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作者:Alper, Jarod; Hall, Jack; Rydh, David
摘要:We prove that every algebraic stack, locally of finite type over an algebraically closed field with affine stabilizers, is (tale-locally a quotient stack in a neighborhood of a point with a linearly reductive stabilizer group. The proof uses an equivariant version of Artin's algebraization theorem proved in the appendix. We provide numerous applications of the main theorems.
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作者:Petrow, Ian; Young, Matthew P.
摘要:We prove a Weyl-exponent subconvex bound for any Dirichlet L-function of cube-free conductor. We also show a bound of the same strength for certain L-functions of self-dual GL(2) automorphic forms that arise as twists of forms of smaller conductor.
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作者:Judge, Chris; Mondal, Sugata
摘要:We show that a second Neumann eigenfunction u of a Euclidean triangle has at most one (non-vertex) critical point p, and if p exists, then it is a non-degenerate critical point of Morse index 1. Using this we deduce that (1) the extremal values of u are only achieved at a vertex of the triangle, and (2) a generic acute triangle has exactly one (non-vertex) critical point and that each obtuse triangle has no (non-vertex) critical points. This settles the hot spots conjecture for triangles in th...
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作者:Branden, Petter; Huh, June
摘要:We study the class of Lorentzian polynomials. The class contains homogeneous stable polynomials as well as volume polynomials of convex bodies and projective varieties. We prove that the Hessian of a nonzero Lorentzian polynomial has exactly one positive eigenvalue at any point on the positive orthant. This property can be seen as an analog of the Hodge-Riemann relations for Lorentzian polynomials. Lorentzian polynomials are intimately connected to matroid theory and negative dependence proper...
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作者:Angenent, Sigurd; Daskalopoulos, Panagiota; Sesum, Natasa
摘要:In this paper we consider the classification of closed non-collapsed ancient solutions to the Mean Curvature Flow (n >= 2) that are uniformly two-convex. We prove that they are either contracting spheres or they must coincide up to translations and scaling with the rotationally symmetric closed ancient non-collapsed solution first constructed by Brian White, and later by Robert Haslhofer and Or Hershkovits.
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作者:Guth, Larry; Wang, Hong; Zhang, Ruixiang
摘要:We prove a sharp square function estimate for the cone in R-3 and consequently the local smoothing conjecture for the wave equation in 2 + 1 dimensions.
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作者:Koukoulopoulos, Dimitris; Maynard, James
摘要:Let psi : N -> R->= 0 be an arbitrary function from the positive integers to the non-negative reals. Consider the set A of real numbers a for which there are infinitely many reduced fractions a/q such that vertical bar alpha-a/q vertical bar <= psi(q)/q. If Sigma(infinity)(q=1) psi(q)phi(q)/q = infinity, we show that A has full Lebesgue measure. This answers a question of Duffin and Schaeffer. As a corollary, we also establish a conjecture due to Catlin regarding non-reduced solutions to the i...
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作者:DeMarco, Laura; Krieger, Holly; Ye, Hexi
摘要:We introduce a general strategy for proving quantitative and uniform bounds on the number of common points of height zero for a pair of inequivalent height functions on P-1((Q) over bar). We apply this strategy to prove a conjecture of Bogomolov, Fu, and Tschinkel asserting uniform bounds on the number of common torsion points of elliptic curves in the case of two Legendre curves over C. As a consequence, we obtain two uniform bounds for a two-dimensional family of genus 2 curves: a uniform Ma...
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作者:Goette, S.; Kerin, M.; Shankar, K.
摘要:In this article, a six-parameter family of highly connected 7-manifolds which admit an SO(3)-invariant metric of non-negative sectional curvature is constructed and the Eells-Kuiper invariant of each is computed. In particular, it follows that all exotic spheres in dimension 7 admit an SO(3)-invariant metric of non-negative curvature.
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作者:Rizzardo, Alice; Van den Bergh, Michel
摘要:In this paper we give an example of a triangulated category, linear over a field of characteristic zero, which does not carry a DG-enhancement. The only previous examples of triangulated categories without a model have been constructed by Muro, Schwede and Strickland. These examples are however not linear over a field.