Jorge R. Bolaños-Servín, Roberto Quezada, Josué I. Rios-Cangas
{"title":"Weyl Moments and Quantum Gaussian States","authors":"Jorge R. Bolaños-Servín, Roberto Quezada, Josué I. Rios-Cangas","doi":"10.1016/S0034-4877(22)00081-7","DOIUrl":"10.1016/S0034-4877(22)00081-7","url":null,"abstract":"<div><p>We give a rigorous definition of moments of an unbounded observable with respect to a quantum state<span> in terms of Yosida's approximations of unbounded generators of contractions semigroups. We use this notion to characterize Gaussian states in terms of the moments of the field operator, which we call Weyl moments. As a by-product, rigorous formulae for the mean value vector and the covariance matrix of a Gaussian state are obtained.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 3","pages":"Pages 357-376"},"PeriodicalIF":0.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42540979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Density Operator Formulation for a Supersymmetric Harmonic Oscillator: Vector Coherent State Construction and Statistical Properties","authors":"Isiaka Aremua , Mahouton Norbert Hounkonnou , Komi Sodoga , Paalamwé Komi Tchakpélé","doi":"10.1016/S0034-4877(22)00084-2","DOIUrl":"10.1016/S0034-4877(22)00084-2","url":null,"abstract":"<div><p>Motivated by our recent work published in <span>[23]</span><span><span>, we achieve, in this paper, a matrix formulation of the density operator to construct a two-component vector coherent state representation for a supersymmetric harmonic oscillator. We investigate and discuss the main relevant statistical properties. We use the completeness relation to perform the </span>thermodynamic analysis in the diagonal P-representation of the density operator.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 3","pages":"Pages 399-418"},"PeriodicalIF":0.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44482920","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eduardo Ballico, Elizabeth Gasparim, Thomas Köppe, Bruno Suzuki
{"title":"Poisson Structures on the Conifold and Local Calabi-Yau Threefolds","authors":"Eduardo Ballico, Elizabeth Gasparim, Thomas Köppe, Bruno Suzuki","doi":"10.1016/S0034-4877(22)00078-7","DOIUrl":"10.1016/S0034-4877(22)00078-7","url":null,"abstract":"<div><p>We describe bivector fields and Poisson structures<span> on local Calabi-Yau threefolds which are total spaces of vector bundles on a contractible rational curve. In particular, we calculate all possible holomorphic Poisson structures on the conifold.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 3","pages":"Pages 299-324"},"PeriodicalIF":0.8,"publicationDate":"2022-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43240977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Integration of the sine-Gordon equation with a source and an additional term","authors":"Umid Azadovich Hoitmetov","doi":"10.1016/S0034-4877(22)00067-2","DOIUrl":"10.1016/S0034-4877(22)00067-2","url":null,"abstract":"<div><p>The work is devoted to solving the Cauchy problem for the sine-Gordon equation with an additional term and a self-consistent source in the class of rapidly decreasing functions. The problem is solved by the inverse scattering method. Several special cases of the sine-Gordon equation with an additional term are given, which can be integrated using the inverse scattering method, for example, the loaded sine-Gordon equation. Several examples are given to illustrate the application of the obtained results.</p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 2","pages":"Pages 221-240"},"PeriodicalIF":0.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43556903","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xinyue Li, Zhixin Zhang, Qiulan Zhao , Chuanzhong Li
{"title":"Darboux transformation of two novel two-component generalized complex short pulse equations","authors":"Xinyue Li, Zhixin Zhang, Qiulan Zhao , Chuanzhong Li","doi":"10.1016/S0034-4877(22)00063-5","DOIUrl":"10.1016/S0034-4877(22)00063-5","url":null,"abstract":"<div><p><span>The short pulse equation is able to describe ultra short pulse, which plays a crucial part in the field of </span>optical fiber<span> propagation. In this paper, we investigate a generalized complex short pulse equation and its two-component generalization. We first prove that they are Lax integrable. Subsequently, we obtain their new Lax pairs<span> through hodograph transformation to carry out Darboux transformation, respectively. For the generalized complex short pulse equation, we provide a different Darboux matrix and verify that it is feasible, then we focus on higher-order semi-rational soliton solutions by means of generalized Darboux transformation. For the coupled generalized complex short pulse equations, we apply Darboux transformation to discuss exact solutions by choosing different seed solutions.</span></span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 2","pages":"Pages 157-184"},"PeriodicalIF":0.