Pub Date : 2024-03-07DOI: 10.1017/s0013091524000038
Daniel Asimov, Florian Frick, Michael Harrison, Wesley Pegden
We show that if an open set in $mathbb{R}^d$ can be fibered by unit n-spheres, then $d geq 2n+1$, and if $d = 2n+1$, then the spheres must be pairwise linked, and $n in left{0, 1, 3, 7 right}$. For these values of n, we construct unit n-sphere fibrations in $mathbb{R}^{2n+1}$.
我们证明,如果$mathbb{R}^d$中的一个开集可以被单位n球纤维化,那么$d geq 2n+1$,如果$d = 2n+1$,那么球体必须是成对链接的,并且$n in left{0,1,3,7 right}$。对于这些 n 值,我们在 $mathbb{R}^{2n+1}$ 中构造单位 n 球纤维。
{"title":"Unit sphere fibrations in Euclidean space","authors":"Daniel Asimov, Florian Frick, Michael Harrison, Wesley Pegden","doi":"10.1017/s0013091524000038","DOIUrl":"https://doi.org/10.1017/s0013091524000038","url":null,"abstract":"<p>We show that if an open set in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240306133538207-0692:S0013091524000038:S0013091524000038_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$mathbb{R}^d$</span></span></img></span></span> can be fibered by unit <span>n</span>-spheres, then <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240306133538207-0692:S0013091524000038:S0013091524000038_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$d geq 2n+1$</span></span></img></span></span>, and if <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240306133538207-0692:S0013091524000038:S0013091524000038_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$d = 2n+1$</span></span></img></span></span>, then the spheres must be pairwise linked, and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240306133538207-0692:S0013091524000038:S0013091524000038_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$n in left{0, 1, 3, 7 right}$</span></span></img></span></span>. For these values of <span>n</span>, we construct unit <span>n</span>-sphere fibrations in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240306133538207-0692:S0013091524000038:S0013091524000038_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$mathbb{R}^{2n+1}$</span></span></img></span></span>.</p>","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140055024","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 : 2024-03-07DOI: 10.1017/s0013091524000117
Shun Maeta
We consider the broadest concept of the gradient Yamabe soliton, the conformal gradient soliton. In this paper, we elucidate the structure of complete gradient conformal solitons under some assumption, and provide some applications to gradient Yamabe solitons. These results enhance the understanding gained from previous research. Furthermore, we give an affirmative partial answer to the Yamabe soliton version of Perelman’s conjecture.
{"title":"Structure of generalized Yamabe solitons and its applications","authors":"Shun Maeta","doi":"10.1017/s0013091524000117","DOIUrl":"https://doi.org/10.1017/s0013091524000117","url":null,"abstract":"<p>We consider the broadest concept of the gradient Yamabe soliton, the conformal gradient soliton. In this paper, we elucidate the structure of complete gradient conformal solitons under some assumption, and provide some applications to gradient Yamabe solitons. These results enhance the understanding gained from previous research. Furthermore, we give an affirmative partial answer to the Yamabe soliton version of Perelman’s conjecture.</p>","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140055010","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 : 2024-03-07DOI: 10.1017/s0013091524000075
Guo-shuai Mao, Lilong Wang
In this paper, we mainly prove the following conjectures of Sun [16]: Let p > 3 be a prime. Thenbegin{align*}&A_{2p}equiv A_2-frac{1648}3p^3B_{p-3} ({rm{mod}} p^4),&A_{2p-1}equiv A_1+frac{16p^3}3B_{p-3} ({rm{mod}} p^4),&A_{3p}equiv A_3-36738p^3B_{p-3} ({rm{mod}} p^4),end{align*}
where $A_n=sum_{k=0}^nbinom{n}k^2binom{n+k}{k}^2$ is the nth Apéry number, and Bn is the nth Bernoulli number.
本文主要证明 Sun [16] 的下列猜想:设 p > 3 是素数。Thenbegin{align*}&A_{2p}equiv A_2-frac{1648}3p^3B_{p-3} ({rm{mod}} p^4),&A_{2p-1}equiv A_1+frac{16p^3}3B_{p-3} ({rm{mod}} p^4),&;A_{3p}equiv A_3-36738p^3B_{p-3} ({rm{mod} p^4),end{align*}where $A_n=sum_{k=0}^nbinom{n}k^2binom{n+k}{k}^2$ is the nth Apéry number, and Bn is the nth Bernoulli number.
