Fast inversion over large finite fields
$begingroup$
I was wondering if there is a "fastest" way to compute inversions over finite fields, especially if they are very large. I know that the standard way is the extended Euclidean algorithm, which runs in $O(log^2p)$, with $p$ being the characteristic of the finite field. In my case, $p=2^u3^vpm 1$ a very large prime. Is there a way to compute $a^{-1}text{ mod } p$ faster than with the Euclidean algorithm, in general, or maybe by somehow using the structure of the characteristic to our advantage?
Thank you for any help!
finite-fields computational-complexity
$endgroup$
add a comment |
$begingroup$
I was wondering if there is a "fastest" way to compute inversions over finite fields, especially if they are very large. I know that the standard way is the extended Euclidean algorithm, which runs in $O(log^2p)$, with $p$ being the characteristic of the finite field. In my case, $p=2^u3^vpm 1$ a very large prime. Is there a way to compute $a^{-1}text{ mod } p$ faster than with the Euclidean algorithm, in general, or maybe by somehow using the structure of the characteristic to our advantage?
Thank you for any help!
finite-fields computational-complexity
$endgroup$
1
$begingroup$
I'm not an expert on this so I cannot say for sure, but... have you checked out the potential of using Montgomery representatives? One of the first hits to the buzzword Montgomery inverse.
$endgroup$
– Jyrki Lahtonen
Jan 21 at 14:52
add a comment |
$begingroup$
I was wondering if there is a "fastest" way to compute inversions over finite fields, especially if they are very large. I know that the standard way is the extended Euclidean algorithm, which runs in $O(log^2p)$, with $p$ being the characteristic of the finite field. In my case, $p=2^u3^vpm 1$ a very large prime. Is there a way to compute $a^{-1}text{ mod } p$ faster than with the Euclidean algorithm, in general, or maybe by somehow using the structure of the characteristic to our advantage?
Thank you for any help!
finite-fields computational-complexity
$endgroup$
I was wondering if there is a "fastest" way to compute inversions over finite fields, especially if they are very large. I know that the standard way is the extended Euclidean algorithm, which runs in $O(log^2p)$, with $p$ being the characteristic of the finite field. In my case, $p=2^u3^vpm 1$ a very large prime. Is there a way to compute $a^{-1}text{ mod } p$ faster than with the Euclidean algorithm, in general, or maybe by somehow using the structure of the characteristic to our advantage?
Thank you for any help!
finite-fields computational-complexity
finite-fields computational-complexity
asked Jan 21 at 11:00
GemeisGemeis
133
133
1
$begingroup$
I'm not an expert on this so I cannot say for sure, but... have you checked out the potential of using Montgomery representatives? One of the first hits to the buzzword Montgomery inverse.
$endgroup$
– Jyrki Lahtonen
Jan 21 at 14:52
add a comment |
1
$begingroup$
I'm not an expert on this so I cannot say for sure, but... have you checked out the potential of using Montgomery representatives? One of the first hits to the buzzword Montgomery inverse.
$endgroup$
– Jyrki Lahtonen
Jan 21 at 14:52
1
1
$begingroup$
I'm not an expert on this so I cannot say for sure, but... have you checked out the potential of using Montgomery representatives? One of the first hits to the buzzword Montgomery inverse.
$endgroup$
– Jyrki Lahtonen
Jan 21 at 14:52
$begingroup$
I'm not an expert on this so I cannot say for sure, but... have you checked out the potential of using Montgomery representatives? One of the first hits to the buzzword Montgomery inverse.
$endgroup$
– Jyrki Lahtonen
Jan 21 at 14:52
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%2f3081742%2ffast-inversion-over-large-finite-fields%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%2f3081742%2ffast-inversion-over-large-finite-fields%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
1
$begingroup$
I'm not an expert on this so I cannot say for sure, but... have you checked out the potential of using Montgomery representatives? One of the first hits to the buzzword Montgomery inverse.
$endgroup$
– Jyrki Lahtonen
Jan 21 at 14:52