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46461886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Nonnull soliton surface associated with the Betchov–Da Rios equation","authors":"Yanlin Li, Melek Erdoğdu, Ayşe Yavuz","doi":"10.1016/S0034-4877(22)00068-4","DOIUrl":"10.1016/S0034-4877(22)00068-4","url":null,"abstract":"<div><p><span><span>The aim of this paper is to investigate the nonnull soliton surfaces associated with Betchov–Da Rios equation in Minkowski space-time. The differential geometric properties of these kind of nonnull soliton surfaces are examined with respect to the Lorentzian casual characterizations. Moreover, the linear maps of Weingarten type are obtained which are defined on </span>tangent spaces of these soliton surfaces. Some new results are obtained by means of two geometric invariants </span><em>k</em> and <em>h</em><span> which are generated by linear maps of Weingarten type. Then, the mean curvature vector<span> field and Gaussian curvature of the nonnull soliton surface are obtained. Finally, it is shown that this kind of soliton surface consists of flat points as a numerical example.</span></span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 2","pages":"Pages 241-255"},"PeriodicalIF":0.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47722939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Crossed-product entangled states","authors":"A. Dehghani, A. Akhound, F. Panahyazdan","doi":"10.1016/S0034-4877(22)00069-6","DOIUrl":"10.1016/S0034-4877(22)00069-6","url":null,"abstract":"<div><p>This paper demonstrates a new formalism of producing some entangled states<span><span> attached to a two-particle system. We explain how these entangled states come directly from a new algebraic method through the cross-product of two spin coherent states. They lead to various quantum states with considerable nonclassical properties, and are capable candidates to minimize the entropic uncertainty relation, too. We will also examine and optimize the quantum properties of these states, for example by selecting the appropriate parameters one can </span>control quantum (classical) correlations.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 2","pages":"Pages 257-270"},"PeriodicalIF":0.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48669251","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Lagrangian based thermal conduction","authors":"Ferenc Márkus, András Szegleti","doi":"10.1016/S0034-4877(22)00064-7","DOIUrl":"10.1016/S0034-4877(22)00064-7","url":null,"abstract":"<div><p><span>Based on the Lagrangian description of a dissipative oscillator, the </span>Hamiltonian<span> description and the solution of Fourier heat conduction<span> including the initial and boundary conditions are treated here. It is pointed out that the method can be extended to solve thermal problems. It means that a mathematical tool is elaborated here, that enables us to calculate also the complete solution of thermal propagation involving the Maxwell--Cattaneo--Vernotte (MCV) telegrapher type. In other words, we can solve transport equations described by linear partial differential equations, in general, in which both the initial and the boundary conditions are taken into account. The presented study offers a new kind of numerical solution to certain partial differential equations.</span></span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 2","pages":"Pages 185-191"},"PeriodicalIF":0.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42971317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Sasakian structure on the unit tangent bundle of a Finsler manifold","authors":"Hassan Attarchi","doi":"10.1016/S0034-4877(22)00062-3","DOIUrl":"10.1016/S0034-4877(22)00062-3","url":null,"abstract":"<div><p><span>In this work, we introduce an adopted local frame on the tangent bundle<span> of a Finsler manifold with respect to the natural foliations of the tangent bundle. We show the prominence of using this local frame by studying some geometric properties of the foliations and distributions on the tangent bundle of a Finsler manifold. Moreover, we find the necessary and sufficient conditions on the Finsler manifold (</span></span><strong><em>M, F</em></strong>) such that the unit tangent bundle admits a Sasakian structure.</p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 2","pages":"Pages 147-156"},"PeriodicalIF":0.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46364392","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Wave scattering by many small impedance particles and applications","authors":"Alexander G. Ramm","doi":"10.1016/S0034-4877(22)00065-9","DOIUrl":"10.1016/S0034-4877(22)00065-9","url":null,"abstract":"<div><p>Formulas are derived for solutions of many-body wave scattering problem by small impedance particles embedded in a homogeneous medium. The limiting case is considered, when the size <em>a</em> of small particles tends to zero while their number tends to infinity at a suitable rate. The basic physical assumption is <em>a << d << λ</em>, where <em>d</em> is the minimal distance between neighboring particles, <em>λ</em> is the wavelength, and the particles can be impedance balls <em>B</em>(<em>x<sub>m</sub>, a</em>) with centers <em>x<sub>m</sub></em> located on a grid. Equations for the limiting effective (self-consistent) field in the medium are derived. It is proved that one can create material with a desired refraction coefficient by embedding in a free space many small balls of radius <em>a</em> with prescribed boundary impedances. The small balls can be centered at the points located on a grid. A recipe for creating materials with a desired refraction coefficient is formulated. It is proved that materials with a desired radiation pattern, for example, wave-focusing materials, can be created.</p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"90 2","pages":"Pages 193-202"},"PeriodicalIF":0.8,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47414625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}