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Moshe Adrian

Publications and source records attributed to Moshe Adrian.

At least 19 recordsLinked to original sources
arXiv2025

On sharpness in Local Converse Theorems for classical groups and $G_2$

We prove various results about the Local Converse Problem for split reductive groups $G$ over a non-archimedean local field~$F$ of characteristic $0$ and residual characteristic $p$. In particular, we prove that when $G$ is a symplectic or special orthogonal group, or the exceptional group $G_2$, and $p$ is large enough, then the optimal standard Local Converse Theorem for $G(F)$ requires twisting by representations of $GL_r(F)$ with $r$ up to half the dimension of the standard representation of the dual group of $G$. However, if we restrict to generic supercuspidal representations of $G(F)$ then it can be improved when $G=SO_{2N}$; we conjecture that the same is true for symplectic and odd special orthogonal groups. We also consider the possibility of using non-standard representations of the dual group to distinguish representations, giving counterexamples to possible improvements for general linear groups, $G_2$ and $SO_{2N}$.

math.RT↗
arXiv2023

Simple supercuspidal L-packets of split special orthogonal groups over dyadic fields

We consider the split special orthogonal group $\mathrm{SO}_{N}$ defined over a $p$-adic field. We determine the structure of any $L$-packet of $\mathrm{SO}_{N}$ containing a simple supercuspidal representation (in the sense of Gross--Reeder). We also determine its endoscopic lift to a general linear group. Combined with the explicit local Langlands correspondence for simple supercuspidal representations of general linear groups, this leads us to get an explicit description of the $L$-parameter as a representation of the Weil group of $F$. Our result is new when $p=2$ and our method provides a new proof even when $p\neq2$.

math.NT↗
arXiv2023

A local converse theorem for archimedean GL(n)

We prove a local converse theorem for $GL_n$ over the archimedean local fields which characterizes an infinitesimal equivalence class of irreducible admissible representations of $GL_n(\mathbb{R})$ or $GL_n(\mathbb{C})$ in terms of twisted local gamma factors.

math.RT↗
arXiv2021

Lifting Involutions in a Weyl Group to the Normalizer of the Torus

Let N be the normalizer of a maximal torus T in a split reductive group over F_q, and let w be an involution in the Weyl group N/T. We construct a section of W satisfying the braid relations, such that the image of the lift n of w under the Frobenius map is equal to the inverse of n.

math.RT↗
arXiv2019

The sections of the Weyl group

We compute all sections of the finite Weyl group, that satisfy the braid relations, in the case that G is an almost-simple connected reductive group defined over an algebraically closed field. We then demonstrate that this set of sections has an interesting partially ordered structure, and also give some applications.

math.RT↗
arXiv2019

On the Langlands parameter of a simple supercuspidal representation: even orthogonal groups

Let $\pi$ be a simple supercuspidal representation of the split even special orthogonal group. We compute the Rankin-Selberg $\gamma$-factors for rank 1-twists of $\pi$ by quadratic tamely ramified characters of $F^*$. We then use our results to determine the Langlands parameter of $\pi$ up to its restriction to the wild inertia subgroup, subject to an analogue of a work of Blondel, Henniart, and Stevens for $SO_{2l}$. In the particular case of the field $\mathbb{Q}_2$, we are able to describe the parameter completely.

math.RT↗
arXiv2018

The Langlands parameter of a simple supercuspidal representation: Symplectic groups

Let $\pi$ be a simple supercuspidal representation of the symplectic group $Sp_{2l}(F)$, over a $p$-adic field $F$. In this work, we explicitly compute the Rankin-Selberg $\gamma$-factor of rank-$1$ twists of $\pi$. We then completely determine the Langlands parameter of $\pi$, if $p \neq 2$. In the case that $F = \mathbb{Q}_2$, we give a conjectural description of the functorial lift of $\pi$, with which, using a recent work of Bushnell and Henniart, one can obtain its Langlands parameter.

math.RT↗
arXiv2017

A local converse theorem for GL(n) (archimedean case)

In this paper we prove a local converse theorem for GL_n over the archimedean local fields, which characterizes an infinitesimal equivalence class of irreducible admissible representations of GL_n(R) (or GL_n(C)) in terms of twisted L-factors.

math.RT↗
arXiv2016

A remark on the Kottwitz homomorphism

We prove that for any split almost-simple connected reductive group G over a p-adic field F, the Kottwitz homomorphism exhibits a homomorphic section. We then extend this result to certain additional split connected reductive groups.

math.RT↗
arXiv2015

On the Langlands parameter of a simple supercuspidal representation: odd orthogonal groups

In this work, we explicitly compute a certain family of twisted gamma factors of a simple supercuspidal representation $\pi$ of a $p$-adic odd orthogonal group. These computations, together with analogous computations for general linear groups carried out in previous work with Liu, allow us to give a prediction for the Langlands parameter of $\pi$. If we assume the "depth-preserving conjecture", we prove that our prediction is correct if $p$ is sufficiently large.

math.RT↗
arXiv2014

On the Jacquet Conjecture on the Local Converse Problem for p-adic GL_n

Based on previous results of Jiang, Nien and the third author, we prove that any two minimax unitarizable supercuspidals of GL_N that have the same depth and central character admit a special pair of Whittaker functions. This result gives a new reduction towards a final proof of Jacquet's conjecture on the local converse problem for GL_N. As a corollary of our result, we prove Jacquet's conjecture for GL_N, when N is prime.

math.RT↗
arXiv2014

The Local Langlands Correspondence for Simple Supercuspidal Representations of GL_n(F)

Let F be a non-archimedean local field of characteristic zero with residual characteristic p. In this paper, we present a simple proof and construction of the local Langlands correspondence for simple supercuspidal representations of GL_n(F), when p does not divide n. As an application, we prove Jacquet's conjecture on the local converse problem for GL_n(F) in the case of simple supercuspidal representations, for arbitrary p.

math.RT↗
arXiv2013

Count Models Based on Weibull Interarrival Times

In this paper, we introduce a generalized model for count data based upon an assumed Weibull interarrival process that nests the Poisson and negative binomial models as special cases. In addition, we demonstrate that this new Weibull count model can model both over and underdispersed count data, allow covariates to be introduced in a straightforward manner through the hazard function, and be computed in standard software.

stat.ME↗
arXiv2012

On the Local Langlands Correspondences of DeBacker/Reeder and Reeder for $GL(\ell,F)$, where $\ell$ is prime

We prove that the conjectural depth zero local Langlands correspondence of DeBacker/Reeder agrees with the depth zero local Langlands correspondence as described by Moy, for the group $GL(\ell,F)$, where $\ell$ is prime and F is a local non-archimedean field of characteristic 0. We also prove that if one assumes a certain compatibility condition between Adler's and Howe's construction of supercuspidal representations, then the conjectural positive depth local Langlands correspondence of Reeder also agrees with the positive depth local Langlands correspondence as described by Moy, for $GL(\ell,F)$. Specifically, we first work out in detail the construction of DeBacker/Reeder for $GL(\ell,F)$, we then restate the constructions in the language of Moy, and finally prove that the correspondences agree. Up to a compatibility between Adler's and Howe's constructions, we then do the same for Reeder's positive depth construction.

math.RT↗