Pub Date : 2024-09-19DOI: 10.1017/s0305004124000148
COLIN ADAMS, ZACHARY ROMRELL, ALEXANDRA BONAT, MAYA CHANDE, JOYE CHEN, MAXWELL JIANG, DANIEL SANTIAGO, BENJAMIN SHAPIRO, DORA WOODRUFF
In 2010, Turaev introduced knotoids as a variation on knots that replaces the embedding of a circle with the embedding of a closed interval with two endpoints which here we call poles. We define generalised knotoids to allow arbitrarily many poles, intervals and circles, each pole corresponding to any number of interval endpoints, including zero. This theory subsumes a variety of other related topological objects and introduces some particularly interesting new cases. We explore various analogs of knotoid invariants, including height, index polynomials, bracket polynomials and hyperbolicity. We further generalise to knotoidal graphs, which are a natural extension of spatial graphs that allow both poles and vertices.
{"title":"Generalised knotoids","authors":"COLIN ADAMS, ZACHARY ROMRELL, ALEXANDRA BONAT, MAYA CHANDE, JOYE CHEN, MAXWELL JIANG, DANIEL SANTIAGO, BENJAMIN SHAPIRO, DORA WOODRUFF","doi":"10.1017/s0305004124000148","DOIUrl":"https://doi.org/10.1017/s0305004124000148","url":null,"abstract":"<p>In 2010, Turaev introduced knotoids as a variation on knots that replaces the embedding of a circle with the embedding of a closed interval with two endpoints which here we call poles. We define generalised knotoids to allow arbitrarily many poles, intervals and circles, each pole corresponding to any number of interval endpoints, including zero. This theory subsumes a variety of other related topological objects and introduces some particularly interesting new cases. We explore various analogs of knotoid invariants, including height, index polynomials, bracket polynomials and hyperbolicity. We further generalise to knotoidal graphs, which are a natural extension of spatial graphs that allow both poles and vertices.</p>","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"15 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249537","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 : 2024-09-19DOI: 10.1017/s0305004124000185
DAVID CONLON, JOONKYUNG LEE
We say that a graph H dominates another graph H′ if the number of homomorphisms from H′ to any graph G is dominated, in an appropriate sense, by the number of homomorphisms from H to G. We study the family of dominating graphs, those graphs with the property that they dominate all of their subgraphs. It has long been known that even-length paths are dominating in this sense and a result of Hatami implies that all weakly norming graphs are dominating. In a previous paper, we showed that every finite reflection group gives rise to a family of weakly norming, and hence dominating, graphs. Here we revisit this connection to show that there is a much broader class of dominating graphs.
如果从 H′ 到任何图 G 的同构数在适当意义上被从 H 到 G 的同构数所支配,我们就说一个图 H 支配另一个图 H′。众所周知,偶数长度的路径在这个意义上具有支配性,而 Hatami 的一个结果意味着所有弱规范图都具有支配性。在之前的一篇论文中,我们证明了每个有限反射群都会产生一个弱规范图族,因此也是支配图族。在此,我们将重新探讨这一联系,以证明存在一类更广泛的支配图。
{"title":"Domination inequalities and dominating graphs","authors":"DAVID CONLON, JOONKYUNG LEE","doi":"10.1017/s0305004124000185","DOIUrl":"https://doi.org/10.1017/s0305004124000185","url":null,"abstract":"We say that a graph <jats:italic>H</jats:italic> dominates another graph <jats:italic>H</jats:italic><jats:sup>′</jats:sup> if the number of homomorphisms from <jats:italic>H</jats:italic><jats:sup>′</jats:sup> to any graph <jats:italic>G</jats:italic> is dominated, in an appropriate sense, by the number of homomorphisms from <jats:italic>H</jats:italic> to <jats:italic>G</jats:italic>. We study the family of dominating graphs, those graphs with the property that they dominate all of their subgraphs. It has long been known that even-length paths are dominating in this sense and a result of Hatami implies that all weakly norming graphs are dominating. In a previous paper, we showed that every finite reflection group gives rise to a family of weakly norming, and hence dominating, graphs. Here we revisit this connection to show that there is a much broader class of dominating graphs.","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"3 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249544","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 : 2024-09-19DOI: 10.1017/s0305004124000173
ATTILA BÉRCZES, YANN BUGEAUD, KÁLMÁN GYŐRY, JORGE MELLO, ALINA OSTAFE, MIN SHA
In this paper, we establish some finiteness results about the multiplicative dependence of rational values modulo sets which are ‘close’ (with respect to the Weil height) to division groups of finitely generated multiplicative groups of a number field K. For example, we show that under some conditions on rational functions $f_1, ldots, f_nin K(X)$, there are only finitely many elements $alpha in K$ such that $f_1(alpha),ldots,f_n(alpha)$ are multiplicatively dependent modulo such sets.
