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 Subjects -> MATHEMATICS (Total: 1021 journals)     - APPLIED MATHEMATICS (83 journals)    - GEOMETRY AND TOPOLOGY (21 journals)    - MATHEMATICS (757 journals)    - MATHEMATICS (GENERAL) (43 journals)    - NUMERICAL ANALYSIS (22 journals)    - PROBABILITIES AND MATH STATISTICS (95 journals) MATHEMATICS (757 journals)            First | 1 2 3 4
 Showing 401 - 538 of 538 Journals sorted alphabetically Journal of K-Theory Journal of Knot Theory and Its Ramifications       (Followers: 1) Journal of Kufa for Mathematics and Computer       (Followers: 1) Journal of Liquid Chromatography & Related Technologies       (Followers: 7) Journal of Logical and Algebraic Methods in Programming Journal of Manufacturing Systems       (Followers: 4) Journal of Mathematical Analysis and Applications       (Followers: 3) Journal of mathematical and computational science       (Followers: 7) Journal of Mathematical and Fundamental Sciences Journal of Mathematical Behavior       (Followers: 2) Journal of Mathematical Chemistry       (Followers: 3) Journal of Mathematical Cryptology       (Followers: 1) Journal of Mathematical Extension       (Followers: 3) Journal of Mathematical Finance       (Followers: 7) Journal of Mathematical Imaging and Vision       (Followers: 6) Journal of Mathematical Logic       (Followers: 2) Journal of Mathematical 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Applications       (Followers: 4) Numerical Mathematics : Theory, Methods and Applications Numerische Mathematik Open Journal of Discrete Mathematics       (Followers: 5) Open Journal of Modelling and Simulation       (Followers: 1) Open Mathematics       (Followers: 1) Operations Research Letters       (Followers: 11) Optimization Letters       (Followers: 2) Optimization Methods and Software       (Followers: 7) Opuscula Mathematica       (Followers: 108) Order ORiON P-Adic Numbers, Ultrametric Analysis, and Applications PAMM : Proceedings in Applied Mathematics and Mechanics       (Followers: 1) Parallel Processing Letters       (Followers: 3) Periodica Mathematica Hungarica       (Followers: 1) Perspectivas da Educação Matemática Petroleum Science       (Followers: 1) Philosophia Mathematica       (Followers: 1) Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences       (Followers: 6) PNA. Revista de Investigación en Didáctica de la Matemática Polar Science       (Followers: 3) Positivity Prague Bulletin of Mathematical Linguistics, The Press Start Prime Number PRIMS Probability in the Engineering and Informational Sciences       (Followers: 1) Problemy Peredachi Informatsii Proceedings - Mathematical Sciences       (Followers: 5) Proceedings of the American Mathematical Society, Series B       (Followers: 1) Proceedings of the Edinburgh Mathematical Society Proceedings of the Institution of Civil Engineers - Engineering and Computational Mechanics       (Followers: 2) Proceedings of the Latvian Academy of Sciences. Section B: Natural, Exact and Applied Sciences

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Similar Journals
 Journal of the London Mathematical SocietyJournal Prestige (SJR): 2.067 Citation Impact (citeScore): 1Number of Followers: 2      Hybrid journal (It can contain Open Access articles) ISSN (Print) 0024-6107 - ISSN (Online) 1469-7750 Published by Oxford University Press  [406 journals]
• Bifurcation of solutions to the Allen–Cahn equation
• Authors: Smith G.
Pages: 667 - 687
Abstract: We use Morse homology to study bifurcation of the solution sets of the Allen–Cahn Equation.
PubDate: Sat, 17 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw053
Issue No: Vol. 94, No. 3 (2016)

• From isolated subgroups to generic permutation representations
• Authors: Glasner YY; Kitroser DD, Melleray JJ.
Pages: 688 - 708
Abstract: Let $G$ be a countable group, ${\rm Sub}(G)$ be the (compact, metric) space of all subgroups of $G$ with the Chabauty topology and ${\rm Is}(G) \subseteq {\rm Sub}(G)$ be the collection of isolated points. We denote by $X!$ the (Polish) group of all permutations of a countable set $X$. Then the following properties are equivalent: (i) ${\rm Is}(G)$ is dense in ${\rm Sub}(G)$; (ii) $G$ admits a ‘generic permutation representation’. Namely, there exists some $\tau ^* \in {\rm Hom}(G,X!)$ such that the collection of permutation representations $\{\varphi \in {\rm Hom}(G,X!) \, \, \varphi \ {\hbox {is permutation isomorphic to}}\ \tau ^*\}$ is co-meager in ${\rm Hom}(G,X!)$. We call groups satisfying these properties solitary. Examples of solitary groups include finitely generated locally extended residually finite groups and groups with countably many subgroups.
PubDate: Wed, 28 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw054
Issue No: Vol. 94, No. 3 (2016)

