exploration of magnetic topological states is instrumental in exploring axion electrodynamics and intriguing transport phenomena, such as the quantum anomalous Hall effect. Here, we predict that the recently-synthesized material Eu$_{3}$In$_{2}$As$_{4}$ exhibits as both an axion insulator and a 3D Stiefel-Whitney insulator with an altermagnetic order. When spins align in the $ab$ plane, we find an unpinned surface Dirac cone on the $ab$ plane and chiral hinge states along the $c$ direction,…

Dirac cohomology, branching laws and Wallach modules
Chao-Ping Dong, Yongzhi Luan, Haojun Xu
https://arxiv.org/abs/2404.03918 https://

Dirac cohomology, branching laws and Wallach modules
The idea of using Dirac cohomology to study branching laws was initiated by Huang, Pandzić and Zhu in 2013 [HPZ]. One of their results says that the Dirac cohomology of $π$ completely determines $π|_{K}$, where $π$ is any irreducible unitarizable highest weight $(\mathfrak{g}, K)$ module. This paper aims to develop this idea for the exceptional Lie groups $E_{6(-14)}$ and $E_{7(-25)}$: we recover the $K$-spectrum of the Wallach modules from their Dirac cohomology.

Can the Dirac deltas in dipole fields be ignored in classical interactions?
Thales Azevedo
https://arxiv.org/abs/2403.05537 https://a…

Can the Dirac deltas in dipole fields be ignored in classical interactions?
When studying (or teaching) classical electromagnetism, one is bound to deal with the electric field of an ideal electric dipole, as well as its magnetic counterpart. A careful analysis then reveals that each of those fields must include, for consistency, a term proportional to a Dirac delta function localized at the position of the dipole. However, one is usually told not to worry about those terms since, as classical interactions always involve sources which are spatially separated, the Dirac…

This https://arxiv.org/abs/2305.14923 has been replaced.
initial toot: https://mastoxiv.page/@a…

Faraday rotation and transmittance as markers of topological phase transitions in 2D materials
We analyze the magneto-optical conductivity (and related magnitudes like transmittance and Faraday rotation of the irradiated polarized light) of some elemental two-dimensional Dirac materials of group IV (graphene analogues, buckled honeycomb lattices, like silicene, germanene, stannane, etc.), group V (phosphorene), and zincblende heterostructures (like HgTe/CdTe quantum wells) near the Dirac and gamma points, under out-of-plane magnetic and electric fields, to characterize topological-band i…

Constraining dark matter model using 21cm line intensity mapping
Koya Murakami, Kenji Kadota, Atsushi J. Nishizawa, Kentaro Nagamine, Ikkoh Shimizu
https://arxiv.org/abs/2403.06203

Constraining dark matter model using 21cm line intensity mapping
We apply the Convolutional Neural Networks (CNNs) to the mock 21cm maps from the post-reionization epoch to show that the $Λ$CDM and warm dark matter (WDM) model can be distinguished for WDM particle masses $m_{FD}<3$ keV, under the assumption of thermal production of WDM following the Fermi-Dirac (FD) distribution. We demonstrate that the CNN is a potent tool in distinguishing the dark matter masses, highlighting its sensitivity to the subtle differences in the 21cm maps produced by varying d…

Hybrid-order topology with tunable chiral hinge modes and unpinned Dirac surface states in the altermagnetic insulator Eu$_{3}$In$_{2}$As$_{4}$
Yufei Zhao, Hyeonhu Bae, Yiyang Jiang, Yongkang Li, Chao-Xing Liu, Binghai Yan
https://arxiv.org/abs/2403.06304

Hybrid-order topology with tunable chiral hinge modes and unpinned Dirac surface states in the altermagnetic insulator Eu$_{3}$In$_{2}$As$_{4}$
The exploration of magnetic topological states is instrumental in exploring axion electrodynamics and intriguing transport phenomena, such as the quantum anomalous Hall effect. Here, we predict that the recently-synthesized material Eu$_{3}$In$_{2}$As$_{4}$ exhibits as both an axion insulator and a 3D Stiefel-Whitney insulator with an altermagnetic order. When spins align in the $ab$ plane, we find an unpinned surface Dirac cone on the $ab$ plane and chiral hinge states along the $c$ direction,…

This https://arxiv.org/abs/2402.15245 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hepp…

Affleck-Dine Dirac Leptogenesis
We present a minimal framework that realises successful Dirac Leptogenesis through the Affleck-Dine mechanism. A single right-handed neutrino and a neutrinophillic Higgs doublet are introduced to the Standard Model, which couple via a Yukawa interaction. The inflationary setting is induced by a combination of the two Higgs doublets, with their global symmetry violating interactions leading to a net charge generation via the Affleck-Dine mechanism. This simple Standard Model extension exhibits a…

Braided coproduct, antipode and adjoint action for $U_q(sl_2)$
Pavle Pand\v{z}i\'c, Petr Somberg
https://arxiv.org/abs/2404.06871 https://

Braided coproduct, antipode and adjoint action for $U_q(sl_2)$
Motivated by our attempts to construct an analogue of the Dirac operator in the setting of $U_q(\mathfrak{sl}_n)$, we write down explicitly the braided coproduct, antipode, and adjoint action for quantum algebra $U_q(\mathfrak{sl}_2)$. The braided adjoint action is seen to coincide with the ordinary quantum adjoint action, which also follows from the general results of S. Majid.

Spectral Theory of Dirac Operators
Tigran Harutyunyan, Yuri Ashrafyan
https://arxiv.org/abs/2403.02761 https://arxiv.org/pdf/2403.027…

Spectral Theory of Dirac Operators
The main issues of the spectral theory of Dirac operators are presented, namely: transformation operators, asymptotics of eigenvalues and eigenfunctions, description of symmetric and self-adjoint operators in Hilbert space, expansion in eigenfunctions, uniqueness theorems in inverse problems, constructive solution of inverse problems, description of isospectral operators, and some other questions. This book is aimed at specialists in spectral theory and graduate students of mathematics at unive…

Curvature and Weitzenbock formula for spectral triples
Bram Mesland, Adam Rennie
https://arxiv.org/abs/2404.07957 https://arxiv.org/p…

