---
_id: '60993'
abstract:
- lang: eng
  text: "<p>We determine the distribution of discriminants of wildly ramified elementary-abelian
    extensions of local and global function fields in characteristic <inline-formula
    content-type=\"math/mathml\">\r\n<mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"
    alttext=\"p\">\r\n  <mml:semantics>\r\n    <mml:mi>p</mml:mi>\r\n    <mml:annotation
    encoding=\"application/x-tex\">p</mml:annotation>\r\n  </mml:semantics>\r\n</mml:math>\r\n</inline-formula>.
    For local and rational function fields, we also give precise formulae for the
    number of elementary-abelian extensions with a fixed discriminant divisor, which
    describe a local-global principle.</p>"
author:
- first_name: Nicolas
  full_name: Potthast, Nicolas
  id: '63958'
  last_name: Potthast
citation:
  ama: Potthast N. On the asymptotics of elementary-abelian extensions of local and
    global function fields. <i>Transactions of the American Mathematical Society</i>.
    2026;379(1):289-340. doi:<a href="https://doi.org/10.1090/tran/9509">10.1090/tran/9509</a>
  apa: Potthast, N. (2026). On the asymptotics of elementary-abelian extensions of
    local and global function fields. <i>Transactions of the American Mathematical
    Society</i>, <i>379</i>(1), 289–340. <a href="https://doi.org/10.1090/tran/9509">https://doi.org/10.1090/tran/9509</a>
  bibtex: '@article{Potthast_2026, title={On the asymptotics of elementary-abelian
    extensions of local and global function fields}, volume={379}, DOI={<a href="https://doi.org/10.1090/tran/9509">10.1090/tran/9509</a>},
    number={1}, journal={Transactions of the American Mathematical Society}, publisher={American
    Mathematical Society (AMS)}, author={Potthast, Nicolas}, year={2026}, pages={289–340}
    }'
  chicago: 'Potthast, Nicolas. “On the Asymptotics of Elementary-Abelian Extensions
    of Local and Global Function Fields.” <i>Transactions of the American Mathematical
    Society</i> 379, no. 1 (2026): 289–340. <a href="https://doi.org/10.1090/tran/9509">https://doi.org/10.1090/tran/9509</a>.'
  ieee: 'N. Potthast, “On the asymptotics of elementary-abelian extensions of local
    and global function fields,” <i>Transactions of the American Mathematical Society</i>,
    vol. 379, no. 1, pp. 289–340, 2026, doi: <a href="https://doi.org/10.1090/tran/9509">10.1090/tran/9509</a>.'
  mla: Potthast, Nicolas. “On the Asymptotics of Elementary-Abelian Extensions of
    Local and Global Function Fields.” <i>Transactions of the American Mathematical
    Society</i>, vol. 379, no. 1, American Mathematical Society (AMS), 2026, pp. 289–340,
    doi:<a href="https://doi.org/10.1090/tran/9509">10.1090/tran/9509</a>.
  short: N. Potthast, Transactions of the American Mathematical Society 379 (2026)
    289–340.
date_created: 2025-08-25T12:37:47Z
date_updated: 2025-12-12T08:40:53Z
doi: 10.1090/tran/9509
intvolume: '       379'
issue: '1'
language:
- iso: eng
page: 289 - 340
publication: Transactions of the American Mathematical Society
publication_identifier:
  issn:
  - 1088-6850
  - 0002-9947
publication_status: published
publisher: American Mathematical Society (AMS)
status: public
title: On the asymptotics of elementary-abelian extensions of local and global function
  fields
type: journal_article
user_id: '63958'
volume: 379
year: '2026'
...