{"title":"Proof of some conjectural congruences involving Apéry and Apéry-like numbers","authors":"Guo-shuai Mao, Lilong Wang","doi":"10.1017/s0013091524000075","DOIUrl":"https://doi.org/10.1017/s0013091524000075","url":null,"abstract":"<p>In this paper, we mainly prove the following conjectures of Sun [16]: Let <span>p</span> > 3 be a prime. Then<span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240306144432913-0876:S0013091524000075:S0013091524000075_eqnU1.png\"><span data-mathjax-type=\"texmath\"><span>begin{align*}&A_{2p}equiv A_2-frac{1648}3p^3B_{p-3} ({rm{mod}} p^4),&A_{2p-1}equiv A_1+frac{16p^3}3B_{p-3} ({rm{mod}} p^4),&A_{3p}equiv A_3-36738p^3B_{p-3} ({rm{mod}} p^4),end{align*}</span></span></img></span></p><p contenttype=\"noindent\">where <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240306144432913-0876:S0013091524000075:S0013091524000075_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$A_n=sum_{k=0}^nbinom{n}k^2binom{n+k}{k}^2$</span></span></img></span></span> is the <span>n</span>th Apéry number, and <span>B<span>n</span></span> is the <span>n</span>th Bernoulli number.</p>","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140055029","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 : 2024-02-12DOI: 10.1017/s0013091524000014
Md Firoz Ali, Sanjit Pal
For $-1leq B lt Aleq 1$, let $mathcal{C}(A,B)$ denote the class of normalized Janowski convex functions defined in the unit disk $mathbb{D}:={zinmathbb{C}:|z| lt 1}$ that satisfy the subordination relation $1+zf''(z)/f'(z)prec (1+Az)/(1+Bz)$. In the present article, we determine the sharp estimate of the Schwarzian norm for functions in the class $mathcal{C}(A,B)$. The Dieudonné’s lemma which gives the exact region of variability for derivatives at a point of bounded functions, plays the key role in this study, and we also use this lemma to construct the extremal functions for the sharpness by a new method.
{"title":"The Schwarzian norm estimates for Janowski convex functions","authors":"Md Firoz Ali, Sanjit Pal","doi":"10.1017/s0013091524000014","DOIUrl":"https://doi.org/10.1017/s0013091524000014","url":null,"abstract":"For <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" xlink:href=\"S0013091524000014_inline1.png\" /> <jats:tex-math>$-1leq B lt Aleq 1$</jats:tex-math> </jats:alternatives> </jats:inline-formula>, let <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" xlink:href=\"S0013091524000014_inline2.png\" /> <jats:tex-math>$mathcal{C}(A,B)$</jats:tex-math> </jats:alternatives> </jats:inline-formula> denote the class of normalized Janowski convex functions defined in the unit disk <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" xlink:href=\"S0013091524000014_inline3.png\" /> <jats:tex-math>$mathbb{D}:={zinmathbb{C}:|z| lt 1}$</jats:tex-math> </jats:alternatives> </jats:inline-formula> that satisfy the subordination relation <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" xlink:href=\"S0013091524000014_inline4.png\" /> <jats:tex-math>$1+zf''(z)/f'(z)prec (1+Az)/(1+Bz)$</jats:tex-math> </jats:alternatives> </jats:inline-formula>. In the present article, we determine the sharp estimate of the Schwarzian norm for functions in the class <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" xlink:href=\"S0013091524000014_inline5.png\" /> <jats:tex-math>$mathcal{C}(A,B)$</jats:tex-math> </jats:alternatives> </jats:inline-formula>. The Dieudonné’s lemma which gives the exact region of variability for derivatives at a point of bounded functions, plays the key role in this study, and we also use this lemma to construct the extremal functions for the sharpness by a new method.","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139773202","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 : 2024-01-12DOI: 10.1017/s0013091523000755
Łukasz Pawelec
We show a new method of estimating the Hausdorff measure of a set from below. The method requires computing the subsequent closest return times of a point to itself.