Curvature and Weitzenbock formula for spectral triples
Using the Levi-Civita connection on the noncommutative differential one-forms of a spectral triple $(\B,\H,\D)$, we define the full Riemann curvature tensor, the Ricci curvature tensor and scalar curvature. We give a definition of Dirac spectral triples and derive a general Weitzenbock formula for them. We apply these tools to $θ$-deformations of compact Riemannian manifolds. We show that the Riemann and Ricci tensors transform naturally under $θ$-deformation, whereas the connection Laplacian…

Instability of quadratic band degeneracies and the emergence of Dirac points
Jonah Chaban, Michael I. Weinstein
https://arxiv.org/abs/2404.05886 https://…

Instability of quadratic band degeneracies and the emergence of Dirac points
Consider the Schrödinger operator $H = -Δ+ V$, where the potential $V$ is $\mathbb{Z}^2$-periodic and invariant under spatial inversion, complex conjugation, and $π/2$ rotation. We show that, under typical small linear deformations of $V$, the quadratic band degeneracy points, occurring over the high-symmetry quasimomentum ${\bf M}$ (see [24, 25]) each split into two separated degeneracies over perturbed quasimomenta ${\bf D}^+$ and ${\bf D}^-$, and that these degeneracies are Dirac points. …

Deep-learning design of graphene metasurfaces for quantum control and Dirac electron holography
Chen-Di Han, Li-Li Ye, Zin Lin, Vassilios Kovanis, Ying-Cheng Lai
https://arxiv.org/abs/2405.05975

Derivation of Dirac Exchange Interaction Potential from Quantum Plasma Kinetic Theory
Fernando Haas
https://arxiv.org/abs/2405.01265 https://

Derivation of Dirac Exchange Interaction Potential from Quantum Plasma Kinetic Theory
The Dirac exchange interaction is derived from recent quantum kinetic theory for collisionless plasmas. For this purpose, the kinetic equation is written in the semiclassical and long wavelength approximations. The validity of the model for real systems is worked out, in terms of temperature and density parameters. Within the region of applicability, the correlation potential energy is shown to be always smaller than the exchange contribution. From the moments of the quantum kinetic equations, …

This https://arxiv.org/abs/2312.04012 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hep…

Weyl fermions on a finite lattice
The phenomenon of unpaired Weyl fermions appearing on the sole 2n-dimensional boundary of a (2n+1)-dimensional manifold with massive Dirac fermions was recently analyzed in a companion paper by one of the authors. In this Letter we show that similar unpaired Weyl edge states can be seen on a finite lattice. In particular, we consider the discretized Hamiltonian for a Wilson fermion in (2+1) dimensions with a 1+1 dimensional boundary and continuous time. We demonstrate that the low lying boundar…

Spectrum of the Dirac operator on Compact Riemannian Manifolds
Lingzhong Zeng
https://arxiv.org/abs/2402.14247 https://arxiv.org/pdf/…

Spectrum of the Dirac operator on Compact Riemannian Manifolds
In this paper, we consider the eigenvalue problem of Dirac operator on a compact Riemannian manifold isometrically immersed into Euclidean space and derive some extrinsic estimates for the sum of arbitrary consecutive $n$ eigenvalues of the square of the Dirac operator acting on some Dirac invariant subbundles. As some applications, we deduce some eigenvalue inequalities on the compact submanifolds immersed into Euclidean space, unit sphere or projective spaces and further get some bounds of ge…

Giant asymmetric proximity-induced spin-orbit coupling in twisted graphene/SnTe heterostructure
Marko Milivojevi\'c, Martin Gmitra, Marcin Kurpas, Ivan \v{S}tich, Jaroslav Fabian
https://arxiv.org/abs/2402.09045

Giant asymmetric proximity-induced spin-orbit coupling in twisted graphene/SnTe heterostructure
We analyze the spin-orbit coupling effects in a three-degree twisted bilayer heterostructure made of graphene and an in-plane ferroelectric SnTe, with the goal of transferring the spin-orbit coupling from SnTe to graphene, via the proximity effect. Our results indicate that the point-symmetry breaking due to the incompatible mutual symmetry of the twisted monolayers and a strong hybridization has a massive impact on the spin splitting in graphene close to the Dirac point, with the spin splittin…

Spin-polarized Specular Andreev Reflections in Altermagnets
Yutaro Nagae, Andreas P. Schnyder, Satoshi Ikegaya
https://arxiv.org/abs/2403.07117 https://

Spin-polarized Specular Andreev Reflections in Altermagnets
We propose a multi-terminal device consisting of an s-wave superconductor coupled to an altermagnet, to generate highly correlated spin currents via Cooper pair splitting. Remarkably, we find that the correlated spin currents are induced by specular Andreev reflections in the altermagnet, an effect that has up to now been predicted to occur only in a very limited number of systems, e.g., Dirac/Weyl materials coupled to superconductors. We demonstrate that positive non-local charge currents and …

Exact Multi-Point Correlations in the Stochastic Heat Equation for Strictly Sublinear Coordinates
Pierre Yves Gaudreau Lamarre, Yier Lin
https://arxiv.org/abs/2403.06868

Exact Multi-Point Correlations in the Stochastic Heat Equation for Strictly Sublinear Coordinates
We consider the Stochastic Heat Equation (SHE) in $(1+1)$ dimensions with delta Dirac initial data and spacetime white noise. We prove exact large-time asymptotics for multi-point correlations of the SHE for strictly sublinear space coordinates. The sublinear condition is optimal, in the sense that different asymptotics are known to occur when the space coordinates grow linearly [Lin 2023, Theorem 1.1]. Lastly, a notable feature of our result is that it confirms the connection between multi-poi…

This https://arxiv.org/abs/2403.17029 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_qu…

Relativistic exponential-type spinor orbitals and their use in many-electron Dirac equation solution
Dirac-Coulomb type differential equation and its solution relativistic exponential-type spinor orbitals are introduced. They provide a revised form for operator invariants, namely Dirac invariants, simplifying the treatment of the angular components in calculation of many-electron systems. The relativistic Coulomb energy is determined by employing a spectral solution to Poisson's equation for the one$-$electron potential, which is expressed in terms of radial functions involving incomplete gamm…

This https://arxiv.org/abs/2312.07791 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hept…

Lorentz invariance violation and the CPT-odd electromagnetic response of a tilted anisotropic Weyl semimetal
We derive the electromagnetic response of a particular fermionic sector in the minimal QED contribution to the Standard Model Extension (SME), which can be physically realized in terms of a model describing a tilted and anisotropic Weyl semimetal (WSM). The contact is made through the identification of the Dirac-like Hamiltonian resulting from the SME with that corresponding to the WSM in the linearized tight-binding approximation. We first calculate the effective action by computing the non-pe…