---
_id: '53191'
abstract:
- lang: eng
  text: "<p>This paper is the first in a series of two dedicated to the study of period
    relations of the type <disp-formula content-type=\"math/mathml\">\r\n<mml:math
    xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" alttext=\"upper L left-parenthesis
    one half plus k comma normal upper Pi right-parenthesis element-of left-parenthesis
    2 pi i right-parenthesis Superscript d dot k Baseline normal upper Omega Subscript
    left-parenthesis negative 1 right-parenthesis Sub Superscript k Subscript Baseline
    reverse-solidus bf upper Q left-parenthesis normal upper Pi right-parenthesis
    comma one half plus k critical comma\">\r\n  <mml:semantics>\r\n    <mml:mrow>\r\n
    \     <mml:mi>L</mml:mi>\r\n      <mml:mstyle scriptlevel=\"0\">\r\n        <mml:mrow
    class=\"MJX-TeXAtom-ORD\">\r\n          <mml:mo maxsize=\"1.623em\" minsize=\"1.623em\">(</mml:mo>\r\n
    \       </mml:mrow>\r\n      </mml:mstyle>\r\n      <mml:mfrac>\r\n        <mml:mn>1</mml:mn>\r\n
    \       <mml:mn>2</mml:mn>\r\n      </mml:mfrac>\r\n      <mml:mo>+</mml:mo>\r\n
    \     <mml:mi>k</mml:mi>\r\n      <mml:mo>,</mml:mo>\r\n      <mml:mi mathvariant=\"normal\">Π<!--
    Π --></mml:mi>\r\n      <mml:mstyle scriptlevel=\"0\">\r\n        <mml:mrow class=\"MJX-TeXAtom-ORD\">\r\n
    \         <mml:mo maxsize=\"1.623em\" minsize=\"1.623em\">)</mml:mo>\r\n        </mml:mrow>\r\n
    \     </mml:mstyle>\r\n      <mml:mspace width=\"thickmathspace\" />\r\n      <mml:mo>∈<!--
    ∈ --></mml:mo>\r\n      <mml:mspace width=\"thickmathspace\" />\r\n      <mml:mo
    stretchy=\"false\">(</mml:mo>\r\n      <mml:mn>2</mml:mn>\r\n      <mml:mi>π<!--
    π --></mml:mi>\r\n      <mml:mi>i</mml:mi>\r\n      <mml:msup>\r\n        <mml:mo
    stretchy=\"false\">)</mml:mo>\r\n        <mml:mrow class=\"MJX-TeXAtom-ORD\">\r\n
    \         <mml:mi>d</mml:mi>\r\n          <mml:mo>⋅<!-- ⋅ --></mml:mo>\r\n          <mml:mi>k</mml:mi>\r\n
    \       </mml:mrow>\r\n      </mml:msup>\r\n      <mml:msub>\r\n        <mml:mi
    mathvariant=\"normal\">Ω<!-- Ω --></mml:mi>\r\n        <mml:mrow class=\"MJX-TeXAtom-ORD\">\r\n
    \         <mml:mo stretchy=\"false\">(</mml:mo>\r\n          <mml:mo>−<!-- − --></mml:mo>\r\n
    \         <mml:mn>1</mml:mn>\r\n          <mml:msup>\r\n            <mml:mo stretchy=\"false\">)</mml:mo>\r\n
    \           <mml:mi>k</mml:mi>\r\n          </mml:msup>\r\n        </mml:mrow>\r\n
    \     </mml:msub>\r\n      <mml:mrow class=\"MJX-TeXAtom-ORD\">\r\n        <mml:mtext>\\bf
    Q</mml:mtext>\r\n      </mml:mrow>\r\n      <mml:mo stretchy=\"false\">(</mml:mo>\r\n
    \     <mml:mi mathvariant=\"normal\">Π<!-- Π --></mml:mi>\r\n      <mml:mo stretchy=\"false\">)</mml:mo>\r\n
    \     <mml:mo>,</mml:mo>\r\n      <mml:mspace width=\"1em\" />\r\n      <mml:mfrac>\r\n
    \       <mml:mn>1</mml:mn>\r\n        <mml:mn>2</mml:mn>\r\n      </mml:mfrac>\r\n
    \     <mml:mo>+</mml:mo>\r\n      <mml:mi>k</mml:mi>\r\n      <mml:mspace width=\"thickmathspace\"
    />\r\n      <mml:mtext>critical</mml:mtext>\r\n      <mml:mo>,</mml:mo>\r\n    </mml:mrow>\r\n
    \   <mml:annotation encoding=\"application/x-tex\">\\begin{equation*} L\\Big (\\frac
    {1}{2}+k,\\Pi \\Big )\\;\\in \\;(2\\pi i)^{d\\cdot k}\\Omega _{(-1)^k}\\textrm