{"title":"Multiplicative dependence of rational values modulo approximate finitely generated groups","authors":"ATTILA BÉRCZES, YANN BUGEAUD, KÁLMÁN GYŐRY, JORGE MELLO, ALINA OSTAFE, MIN SHA","doi":"10.1017/s0305004124000173","DOIUrl":"https://doi.org/10.1017/s0305004124000173","url":null,"abstract":"<p>In this paper, we establish some finiteness results about the multiplicative dependence of rational values modulo sets which are ‘close’ (with respect to the Weil height) to division groups of finitely generated multiplicative groups of a number field <span>K</span>. For example, we show that under some conditions on rational functions <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918084446080-0836:S0305004124000173:S0305004124000173_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$f_1, ldots, f_nin K(X)$</span></span></img></span></span>, there are only finitely many elements <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918084446080-0836:S0305004124000173:S0305004124000173_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$alpha in K$</span></span></img></span></span> such that <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918084446080-0836:S0305004124000173:S0305004124000173_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$f_1(alpha),ldots,f_n(alpha)$</span></span></img></span></span> are multiplicatively dependent modulo such sets.</p>","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"10 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249538","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 : 2024-09-19DOI: 10.1017/s0305004124000197
ROSS PATERSON
<p>We show that if <span>F</span> is <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline1.png"><span data-mathjax-type="texmath"><span>$mathbb{Q}$</span></span></img></span></span> or a multiquadratic number field, <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline2.png"><span data-mathjax-type="texmath"><span>$pinleft{{2,3,5}right}$</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:20240918140027897-0543:S0305004124000197:S0305004124000197_inline3.png"><span data-mathjax-type="texmath"><span>$K/F$</span></span></img></span></span> is a Galois extension of degree a power of <span>p</span>, then for elliptic curves <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline4.png"><span data-mathjax-type="texmath"><span>$E/mathbb{Q}$</span></span></img></span></span> ordered by height, the average dimension of the <span>p</span>-Selmer groups of <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline5.png"><span data-mathjax-type="texmath"><span>$E/K$</span></span></img></span></span> is bounded. In particular, this provides a bound for the average <span>K</span>-rank of elliptic curves <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline6.png"><span data-mathjax-type="texmath"><span>$E/mathbb{Q}$</span></span></img></span></span> for such <span>K</span>. Additionally, we give bounds for certain representation–theoretic invariants of Mordell–Weil groups over Galois extensions of such <span>F</span>.</p><p>The central result is that: for each finite Galois extension <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline7.png"><span data-mathjax-type="texmath"><span>$K/F$</span></span></img></span></span> of number fields and prime number <span>p</span>, as <span><span><img data-mimesubtype="png" data-type="" src="https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline8.png"/><span data-mathjax-type="texmath"><span>$E/mathbb{Q}$</span></span></span></span> varies, the difference in dimension betwe
我们证明,如果 F 是 $mathbb{Q}$ 或一个多二次数域,$pinleft{2,3,5}right}$ 并且 $K/F$ 是 p 的幂级数的伽罗瓦扩展,那么对于按高度排序的椭圆曲线 $E/mathbb{Q}$,$E/K$ 的 p-Selmer 群的平均维度是有界的。此外,我们还给出了这种 F 的伽罗瓦扩展上的莫德尔-韦尔群的某些表示论不变式的边界。核心结果是:对于数域和素数 p 的每个有限伽罗瓦扩展 $K/F$,随着 $E/mathbb{Q}$ 的变化,$E/K$ 的 p 塞尔默群和 $E/F$ 的 p 塞尔默群的伽罗瓦固定空间维数之差具有有界平均数。