On monogenic functions and the Dirac complex of two vector variables
Yun Shi, Wei Wang, Qingyan Wu
https://arxiv.org/abs/2404.03374 https://

On monogenic functions and the Dirac complex of two vector variables
A monogenic function of two vector variables is a function annihilated by the operator consisting of two Dirac operators, which are associated to two variables, respectively. We give the explicit form of differential operators in the Dirac complex resolving this operator and prove its ellipticity directly. This open the door to apply the method of several complex variables to investigate this kind of monogenic functions. We prove the Poincaré lemma for this complex, i.e. the non-homogeneous eq…

Lattice dynamics of altermagnetic ruthenium oxide RuO$_{2}$
Surajit Basak, Andrzej Ptok
https://arxiv.org/abs/2403.07609 https://arxi…

Lattice dynamics of altermagnetic ruthenium oxide RuO$_{2}$
Altermagnetic ruthenium oxide RuO$_{2}$ crystallizes with P4$_{2}$/mnm symmetry. Here we discuss the lattice dynamics of this structure. We show and discuss the phonon dispersion and density of states. The phonon dispersion curves contain several Dirac nodal lines and highly degenerate Dirac points. We present the characteristic frequencies and their irreducible representations at the $Γ$ point. Theoretically obtained frequencies of the Raman active modes nicely reproduce the ones reported exp…

This https://arxiv.org/abs/1812.09669 has been replaced.
link: https://scholar.google.com/scholar?q=a

Pauli-type coupling between spinors and curved spacetime
In this study we prove that the Pauli interaction emerges when the minimal coupling recipe is applied to the non-degenerate version of the Dirac Lagrangian. The conventional Dirac Lagrangian is rendered non-degenerate if supplemented by a particular term quadratic in the derivatives of the spinors. For dimensional reasons, this non-degenerate Dirac Lagrangian is associated with a length parameter $\ell$. It yields the standard free Dirac equation in Minkowski space. However, if the Dirac spinor…

Chordal matroids arising from generalized parallel connections II
James Dylan Douthitt, James Oxley
https://arxiv.org/abs/2405.02099 https://

Chordal matroids arising from generalized parallel connections II
In 1961, Dirac showed that chordal graphs are exactly the graphs that can be constructed from complete graphs by a sequence of clique-sums. In an earlier paper, by analogy with Dirac's result, we introduced the class of $GF(q)$-chordal matroids as those matroids that can be constructed from projective geometries over $GF(q)$ by a sequence of generalized parallel connections across projective geometries over $GF(q)$. Our main result showed that when $q=2$, such matroids have no induced minor in …

Lattice dynamics of altermagnetic ruthenium oxide RuO$_{2}$
Surajit Basak, Andrzej Ptok
https://arxiv.org/abs/2403.07609 https://arxi…

Lattice dynamics of altermagnetic ruthenium oxide RuO$_{2}$
Altermagnetic ruthenium oxide RuO$_{2}$ crystallizes with P4$_{2}$/mnm symmetry. Here we discuss the lattice dynamics of this structure. We show and discuss the phonon dispersion and density of states. The phonon dispersion curves contain several Dirac nodal lines and highly degenerate Dirac points. We present the characteristic frequencies and their irreducible representations at the $Γ$ point. Theoretically obtained frequencies of the Raman active modes nicely reproduce the ones reported exp…

This https://arxiv.org/abs/2402.12456 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hept…

Three point interaction of Dirac fermions with higher spin particles and discrete symmetries
We constructed all possible kinematically allowed three-point interactions of two massless Dirac spinors with massive higher-spin bosons. In any $D$ spacetime, the interactions have been constructed using the projections of the massive higher spin representations of $Spin(D-1)$ over the massless complex spinor representations of $Spin(D-2)\times Spin(D-2)$. Based on this analysis, we have further classified the space of theories involving one massless Dirac spinor and a single (or multiple) mas…

Classifying bulk-edge anomalies in the Dirac Hamiltonian
Hansueli Jud, Cl\'ement Tauber
https://arxiv.org/abs/2403.04465 https://…

Classifying bulk-edge anomalies in the Dirac Hamiltonian
We study the Dirac Hamiltonian in dimension two with a mass term and a large momentum regularization, and show that bulk-edge correspondence fails. Despite a well defined bulk topological index --the Chern number--, the number of edge modes depends on the boundary condition. The origin of this anomaly is rooted in the unbounded nature of the spectrum. It is detected with Levinson's theorem from scattering theory and quantified via an anomalous winding number at infinite energy, dubbed ghost cha…

Braided coproduct, antipode and adjoint action for $U_q(sl_2)$
Pavle Pand\v{z}i\'c, Petr Somberg
https://arxiv.org/abs/2404.06871 https://

Braided coproduct, antipode and adjoint action for $U_q(sl_2)$
Motivated by our attempts to construct an analogue of the Dirac operator in the setting of $U_q(\mathfrak{sl}_n)$, we write down explicitly the braided coproduct, antipode, and adjoint action for quantum algebra $U_q(\mathfrak{sl}_2)$. The braided adjoint action is seen to coincide with the ordinary quantum adjoint action, which also follows from the general results of S. Majid.

Electric dipole moments of charged leptons in models with pseudo-Dirac sterile fermions
Asmaa Abada, Takashi Toma
https://arxiv.org/abs/2405.01648 https://…

Electric dipole moments of charged leptons in models with pseudo-Dirac sterile fermions
In this work, we address the impact of a small lepton number violation on charged lepton electric dipole moments - EDMs. Low-scale seesaw models protected by lepton number symmetry and leading to pseudo-Dirac pairs in the neutrino heavy spectrum provide a natural explanation for the smallness of neutrino masses with potentially testable consequences. Among which, it was thought that the small mass gap in each pair of pseudo-Dirac neutrinos may induce important contribution to the charged lepton…

Orbital and spin bilinear magnetotransport effect in Weyl/Dirac semimetal
Zhanyunxin Du, Yue-Xin Huang, Xiao Li
https://arxiv.org/abs/2404.07858 https://…