    {\\bf Q}(\\Pi ),\\quad \\frac {1}{2}+k\\;\\text {critical}, \\end{equation*}</mml:annotation>\r\n
    \ </mml:semantics>\r\n</mml:math>\r\n</disp-formula>\r\n for certain automorphic
    representations <inline-formula content-type=\"math/mathml\">\r\n<mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"
    alttext=\"normal upper Pi\">\r\n  <mml:semantics>\r\n    <mml:mi mathvariant=\"normal\">Π<!--
    Π --></mml:mi>\r\n    <mml:annotation encoding=\"application/x-tex\">\\Pi</mml:annotation>\r\n
    \ </mml:semantics>\r\n</mml:math>\r\n</inline-formula> of a reductive group <inline-formula
    content-type=\"math/mathml\">\r\n<mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"
    alttext=\"upper G period\">\r\n  <mml:semantics>\r\n    <mml:mrow>\r\n      <mml:mi>G</mml:mi>\r\n
    \     <mml:mo>.</mml:mo>\r\n    </mml:mrow>\r\n    <mml:annotation encoding=\"application/x-tex\">G.</mml:annotation>\r\n
    \ </mml:semantics>\r\n</mml:math>\r\n</inline-formula> In this paper we discuss
    the case <inline-formula content-type=\"math/mathml\">\r\n<mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"
    alttext=\"upper G equals normal upper G normal upper L left-parenthesis n plus
    1 right-parenthesis times normal upper G normal upper L left-parenthesis n right-parenthesis
    period\">\r\n  <mml:semantics>\r\n    <mml:mrow>\r\n      <mml:mi>G</mml:mi>\r\n
    \     <mml:mo>=</mml:mo>\r\n      <mml:mrow class=\"MJX-TeXAtom-ORD\">\r\n        <mml:mi
    mathvariant=\"normal\">G</mml:mi>\r\n        <mml:mi mathvariant=\"normal\">L</mml:mi>\r\n
    \     </mml:mrow>\r\n      <mml:mo stretchy=\"false\">(</mml:mo>\r\n      <mml:mi>n</mml:mi>\r\n
    \     <mml:mo>+</mml:mo>\r\n      <mml:mn>1</mml:mn>\r\n      <mml:mo stretchy=\"false\">)</mml:mo>\r\n
    \     <mml:mo>×<!-- × --></mml:mo>\r\n      <mml:mrow class=\"MJX-TeXAtom-ORD\">\r\n
    \       <mml:mi mathvariant=\"normal\">G</mml:mi>\r\n        <mml:mi mathvariant=\"normal\">L</mml:mi>\r\n
    \     </mml:mrow>\r\n      <mml:mo stretchy=\"false\">(</mml:mo>\r\n      <mml:mi>n</mml:mi>\r\n
    \     <mml:mo stretchy=\"false\">)</mml:mo>\r\n      <mml:mo>.</mml:mo>\r\n    </mml:mrow>\r\n
    \   <mml:annotation encoding=\"application/x-tex\">G=\\mathrm {GL}(n+1)\\times
    \\mathrm {GL}(n).</mml:annotation>\r\n  </mml:semantics>\r\n</mml:math>\r\n</inline-formula>
    The case <inline-formula content-type=\"math/mathml\">\r\n<mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\"
    alttext=\"upper G equals normal upper G normal upper L left-parenthesis 2 n right-parenthesis\">\r\n
    \ <mml:semantics>\r\n    <mml:mrow>\r\n      <mml:mi>G</mml:mi>\r\n      <mml:mo>=</mml:mo>\r\n
    \     <mml:mrow class=\"MJX-TeXAtom-ORD\">\r\n        <mml:mi mathvariant=\"normal\">G</mml:mi>\r\n
    \       <mml:mi mathvariant=\"normal\">L</mml:mi>\r\n      </mml:mrow>\r\n      <mml:mo
    stretchy=\"false\">(</mml:mo>\r\n      <mml:mn>2</mml:mn>\r\n      <mml:mi>n</mml:mi>\r\n
    \     <mml:mo stretchy=\"false\">)</mml:mo>\r\n    </mml:mrow>\r\n    <mml:annotation
    encoding=\"application/x-tex\">G=\\mathrm {GL}(2n)</mml:annotation>\r\n  </mml:semantics>\r\n</mml:math>\r\n</inline-formula>
    is discussed in part two. Our method is representation theoretic and relies on
    the author’s recent results on global rational structures on automorphic representations.
