{"title":"On the discrete modified KP hierarchies: The Wronskian solutions for their constrained cases","authors":"Ge Yi, Liyun Wang, Kelei Tian, Ying Xu","doi":"10.1016/S0034-4877(23)00057-5","DOIUrl":"10.1016/S0034-4877(23)00057-5","url":null,"abstract":"<div><p>The discrete modified KP hierarchies are compatible with generalized <em>k</em><span>-constraints. By means of the gauge transformation, a large class of solutions can be represented by the Wronskian<span> determinants of functions satisfying a set of linear equations<span>. In this paper, we give a sufficient and necessary condition to reduce the discrete mKP hierarchies obtained by the Wronskian solutions to the discrete </span></span></span><em>k</em>-constrained mKP hierarchies.</p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"92 1","pages":"Pages 85-97"},"PeriodicalIF":0.8,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44999197","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":"Exponential entropy on sequential effect algebras","authors":"Akhilesh Kumar Singh","doi":"10.1016/S0034-4877(23)00054-X","DOIUrl":"10.1016/S0034-4877(23)00054-X","url":null,"abstract":"<div><p>The present paper introduces a new definition of entropy on sequential effect algebras. Unlike the logarithmic behaviour of the entropy defined in the literature, the entropy considered here is of exponential nature. Conditional entropy<span> and entropy on the dynamical system are also introduced and studied. It is also proved that entropy of the dynamical system is invariant under isomorphism.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"92 1","pages":"Pages 49-58"},"PeriodicalIF":0.8,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49341459","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":"The construction of Gel'fand triplet space structure for Infinite Potential Well System","authors":"Onur Genç, Haydar Uncu","doi":"10.1016/S0034-4877(23)00036-8","DOIUrl":"10.1016/S0034-4877(23)00036-8","url":null,"abstract":"<div><p><span>The Hilbert space is the space which is usually chosen as the space of state vectors. In addition, the operators of </span>quantum mechanics<span> act on that space. However, the Hilbert space cannot provide a proper mathematical structure to define Dirac formulation. In particular, the use of Dirac formalism on the domain of definition of an observable leads to some physical contradictions. One example arises from the Infinite Potential Well System (IPWS) which is one of the most fundamental systems of quantum mechanics. Our aim in this paper is the explicit construction of the Gel'fand triplet for the IPWS.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"91 3","pages":"Pages 291-300"},"PeriodicalIF":0.8,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46414940","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}
S. Bukbech , K. El Anouz , Z. El Allali , A. El Allati
{"title":"Quantum-like correlation of two-qubit open system in the Markovian regime","authors":"S. Bukbech , K. El Anouz , Z. El Allali , A. El Allati","doi":"10.1016/S0034-4877(23)00038-1","DOIUrl":"10.1016/S0034-4877(23)00038-1","url":null,"abstract":"<div><p>A rigorous relationship between local quantum uncertainty and local quantum Fisher information<span><span><span> as recent quantifiers of nonclassical correlations is investigated. It consists of analysing the quantum correlation<span> rate ingrained in a bipartite quantum system interacting with its surrounding environment under the Markovian regime. Indeed, we quantify the separability between two </span></span>qubits where each qubit interacts with its own environment. Furthermore, a common reservoir is also taken into consideration, which allows us to solve exactly the Markovian master equation of this system. Pointing out that the degrees of freedom that belong to the environment, act only implicitly. We study the local quantum uncertainty and local quantum Fisher information quantifiers of the open system. By controlling several parameters encoded in the </span>reduced density operator of the open system, it is shown that the nonclassical measures fluctuate similarly between their maximum and minimum amplitudes. In particular, the high values of the damping rates related to each reservoir and some special values of the initial phase parameter allow for robust values of local quantum uncertainty and local quantum Fisher information. In particular, it is shown that in the non-resonance case, it is possible to enhance the quantum correlation of the proposed system.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"91 3","pages":"Pages 315-344"},"PeriodicalIF":0.8,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43208690","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":"Calculation of the electromagnetic self-force of a non-lorentz-contractible uniformly charged spherical shell in arbitrary rectilinear motion","authors":"G. Vaman","doi":"10.1016/S0034-4877(23)00042-3","DOIUrl":"10.1016/S0034-4877(23)00042-3","url":null,"abstract":"<div><p><span><span>We write the electromagnetic self-force of a non-Lorentz-contractible uniformly charged shell of radius a as a series in powers of a, and we calculate the first three terms of this expansion. The method of calculation presented here allows the exact consideration of all linear and </span>nonlinear terms in velocity and its derivatives corresponding to a given power of </span><em>a.