• Local cohomology with support in ideals of symmetric minors and Pfaffians
• Authors: Raicu C; Weyman J.
Pages: 709 - 725
Abstract: We compute the local cohomology modules $\mathcal {H}_Y^{\bullet }(X,\mathcal {O}_X)$ in the case when $X$ is the complex vector space of $n\times n$ symmetric (respectively, skew-symmetric matrices) and $Y$ is the closure of the $\hbox {GL}$-orbit consisting of matrices of any fixed rank, for the natural action of the general linear group $\hbox {GL}$ on $X$. We describe the $\mathcal {D}$-module composition factors of the local cohomology modules, and compute their multiplicities explicitly in terms of generalized binomial coefficients. One consequence of our work is a formula for the cohomological dimension of ideals of even minors of a generic symmetric matrix: in the case of odd minors, this was obtained by Barile in the 1990s. Another consequence of our work is that we obtain a description of the decomposition into irreducible $\hbox {GL}$-representations of the local cohomology modules (the analogous problem in the case when $X$ is the vector space of $m\times n$ matrices was treated in earlier work of the authors).
PubDate: Sat, 17 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw056
Issue No: Vol. 94, No. 3 (2016)

• Orthogonal polynomials, reproducing kernels, and zeros of optimal
approximants
• Authors: Bénéteau C; Khavinson D, Sola AA, et al.
Pages: 726 - 746
Abstract: We study connections between orthogonal polynomials, reproducing kernel functions, and polynomials $p$ minimizing Dirichlet-type norms $\ pf-1\ _{\alpha }$ for a given function $f$. For $\alpha \in [0,1]$ (which includes the Hardy and Dirichlet spaces of the disk) and general $f$, we show that such extremal polynomials are non-vanishing in the closed unit disk. For negative $\alpha$, the weighted Bergman space case, the extremal polynomials are non-vanishing on a disk of strictly smaller radius, and zeros can move inside the unit disk. We also explain how $\mathrm {dist}_{D_{\alpha }}(1,f\cdot \mathcal {P}_n)$, where $\mathcal {P}_n$ is the space of polynomials of degree at most $n$, can be expressed in terms of quantities associated with orthogonal polynomials and kernels, and we discuss methods for computing the quantities in question.
PubDate: Tue, 20 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw057
Issue No: Vol. 94, No. 3 (2016)

• Representation embeddings, interpretation functors and controlled wild
algebras
• Authors: Gregory L; Prest M.
Pages: 747 - 766
Abstract: We establish a number of results which say, roughly, that interpretation functors preserve algebraic complexity.First, we show that representation embeddings between categories of modules of finite-dimensional algebras induce embeddings of lattices of pp formulas, and hence are non-decreasing on Krull–Gabriel dimension and uniserial dimension. A consequence is that the category of modules of any wild finite-dimensional algebra has width $\infty$, and hence, if the algebra is countable, there is a superdecomposable pure-injective representation.It is conjectured that a stronger result is true: that a representation embedding from ${\rm Mod}\hbox {-}S$ to ${\rm Mod}\hbox {-}R$ admits an inverse interpretation functor from its image, and hence that, in this case, ${\rm Mod}\hbox {-}R$ interprets ${\rm Mod}\hbox {-}S$. This would imply, for instance, that every wild category of modules interprets the (undecidable) word problem for (semi)groups. We show that the conjecture holds for finitely controlled representation embeddings.Finally, we prove that if $R,S$ are finite-dimensional algebras over an algebraically closed field and $I:{\rm Mod}\hbox {-}R\rightarrow {\rm Mod}\hbox {-}S$ is an interpretation functor such that the smallest definable subcategory containing the image of $I$ is the whole of ${\rm Mod}\hbox {-}S,$ then if $R$ is tame, so is $S$ and, similarly, if $R$ is domestic, then $S$ also is domestic.
PubDate: Tue, 27 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw055
Issue No: Vol. 94, No. 3 (2016)

• A conditional determination of the average rank of elliptic curves
• Authors: Fiorilli D.
Pages: 767 - 792
Abstract: Under a hypothesis that is stronger than the Riemann Hypothesis for elliptic curve $L$-functions, we show that both average analytic and algebraic ranks of elliptic curves in families of quadratic twists are exactly $\frac {1}{2}$. As a corollary we obtain that, under this last hypothesis, the Birch and Swinnerton-Dyer Conjecture holds for almost all curves, and that asymptotically one-half have algebraic rank 0, and the remaining half 1. We also prove an analogous result in the family of all elliptic curves. The proof uses results of Katz–Sarnak and Young on the 1-level density of zeros of elliptic curve $L$-functions. In essence, we show that, under a hypothesis analogous to Montgomery's Conjecture, a density result with limited support on low-lying zeros of $L$-functions is sufficient to determine the average rank.
PubDate: Fri, 23 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw058
Issue No: Vol. 94, No. 3 (2016)

