The characters of the generalized Steinberg representations of finite general linear groups on the regular elliptic set

Authors:
Allan J. Silberger and Ernst-Wilhelm Zink

Journal:
Trans. Amer. Math. Soc. **352** (2000), 3339-3356

MSC (1991):
Primary 22E50, 11T24

DOI:
https://doi.org/10.1090/S0002-9947-00-02454-5

Published electronically:
March 24, 2000

MathSciNet review:
1650042

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Abstract: Let be a finite field, the degree extension of , and the general linear group with entries in . This paper studies the ``generalized Steinberg" (GS) representations of and proves the equivalence of several different characterizations for this class of representations. As our main result we show that the union of the class of cuspidal and GS representations of is in natural one-one correspondence with the set of Galois orbits of characters of , the regular orbits of course corresponding to the cuspidal representations. Besides using Green's character formulas to define GS representations, we characterize GS representations by associating to them idempotents in certain commuting algebras corresponding to parabolic inductions and by showing that GS representations are the sole components of these induced representations which are ``generic" (have Whittaker vectors).

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Additional Information

**Allan J. Silberger**

Affiliation:
Department of Mathematics, Cleveland State University, Cleveland, Ohio 44115

Email:
silberger@math.csuohio.edu

**Ernst-Wilhelm Zink**

Affiliation:
Humboldt-Universität, FB Reine Mathematik, Unter den Linden 6, 10099 Berlin, Germany

Email:
zink@mathematik.hu-berlin.de

DOI:
https://doi.org/10.1090/S0002-9947-00-02454-5

Keywords:
Reductive group,
general linear group,
finite field,
character,
unitary representation,
Steinberg representation,
Whittaker vector,
generic representation

Received by editor(s):
May 26, 1997

Received by editor(s) in revised form:
April 18, 1998, and June 26, 1998

Published electronically:
March 24, 2000

Article copyright:
© Copyright 2000
American Mathematical Society