{"title":"The Failure of Galois Descent for p-Selmer Groups of Elliptic Curves","authors":"ROSS PATERSON","doi":"10.1017/s0305004124000197","DOIUrl":"https://doi.org/10.1017/s0305004124000197","url":null,"abstract":"<p>We show that if <span>F</span> is <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline1.png\"><span data-mathjax-type=\"texmath\"><span>$mathbb{Q}$</span></span></img></span></span> or a multiquadratic number field, <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline2.png\"><span data-mathjax-type=\"texmath\"><span>$pinleft{{2,3,5}right}$</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:20240918140027897-0543:S0305004124000197:S0305004124000197_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$K/F$</span></span></img></span></span> is a Galois extension of degree a power of <span>p</span>, then for elliptic curves <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$E/mathbb{Q}$</span></span></img></span></span> ordered by height, the average dimension of the <span>p</span>-Selmer groups of <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$E/K$</span></span></img></span></span> is bounded. In particular, this provides a bound for the average <span>K</span>-rank of elliptic curves <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline6.png\"><span data-mathjax-type=\"texmath\"><span>$E/mathbb{Q}$</span></span></img></span></span> for such <span>K</span>. Additionally, we give bounds for certain representation–theoretic invariants of Mordell–Weil groups over Galois extensions of such <span>F</span>.</p><p>The central result is that: for each finite Galois extension <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline7.png\"><span data-mathjax-type=\"texmath\"><span>$K/F$</span></span></img></span></span> of number fields and prime number <span>p</span>, as <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240918140027897-0543:S0305004124000197:S0305004124000197_inline8.png\"/><span data-mathjax-type=\"texmath\"><span>$E/mathbb{Q}$</span></span></span></span> varies, the difference in dimension betwe","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249536","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 : 2024-09-19DOI: 10.1017/s0305004124000161
THOMAS BLOMME
This paper is the first part in a series of three papers devoted to the study of enumerative invariants of abelian surfaces through the tropical approach. In this paper, we consider the enumeration of genus g curves of fixed degree passing through g points. We compute the tropical multiplicity provided by a correspondence theorem due to T. Nishinou and show that it is possible to refine this multiplicity in the style of the Block–Göttsche refined multiplicity to get tropical refined invariants.
本文是通过热带方法研究无性曲面枚举不变式的系列论文的第一部分。在本文中,我们考虑枚举通过 g 个点的固定阶数的 g 属曲线。我们计算了由 T. Nishinou 提出的对应定理所提供的热带多重性,并证明可以按照 Block-Göttsche 精炼多重性的方式对这一多重性进行精炼,从而得到热带精炼不变式。
{"title":"Tropical curves in abelian surfaces I: enumeration of curves passing through points","authors":"THOMAS BLOMME","doi":"10.1017/s0305004124000161","DOIUrl":"https://doi.org/10.1017/s0305004124000161","url":null,"abstract":"<p>This paper is the first part in a series of three papers devoted to the study of enumerative invariants of abelian surfaces through the tropical approach. In this paper, we consider the enumeration of genus <span>g</span> curves of fixed degree passing through <span>g</span> points. We compute the tropical multiplicity provided by a correspondence theorem due to T. Nishinou and show that it is possible to refine this multiplicity in the style of the Block–Göttsche refined multiplicity to get tropical refined invariants.</p>","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"2 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142249539","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 : 2024-07-12DOI: 10.1017/s0305004124000100
SHOUHEI MA
We give a vanishing and classification result for holomorphic differential forms on smooth projective models of the moduli spaces of pointed K3 surfaces. We prove that there is no nonzero holomorphic k-form for $0<k<10$ and for even $k>19$ . In the remaining cases, we give an isomorphism between the space of holomorphic k-forms with that of vector-valued modular forms ( $10leq k leq 18$ ) or scalar-valued cusp forms (odd $kgeq 19$ ) for the modular group. These results are in fact proved in the generality of lattice-polarisation.