• Uniqueness from discrete data in an inverse spectral problem for a pencil
of ordinary differential operators
• Authors: Brown M; Marletta M, Symons F.
Pages: 793 - 813
Abstract: We prove a pair of uniqueness theorems for an inverse problem for an ordinary differential operator pencil of second order. The uniqueness is achieved from a discrete set of data, namely, the values at the points $-n^2\ (n\in \mathbb {N})$ of (a physically appropriate generalization of) the Weyl–Titchmarsh $m$-function $m(\lambda )$ for the problem. As a corollary, we establish a uniqueness result for a physically motivated inverse problem inspired by Berry and Dennis (‘Boundary-condition-varying circle billiards and gratings: the Dirichlet singularity’, J. Phys. A: Math. Theor. 41 (2008) 135203).To achieve these results, we prove a limit-circle analogue to the limit-point $m$-function interpolation result of Rybkin and Tuan (‘A new interpolation formula for the Titchmarsh–Weyl $m$-function’, Proc. Amer. Math. Soc. 137 (2009) 4177–4185); however, our proof, using a Mittag-Leffler series representation of $m(\lambda )$, involves a rather different method from theirs, circumventing the $A$-amplitude representation of Simon (‘A new approach to inverse spectral theory, I. Fundamental formalism’, Ann. Math. $(2)$ 150 (1999) 1029–1057). Uniqueness of the potential then follows by appeal to a Borg–Marčenko argument.
PubDate: Sat, 17 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw059
Issue No: Vol. 94, No. 3 (2016)

• Mean value estimates for Weyl sums in two dimensions
• Authors: Bourgain J; Demeter C.
Pages: 814 - 838
Abstract: We use decoupling theory to estimate the number of solutions for quadratic and cubic Parsell–Vinogradov systems in two dimensions.
PubDate: Thu, 06 Oct 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw063
Issue No: Vol. 94, No. 3 (2016)

• Limit algebras and integer-valued cocycles, revisited
• Authors: Katsoulis EG; Ramsey C.
Pages: 839 - 858
Abstract: A triangular limit algebra ${\mathcal {A}}$ is isometrically isomorphic to the tensor algebra of a $C^{\ast }$-correspondence if and only if its fundamental relation ${\mathcal {R}}( {\mathcal {A}})$ is a tree admitting a ${\mathbb {Z}}^+_0$-valued continuous and coherent cocycle. For triangular limit algebras which are isomorphic to tensor algebras, we give a very concrete description for their defining ${C}^{\ast }$-correspondence, and we show that it forms a complete invariant for isometric isomorphisms between such algebras. A related class of operator algebras is also classified using a variant of the Aho–Hopcroft–Ullman algorithm from computer-aided graph theory.
PubDate: Wed, 28 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw060
Issue No: Vol. 94, No. 3 (2016)

• Multiple positive solutions of parabolic systems with nonlinear, nonlocal
initial conditions
• Authors: Infante G; Maciejewski M.
Pages: 859 - 882
Abstract: In this paper, we study the existence, localization and multiplicity of positive solutions for parabolic systems with nonlocal initial conditions. In order to do this, we extend an abstract theory that was recently developed by the authors jointly with Radu Precup, related to the existence of fixed points of nonlinear operators satisfying some upper and lower bounds. Our main tool is the Granas fixed-point index theory. We also provide a nonexistence result and some examples to illustrate our theory.
PubDate: Sat, 17 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw061
Issue No: Vol. 94, No. 3 (2016)

• Geometrically and diagrammatically maximal knots
• Authors: Champanerkar A; Kofman I, Purcell JS.
Pages: 883 - 908
Abstract: The ratio of volume to crossing number of a hyperbolic knot is known to be bounded above by the volume of a regular ideal octahedron, and a similar bound is conjectured for the knot determinant per crossing. We investigate a natural question motivated by these bounds: For which knots are these ratios nearly maximal' We show that many families of alternating knots and links simultaneously maximize both ratios.
PubDate: Fri, 23 Sep 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw062
Issue No: Vol. 94, No. 3 (2016)

