Matrix coefficients of Supercuspidal representations
$begingroup$
Let $F$ be a finite extension of the $p$-adic field $mathbb{Q}_p$, and let $(pi,V)$ be a supercuspidal representation of $G=GL_n(F)$. In particular, all its matrix coefficients have compact support modulo the center $Z$ of $G$. I want to prove that for every matrix coefficient $phi: G to mathbb{C}$ and every parabolic subgroup $P=MN$ (where $N$ is the unipotent radical of $P$) and every $g in G$, the integral
$$int_N phi(gn)dn = 0$$
Here is my attempt so far: Since $(pi,V)$ is supercuspidal, its Jacquet module $V_{N}$ if trivial for $N$ that arises from every possible parabolic subgroup. Thus, $V=V(N)$, or in other words, any vector in $V$ is expressible as a finite linear combination of vectors of the form $pi(n) v - v $ for some $n in N$ and $v in V$.
Now suppose the matrix coefficient $phi$ corresponds to the vector $w in V$ and $lambda in V^{*}$ so that
$$phi(gn)=lambda ( pi(gn)w)$$
In this case
$$int_N phi(gn)dn = int_N lambda(pi(g)pi(n) w) dn$$
Since $w$ is a finite linear combination of elements of the form $pi(n')v-v$, the above reduces to a sum of integrals of the form
$$int_N lambda( pi(g) pi(n)left(pi(n')v-vright)) dn= int_N lambda(pi(gnn')v)dn - int_N lambda(pi(gn)v)dn$$
But is the above expression $0$?
representation-theory lie-groups p-adic-number-theory
$endgroup$
add a comment |
$begingroup$
Let $F$ be a finite extension of the $p$-adic field $mathbb{Q}_p$, and let $(pi,V)$ be a supercuspidal representation of $G=GL_n(F)$. In particular, all its matrix coefficients have compact support modulo the center $Z$ of $G$. I want to prove that for every matrix coefficient $phi: G to mathbb{C}$ and every parabolic subgroup $P=MN$ (where $N$ is the unipotent radical of $P$) and every $g in G$, the integral
$$int_N phi(gn)dn = 0$$
Here is my attempt so far: Since $(pi,V)$ is supercuspidal, its Jacquet module $V_{N}$ if trivial for $N$ that arises from every possible parabolic subgroup. Thus, $V=V(N)$, or in other words, any vector in $V$ is expressible as a finite linear combination of vectors of the form $pi(n) v - v $ for some $n in N$ and $v in V$.
Now suppose the matrix coefficient $phi$ corresponds to the vector $w in V$ and $lambda in V^{*}$ so that
$$phi(gn)=lambda ( pi(gn)w)$$
In this case
$$int_N phi(gn)dn = int_N lambda(pi(g)pi(n) w) dn$$
Since $w$ is a finite linear combination of elements of the form $pi(n')v-v$, the above reduces to a sum of integrals of the form
$$int_N lambda( pi(g) pi(n)left(pi(n')v-vright)) dn= int_N lambda(pi(gnn')v)dn - int_N lambda(pi(gn)v)dn$$
But is the above expression $0$?
representation-theory lie-groups p-adic-number-theory
$endgroup$
$begingroup$
Yes (use translation invariance of $dn$ to justify deleting $n'$ from the first term of the RHS).
$endgroup$
– Oven
Jan 27 at 15:02
add a comment |
$begingroup$
Let $F$ be a finite extension of the $p$-adic field $mathbb{Q}_p$, and let $(pi,V)$ be a supercuspidal representation of $G=GL_n(F)$. In particular, all its matrix coefficients have compact support modulo the center $Z$ of $G$. I want to prove that for every matrix coefficient $phi: G to mathbb{C}$ and every parabolic subgroup $P=MN$ (where $N$ is the unipotent radical of $P$) and every $g in G$, the integral
$$int_N phi(gn)dn = 0$$
Here is my attempt so far: Since $(pi,V)$ is supercuspidal, its Jacquet module $V_{N}$ if trivial for $N$ that arises from every possible parabolic subgroup. Thus, $V=V(N)$, or in other words, any vector in $V$ is expressible as a finite linear combination of vectors of the form $pi(n) v - v $ for some $n in N$ and $v in V$.