{"title":"Estimating the Hausdorff measure using recurrence","authors":"Łukasz Pawelec","doi":"10.1017/s0013091523000755","DOIUrl":"https://doi.org/10.1017/s0013091523000755","url":null,"abstract":"We show a new method of estimating the Hausdorff measure of a set from below. The method requires computing the subsequent closest return times of a point to itself.","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139459729","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 : 2024-01-11DOI: 10.1017/s0013091523000809
Arup Chattopadhyay, Soma Das
Consider the multiplication operator MB in $L^2(mathbb{T})$, where the symbol B is a finite Blaschke product. In this article, we characterize the commutant of MB in $L^2(mathbb{T})$. As an application of this characterization result, we explicitly determine the class of conjugations commuting with $M_{z^2}$ or making $M_{z^2}$ complex symmetric by introducing a new class of conjugations in $L^2(mathbb{T})$. Moreover, we analyse their properties while keeping the whole Hardy space, model space and Beurling-type subspaces invariant. Furthermore, we extended our study concerning conjugations in the case of finite Blaschke products.
{"title":"Commutants and complex symmetry of finite Blaschke product multiplication operator in","authors":"Arup Chattopadhyay, Soma Das","doi":"10.1017/s0013091523000809","DOIUrl":"https://doi.org/10.1017/s0013091523000809","url":null,"abstract":"<p>Consider the multiplication operator <span>M<span>B</span></span> in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110124038844-0402:S0013091523000809:S0013091523000809_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$L^2(mathbb{T})$</span></span></img></span></span>, where the symbol <span>B</span> is a finite Blaschke product. In this article, we characterize the commutant of <span>M<span>B</span></span> in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110124038844-0402:S0013091523000809:S0013091523000809_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$L^2(mathbb{T})$</span></span></img></span></span>. As an application of this characterization result, we explicitly determine the class of conjugations commuting with <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110124038844-0402:S0013091523000809:S0013091523000809_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$M_{z^2}$</span></span></img></span></span> or making <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110124038844-0402:S0013091523000809:S0013091523000809_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$M_{z^2}$</span></span></img></span></span> complex symmetric by introducing a new class of conjugations in <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110124038844-0402:S0013091523000809:S0013091523000809_inline6.png\"><span data-mathjax-type=\"texmath\"><span>$L^2(mathbb{T})$</span></span></img></span></span>. Moreover, we analyse their properties while keeping the whole Hardy space, model space and Beurling-type subspaces invariant. Furthermore, we extended our study concerning conjugations in the case of finite Blaschke products.</p>","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139423344","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 : 2024-01-11DOI: 10.1017/s0013091523000780
Prasun Roychowdhury, Michael Ruzhansky, Durvudkhan Suragan
We establish a new improvement of the classical Lp-Hardy inequality on the multidimensional Euclidean space in the supercritical case. Recently, in [14], there has been a new kind of development of the one-dimensional Hardy inequality. Using some radialisation techniques of functions and then exploiting symmetric decreasing rearrangement arguments on the real line, the new multidimensional version of the Hardy inequality is given. Some consequences are also discussed.
{"title":"Multidimensional Frank–Laptev–Weidl improvement of the Hardy inequality","authors":"Prasun Roychowdhury, Michael Ruzhansky, Durvudkhan Suragan","doi":"10.1017/s0013091523000780","DOIUrl":"https://doi.org/10.1017/s0013091523000780","url":null,"abstract":"<p>We establish a new improvement of the classical <span>L<span>p</span></span>-Hardy inequality on the multidimensional Euclidean space in the supercritical case. Recently, in [14], there has been a new kind of development of the one-dimensional Hardy inequality. Using some radialisation techniques of functions and then exploiting symmetric decreasing rearrangement arguments on the real line, the new multidimensional version of the Hardy inequality is given. Some consequences are also discussed.</p>","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139423404","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 : 2024-01-11DOI: 10.1017/s0013091523000767
Mohammad Rouzbehani, Massoud Amini, Mohammad B. Asadi
In this article, we introduce and study the notion of Goldie dimension for C*-algebras. We prove that a C*-algebra A has Goldie dimension n if and only if the dimension of the center of its local multiplier algebra is n. In this case, A has finite-dimensional center and its primitive spectrum is extremally disconnected. If moreover, A is extending, we show that it decomposes into a direct sum of n prime C*-algebras. In particular, every stably finite, exact C*-algebra with Goldie dimension, that has the projection property and a strictly full element, admits a full projection and a non-zero densely defined lower semi-continuous trace. Finally we show that certain C*-algebras with Goldie dimension (not necessarily simple, separable or nuclear) are classifiable by the Elliott invariant.
