Pub Date : 2026-03-12DOI: 10.1007/s13324-026-01170-1
Graeme Reinhart, Brian Simanek
Two interesting phenomena for the construction of quantum states are that of mutually unbiased bases and that of balanced states. We explore a constructive approach to each phenomenon that involves orthogonal polynomials on the unit circle. In the case of mutually unbiased bases, we show that this approach does not produce such bases. In the case of balanced states, we provide examples of pairs of orthonormal bases and states that are balanced with respect to them. We also consider extensions of these ideas to the infinite dimensional setting.
{"title":"Orthogonal Polynomials on the Unit Circle, Mutually Unbiased Bases, and Balanced States","authors":"Graeme Reinhart, Brian Simanek","doi":"10.1007/s13324-026-01170-1","DOIUrl":"10.1007/s13324-026-01170-1","url":null,"abstract":"<div><p>Two interesting phenomena for the construction of quantum states are that of mutually unbiased bases and that of balanced states. We explore a constructive approach to each phenomenon that involves orthogonal polynomials on the unit circle. In the case of mutually unbiased bases, we show that this approach does not produce such bases. In the case of balanced states, we provide examples of pairs of orthonormal bases and states that are balanced with respect to them. We also consider extensions of these ideas to the infinite dimensional setting.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":"16 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13324-026-01170-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147441127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-09DOI: 10.1007/s13324-026-01179-6
Mandeep Singh
In this article, we investigate sharp functional inequalities associated with the coherent state transforms of the Lie group ( SU(N,1) ). Assuming the isoperimetric conjecture on the complex hyperbolic ball, we establish the Lieb–Wehrl entropy conjecture for ( SU(N,1) ) with ( N ge 2 ). Furthermore, we derive an extension of the Faber–Krahn type inequality within the framework of the Bergman space ( mathcal {A}_{alpha } ).
在本文中,我们研究了与李群( SU(N,1) )的相干态变换相关的尖锐泛函不等式。假设复双曲球的等周猜想,我们用( N ge 2 )建立了( SU(N,1) )的Lieb-Wehrl熵猜想。进一步,我们在Bergman空间( mathcal {A}_{alpha } )的框架内导出了Faber-Krahn型不等式的扩展。
{"title":"On the Lieb–Wehrl Entropy conjecture for SU(N, 1)","authors":"Mandeep Singh","doi":"10.1007/s13324-026-01179-6","DOIUrl":"10.1007/s13324-026-01179-6","url":null,"abstract":"<div><p>In this article, we investigate sharp functional inequalities associated with the coherent state transforms of the Lie group <span>( SU(N,1) )</span>. Assuming the isoperimetric conjecture on the complex hyperbolic ball, we establish the Lieb–Wehrl entropy conjecture for <span>( SU(N,1) )</span> with <span>( N ge 2 )</span>. Furthermore, we derive an extension of the Faber–Krahn type inequality within the framework of the Bergman space <span>( mathcal {A}_{alpha } )</span>.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":"16 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147440926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-02DOI: 10.1007/s13324-026-01175-w
Daniele Barbera, Vladimir Georgiev, Mario Rastrelli
The paper studies the existence of solutions for the reaction-diffusion equation in (mathbb {R}^2) with point-interaction laplacian (Delta _alpha ) with (alpha in (-infty ,+infty ]), assuming the functions to remain on the absolute continuous projection space. By semigroup estimates, we get the existence and uniqueness of solutions on
with (r>2), (s<frac{2}{r}) for the Cauchy problem with small (T>0) or small initial conditions on (H^1_alpha (mathbb {R}^2)). Finally, we prove decay in time of the functions.
{"title":"On the Cauchy problem for the reaction-diffusion system with point-interaction in (mathbb {R}^2)","authors":"Daniele Barbera, Vladimir Georgiev, Mario Rastrelli","doi":"10.1007/s13324-026-01175-w","DOIUrl":"10.1007/s13324-026-01175-w","url":null,"abstract":"<div><p>The paper studies the existence of solutions for the reaction-diffusion equation in <span>(mathbb {R}^2)</span> with point-interaction laplacian <span>(Delta _alpha )</span> with <span>(alpha in (-infty ,+infty ])</span>, assuming the functions to remain on the absolute continuous projection space. By semigroup estimates, we get the existence and uniqueness of solutions on </p><div><div><span>$$begin{aligned} L^infty left( (0,T);H^1_alpha left( mathbb {R}^2right) right) cap L^rleft( (0,T);H^{s+1}_alpha left( mathbb {R}^2right) right) , end{aligned}$$</span></div></div><p>with <span>(r>2)</span>, <span>(s<frac{2}{r})</span> for the Cauchy problem with small <span>(T>0)</span> or small initial conditions on <span>(H^1_alpha (mathbb {R}^2))</span>. Finally, we prove decay in time of the functions.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":"16 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13324-026-01175-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147335907","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-02DOI: 10.1007/s13324-026-01177-8
Milutin Obradović, Nikola Tuneski, Paweł Zaprawa
This paper, motivated by the previous one [12], presents some new achievements in estimating Hankel determinants for the class (mathcal {S}) of univalent functions. With the help of the Grunsky inequalities, we improve earlier results for the bound of (H_3(1)) in (mathcal {S}). It is shown that this bound is less than 1. Moreover, we obtain the bounds of (H_3(1)) for univalent functions with the second or the third coefficient vanishing. In particular, the estimate of (H_3(1)) for odd univalent functions is derived.