    We show that the above period relations are intimately related to the field of
    definition of the global representation <inline-formula content-type=\"math/mathml\">\r\n<mml:math
    xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" alttext=\"normal upper Pi\">\r\n
    \ <mml:semantics>\r\n    <mml:mi mathvariant=\"normal\">Π<!-- Π --></mml:mi>\r\n
    \   <mml:annotation encoding=\"application/x-tex\">\\Pi</mml:annotation>\r\n  </mml:semantics>\r\n</mml:math>\r\n</inline-formula>
    under consideration. The new period relations we prove are in accordance with
    Deligne’s Conjecture on special values of <inline-formula content-type=\"math/mathml\">\r\n<mml:math
    xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" alttext=\"upper L\">\r\n  <mml:semantics>\r\n
    \   <mml:mi>L</mml:mi>\r\n    <mml:annotation encoding=\"application/x-tex\">L</mml:annotation>\r\n
    \ </mml:semantics>\r\n</mml:math>\r\n</inline-formula>-functions, and the author
    expects this method to apply to other cases as well.</p>"
article_type: original
author:
- first_name: Fabian
  full_name: Januszewski, Fabian
  id: '81636'
  last_name: Januszewski
  orcid: 0000-0002-3184-237X
citation:
  ama: "Januszewski F. On period relations for automorphic \U0001D43F-functions I.
    <i>Transactions of the American Mathematical Society</i>. 2018;371(9):6547-6580.
    doi:<a href=\"https://doi.org/10.1090/tran/7527\">10.1090/tran/7527</a>"
  apa: "Januszewski, F. (2018). On period relations for automorphic \U0001D43F-functions
    I. <i>Transactions of the American Mathematical Society</i>, <i>371</i>(9), 6547–6580.
    <a href=\"https://doi.org/10.1090/tran/7527\">https://doi.org/10.1090/tran/7527</a>"
  bibtex: "@article{Januszewski_2018, title={On period relations for automorphic \U0001D43F-functions
    I}, volume={371}, DOI={<a href=\"https://doi.org/10.1090/tran/7527\">10.1090/tran/7527</a>},
    number={9}, journal={Transactions of the American Mathematical Society}, publisher={American
    Mathematical Society (AMS)}, author={Januszewski, Fabian}, year={2018}, pages={6547–6580}
    }"
  chicago: "Januszewski, Fabian. “On Period Relations for Automorphic \U0001D43F-Functions
    I.” <i>Transactions of the American Mathematical Society</i> 371, no. 9 (2018):
    6547–80. <a href=\"https://doi.org/10.1090/tran/7527\">https://doi.org/10.1090/tran/7527</a>."
  ieee: "F. Januszewski, “On period relations for automorphic \U0001D43F-functions
    I,” <i>Transactions of the American Mathematical Society</i>, vol. 371, no. 9,
    pp. 6547–6580, 2018, doi: <a href=\"https://doi.org/10.1090/tran/7527\">10.1090/tran/7527</a>."
  mla: "Januszewski, Fabian. “On Period Relations for Automorphic \U0001D43F-Functions
    I.” <i>Transactions of the American Mathematical Society</i>, vol. 371, no. 9,
    American Mathematical Society (AMS), 2018, pp. 6547–80, doi:<a href=\"https://doi.org/10.1090/tran/7527\">10.1090/tran/7527</a>."
  short: F. Januszewski, Transactions of the American Mathematical Society 371 (2018)
    6547–6580.
date_created: 2024-04-03T16:58:26Z
date_updated: 2024-04-03T17:26:38Z
doi: 10.1090/tran/7527
extern: '1'
intvolume: '       371'
issue: '9'
keyword:
- Applied Mathematics
- General Mathematics
language:
- iso: eng
page: 6547-6580
publication: Transactions of the American Mathematical Society
publication_identifier:
  issn:
  - 0002-9947
  - 1088-6850
publication_status: published
publisher: American Mathematical Society (AMS)
status: public
title: "On period relations for automorphic \U0001D43F-functions I"
type: journal_article
user_id: '81636'
volume: 371
year: '2018'
...
