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🔍 erick chandra 📂 Mathematics
Showing 1484 results for "erick chandra" in Mathematics
Mathematics Preprint PDF DOI

A torsion-intersection proof of perfect-cuboid nonexistence on 1,072 explicit master-tuple fibers

Rene Peschmann · 2026

Building on the genus-3 reduction $C_A : w^2 = \lambda^8 + A \lambda^4 + 1$ established in our companion paper (arXiv:2604.09328), we give an unconditional proof of the perfect-cuboid conjecture ("Con…

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Mathematics Preprint PDF DOI

Weighted Linearization of Vector Fields via a Formal Moser Trick

Arthur Lei Qiu · 2026

Many well-known theorems establish sufficient criteria for linearizability of a vector field in terms of the eigenvalues of its linear approximation. By attaching weights to coordinates so that some d…

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Mathematics Preprint PDF DOI

Lagrangian reduction of symmetric discrete mechanical systems: a survey

Matias I. Caruso, Javier Fernandez, Cora Tori, Marcela Zuccalli · 2026

In this note we survey some of our results on the Lagrangian reduction of discrete-time mechanical systems (DMSs). It is intended as an introduction to the general ideas that we used in the reduction …

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Mathematics Preprint PDF DOI

Left modularity and extremality for (some) infinite lattices

Sota Asai, Osamu Iyama, Kaveh Mousavand, Charles Paquette · 2026

For some important families of complete infinite lattices, we study some generalizations of two fundamental notions which are mostly treated for finite lattices. Specifically, for well-separated $\kap…

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Mathematics Preprint PDF DOI

Explicit counting of ideals in number fields of arbitrary degree

Anton Fehnker · 2026

We implement methods from the geometry of numbers to give explicit estimates for the number of integral ideals in a number field. We pay particular attention to minimising the effect of the degree $n$…

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Mathematics Preprint PDF DOI

On local integrability results for $p$-adic reductive groups

Cheng-Chiang Tsai · 2026

We present a short proof, based on local character expansions, of the celebrated theorem of Harish-Chandra about local integrability of complex characters of $p$-adic reductive groups. The proof gives…

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Mathematics Preprint PDF DOI

Equivariant L-Classes of Atiyah-Singer-Zagier Type for Singular Spaces

Markus Banagl · 2026

If a finite group $G$ acts on a rational homology manifold, then the orbit space is well-known to be a rational homology manifold again. We consider here actions on spaces that may be much more singul…

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Mathematics Preprint PDF DOI

All knots are trivial: a "proof" by sleight of hand

Raphael Appenzeller, Jose Pedro Quintanilha · 2026

We take a close look at a classical magic trick performed with a string, where a trivial knot is seemingly isotoped into a trefoil, and generalize it to a family of magic tricks for transforming the u…

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Mathematics Preprint PDF DOI

On the Cotlar-Stein lemma

Michael Hartz, Marcel Scherer · 2026

We give a direct proof of the Cotlar-Stein lemma, which does not rely on the power trick.…

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Mathematics Preprint PDF DOI

RKHS method for computing Koopman-based Lyapunov functions

Francois-Gregoire Bierwart, Alexandre Mauroy · 2026

The Koopman operator is a powerful approach to global stability analysis of nonlinear systems, which provides a systematic procedure for Lyapunov function design. In this framework, Lyapunov functions…

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Mathematics Preprint PDF DOI

Quartic reductions and elliptic obstructions for perfect Euler bricks

Rene Peschmann · 2026

We show that the perfect Euler brick (perfect cuboid) problem is equivalent to the following elementary question: do there exist coprime integers $a, b, m, n$ such that the two expressions $(2(a^2-b^2…

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Mathematics Preprint PDF DOI

A criterion for Tits alternative on the centralizer of a matrix

Adem Zeghib · 2026

We give a necessary and sufficient condition on a matrix for its centralizer in $\sf{GL}(n,\mathbb{Z})$ to be polycyclic, or equivalently in this case, not to contain a non-abelian free subgroup. We g…

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Mathematics Preprint PDF DOI

Non-isotopic surfaces in $T^4\#(S^2\times S^2)$: an example

Jianfeng Lin, Yue Wu · 2026

We prove that there exist infinitely many embedded tori with a common geometric dual in $T^4\#(S^2\times S^2)$ that are homotopic, diffeomorphic, but not isotopic to each other, even after arbitrary m…

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Mathematics Preprint PDF DOI

Bicompact torsion classes and conjectures on brick infinite algebras

Sota Asai · 2026

A torsion class $\mathcal{T}$ of the module category $\operatorname{\mathsf{mod}} A$ of a finite dimensional algebra $A$ over a field $K$ is said to be compact if there exists a module $M \in \operato…

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Mathematics Preprint PDF DOI

Representation theory of the Gelfand quiver and Harish-Chandra modules for $\mathsf{SL}_2(\mathbb{R})$

Igor Burban, Wassilij Gnedin · 2026

In 1970, Gelfand posed the problem of classifying the indecomposable objects in a representation category equivalent to the principal block of Harish-Chandra modules for $\mathsf{SL}_2(\mathbb{R})$; e…

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Mathematics Preprint PDF DOI

Parabolic conjugacy class in finite reductive groups and its additive analogue

GyeongHyeon Nam · 2026

In this paper, we answer the question posed by Goodwin and R\"ohrle for reductive groups and their parabolic subgroups. In addition, we consider an additive analogue of this problem. By studying this …

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Mathematics Preprint PDF DOI

The theta correspondence over finite fields

Anne-Marie Aubert · 2026

This set of lecture notes is an expanded version of a mini-course the author gave in March of 2025 for the program ``Representation Theory \& Noncommutative Geometry" at the Institut Henri Poincar\'e,…

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Mathematics Preprint PDF DOI

An automata-based test for bricks over string algebras

Amit Kuber, Annoy Sengupta · 2026

Motivated by the recent work of Deaconu, Mousavand and Paquette on the connection between infinite string bricks for certain gentle algebras and Sturmian words, we develop a decorated version of a det…

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Mathematics Preprint PDF DOI

A vanishing theorem for residual Eisenstein cohomology

Sam Mundy · 2026

We study the residual Eisenstein cohomology of semisimple groups in the context of maximal parabolic subgroups which remain maximal over $\mathbb{R}$. Under certain general hypotheses, we show that th…

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Mathematics Preprint PDF DOI

A Structure-Preserving LOBPCG Algorithm for the Bethe-Salpeter Eigenvalue Problem

Xinyu Shan, Meiyue Shao · 2026

The Bethe-Salpeter eigenvalue problem is a structured eigenvalue problem arising in many-body physics. In practice, a few of the smallest positive eigenvalues and the corresponding eigenvectors need t…

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