本文将介绍并研究 C* 代数的戈尔迪维度概念。我们证明,当且仅当一个 C* 代数的局部乘子代数的中心维数为 n 时,A 才具有戈尔迪维数 n。在这种情况下,A 具有有限维中心,其原始谱是极端断开的。此外,如果 A 是扩展的,我们会证明它分解为 n 个质数 C*-代数的直接和。特别是,每一个具有戈尔迪维度的稳定有限精确 C* 代数,如果具有投影性质和严格满元素,都会有一个满投影和一个非零的密集定义的下半连续迹。最后,我们证明某些具有戈尔迪维度的 C* 代数(不一定是简单的、可分离的或核的)是可以通过埃利奥特不变量来分类的。
{"title":"Goldie dimension for C*-algebras","authors":"Mohammad Rouzbehani, Massoud Amini, Mohammad B. Asadi","doi":"10.1017/s0013091523000767","DOIUrl":"https://doi.org/10.1017/s0013091523000767","url":null,"abstract":"<p>In this article, we introduce and study the notion of Goldie dimension for C*-algebras. We prove that a C*-algebra <span>A</span> has Goldie dimension <span>n</span> if and only if the dimension of the center of its local multiplier algebra is <span>n</span>. In this case, <span>A</span> has finite-dimensional center and its primitive spectrum is extremally disconnected. If moreover, A is extending, we show that it decomposes into a direct sum of <span>n</span> prime C*-algebras. In particular, every stably finite, exact C*-algebra with Goldie dimension, that has the projection property and a strictly full element, admits a full projection and a non-zero densely defined lower semi-continuous trace. Finally we show that certain C*-algebras with Goldie dimension (not necessarily simple, separable or nuclear) are classifiable by the Elliott invariant.</p>","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139422630","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 : 2024-01-11DOI: 10.1017/s0013091523000792
M.I. Jimenez, R. Tojeiro
Li, Ma and Wang have provided in [13] a partial classification of the so-called Moebius deformable hypersurfaces, that is, the umbilic-free Euclidean hypersurfaces $fcolon M^nto mathbb{R}^{n+1}$ that admit non-trivial deformations preserving the Moebius metric. For $ngeq 5$, the classification was completed by the authors in [12]. In this article we obtain an infinitesimal version of that classification. Namely, we introduce the notion of an infinitesimal Moebius variation of an umbilic-free immersion $fcolon M^nto mathbb{R}^m$ into Euclidean space as a one-parameter family of immersions $f_tcolon M^nto mathbb{R}^m$, with $tin (-epsilon, epsilon)$ and $f_0=f$, such that the Moebius metrics determined by ft coincide up to the first order. Then we characterize isometric immersions $fcolon M^nto mathbb{R}^m$ of arbitrary codimension that admit a non-trivial infinitesimal Moebius variation among those that admit a non-trivial conformal infinitesimal variation, and use such characterization to classify the u
{"title":"Infinitesimally Moebius bendable hypersurfaces","authors":"M.I. Jimenez, R. Tojeiro","doi":"10.1017/s0013091523000792","DOIUrl":"https://doi.org/10.1017/s0013091523000792","url":null,"abstract":"<p>Li, Ma and Wang have provided in [13] a partial classification of the so-called Moebius deformable hypersurfaces, that is, the umbilic-free Euclidean hypersurfaces <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110125208839-0507:S0013091523000792:S0013091523000792_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$fcolon M^nto mathbb{R}^{n+1}$</span></span></img></span></span> that admit non-trivial deformations preserving the Moebius metric. For <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110125208839-0507:S0013091523000792:S0013091523000792_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$ngeq 5$</span></span></img></span></span>, the classification was completed by the authors in [12]. In this article we obtain an infinitesimal version of that classification. Namely, we introduce the notion of an infinitesimal Moebius variation of an umbilic-free immersion <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110125208839-0507:S0013091523000792:S0013091523000792_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$fcolon M^nto mathbb{R}^m$</span></span></img></span></span> into Euclidean space as a one-parameter family of immersions <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110125208839-0507:S0013091523000792:S0013091523000792_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$f_tcolon M^nto mathbb{R}^m$</span></span></img></span></span>, with <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110125208839-0507:S0013091523000792:S0013091523000792_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$tin (-epsilon, epsilon)$</span></span></img></span></span> and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110125208839-0507:S0013091523000792:S0013091523000792_inline6.png\"><span