Now suppose the matrix coefficient $phi$ corresponds to the vector $w in V$ and $lambda in V^{*}$ so that
$$phi(gn)=lambda ( pi(gn)w)$$
In this case
$$int_N phi(gn)dn = int_N lambda(pi(g)pi(n) w) dn$$
Since $w$ is a finite linear combination of elements of the form $pi(n')v-v$, the above reduces to a sum of integrals of the form
$$int_N lambda( pi(g) pi(n)left(pi(n')v-vright)) dn= int_N lambda(pi(gnn')v)dn - int_N lambda(pi(gn)v)dn$$
But is the above expression $0$?
representation-theory lie-groups p-adic-number-theory
$endgroup$
Let $F$ be a finite extension of the $p$-adic field $mathbb{Q}_p$, and let $(pi,V)$ be a supercuspidal representation of $G=GL_n(F)$. In particular, all its matrix coefficients have compact support modulo the center $Z$ of $G$. I want to prove that for every matrix coefficient $phi: G to mathbb{C}$ and every parabolic subgroup $P=MN$ (where $N$ is the unipotent radical of $P$) and every $g in G$, the integral
$$int_N phi(gn)dn = 0$$
Here is my attempt so far: Since $(pi,V)$ is supercuspidal, its Jacquet module $V_{N}$ if trivial for $N$ that arises from every possible parabolic subgroup. Thus, $V=V(N)$, or in other words, any vector in $V$ is expressible as a finite linear combination of vectors of the form $pi(n) v - v $ for some $n in N$ and $v in V$.
Now suppose the matrix coefficient $phi$ corresponds to the vector $w in V$ and $lambda in V^{*}$ so that
$$phi(gn)=lambda ( pi(gn)w)$$
In this case
$$int_N phi(gn)dn = int_N lambda(pi(g)pi(n) w) dn$$
Since $w$ is a finite linear combination of elements of the form $pi(n')v-v$, the above reduces to a sum of integrals of the form
$$int_N lambda( pi(g) pi(n)left(pi(n')v-vright)) dn= int_N lambda(pi(gnn')v)dn - int_N lambda(pi(gn)v)dn$$
But is the above expression $0$?
representation-theory lie-groups p-adic-number-theory
representation-theory lie-groups p-adic-number-theory
asked Jan 26 at 16:45
BharatRamBharatRam
925619
925619
$begingroup$
Yes (use translation invariance of $dn$ to justify deleting $n'$ from the first term of the RHS).
$endgroup$
– Oven
Jan 27 at 15:02
add a comment |
$begingroup$
Yes (use translation invariance of $dn$ to justify deleting $n'$ from the first term of the RHS).
$endgroup$
– Oven
Jan 27 at 15:02
$begingroup$
Yes (use translation invariance of $dn$ to justify deleting $n'$ from the first term of the RHS).
$endgroup$
– Oven
Jan 27 at 15:02
$begingroup$
Yes (use translation invariance of $dn$ to justify deleting $n'$ from the first term of the RHS).
$endgroup$
– Oven
Jan 27 at 15:02
add a comment |
0
active
oldest
votes
Your Answer
StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "69"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3088469%2fmatrix-coefficients-of-supercuspidal-representations%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
0
active
oldest
votes
0
active
oldest
votes
active
oldest
votes
active
oldest
votes
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3088469%2fmatrix-coefficients-of-supercuspidal-representations%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
$begingroup$
Yes (use translation invariance of $dn$ to justify deleting $n'$ from the first term of the RHS).
$endgroup$
– Oven
Jan 27 at 15:02