Orbital and spin bilinear magnetotransport effect in Weyl/Dirac semimetal
We theoretically investigate the bilinear current, scaling as $j\sim EB$, in two- and three-dimensional systems. Based on the extended semiclassical theory, we develop a unified theory including both longitudinal and transverse currents. We classify all contributions according to their different scaling relations with the relaxation time. We reveal the distinct contributions to the ordinary Hall effect, planar Hall effect, and magnetoresistance. We further report an intrinsic ordinary Hall curr…

Toroidal orders and related phenomena in nonmagnetic and magnetic materials
Hiroaki Kusunose, Satoru Hayami
https://arxiv.org/abs/2403.09492 https://

Toroidal orders and related phenomena in nonmagnetic and magnetic materials
In this short article, we overview a concept of electronic toroidal multipoles, and their ordering with associated physical properties in non-magnetic and magnetic materials. The toroidal multipoles are introduced as microscopic electronic variables in view of symmetry and connection to Dirac theory. They are classified according to crystallographic and magnetic point groups, which allows us to discuss various possible cross correlations in a transparent and unified manner. The representative e…

Classifying bulk-edge anomalies in the Dirac Hamiltonian
Hansueli Jud, Cl\'ement Tauber
https://arxiv.org/abs/2403.04465 https://…

Classifying bulk-edge anomalies in the Dirac Hamiltonian
We study the Dirac Hamiltonian in dimension two with a mass term and a large momentum regularization, and show that bulk-edge correspondence fails. Despite a well defined bulk topological index --the Chern number--, the number of edge modes depends on the boundary condition. The origin of this anomaly is rooted in the unbounded nature of the spectrum. It is detected with Levinson's theorem from scattering theory and quantified via an anomalous winding number at infinite energy, dubbed ghost cha…

Equivariant Spectral Flow for Families of Dirac-type Operators
Peter Hochs, Aquerman Yanes
https://arxiv.org/abs/2403.00575 https://a…

Equivariant Spectral Flow for Families of Dirac-type Operators
In the setting of a proper, cocompact action by a locally compact, unimodular group $G$ on a Riemannian manifold, we construct equivariant spectral flow of paths of Dirac-type operators. This takes values in the $K$-theory of the group $C^*$-algebra of $G$. In the case where $G$ is the fundamental group of a compact manifold, the summation map maps equivariant spectral flow on the universal cover to classical spectral flow on the base manifold. We obtain "index equals spectral flow" results. In…

This https://arxiv.org/abs/2401.04684 has been replaced.
initial toot: https://mastoxiv.page/@a…

Emergence of Larkin-Ovchinnikov-type superconducting state in a voltage-driven superconductor
We theoretically investigate a voltage-biased normal metal-superconductor-normal metal (N-S-N) junction. Using the nonequilibrium Green's function technique, we derive a quantum kinetic equation, to determine the superconducting order parameter self-consistently. The derived equation is an integral-differential equation with memory effects. We solve this equation by converting it into a system of ordinary differential equations with the use of a pole expansion of the Fermi-Dirac function. When …

This https://arxiv.org/abs/2402.18893 has been replaced.
initial toot: https://mastoxiv.page/@arX…

Direct Visualization of Disorder Driven Electronic Liquid Crystal Phases in Dirac Nodal Line Semimetal GdSbTe
Electronic liquid crystal (ELC) phases are spontaneous symmetry breaking states believed to arise from strong electron correlation in quantum materials such as cuprates and iron pnictides. Here, we report a direct observation of ELC phases in a Dirac nodal line (DNL) semimetal GdSbxTe2-x. Electronic nanostructures consisting of incommensurate smectic charge modulation and intense local nematic order are visualized by using spectroscopic imaging - scanning tunneling microscopy. As topological ma…

Re-assessing special aspects of Dirac fermions in presence of Lorentz-symmetry violation
Jo\~ao Paulo S. Melo, Jos\'e A. Helay\"el-Neto
https://arxiv.org/abs/2404.03692 <…

Re-assessing special aspects of Dirac fermions in presence of Lorentz-symmetry violation
This paper focuses on additional inspections concerning the fermionic sector of the Standard Model Extension (SME). In this context, our main effort in this contribution is to investigate effects of Lorentz-symmetry violation (LSV) on the Klein Paradox, the Zitterbewegung and its phenomenology in connection to Condensed Matter Physics, Atomic Physics, and Astrophysics. Finally, we discuss a particular realization of LSV in the Dirac equation, considering an asymmetry between space and time due …

Dirac cohomology of minimal representations
Xuanchen Zhao
https://arxiv.org/abs/2404.17408 https://arxiv.org/pdf/2404.17408

Dirac cohomology of minimal representations
In this paper, we study the Dirac cohomology of minimal representations for all real reductive groups G. The Dirac indices of these representations are also studied when G is of equal rank, giving some counterexamples of a conjecture of Huang proposed in 2015.

Dirac fermions collimation in heterostructures based on tilted Dirac cone materials
Ej Bou\^azzaoui Choubabi, Bouchaib Lemaalem, Mohamed Raggui, Abdelhadi Belouad, Rachid Hou\c{c}a, Abdellatif Kamal, Mohamed Monkade
https://arxiv.org/abs/2404.02485

Dirac fermions collimation in heterostructures based on tilted Dirac cone materials
This paper aims to theoretically analyze the behavior of Dirac fermions in tilted Dirac cone material, particularly those that have diffused a barrier potential.Our results show that the degree of tilt in the y-direction can lead to different collimations of the Dirac fermion beams relative to the Fermi and confinement surfaces. To study the transmission probability, we exploited our results numerically, taking into account the various configurations of the system and the different external and…

Dirac-type Theorems for Inhomogenous Random Graphs
Ghurumuruhan Ganesan
https://arxiv.org/abs/2404.02267 https://arxiv.org/pdf/2404.0…

Dirac-type Theorems for Inhomogenous Random Graphs
In this paper, we study Dirac-type theorems for an inhomogenous random graph (G) whose edge probabilities are not necessarily all the same. We obtain sufficient conditions for the existence of Hamiltonian paths and perfect matchings, in terms of the \emph{sum} of edge probabilities. For edge probability assignments with two-sided bounds, we use Pósa rotation and single vertex exclusion techniques to show that (G) is Hamiltonian with high probability. For weaker one-sided bounds, we use bootstr…

This https://arxiv.org/abs/2403.17029 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_qu…

