A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.
We prove that every embedding of K2n+1,2n+1 into R3 contains a non-split link of n-components. Further, given an embedding of K2n+1,2n+1 in R3, every edge of K2n+1,2n+1 is contained in a non-split n-component link in K2n+1,2n+1.
Let J(S2n) be the set of orthogonal complex structures on TS2n. We show that the twistor space J(S2n) is a Kaehler manifold. Then we show that an orthogonal almost complex structure Jf on S2n is integrable if and only if the corresponding section $f\colon\; S^{2n…
Let L be a link and ΦLA(q) its link invariant associated with the vector representation of the quantum (super)algebra Uq(A). Let FL(r,s) be the Kauffman link invariant for L associated with the Birman--Wenzl--Murakami algebra BWMf(r,s) for complex parameters r and s and a sufficiently lar…
Let M2n denote a closed (n−1)-connected smoothable topological 2n-manifold. We show that the group C(M2n) of concordance classes of smoothings of M2n is isomorphic to the group of smooth homotopy spheres Θ2n for n=4 or 5, the concordance inertia group Ic(M2n)=0 for $…
We study the moduli space of handlebodies diffeomorphic to (Dn+1×Sn)♮g, i.e. the classifying space BDiff((Dn+1×Sn)♮g,D2n) of the group of diffeomorphisms that restrict to the identity near a 2n-dimensional disk embedded in the boundary, $\partial(D^{n+1}\times S^n)^…
As an application of `reverse engineering' technique introduced by R. Fintushel, D. Park and R. Stern \cite{FPS}, we construct an infinite family of fake (2n+2l-1)CP^2#(2n+4l-1)(-CP^2)'s for all n \ge 0, l \ge 1.
We prove that many pretzel knots of the form P(2n,m,−2n±1,−m) are not topologically slice, even though their positive mutants P(2n,−2n±1,m,−m) are ribbon. We use the sliceness obstruction of Kirk and Livingston related to the twisted Alexander polynomials associated to prime power cyclic covers of knots.
The Hopf invariant is linked to null-homotopy properties of maps.
problem Understanding the relationship between the Hopf invariant and null-homotopy of maps.
method Using the generalized Hopf invariant and constructing smooth null-homotopies, the paper explores the relationship between the Hopf invariant and null-homotopy properties of maps.
result Sharp results on the relationship between the Hopf invariant and null-homotopy properties of maps, showing the necessity and sufficiency of certain conditions.
We show that an n-dimensional compactum X embeds in R^m, where m>3(n+1)/2, if and only if X x X - Δadmits an equivariant map to S^{m-1}. In particular, X embeds in R^{2n}, n>3, iff the top power of the (twisted) Euler class of the factor-exchanging involution on X x X - Δis trivial. Assuming that X quasi-embeds in R^{2…
Let Hg be a genus g handlebody and MCG2n(Tg) be the group of the isotopy classes of orientation preserving homeomorphisms of Tg=∂Hg, fixing a given set of 2n points. In this paper we find a finite set of generators for E2ng, the subgro…
The paper defines and proves a new property for symplectic manifolds.
problem The study introduces a new property for symplectic manifolds.
method Defines and proves the L2-hard Lefschetz property for complete symplectic manifolds.
result Proves that a complete symplectic manifold satisfies the L2-hard Lefschetz property if and only if every class of L2-harmonic forms contains a L2 symplectic harmonic form.
An explicit (-1)^n-quadratic form over Z[Z^{2n}] representing the surgery problem E_8 x T^{2n} is obtained, for use in the Bryant-Ferry-Mio-Weinberger construction of 2n-dimensional exotic homology manifolds.
C-projective structures are analogues of projective structures in the complex setting. The maximal dimension of the Lie algebra of c-projective symmetries of a complex connection on an almost complex manifold of C-dimension n>1 is classically known to be 2n2+4n. We prove that the submaximal dimension is equal to $…
We construct new complete, compact, inhomogeneous Einstein metrics on S^{m+2} sphere bundles over 2n-dimensional Einstein-Kahler spaces K_{2n}, for all n \ge 1 and all m \ge 1. We also obtain complete, compact, inhomogeneous Einstein metrics on warped products of S^m with S^2 bundles over K_{2n}, for m>1. Additionally,…
We show that there is no complex structure in a neighborhood of the space of orthogonal almost complex structures on the sphere S2n,n>1. The method is to study the first Chern class of vetcor bundle T(1,0)S2n.
We show the local rigidity of complex hyperbolic lattices in classical Hermitian semisimple Lie groups, SU(np,p),Sp(2n+2,R),SO∗(2n+2),SO(2n,2). This reproves or generalizes some results in \cite{GM, KKP, Klingler-inv, Pozzetti}.
Let M2n−1 be the smooth boundary of a bounded strongly pseudo-convex domain Ω in a complete Stein manifold V2n. Then (1) For n≥3, M2n−1 admits a pseudo-Eistein metric; (2) For n≥2, M2n−1 admits a Fefferman metric of zero CR Q-curvature; and (3) for a compact strictly pseudoconvex CR em…
The twistor space of the sphere S^{2n} is an isotropic Grassmannian that fibers over S^{2n}. An orthogonal complex structure on a subdomain of S^{2n} (a complex structure compatible with the round metric) determines a section of this fibration with holomorphic image. In this paper, we use this correspondence to prove t…
We establish lower bounds on the dimensions in which arithmetic groups with torsion can act on acyclic manifolds and homology spheres. The bounds rely on the existence of elementary p-groups in the groups concerned. In some cases, including Sp(2n,Z), the bounds we obtain are sharp: if X is a generalized Z/3-homology sp…
We record various properties of twisted Becker-Gottlieb transfer maps and study their multiplicative properties analogous to Becker-Gottlieb transfer. We show these twisted transfer maps factorise through Becker-Schultz-Mann-Miller-Miller transfer; some of these might be well known. We apply this to show that $BSO(2n+1…
We create Resthetikhin-Turaev topological invariants of closed orientable three-manifolds from the quantum supergroup U_q(osp(1|2n)) at certain even roots of unity. To construct the invariants we develop tensor product theorems for finite dimensional modules of U_q(osp(1|2n)) at roots of unity.
We classify symplectic actions of 2-tori on compact, connected symplectic 4-manifolds, up to equivariant symplectomorphisms. This extends results of Atiyah, Guillemin-Sternberg, Delzant and Benoist. The classification is in terms of a collection of invariants, which are invariants of the topology of the manifold, of th…
We classify generalized distance-squared mappings of Rn+1 into R2n+1 (n≥1) having generic central points. Moreover, we show that there does not exist a universal bad set Σ⊂(Rn+1)2n+1 in the case of this dimension-pair.
In this note we describe the recursion relations between two parameter HOMLFY and Kauffman polynomials of framed links These relation correspond to embeddings of quantized universal enveloping algebras. The relation corresponding to embeddings gn⊃gk×sln−k where gn is either so2n+1, $so…
In this paper, using exclusively homotopy theoretical methods, we study degrees of maps between (n−2)-connected (2n−1)-dimensional Poincar\' e complexes which have torsion free integral homology. Necessary and sufficient algebraic conditions for the existence of map degrees between such Poincar\' e complexes are es…