我们给出了尖 K3 曲面模空间光滑投影模型上的全形微分形式的消失和分类结果。我们证明,在 $0<k<10$ 和偶数 $k>19$ 时,不存在非零的全形 k 形式。在其余情况下,我们给出了全形 k 形式空间与模数群的矢量值模数形式($10leq k leq 18$)或标量值尖顶形式(奇$kgeq 19$)空间之间的同构关系。这些结果实际上是在格极化的一般性中证明的。
{"title":"Differential forms on universal K3 surfaces","authors":"SHOUHEI MA","doi":"10.1017/s0305004124000100","DOIUrl":"https://doi.org/10.1017/s0305004124000100","url":null,"abstract":"We give a vanishing and classification result for holomorphic differential forms on smooth projective models of the moduli spaces of pointed <jats:italic>K</jats:italic>3 surfaces. We prove that there is no nonzero holomorphic <jats:italic>k</jats:italic>-form for <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000100_inline1.png\"/> <jats:tex-math> $0<k<10$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> and for even <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000100_inline2.png\"/> <jats:tex-math> $k>19$ </jats:tex-math> </jats:alternatives> </jats:inline-formula>. In the remaining cases, we give an isomorphism between the space of holomorphic <jats:italic>k</jats:italic>-forms with that of vector-valued modular forms (<jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000100_inline3.png\"/> <jats:tex-math> $10leq k leq 18$ </jats:tex-math> </jats:alternatives> </jats:inline-formula>) or scalar-valued cusp forms (odd <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000100_inline4.png\"/> <jats:tex-math> $kgeq 19$ </jats:tex-math> </jats:alternatives> </jats:inline-formula>) for the modular group. These results are in fact proved in the generality of lattice-polarisation.","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"7 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141611481","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 : 2024-05-10DOI: 10.1017/s0305004124000112
OLIVER ROCHE–NEWTON
In this paper, we prove that the bound <jats:disp-formula> <jats:alternatives> <jats:graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" mimetype="image" position="float" xlink:href="S0305004124000112_eqnU1.png"/> <jats:tex-math> begin{equation*}max { |8A-7A|,|5f(A)-4f(A)| } gg |A|^{frac{3}{2} + frac{1}{54}}end{equation*} </jats:tex-math> </jats:alternatives> </jats:disp-formula>holds for all <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" xlink:href="S0305004124000112_inline6.png"/> <jats:tex-math> $A subset mathbb R$ </jats:tex-math> </jats:alternatives> </jats:inline-formula>, and for all convex functions <jats:italic>f</jats:italic> which satisfy an additional technical condition. This technical condition is satisfied by the logarithmic function, and this fact can be used to deduce a sum-product estimate <jats:disp-formula> <jats:alternatives> <jats:graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" mimetype="image" position="float" xlink:href="S0305004124000112_eqnU2.png"/> <jats:tex-math> begin{equation*}max { |16A|, |A^{(16)}| } gg |A|^{frac{3}{2} + c},end{equation*} </jats:tex-math> </jats:alternatives> </jats:disp-formula>for some <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" xlink:href="S0305004124000112_inline7.png"/> <jats:tex-math> $cgt 0$ </jats:tex-math> </jats:alternatives> </jats:inline-formula>. Previously, no sum-product estimate over <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" xlink:href="S0305004124000112_inline8.png"/> <jats:tex-math> $mathbb R$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> with exponent strictly greater than <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" xlink:href="S0305004124000112_inline9.png"/> <jats:tex-math> $3/2$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> was known for any number of variables. Moreover, the technical condition on <jats:italic>f</jats:italic> seems to be satisfied for most interesting cases, and we give some further applications. In particular, we show that <jats:disp-formula> <jats:alternatives> <jats:graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" mimetype="image" position="float" xlink:href="S0305004124000112_eqnU3.png"/> <jats:tex-math> begin{equation*}|AA| leq K|A| implies ,forall d in mathbb R setminus {0 }, ,, |{(a,b) in A times A : a-b=d }| ll K^C |A|^{frac{2}{3}-c^{prime}},end{equation*} </jats:tex-math> </jats:alternatives> </jats:disp-formula>where <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" xlink:href="S0305004124000112_inline10.png"/> <jats:tex-math> $c,C gt 0$ </jats:tex-math> </jats:alternat
