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Isomorphism of varieties in $\mathbb{C}$ implies isomorphism over finite fields

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a_g

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Relative Lie algebra cohomology

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truebaran

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Does the first Laplacian eigenfunction on a homogeneous space have a unique maximum?

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user404153

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Who was the first to formulate the inverse function theorem?

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john

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Is there a non-degenerate quadratic form on every finite abelian group?

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Sebastien Palcoux

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How much downward density can we get without injury?

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Noah Schweber

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What is the intersection of all ideals whose radicals are prime?

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P-addict

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Nielsen equivalence in one-relator groups

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ADL

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Integral inequality: an elementary proof?

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Denis Serre

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Let $X$ be a finite set of $n$ ($>1$) elements and $\tau$ be a topology on $X$ having exactly $m$ elements. Can we give any description of $m$?

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Sourav Ghosh

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Real-Closed Fields and Intermediate Value Theorem

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Philip Ehrlich

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Understanding a simplifying assumption in Invariant Subspace Problem proof

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Federico

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natural metrics for proof length

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Aidan Rocke

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Proving an identity about Catalan numbers

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banana

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Group of matrices in which every matrix is similar to unitary

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Александр Худяков

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How to calculate the inverse of the sum of an identity and a Kronecker product efficiently?

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ppyang

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Are the polynomials in $\{1/t\}$ dense in $L^2(0,1)$?

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Vesselin Dimitrov

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For a finite set A of positive reals, prove that the set A + A - A contains at least as many positive as negative elements

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Timo Reichert

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Borel sets with almost equal sections

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Vladimir Kanovei

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Big list: barycentric subdivision of simplicial sets

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Dry Bones

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Making perpetual motion machine from candy-sharing cats

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Eric

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Explicit isomorphism for quaternion algebras over $\mathbb{Q}$?

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benblumsmith

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What are TQFTs that are multiplicative under connected sums? Do bordisms with connected sum as monoidal product exist?

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Manuel Bärenz

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Any reference on multilinear algebra [closed]

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mingming

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Is a generic genus $g \geq 7$ curve a solvable cover of $\mathbb{P}^1$?

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David E Speyer

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Exterior powers in tensor categories

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Martin Brandenburg

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Are there any fields of academic mathematics whose epistemic status as math is controversial within the academic community?

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tparker

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Equivariant cohomology of the complement to the arrangement $\bigcup_{i\neq j}\vec x_i = \vec x_j$?

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Anton Khoroshkin

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The scope of a "strong Cantor-Bernstein" property

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Noah Schweber

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Can the equation $1+z+z^2=z^n$ for natural $n$ have multiple complex roots $z$?

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Iosif Pinelis

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What does "cohomologically proper of dimension n" mean?

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Makhalan Duff

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What is the shape of the perfect coffee cup for heat retention assuming coffee is being drunk at a constant rate?

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MichaelMcL1960

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Strong uniqueness of Euler's totient function

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Alexander Kalmynin

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Lipschitz property of the determinant

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Iosif Pinelis

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Probabilistic solution of the porous medium equation

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Alexander Moll

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Variation of the Einstein Hilbert action in a coordinate-free way

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Chris

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Almost everywhere “filling” of the continuum by the first uncountable cardinal without CH

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David Petey Gao

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Is the eigenvalue map open?

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Lucas Seco

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Orthogonal vectors with entries from $\{-1,0,1\}$

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Nathaniel Johnston

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Clausen's modified Hodge Conjecture

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Jan

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An application of ping-pong lemma

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Shiv Parsad

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Example of continuous cohomology vs cohomology

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Echo

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Invariant cohomology vs cohomology of quotient

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Mattis Bakken

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On sums of cubes of four integer valued polynomials

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Chris

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Would it be possible to propose a satisfying categorical definition for the notion of basis?

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Contactomorph

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Is there a good reference for the relationship between the Yangian and formal based loop group?

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Ben Webster♦

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Is it consistent with ZFC(A) for the Hartogs number of a proper class to be $\aleph_0$?

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NoLongerBreathedIn

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Sylvester–Gallai theorem with circle version, plane version and curve version?

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Cố Gắng Lên

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$A \wedge A \wedge A$ in Chern-Simons

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N. Shimode

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On Ramanujan's pi formula $\frac 1\pi=\sum_{k=0}^\infty\frac {(4k)!}{k!^4}\frac {Ak+B}{396^{4k}}$ and the solvable quintic $z^5-5z-396 = 0$?

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Tito Piezas III

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Random Sampling a linearly constrained region in n-dimensions...

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user1

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Naturality of Moore-Postnikov systems

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Mark Grant

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Complex manifolds where bounded holomorphic functions are constant

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Truly

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Which directed graphs have a normal adjacency matrix?

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Mustafa Said

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Lower bounds for Betti numbers of a manifold given its boundary?

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Ignacio Ruiz García

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Does a completely metrizable space admit a compatible metric where all intersections of nested closed balls are non-empty?

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Cla

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Locally Indicable Hyperbolic Groups

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Mahdi Teymuri Garakani

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New method to compute square roots [closed]

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polygamma

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On the field of invariants of a finite group

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Hugo Chapdelaine

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Symmetries of local systems on the punctured sphere

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Daniel Litt

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