Relativistic exponential-type spinor orbitals and their use in many-electron Dirac equation solution
Dirac-Coulomb type differential equation and its solution relativistic exponential-type spinor orbitals are introduced. They provide a revised form for operator invariants, namely Dirac invariants, simplifying the treatment of the angular components in calculation of many-electron systems. The relativistic Coulomb energy is determined by employing a spectral solution to Poisson's equation for the one$-$electron potential, which is expressed in terms of radial functions involving incomplete gamm…

Degree sequence condition for Hamiltonicity in tough graphs
Songling Shan, Arthur Tanyel
https://arxiv.org/abs/2405.04728 https://arx…

Degree sequence condition for Hamiltonicity in tough graphs
Generalizing both Dirac's condition and Ore's condition for Hamilton cycles, Chvatal in 1972 established a degree sequence condition for the existence of a Hamilton cycle in a graph. Hoang in 1995 generalized Chvatal's degree sequence condition for 1-tough graphs and conjectured a t-tough analogue for any positive integer t at least 1. Hoang in the same paper verified his conjecture for t at most 3 and recently Hoang and Robin arXiv:2303.03479v2 verified the conjecture for t = 4. In this paper,…

Seebeck Effect of Dirac Electrons in Organic Conductors under Hydrostatic Pressure Using a Tight-Binding Model Derived from First Principles
Yoshikazu Suzumura, Takao Tsumuraya, Masao Ogata
https://arxiv.org/abs/2404.05914

Seebeck Effect of Dirac Electrons in Organic Conductors under Hydrostatic Pressure Using a Tight-Binding Model Derived from First Principles
The Seebeck coefficient is examined for two-dimensional Dirac electrons in the three-quarter filled organic conductor alpha-(BEDT-TTF)_2I_3 under hydrostatic pressure, where the Seebeck coefficient is proportional to the ratio of the thermoelectric conductivity to the electrical conductivity. We present an improved tight-binding model in two dimensions with transfer energies determined from first-principles density functional theory calculations with an experimentally determined crystal structu…

This https://arxiv.org/abs/2209.09181 has been replaced.
link: https://scholar.google.com/scholar?q=a

The Dirac equation across the horizons of the 5D Myers-Perry geometry : Separation of variables, radial asymptotic behaviour and Hamiltonian formalism
We analytically extend the 5D Myers-Perry metric through the event and Cauchy horizons by defining Eddington-Finkelstein-type coordinates. Then, we use the orthonormal frame formalism to formulate and perform separation of variables on the massive Dirac equation, and analyse the asymptotic behaviour at the horizons and at infinity of the solutions to the radial ordinary differential equation (ODE) thus obtained. Using the essential self-adjointness result of Finster and Röken and Stone's formu…

This https://arxiv.org/abs/2312.02857 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hep…

Continuum limit of the mobility edge and taste-degeneracy effects in high-temperature lattice QCD with staggered quarks
We study the effects of taste degeneracy on the continuum scaling of the localization properties of the staggered Dirac operator in high-temperature QCD using numerical simulations on the lattice, focusing in particular on the position of the mobility edge separating localized and delocalized modes at the low end of the spectrum. We find that, if the continuum limit is approached at fixed spatial volume, the restoration of taste symmetry leads to sizeable systematic effects on estimates for the…

Emergent Elastic Surfaces from Two-Dimensional Dirac Materials
Pablo A. Morales, Pavel Castro-Villareal
https://arxiv.org/abs/2404.02741 https://

Emergent Elastic Surfaces from Two-Dimensional Dirac Materials
Temperature constraints are highly desirable in the experimental setup when seeking the synthesis of new carbon structures. Fluctuations of the Dirac field result in temperature-dependent corrections to the Helfrich-Canham formulation, which governs the classical elasticity of the membrane in equilibrium state. Here, we examine the emergent shapes allowed by the effective model up to quadratic order in Ricci curvature and discuss the constraints required to observe them. We determine the mechan…

Solar neutrinos and leptonic spin forces
Saeed Ansarifard, M. C. Gonzalez-Garcia, Michele Maltoni, Joao Paulo Pinheiro
https://arxiv.org/abs/2405.05340 htt…

Solar neutrinos and leptonic spin forces
We quantify the effects on the evolution of solar neutrinos of light spin-zero particles with pseudoscalar couplings to leptons and scalar couplings to nucleons. In this scenario the matter potential sourced by the nucleons in the Sun's matter gives rise to spin precession of the relativistic neutrino ensemble. As such the effects in the solar observables are different if neutrinos are Dirac or Majorana particles. For Dirac neutrinos the spin-flavour precession results into left-handed neutrino…

Large N limit of fuzzy geometries coupled to fermions
Masoud Khalkhali, Nathan Pagliaroli, Luuk S. Verhoeven
https://arxiv.org/abs/2405.05056 https://

Large N limit of fuzzy geometries coupled to fermions
In this paper we present an analysis of the large N limit of a family of quartic Dirac ensembles based on (0, 1) fuzzy geometries that are coupled to fermions. These Dirac ensembles are examples of single-matrix, multi-trace matrix ensembles. Additionally, they serve as examples of integer-valued $β$-ensembles. Convergence of the spectral density in the large N limit for a large class of such matrix ensembles is proven, improving on existing results. The main results of this paper are the addi…

This https://arxiv.org/abs/2402.02477 has been replaced.
link: https://scholar.google.com/scholar?q=a

Topologically protected Casimir effect for lattice fermions
The electromagnetic Casimir effect has a fermionic counterpart in topological insulators: Zero-point fluctuations of a massless Dirac fermion field mediate a force between magnetic scatterers. The Casimir force is insensitive to disorder that preserves the topological protection of an unpaired Dirac cone. The protection may be broken if the Dirac equation is discretized, and an exponential suppression of the Casimir effect will result if a gap opens at the Dirac point. Here we show how this lat…

This https://arxiv.org/abs/2209.09181 has been replaced.
link: https://scholar.google.com/scholar?q=a

The Dirac equation across the horizons of the 5D Myers-Perry geometry : Separation of variables, radial asymptotic behaviour and Hamiltonian formalism
We analytically extend the 5D Myers-Perry metric through the event and Cauchy horizons by defining Eddington-Finkelstein-type coordinates. Then, we use the orthonormal frame formalism to formulate and perform separation of variables on the massive Dirac equation, and analyse the asymptotic behaviour at the horizons and at infinity of the solutions to the radial ordinary differential equation (ODE) thus obtained. Using the essential self-adjointness result of Finster and Röken and Stone's formu…

