$f in C_{00}(mathbb{R^p},mathbb{C})$. $ mapsto f_t in L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})$...
$begingroup$
Continuing from here
Let $f_t(x):=f(x+t)$
Consider $f mapsto f_t$ which is a linear, isometric bijection from $L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})to L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})$ for every $t in mathbb{R}^p$
How can I show that for $f in C_{00}(mathbb{R^p},mathbb{C})$ (continuous and compact support) the mapping $mathbb{R}^pni t mapsto f_t in L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})$ is uniformly continuous?
real-analysis analysis lp-spaces
$endgroup$
add a comment |
$begingroup$
Continuing from here
Let $f_t(x):=f(x+t)$
Consider $f mapsto f_t$ which is a linear, isometric bijection from $L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})to L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})$ for every $t in mathbb{R}^p$
How can I show that for $f in C_{00}(mathbb{R^p},mathbb{C})$ (continuous and compact support) the mapping $mathbb{R}^pni t mapsto f_t in L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})$ is uniformly continuous?
real-analysis analysis lp-spaces
$endgroup$
add a comment |
$begingroup$
Continuing from here
Let $f_t(x):=f(x+t)$
Consider $f mapsto f_t$ which is a linear, isometric bijection from $L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})to L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})$ for every $t in mathbb{R}^p$
How can I show that for $f in C_{00}(mathbb{R^p},mathbb{C})$ (continuous and compact support) the mapping $mathbb{R}^pni t mapsto f_t in L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})$ is uniformly continuous?
real-analysis analysis lp-spaces
$endgroup$
Continuing from here
Let $f_t(x):=f(x+t)$
Consider $f mapsto f_t$ which is a linear, isometric bijection from $L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})to L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})$ for every $t in mathbb{R}^p$
How can I show that for $f in C_{00}(mathbb{R^p},mathbb{C})$ (continuous and compact support) the mapping $mathbb{R}^pni t mapsto f_t in L_infty(mathbb{R}^p, mathcal B_p, lambda_p, mathbb{C})$ is uniformly continuous?
real-analysis analysis lp-spaces
real-analysis analysis lp-spaces
asked Jan 5 at 13:56
user626880user626880
93
93
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
$begingroup$
This follows from the fact that a continuous function with compact support is uniformly continuous. For a fixed $varepsilon$, there exists $delta$ such that if $s,tinmathbb R^p$ satisfy $lVert t-srVertltdelta$, then $leftlvert f(t)-f(s)rightrvertltvarepsilon$.
For any $xinmathbb R^p$ and $s,t$ satisfying $lVert t-srVertltdelta$, the following inequality holds
$$
leftlvert f(x+t)-f(x+s)rightrvertltvarepsilon
$$
hence
$$leftlVert f_t-f_srightrVert_infty ... $$
$endgroup$
add a comment |
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%2f3062742%2ff-in-c-00-mathbbrp-mathbbc-mapsto-f-t-in-l-infty-mathbbrp%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
This follows from the fact that a continuous function with compact support is uniformly continuous. For a fixed $varepsilon$, there exists $delta$ such that if $s,tinmathbb R^p$ satisfy $lVert t-srVertltdelta$, then $leftlvert f(t)-f(s)rightrvertltvarepsilon$.
For any $xinmathbb R^p$ and $s,t$ satisfying $lVert t-srVertltdelta$, the following inequality holds
$$
leftlvert f(x+t)-f(x+s)rightrvertltvarepsilon
$$
hence
$$leftlVert f_t-f_srightrVert_infty ... $$
$endgroup$
add a comment |
$begingroup$
This follows from the fact that a continuous function with compact support is uniformly continuous. For a fixed $varepsilon$, there exists $delta$ such that if $s,tinmathbb R^p$ satisfy $lVert t-srVertltdelta$, then $leftlvert f(t)-f(s)rightrvertltvarepsilon$.
For any $xinmathbb R^p$ and $s,t$ satisfying $lVert t-srVertltdelta$, the following inequality holds
$$
leftlvert f(x+t)-f(x+s)rightrvertltvarepsilon
$$
hence
$$leftlVert f_t-f_srightrVert_infty ... $$
$endgroup$
add a comment |
$begingroup$
This follows from the fact that a continuous function with compact support is uniformly continuous. For a fixed $varepsilon$, there exists $delta$ such that if $s,tinmathbb R^p$ satisfy $lVert t-srVertltdelta$, then $leftlvert f(t)-f(s)rightrvertltvarepsilon$.
For any $xinmathbb R^p$ and $s,t$ satisfying $lVert t-srVertltdelta$, the following inequality holds
$$
leftlvert f(x+t)-f(x+s)rightrvertltvarepsilon
$$
hence
$$leftlVert f_t-f_srightrVert_infty ... $$
$endgroup$
This follows from the fact that a continuous function with compact support is uniformly continuous. For a fixed $varepsilon$, there exists $delta$ such that if $s,tinmathbb R^p$ satisfy $lVert t-srVertltdelta$, then $leftlvert f(t)-f(s)rightrvertltvarepsilon$.
For any $xinmathbb R^p$ and $s,t$ satisfying $lVert t-srVertltdelta$, the following inequality holds
$$
leftlvert f(x+t)-f(x+s)rightrvertltvarepsilon
$$
hence
$$leftlVert f_t-f_srightrVert_infty ... $$
answered Jan 5 at 14:07
Davide GiraudoDavide Giraudo
125k16150261
125k16150261
add a comment |
add a comment |
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%2f3062742%2ff-in-c-00-mathbbrp-mathbbc-mapsto-f-t-in-l-infty-mathbbrp%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