在本文中,我们证明了束缚(begin{equation*}max { |8A-7A|,|5f(A)-4f(A)| }|gg |A|^{frac{3}{2}+ frac{1}{54}}end{equation*} 对于所有 $A subset mathbb R$ 以及所有满足附加技术条件的凸函数 f 都成立。对数函数满足这个技术条件,这个事实可以用来推导出一个和积估计值。|A|^{frac{3}{2}.+ c},end{equation*} for some $cgt 0$ .在此之前,对于任意数量的变量,都不知道在 $mathbb R$ 上有指数严格大于 3/2$ 的和积估计。此外,关于 f 的技术条件似乎在大多数有趣的情况下都能满足,我们给出了一些进一步的应用。特别是,我们证明了begin{equation*}|AA|leq K|A| implies ,forall d in mathbb R setminus {0 },,,||{(a,b)in A times A :a-b=d }| |ll K^C |A|^{frac{2}{3}-c^{prime}},end{equation*} 其中 $c,C gt 0$ 是绝对常数。
{"title":"A better than exponent for iterated sums and products over","authors":"OLIVER ROCHE–NEWTON","doi":"10.1017/s0305004124000112","DOIUrl":"https://doi.org/10.1017/s0305004124000112","url":null,"abstract":"In this paper, we prove that the bound <jats:disp-formula> <jats:alternatives> <jats:graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" position=\"float\" xlink:href=\"S0305004124000112_eqnU1.png\"/> <jats:tex-math> begin{equation*}max { |8A-7A|,|5f(A)-4f(A)| } gg |A|^{frac{3}{2} + frac{1}{54}}end{equation*} </jats:tex-math> </jats:alternatives> </jats:disp-formula>holds for all <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000112_inline6.png\"/> <jats:tex-math> $A subset mathbb R$ </jats:tex-math> </jats:alternatives> </jats:inline-formula>, and for all convex functions <jats:italic>f</jats:italic> which satisfy an additional technical condition. This technical condition is satisfied by the logarithmic function, and this fact can be used to deduce a sum-product estimate <jats:disp-formula> <jats:alternatives> <jats:graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" position=\"float\" xlink:href=\"S0305004124000112_eqnU2.png\"/> <jats:tex-math> begin{equation*}max { |16A|, |A^{(16)}| } gg |A|^{frac{3}{2} + c},end{equation*} </jats:tex-math> </jats:alternatives> </jats:disp-formula>for some <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000112_inline7.png\"/> <jats:tex-math> $cgt 0$ </jats:tex-math> </jats:alternatives> </jats:inline-formula>. Previously, no sum-product estimate over <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000112_inline8.png\"/> <jats:tex-math> $mathbb R$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> with exponent strictly greater than <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000112_inline9.png\"/> <jats:tex-math> $3/2$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> was known for any number of variables. Moreover, the technical condition on <jats:italic>f</jats:italic> seems to be satisfied for most interesting cases, and we give some further applications. In particular, we show that <jats:disp-formula> <jats:alternatives> <jats:graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" mimetype=\"image\" position=\"float\" xlink:href=\"S0305004124000112_eqnU3.png\"/> <jats:tex-math> begin{equation*}|AA| leq K|A| implies ,forall d in mathbb R setminus {0 }, ,, |{(a,b) in A times A : a-b=d }| ll K^C |A|^{frac{2}{3}-c^{prime}},end{equation*} </jats:tex-math> </jats:alternatives> </jats:disp-formula>where <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000112_inline10.png\"/> <jats:tex-math> $c,C gt 0$ </jats:tex-math> </jats:alternat","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"18 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140941699","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 : 2024-05-09DOI: 10.1017/s0305004124000124
LUCAS GERIN
We obtain the asymptotic behaviour of the longest increasing/non-decreasing subsequences in a random uniform multiset permutation in which each element in ${1,dots,n}$ occurs k times, where k may depend on n. This generalises the famous Ulam–Hammersley problem of the case $k=1$ . The proof relies on poissonisation and on a careful non-asymptotic analysis of variants of the Hammersley–Aldous–Diaconis particle system.