This https://arxiv.org/abs/2402.05172 has been replaced.
link: https://scholar.google.com/scholar?q=a

Can quantum statistics help distinguish Dirac from Majorana neutrinos?
Finding out if neutrinos are Dirac or Majorana particles is known to be extremely difficult due to the smallness of neutrino mass and the fact that in the limit $m_ν=0$ both Dirac and Majorana neutrinos become Weyl particles, i.e. are indistinguishable. There have been suggestions in the literature that in the case of processes with production of a neutrino-antineutrino pair (if neutrinos are Dirac particles) or two neutrinos (if they are of Majorana nature) quantum statistics may be of help. …

This https://arxiv.org/abs/2212.14516 has been replaced.
link: https://scholar.google.com/scholar?q=a

A hypergraph analog of Dirac's Theorem for long cycles in 2-connected graphs
Dirac proved that each $n$-vertex $2$-connected graph with minimum degree at least $k$ contains a cycle of length at least $\min\{2k, n\}$. We consider a hypergraph version of this result. A Berge cycle in a hypergraph is an alternating sequence of distinct vertices and edges $v_1,e_2,v_2, \ldots, e_c, v_1$ such that $\{v_i,v_{i+1}\} \subseteq e_i$ for all $i$ (with indices taken modulo $c$). We prove that for $n \geq k \geq r+2 \geq 5$, every $2$-connected $r$-uniform $n$-vertex hypergraph wit…

This https://arxiv.org/abs/2405.03238 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Topological Photonic Structures with Broken Reflection Symmetry
In this work, we present a mathematical theory for Dirac points and interface modes in honeycomb topological photonic structures consisting of impenetrable obstacles. Starting from a honeycomb lattice of obstacles attaining $120^\circ$-rotation symmetry and horizontal reflection symmetry, we apply the boundary integral equation method to show the existence of Dirac points for the first two bands at the vertices of the Brillouin zone. We then study interface modes in a joint honeycomb photonic s…

This https://arxiv.org/abs/2308.00798 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hepp…

How Many Dark Neutrino Sectors Does Cosmology Allow?
We present the very first constraints on the number of Standard Model (SM) copies with an additional Dirac right-handed neutrino. From cosmology, we are able to pose strong limits on large regions of the parameter space. Moreover, we show that it is possible to account for the right dark matter density in form of stable particles from the dark sectors.

This https://arxiv.org/abs/2402.07589 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hept…

New construction of a charged dipole black ring by Harrison transformation
We present an exact solution for a non-BPS charged rotating black ring endowed with a dipole charge in the bosonic sector of five-dimensional minimal supergravity. Utilizing the electric Harrison transformation, we derive this solution by converting a five-dimensional vacuum solution into a charged solution within the realm of five-dimensional minimal supergravity. As the seed solution for the Harrison transformation, we use a vacuum solution of a rotating black ring possessing a Dirac-Misner s…

This https://arxiv.org/abs/2402.11593 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_grqc_…

Spacetime geometry from Dirac spinor theory
The quintet of Dirac $4\times 4$ matrices suggests that the fundamental dimension of the internal (spin) space is $n=5$, instead of the conventional dimension $n=4$. Then extending the usual $4\times 4$ tetrads (vierbein), gravity is described in terms of the 5-bein (fünfbein or five legs). We discuss the properties of the spacetime geometry induced from this 5-leg Dirac spinor theory, where the spin connection contains $10\times 4=40$ elements instead of 24 elements in the tetrad formulation …

Tracing Dirac points of topological surface states by ferromagnetic resonance
Laura Pietanesi, Magdalena Marganska, Thomas Mayer, Michael Barth, Lin Chen, Ji Zou, Adrian Weindl, Alexander Liebig, Rebeca D\'iaz-Pardo, Dhavala Suri, Florian Schmid, Franz J. Gie{\ss}ibl, Klaus Richter, Yaroslav Tserkovnyak, Matthias Kronseder, Christian H. Back
http…

Tracing Dirac points of topological surface states by ferromagnetic resonance
Ferromagnetic resonance is used to reveal features of the buried electronic band structure at interfaces between ferromagnetic metals and topological insulators. By monitoring the evolution of magnetic damping, the application of this method to a hybrid structure consisting of a ferromagnetic layer and a 3D topological insulator reveals a clear fingerprint of the Dirac point and exhibits additional features of the interfacial band structure not otherwise observable. The underlying spin-pumping …

Dirac's theorem for linear hypergraphs
Seonghyuk Im, Hyunwoo Lee
https://arxiv.org/abs/2403.14269 https://arxiv.org/pdf/2403.1426…

Dirac's theorem for linear hypergraphs
Dirac's theorem states that any $n$-vertex graph $G$ with even integer $n$ satisfying $δ(G) \geq n/2$ contains a perfect matching. We generalize this to $k$-uniform linear hypergraphs by proving the following. Any $n$-vertex $k$-uniform linear hypergraph $H$ with minimum degree at least $\frac{n}{k} + Ω(1)$ contains a matching that covers at least $(1-o(1))n$ vertices. This minimum degree condition is asymptotically tight and obtaining perfect matching is impossible with any degree condition.…

This https://arxiv.org/abs/2312.06128 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hept…

On the Backreaction of Dirac Matter in JT Gravity and SYK Model
We model backreaction in AdS$_2$ JT gravity via a proposed boundary dual Sachdev-Ye-Kitaev quantum dot coupled to Dirac fermion matter and study it from the perspective of quantum entanglement and chaos. The boundary effective action accounts for the backreaction through a linear coupling of the Dirac fermions to the Gaussian-random two-body Majorana interaction term in the low-energy limit. We calculate the time evolution of the entanglement entropy between graviton and Dirac fermion fields fo…

This https://arxiv.org/abs/2402.11386 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hepp…

Comments on "Can quantum statistics help distinguish Dirac from Majorana neutrinos?" (arXiv:2402.05172 [hep-ph])
In a recent article arXiv:2402.05172 [hep-ph], the authors discuss the question "whether quantum statistics can help distinguish between Dirac and Majorana neutrinos." The paper contains, among other things, an unsubstantiated critique of the results derived in our papers arXiv:2106.11785 [hep-ph] and arXiv:2307.05654 [hep-ph]. One of the criticisms is related to our expression for differential decay rate for the back-to-back neutrino-antineutrino configuration in the decay $B^0 \to μ^- \, μ^…