• Triple Massey products vanish over all fields
• Authors: Mináč J; Tân N.
Pages: 909 - 932
Abstract: We show that the absolute Galois group of any field has the vanishing triple Massey product property. Several corollaries for the structure of maximal pro-$p$-quotient of absolute Galois groups are deduced. Furthermore, the vanishing of some higher Massey products is proved.
PubDate: Fri, 21 Oct 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw064
Issue No: Vol. 94, No. 3 (2016)

• The augmented marking complex of a surface
• Authors: Durham M.
Pages: 933 - 969
Abstract: We build an augmentation of the Masur–Minsky marking complex by Groves-Manning combinatorial horoballs to obtain a graph we call the augmented marking complex, $\mathcal {AM}(S)$. Adapting work of Masur–Minsky, we show that this augmented marking complex is quasiisometric to Teichmüller space with the Teichmüller metric. A similar construction was independently discovered by Eskin–Masur–Rafi. We also completely integrate the Masur–Minsky hierarchy machinery to $\mathcal {AM}(S)$ to build flexible families of uniform quasigeodesics in Teichmüller space. As an application, we give a new proof of Rafi's distance formula for $\mathcal {T}(S)$ with the Teichmüller metric. We have included an appendix, in which we prove a number of facts about hierarchies that we hope will be of independent interest.
PubDate: Fri, 21 Oct 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw065
Issue No: Vol. 94, No. 3 (2016)

• Legendrian contact homology in the product of a punctured Riemann surface
and the real line
• Authors: Björklund J.
Pages: 970 - 992
Abstract: We give a combinatorial description of the Legendrian differential graded algebra associated to a Legendrian knot in $P\times {\mathbb R}$, where $P$ is a punctured Riemann surface. As an application we show that, for any integer $k$ and any homology class $h\in H_1(P\times {\mathbb R})$, there are $k$ Legendrian knots, all representing $h$, which are pairwise smoothly isotopic through a formal Legendrian isotopy, but which lie in mutually distinct Legendrian isotopy classes.
PubDate: Tue, 08 Nov 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw066
Issue No: Vol. 94, No. 3 (2016)

• The maximum product of weights of cross-intersecting families
• Authors: Borg P.
Pages: 993 - 1018
Abstract: A set of sets is called a family. Two families $\mathcal {A}$ and $\mathcal {B}$ are said to be cross-$t$-intersecting if each set in $\mathcal {A}$ intersects each set in $\mathcal {B}$ in at least $t$ elements. An active problem in extremal set theory is to determine the maximum product of sizes of cross-$t$-intersecting subfamilies of a given family. This incorporates the classical Erdös–Ko–Rado (EKR) problem. We prove a cross-$t$-intersection theorem for weighted subsets of a set by means of a new subfamily alteration method, and use the result to provide solutions for three natural families. For $r \in [n] = \{1, 2,\ldots , n\}$, let ${[n] \choose r}$ be the family of $r$-element subsets of $[n]$, and let ${[n] \choose \leq r}$ be the family of subsets of $[n]$ that have at most $r$ elements. Let $\mathcal {F}_{n,r,t}$ be the family of sets in ${[n] \choose \leq r}$ that contain $[t]$. We show that if $g : {[m] \choose \leq r} \rightarrow \mathbb {R}^+$ and $h : {[n] \choose \leq s} \rightarrow \mathbb {R}^+$ are functions that obey certain conditions, $\mathcal {A} \subseteq {[m] \choose \leq r}$, $\mathcal {B} \subseteq {[n] \choose \leq s}$, and $\mathcal {A}$ and $\mathcal {B}$ are cross-$t$-intersecting, then $\sum_{A \in \mathcal{A}} g(A) \sum_{B \in \mathcal{B}} h(B) \leq \sum_{C \in \mathcal{F}_{m,r,t}} g(C) \sum_{D \in \mathcal{F}_{n,s,t}} h(D),$ and equality holds if $\mathcal {A} = \mathcal {F}_{m,r,t}$ and $\mathcal {B} = \mathcal {F}_{n,s,t}$. We prove this in a more general setting and characterize the cases of equality. We use the result to show that the maximum product of sizes of two cross-$t$-intersecting families $\mathcal {A} \subseteq {[m] \choose r}$ and $\mathcal {B} \subseteq {[n] \choose s}$ is ${m-t \choose r-t}{n-t \choose s-t}$ for $\min \{m,n\} \geq n_0(r,s,t)$, where $n_0(r,s,t)$ is close to best possible. We obtain analogous results for families of integer sequences and for families of multisets. The results yield generalizations for $k \geq 2$ cross-$t$-intersecting families, and EKR-type results.
PubDate: Tue, 08 Nov 2016 00:00:00 GMT
DOI: 10.1112/jlms/jdw067
Issue No: Vol. 94, No. 3 (2016)

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