我们得到了随机均匀多集排列中最长递增/非递减子序列的渐近行为,其中 ${1,dots,n}$ 中的每个元素都出现了 k 次,其中 k 可能取决于 n。证明依赖于泊松化和对哈默斯利-阿尔都斯-迪亚科尼斯粒子系统变体的仔细非渐进分析。
{"title":"The Ulam–Hammersley problem for multiset permutations","authors":"LUCAS GERIN","doi":"10.1017/s0305004124000124","DOIUrl":"https://doi.org/10.1017/s0305004124000124","url":null,"abstract":"We obtain the asymptotic behaviour of the longest increasing/non-decreasing subsequences in a random uniform multiset permutation in which each element in <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000124_inline1.png\"/> <jats:tex-math> ${1,dots,n}$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> occurs <jats:italic>k</jats:italic> times, where <jats:italic>k</jats:italic> may depend on <jats:italic>n</jats:italic>. This generalises the famous Ulam–Hammersley problem of the case <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink=\"http://www.w3.org/1999/xlink\" mime-subtype=\"png\" xlink:href=\"S0305004124000124_inline2.png\"/> <jats:tex-math> $k=1$ </jats:tex-math> </jats:alternatives> </jats:inline-formula>. The proof relies on poissonisation and on a careful non-asymptotic analysis of variants of the Hammersley–Aldous–Diaconis particle system.","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"186 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933401","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 : 2024-05-08DOI: 10.1017/s0305004124000136
ANTTI KÄENMÄKI, PETTERI NISSINEN
We compare the dimension of a non-invertible self-affine set to the dimension of the respective invertible self-affine set. In particular, for generic planar self-affine sets, we show that the dimensions coincide when they are large and differ when they are small. Our study relies on thermodynamic formalism where, for dominated and irreducible matrices, we completely characterise the behaviour of the pressures.
{"title":"Non-invertible planar self-affine sets","authors":"ANTTI KÄENMÄKI, PETTERI NISSINEN","doi":"10.1017/s0305004124000136","DOIUrl":"https://doi.org/10.1017/s0305004124000136","url":null,"abstract":"We compare the dimension of a non-invertible self-affine set to the dimension of the respective invertible self-affine set. In particular, for generic planar self-affine sets, we show that the dimensions coincide when they are large and differ when they are small. Our study relies on thermodynamic formalism where, for dominated and irreducible matrices, we completely characterise the behaviour of the pressures.","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"109 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140933417","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 : 2024-03-26DOI: 10.1017/s0305004124000070
CARMEN GALAZ GARCÍA
For odd n we construct a path $rho;:;thinspace Pi_1(S) to SL(nmathbb{R})$ of discrete, faithful, and Zariski dense representations of a surface group such that $rho_t(Pi_1(S)) subset SL(n,mathbb{Q})$ for every $tin mathbb{Q}$.
{"title":"Zariski dense surface subgroups in","authors":"CARMEN GALAZ GARCÍA","doi":"10.1017/s0305004124000070","DOIUrl":"https://doi.org/10.1017/s0305004124000070","url":null,"abstract":"<p>For odd <span>n</span> we construct a path <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240325160819198-0562:S0305004124000070:S0305004124000070_inline3.png\"><span data-mathjax-type=\"texmath\"><span>$rho;:;thinspace Pi_1(S) to SL(nmathbb{R})$</span></span></img></span></span> of discrete, faithful, and Zariski dense representations of a surface group such that <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240325160819198-0562:S0305004124000070:S0305004124000070_inline4.png\"><span data-mathjax-type=\"texmath\"><span>$rho_t(Pi_1(S)) subset SL(n,mathbb{Q})$</span></span></img></span></span> for every <span><span><img data-mimesubtype=\"png\" data-type=\"\" src=\"https://static.cambridge.org/binary/version/id/urn:cambridge.org:id:binary:20240325160819198-0562:S0305004124000070:S0305004124000070_inline5.png\"><span data-mathjax-type=\"texmath\"><span>$tin mathbb{Q}$</span></span></img></span></span>.</p>","PeriodicalId":18320,"journal":{"name":"Mathematical Proceedings of the Cambridge Philosophical Society","volume":"32 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140301301","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}