Tracing Dirac points of topological surface states by ferromagnetic resonance
Laura Pietanesi, Magdalena Marganska, Thomas Mayer, Michael Barth, Lin Chen, Ji Zou, Adrian Weindl, Alexander Liebig, Rebeca D\'iaz-Pardo, Dhavala Suri, Florian Schmid, Franz J. Gie{\ss}ibl, Klaus Richter, Yaroslav Tserkovnyak, Matthias Kronseder, Christian H. Back
http…

Tracing Dirac points of topological surface states by ferromagnetic resonance
Ferromagnetic resonance is used to reveal features of the buried electronic band structure at interfaces between ferromagnetic metals and topological insulators. By monitoring the evolution of magnetic damping, the application of this method to a hybrid structure consisting of a ferromagnetic layer and a 3D topological insulator reveals a clear fingerprint of the Dirac point and exhibits additional features of the interfacial band structure not otherwise observable. The underlying spin-pumping …

This https://arxiv.org/abs/2402.02039 has been replaced.
link: https://scholar.google.com/scholar?q=a

Hamiltonian analysis for perturbative $λR$ gravity
The Hamiltonian analysis for the linearized $λR$ gravity around the Minkowski background is performed. The first-class and second-class constraints for arbitrary values of $λ$ are presented, and two physical degrees of freedom are reported. In addition, we remove the second-class constraints, and the generalized Dirac brackets are constructed; then, the equivalence between General Relativity and the $λR$ theory is shown.

Effect of Uncorrelated On-site Scalar Potential, and Mass Disorder on Transport of Two-Dimensional Dirac Fermions
Arman Duha, Mario Borunda
https://arxiv.org/abs/2403.03914

Effect of Uncorrelated On-site Scalar Potential, and Mass Disorder on Transport of Two-Dimensional Dirac Fermions
We investigate the transport properties of massive Dirac fermions subjected to uncorrelated scalar potential disorder, and mass disorder. Using a finite difference method, the conductance is calculated for a wide variety of combinations of these two disorder strengths. By calculating the scaling of conductivity with system size we find that, depending on the combination, the system can have an insulating, scale invariant, and metallic behavior. We identify the critical values of these disorder …

Tensor gauge fields and dark matter in general relativity with fermions
Kevin Cahill
https://arxiv.org/abs/2404.05766 https://arxiv.o…

Tensor gauge fields and dark matter in general relativity with fermions
The action of general relativity with fermions has two independent symmetries: general coordinate invariance and local Lorentz invariance. General coordinate transformations act on coordinates and tensor indices, while local Lorentz transformations act on Dirac and Lorentz indices, much like a noncompact internal symmetry. \par The internal-symmetry character of local Lorentz invariance suggests that it might be implemented by tensor gauge fields with their own Yang-Mills action rather than by …

Dirac leptogenesis from asymmetry wash-in via scatterings
Tom\'a\v{s} Bla\v{z}ek, Julian Heeck, Jan Heisig, Peter Mat\'ak, Viktor Zaujec
https://arxiv.org/abs/2404.16934 <…

Dirac leptogenesis from asymmetry wash-in via scatterings
Leptogenesis typically requires the introduction of heavy particles whose out-of-equilibrium decays are essential for generating a matter-antimatter asymmetry, according to one of Sakharov's conditions. We demonstrate that in Dirac leptogenesis, scatterings between the light degrees of freedom - Standard Model particles plus Dirac neutrinos - are sufficient to generate the asymmetry. Due to its vanishing source term in the Boltzmann equations, the asymmetry of right-handed neutrinos solely aris…

Effect of Uncorrelated On-site Scalar Potential, and Mass Disorder on Transport of Two-Dimensional Dirac Fermions
Arman Duha, Mario Borunda
https://arxiv.org/abs/2403.03914

Effect of Uncorrelated On-site Scalar Potential, and Mass Disorder on Transport of Two-Dimensional Dirac Fermions
We investigate the transport properties of massive Dirac fermions subjected to uncorrelated scalar potential disorder, and mass disorder. Using a finite difference method, the conductance is calculated for a wide variety of combinations of these two disorder strengths. By calculating the scaling of conductivity with system size we find that, depending on the combination, the system can have an insulating, scale invariant, and metallic behavior. We identify the critical values of these disorder …

Spectral properties of two-dimensional half-space semi-Dirac semi-metals
Tuyen Vu
https://arxiv.org/abs/2402.17610 https://arxiv.org/…

Spectral properties of two-dimensional half-space semi-Dirac semi-metals
The paper deals with the semi-Dirac operator in a half-space arising in the description of quasiparticles in quantum mechanics as well as in semi-metals materials and related structures. It completely shows the self-adjointness, computes the square and the spectrum of the operator. We also set up sufficient conditions for the existence of the point and discrete spectrum by including some appropriate potentials in the problem and study the spectral stability properties for perturbed operators.

This https://arxiv.org/abs/2402.02039 has been replaced.
link: https://scholar.google.com/scholar?q=a

Hamiltonian analysis for perturbative $λR$ gravity
The Hamiltonian analysis for the linearized $λR$ gravity around the Minkowski background is performed. The first-class and second-class constraints for arbitrary values of $λ$ are presented, and two physical degrees of freedom are reported. In addition, we remove the second-class constraints, and the generalized Dirac brackets are constructed; then, the equivalence between General Relativity and the $λR$ theory is shown.

Dirac leptogenesis from asymmetry wash-in via scatterings
Tom\'a\v{s} Bla\v{z}ek, Julian Heeck, Jan Heisig, Peter Mat\'ak, Viktor Zaujec
https://arxiv.org/abs/2404.16934 <…

Dirac leptogenesis from asymmetry wash-in via scatterings
Leptogenesis typically requires the introduction of heavy particles whose out-of-equilibrium decays are essential for generating a matter-antimatter asymmetry, according to one of Sakharov's conditions. We demonstrate that in Dirac leptogenesis, scatterings between the light degrees of freedom - Standard Model particles plus Dirac neutrinos - are sufficient to generate the asymmetry. Due to its vanishing source term in the Boltzmann equations, the asymmetry of right-handed neutrinos solely aris…

Coupling of Branes and Twisted Self-Duality in the Maxwell-Chern-Simons Theory
Hannes Malcha
https://arxiv.org/abs/2404.02226 https://