---
_id: '38032'
author:
- first_name: Margit
  full_name: Rösler, Margit
  id: '37390'
  last_name: Rösler
- first_name: Michael
  full_name: Voit, Michael
  last_name: Voit
citation:
  ama: Rösler M, Voit M. Integral representation and sharp asymptotic results for
    some Heckman-Opdam hypergeometric functions of type BC. <i>Transactions of the
    American Mathematical Society</i>. 2016;368(8):6005-6032. doi:<a href="https://doi.org/10.48550/ARXIV.1402.5793">10.48550/ARXIV.1402.5793</a>
  apa: Rösler, M., &#38; Voit, M. (2016). Integral representation and sharp asymptotic
    results for some Heckman-Opdam hypergeometric functions of type BC. <i>Transactions
    of the American Mathematical Society</i>, <i>368</i>(8), 6005–6032. <a href="https://doi.org/10.48550/ARXIV.1402.5793">https://doi.org/10.48550/ARXIV.1402.5793</a>
  bibtex: '@article{Rösler_Voit_2016, title={Integral representation and sharp asymptotic
    results for some Heckman-Opdam hypergeometric functions of type BC}, volume={368},
    DOI={<a href="https://doi.org/10.48550/ARXIV.1402.5793">10.48550/ARXIV.1402.5793</a>},
    number={8}, journal={Transactions of the American Mathematical Society}, publisher={
    American Mathematical Society}, author={Rösler, Margit and Voit, Michael}, year={2016},
    pages={6005–6032} }'
  chicago: 'Rösler, Margit, and Michael Voit. “Integral Representation and Sharp Asymptotic
    Results for Some Heckman-Opdam Hypergeometric Functions of Type BC.” <i>Transactions
    of the American Mathematical Society</i> 368, no. 8 (2016): 6005–32. <a href="https://doi.org/10.48550/ARXIV.1402.5793">https://doi.org/10.48550/ARXIV.1402.5793</a>.'
  ieee: 'M. Rösler and M. Voit, “Integral representation and sharp asymptotic results
    for some Heckman-Opdam hypergeometric functions of type BC,” <i>Transactions of
    the American Mathematical Society</i>, vol. 368, no. 8, pp. 6005–6032, 2016, doi:
    <a href="https://doi.org/10.48550/ARXIV.1402.5793">10.48550/ARXIV.1402.5793</a>.'
  mla: Rösler, Margit, and Michael Voit. “Integral Representation and Sharp Asymptotic
    Results for Some Heckman-Opdam Hypergeometric Functions of Type BC.” <i>Transactions
    of the American Mathematical Society</i>, vol. 368, no. 8,  American Mathematical
    Society, 2016, pp. 6005–32, doi:<a href="https://doi.org/10.48550/ARXIV.1402.5793">10.48550/ARXIV.1402.5793</a>.
  short: M. Rösler, M. Voit, Transactions of the American Mathematical Society 368
    (2016) 6005–6032.
date_created: 2023-01-23T08:09:20Z
date_updated: 2023-01-24T22:15:46Z
department:
- _id: '555'
doi: 10.48550/ARXIV.1402.5793
intvolume: '       368'
issue: '8'
language:
- iso: eng
page: 6005-6032
publication: Transactions of the American Mathematical Society
publication_identifier:
  issn:
  - 1088-6850
publication_status: published
publisher: ' American Mathematical Society'
status: public
title: Integral representation and sharp asymptotic results for some Heckman-Opdam
  hypergeometric functions of type BC
type: journal_article
user_id: '37390'
volume: 368
year: '2016'
...