{"title":"An improved estimate of the third Hankel determinant for univalent functions","authors":"Milutin Obradović, Nikola Tuneski, Paweł Zaprawa","doi":"10.1007/s13324-026-01177-8","DOIUrl":"10.1007/s13324-026-01177-8","url":null,"abstract":"<div><p>This paper, motivated by the previous one [12], presents some new achievements in estimating Hankel determinants for the class <span>(mathcal {S})</span> of univalent functions. With the help of the Grunsky inequalities, we improve earlier results for the bound of <span>(H_3(1))</span> in <span>(mathcal {S})</span>. It is shown that this bound is less than 1. Moreover, we obtain the bounds of <span>(H_3(1))</span> for univalent functions with the second or the third coefficient vanishing. In particular, the estimate of <span>(H_3(1))</span> for odd univalent functions is derived.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":"16 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147336001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-03-02DOI: 10.1007/s13324-025-01160-9
Romulo Diaz Carlos, J. Vanterler da C. Sousa, El-Houari Hamza
In this paper we present a ground state solution result for the nonlocal operator such as the generalized p-Laplacian operator with a logarithmic nonlinearity, for which we will use variational methods explicitly the Nehari method.
{"title":"Ground state solution for the generalized p-Laplacian operator with logarithmic nonlinearity","authors":"Romulo Diaz Carlos, J. Vanterler da C. Sousa, El-Houari Hamza","doi":"10.1007/s13324-025-01160-9","DOIUrl":"10.1007/s13324-025-01160-9","url":null,"abstract":"<div><p>In this paper we present a ground state solution result for the nonlocal operator such as the generalized p-Laplacian operator with a logarithmic nonlinearity, for which we will use variational methods explicitly the Nehari method.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":"16 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s13324-025-01160-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147335999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-26DOI: 10.1007/s13324-026-01173-y
Shankey Kumar, Saminathan Ponnusamy
This article is motivated by the concept of mixed Bohr radius for scalar-valued functions defined in Banach sequence spaces. More precisely, it aims to determine bounds of mixed Bohr radii for holomorphic functions defined on Banach sequence spaces with values in Banach spaces. We determine an upper bound of the mixed Bohr radius by establishing a connection between the mixed Bohr radius and the arithmetic Bohr radius. However, the lower bound is obtained through the implementation of techniques developed recently by Defant, Galicer, Maestre, Mansilla, Muro, and Schwarting.
{"title":"Bounds on mixed Bohr radii of vector-valued holomorphic functions on Banach spaces","authors":"Shankey Kumar, Saminathan Ponnusamy","doi":"10.1007/s13324-026-01173-y","DOIUrl":"10.1007/s13324-026-01173-y","url":null,"abstract":"<div><p>This article is motivated by the concept of mixed Bohr radius for scalar-valued functions defined in Banach sequence spaces. More precisely, it aims to determine bounds of mixed Bohr radii for holomorphic functions defined on Banach sequence spaces with values in Banach spaces. We determine an upper bound of the mixed Bohr radius by establishing a connection between the mixed Bohr radius and the arithmetic Bohr radius. However, the lower bound is obtained through the implementation of techniques developed recently by Defant, Galicer, Maestre, Mansilla, Muro, and Schwarting.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":"16 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147342475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-25DOI: 10.1007/s13324-026-01176-9
Xianguo Geng, Minxin Jia, Jiao Wei
In this paper, we establish the theory of tetragonal curves and present a systematic method for constructing Riemann theta function solutions to algebro-geometric initial value problems for matrix mKdV equations. Starting from a (4times 4) matrix spectral problem, we derive Lax pairs of matrix mKdV equations using the zero-curvature equation and Lenard equations. The corresponding tetragonal curve is introduced via the characteristic polynomial of the Lax matrices of the hierarchy. Then we discuss Riemann theta functions, the construction of the basis of holomorphic differentials, as well as Abelian differentials of the second and third kinds. Based on the theory of tetragonal curves, we analyze algebro-geometric properties of Baker-Akhiezer functions and a class of meromorphic functions. Finally, we obtain Riemann theta function solutions for the whole matrix mKdV hierarchy through asymptotic analysis.
{"title":"Tetragonal curves and Riemann theta function solutions of the matrix mKdV equations","authors":"Xianguo Geng, Minxin Jia, Jiao Wei","doi":"10.1007/s13324-026-01176-9","DOIUrl":"10.1007/s13324-026-01176-9","url":null,"abstract":"<div><p>In this paper, we establish the theory of tetragonal curves and present a systematic method for constructing Riemann theta function solutions to algebro-geometric initial value problems for matrix mKdV equations. Starting from a <span>(4times 4)</span> matrix spectral problem, we derive Lax pairs of matrix mKdV equations using the zero-curvature equation and Lenard equations. The corresponding tetragonal curve is introduced via the characteristic polynomial of the Lax matrices of the hierarchy. Then we discuss Riemann theta functions, the construction of the basis of holomorphic differentials, as well as Abelian differentials of the second and third kinds. Based on the theory of tetragonal curves, we analyze algebro-geometric properties of Baker-Akhiezer functions and a class of meromorphic functions. Finally, we obtain Riemann theta function solutions for the whole matrix mKdV hierarchy through asymptotic analysis.</p></div>","PeriodicalId":48860,"journal":{"name":"Analysis and Mathematical Physics","volume":"16 2","pages":""},"PeriodicalIF":1.6,"publicationDate":"2026-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147342025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"数学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-24DOI: 10.1007/s13324-026-01174-x
Zouheir Amara
Let (mathcal {H}) be a separable complex Hilbert space. A conjugate-linear map (C:mathcal {H}rightarrow mathcal {H}) is called a conjugation if it is an involutive isometry. In this paper, we focus on the following interpolation problems: Let ({x_i}_{iin I}) and ({y_i}_{iin I}) be orthonormal sets of vectors in (mathcal {H}), and let ({N_k}_{kin K}) be a set of mutually commuting normal operators. We seek to determine under which conditions there exists a conjugation C on (mathcal {H}) such that