data-mathjax-type=\"texmath\"><span>$f_0=f$</span></span></img></span></span>, such that the Moebius metrics determined by <span>f<span>t</span></span> coincide up to the first order. Then we characterize isometric immersions <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110125208839-0507:S0013091523000792:S0013091523000792_inline7.png\"><span data-mathjax-type=\"texmath\"><span>$fcolon M^nto mathbb{R}^m$</span></span></img></span></span> of arbitrary codimension that admit a non-trivial infinitesimal Moebius variation among those that admit a non-trivial conformal infinitesimal variation, and use such characterization to classify the u","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139422697","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 : 2024-01-11DOI: 10.1017/s0013091523000779
Marian Nowak, Juliusz Stochmal
Let Σ be a σ-algebra of subsets of a set Ω and $B(Sigma)$ be the Banach space of all bounded Σ-measurable scalar functions on Ω. Let $tau(B(Sigma),ca(Sigma))$ denote the natural Mackey topology on $B(Sigma)$. It is shown that a linear operator T from $B(Sigma)$ to a Banach space E is Bochner representable if and only if T is a nuclear operator between the locally convex space $(B(Sigma),tau(B(Sigma),ca(Sigma)))$ and the Banach space E. We derive a formula for the trace of a Bochner representable operator $T:B({cal B} o)rightarrow B({cal B} o)$ generated by a function $fin L^1({cal B} o, C(Omega))$, where Ω is a compact Hausdorff space.
让 Σ 是一个集合 Ω 的子集的 σ 代数,$B(Sigma)$ 是 Ω 上所有有界 Σ 可测标量函数的巴纳赫空间。让 $tau(B(Sigma),ca(Sigma))$ 表示 $B(Sigma)$ 上的自然麦基拓扑。研究表明,当且仅当 T 是局部凸空间 $(B(Sigma),tau(B(Sigma),ca(Sigma)))$ 和巴拿赫空间 E 之间的核算子时,从 $B(Sigma)$ 到巴拿赫空间 E 的线性算子 T 才是 Bochner 可表示的。我们推导出了由函数 $fin L^1({cal B} o, C(Omega))$ 生成的波赫纳可表示算子 $T:B({cal B} o)rightarrow B({cal B} o)$ 的迹的公式,其中 Ω 是一个紧凑的豪斯多夫空间。
{"title":"On traces of Bochner representable operators on the space of bounded measurable functions","authors":"Marian Nowak, Juliusz Stochmal","doi":"10.1017/s0013091523000779","DOIUrl":"https://doi.org/10.1017/s0013091523000779","url":null,"abstract":"<p>Let Σ be a <span>σ</span>-algebra of subsets of a set Ω and <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110130638066-0304:S0013091523000779:S0013091523000779_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$B(Sigma)$</span></span></img></span></span> be the Banach space of all bounded Σ-measurable scalar functions on Ω. Let <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110130638066-0304:S0013091523000779:S0013091523000779_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$tau(B(Sigma),ca(Sigma))$</span></span></img></span></span> denote the natural Mackey topology on <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110130638066-0304:S0013091523000779:S0013091523000779_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$B(Sigma)$</span></span></img></span></span>. It is shown that a linear operator <span>T</span> from <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110130638066-0304:S0013091523000779:S0013091523000779_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$B(Sigma)$</span></span></img></span></span> to a Banach space <span>E</span> is Bochner representable if and only if <span>T</span> is a nuclear operator between the locally convex space <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110130638066-0304:S0013091523000779:S0013091523000779_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$(B(Sigma),tau(B(Sigma),ca(Sigma)))$</span></span></img></span></span> and the Banach space <span>E</span>. We derive a formula for the trace of a Bochner representable operator <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110130638066-0304:S0013091523000779:S0013091523000779_inline6.png\"><span data-mathjax-type=\"texmath\"><span>$T:B({cal B} o)rightarrow B({cal B} o)$</span></span></img></span></span> generated by a function <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240110130638066-0304:S0013091523000779:S0013091523000779_inline7.png\"><span data-mathjax-type=\"texmath\"><span>$fin L^1({cal B} o, C(Omega))$</span></span></img></span></span>, where Ω is a compact Hausdorff space.</p>","PeriodicalId":20586,"journal":{"name":"Proceedings of the Edinburgh Mathematical Society","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2024-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139422804","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}