</em> Our calculation is entirely done in the laboratory frame of reference.</p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"91 3","pages":"Pages 395-408"},"PeriodicalIF":0.8,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41388880","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":"Galois symmetry of energy levels of the XXX model for the case of octagonal two-magnon states on the generic star of quasimomentum","authors":"T. Lulek, M. Łabuz, J. Milewski, R. Stagraczyński","doi":"10.1016/S0034-4877(23)00039-3","DOIUrl":"10.1016/S0034-4877(23)00039-3","url":null,"abstract":"<div><p>We consider the factor <em>υ</em><span> of the characteristic polynomial </span><em>w<sup>H</sup></em> (<em>x</em><span>) of the Heisenberg Hamiltonian </span><em>Ĥ</em> of the XXX model, corresponding to the generic star [<em>k</em> = ±1, ±3] of quasimomentum <em>k</em> for octagonal (<em>N</em><span><span><span> = 8) magnetic ring in the two-magnon sector. This factor is recognized as the fourth-degree polynomial with integer coefficients, indecomposable over the prime number field ℚ of rationals. We demonstrate the physical meaning of the corresponding </span>Galois group<span><span> as the group of permutations of eigenenergies between the quasimomenta entering the generic star of the </span>Brillouin zone of octagon. In particular, we point out the role of intersection of this group with Galois group of the cyclotomic field, responsible for the translational symmetry of octagon. Bound and scattered two-magnon </span></span>eigenstates are identified by their spectra. Some general remarks are made on Galois symmetries within the XXX integrable model.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"91 3","pages":"Pages 345-357"},"PeriodicalIF":0.8,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41469074","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":"Investigation on gradient solitons in perfect fluid spacetimes","authors":"Krishnendu De, Uday Chand De","doi":"10.1016/S0034-4877(23)00035-6","DOIUrl":"10.1016/S0034-4877(23)00035-6","url":null,"abstract":"<div><p><span><span>This article concerns the study of perfect fluid spacetimes equipped with different types of gradient solitons. It is shown that if a perfect fluid spacetime with Killing </span>velocity vector admits a τ-Einstein soliton of gradient type, then the spacetime represents phantom regime, or </span><em>ψ</em><span><span> remains invariant under the velocity vector field ρ. Besides, we establish that in a perfect fluid spacetime with constant scalar curvature<span>, if the Lorentzian metric is the gradient τ-Einstein soliton, then either the τ-Einstein gradient potential function is pointwise<span> collinear with ρ, or the spacetime represents stiff matter fluid. Furthermore, we prove that under certain conditions, a perfect fluid spacetime turns into a generalized Robertson–Walker spacetime, as well as a </span></span></span>static spacetime and such a spacetime is of Petrov type I, D or O. We also characterize perfect fluid spacetimes whose Lorentzian metric is equipped with gradient </span><em>m</em><span>-quasi Einstein solitons and that the perfect fluid spacetime has vanishing expansion scalar, or it represents dark energy era under certain restriction on the potential function.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"91 3","pages":"Pages 277-289"},"PeriodicalIF":0.8,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46430467","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":"Time of arrival operator in the momentum space","authors":"A.M. Schlichtinger, A. Jadczyk","doi":"10.1016/S0034-4877(23)00037-X","DOIUrl":"10.1016/S0034-4877(23)00037-X","url":null,"abstract":"<div><p><span>It is shown that in presence of certain external fields a well-defined self-adjoint time operator exists, satisfying the standard canonical commutation relations with the </span>Hamiltonian<span>. Examples include uniform electric and gravitational fields with nonrelativistic and relativistic Hamiltonians. The physical intepretation of these operators is proposed in terms of time of arrival in the momentum space.</span></p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"91 3","pages":"Pages 301-313"},"PeriodicalIF":0.8,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48726352","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}
Farrukh Mukhamedov , Muzaffar M. Rahmatullaev, Dilshodbek O. EgAMOV
{"title":"Periodic ground states for the mixed spin ising model with competing interactions on a Cayley tree","authors":"Farrukh Mukhamedov , Muzaffar M. Rahmatullaev, Dilshodbek O. EgAMOV","doi":"10.1016/S0034-4877(23)00041-1","DOIUrl":"10.1016/S0034-4877(23)00041-1","url":null,"abstract":"<div><p>In the present paper, translation-invariant and periodic ground states are described for a mixed spin Ising model with competing interactions on the Cayley tree of order two. The limiting behaviour of various Gibbs measures of our mixed spin Ising model is discussed as well.</p></div>","PeriodicalId":49630,"journal":{"name":"Reports on Mathematical Physics","volume":"91 3","pages":"Pages 379-393"},"PeriodicalIF":0.8,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48864948","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}