Coupling of Branes and Twisted Self-Duality in the Maxwell-Chern-Simons Theory
We study three approaches to electric-magnetic duality in the 4-dimensional Maxwell theory coupled to a dyonic point charge and in the 5-dimensional Maxwell-Chern-Simons (MCS) theory coupled to an electric point charge and a magnetic string charge. The three approaches have been developed by Dirac, Bunster and Henneaux, and Pasti, Sorokin and Tonin (PST). In Dirac's formulation, the electric magnetic duality is realized only on the level of the equations of motion. The other two formulations in…

Spin caloric resistance of Dirac plasma in graphene Corbino device
Alex Levchenko
https://arxiv.org/abs/2404.03135 https://arxiv.org/…

Spin caloric resistance of Dirac plasma in graphene Corbino device
The thermal resistance of a spin-polarized hydrodynamic Dirac plasma in graphene is considered. A mechanism for the coupling of heat and spin flows is discussed, demonstrating that spin diffusion and spin thermocurrent modify viscous dissipation, leading to a significant enhancement of thermal resistance. Practical calculations are then presented for graphene devices in the Corbino geometry.

Negative magnetoresistance induced by longitudinal photons in Dirac/Weyl semimetals
J. L. Acosta Avalo, H. P\'erez Rojas
https://arxiv.org/abs/2402.16859

Negative magnetoresistance induced by longitudinal photons in Dirac/Weyl semimetals
A low-energy model is built to study systems such as Dirac/Weyl semimetals, according to statistical quantum electrodynamics formalism. We report that the introduction of a pseudoscalar, associated to longitudinal photons propagating along a magnetic field B, could transforms a Dirac semimetal into a Weyl semimetal with a pair of Weyl nodes for each point of Dirac. The nodes are separated by a pseudovector electric field induced dynamically along B associated to a chiral effect on the Fermi sur…

This https://arxiv.org/abs/2401.07908 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_hept…

On the phase structure of extra-dimensional gauge theories with fermions
We study the phase structure of five-dimensional Yang-Mills theories coupled to Dirac fermions. In order to tackle their non-perturbative character, we derive the flow equations for the gauge coupling and the effective potential for the Aharonov-Bohm phases employing the Functional Renormalisation Group. We analyse the infrared and ultraviolet fixed-point solutions in the flow of the gauge coupling as a function of the compactification radius of the fifth dimension. We discuss various types of …

Affleck-Dine Dirac Leptogenesis
Neil D. Barrie, Chengcheng Han
https://arxiv.org/abs/2402.15245 https://arxiv.org/pdf/2402.15245

Affleck-Dine Dirac Leptogenesis
We present a minimal framework that realises successful Dirac Leptogenesis through the Affleck-Dine mechanism. A single right-handed neutrino and a neutrinophillic Higgs doublet are introduced to the Standard Model, which couple via a Yukawa interaction. The inflationary setting is induced by a combination of the two Higgs doublets, with their global symmetry violating interactions leading to a net charge generation via the Affleck-Dine mechanism. This simple Standard Model extension exhibits a…

This https://arxiv.org/abs/2403.03518 has been replaced.
initial toot: https://mastoxiv.page/@a…

Tracing Dirac points of topological surface states by ferromagnetic resonance
Ferromagnetic resonance is used to reveal features of the buried electronic band structure at interfaces between ferromagnetic metals and topological insulators. By monitoring the evolution of magnetic damping, the application of this method to a hybrid structure consisting of a ferromagnetic layer and a 3D topological insulator reveals a clear fingerprint of the Dirac point and exhibits additional features of the interfacial band structure not otherwise observable. The underlying spin-pumping …

Calculable neutrino Dirac mass matrix and one-loop $\bar \theta$ in the minimal left-right symmetric model
Gang Li, Ding-Yi Luo, Xiang Zhao
https://arxiv.org/abs/2404.16740

Calculable neutrino Dirac mass matrix and one-loop $\bar θ$ in the minimal left-right symmetric model
We revisit the contribution to the strong CP parameter $\bar θ$ from leptonic CP violation at one-loop level in the minimal left-right symmetric model in the case of parity as the left-right symmetry. The Hermitian neutrino Dirac mass matrix $M_D$ can be calculated using the light and heavy neutrino masses and mixings. We propose a parameterization of the right-handed neutrino mixing matrix $V_R$ and construct the heavy neutrino mass that maintains the Hermiticity of $M_D$. We further apply it…

Spin-dependent edge states in two-dimensional Dirac materials with a flat band
Li-Li Ye, Chen-Di Han, Ying-Cheng Lai
https://arxiv.org/abs/2402.14248 https…

Spin-dependent edge states in two-dimensional Dirac materials with a flat band
The phenomenon of spin-dependent quantum scattering in two-dimensional (2D) pseudospin-1/2 Dirac materials leading to a relativistic quantum chimera was recently uncovered. We investigate spin-dependent Dirac electron optics in 2D pseudospin-1 Dirac materials, where the energy-band structure consists of a pair of Dirac cones and a flat band. In particular, with a suitable combination of external electric fields and a magnetic exchange field, electrons with a specific spin orientation (e.g., spi…

Spin-dependent edge states in two-dimensional Dirac materials with a flat band
Li-Li Ye, Chen-Di Han, Ying-Cheng Lai
https://arxiv.org/abs/2402.14248 https…

Spin-dependent edge states in two-dimensional Dirac materials with a flat band
The phenomenon of spin-dependent quantum scattering in two-dimensional (2D) pseudospin-1/2 Dirac materials leading to a relativistic quantum chimera was recently uncovered. We investigate spin-dependent Dirac electron optics in 2D pseudospin-1 Dirac materials, where the energy-band structure consists of a pair of Dirac cones and a flat band. In particular, with a suitable combination of external electric fields and a magnetic exchange field, electrons with a specific spin orientation (e.g., spi…

This https://arxiv.org/abs/2312.09413 has been replaced.
initial toot: https://mastoxiv.page/@a…

Hofstadter Butterfly and Broken-Symmetry Quantum Hall States in α-Type Organic Dirac Fermion Systems
The electronic state of α-type organic Dirac fermion systems such as α-(ET)_2I_3 or α-(BETS)_2I_3 has been studied under magnetic fields using the four-band tight-binding model with Peierls phase factors. The validity of the Dirac fermion picture in these materials was confirmed by the generated Hofstadter butterfly and its Chern numbers. The four-component envelope function of the N = 0 Landau level with valley degeneracy was studied. It was found that the two degenerate valley states have …