$n$th power residue conjecture
Let $left(dfrac{a}{p}right)_n$ be the $n$th power residue symbol such that when $a$ is an $n$th power residue $pmod p$, $left(dfrac{a}{p}right)_n=1$ otherwise $left(dfrac{a}{p}right)_n=zeta$. Let $f_n(x)$ be a defining polynomial for the $n$th cyclotomic field $K=mathbb{Q}(e^{2pi i/n})$. Suppose that there exists some integer $m$ such that $f_n(m)=0 pmod {n^2}$, and there are primes $p$ and $q$ such that $p=f_n(z)$ and $q=f_n(z+a)$. Then $left(dfrac{a}{p}right)_n = left(dfrac{a}{q}right)_n$. When $n=3$, this conjecture agrees with cubic reciprocity theorems. The same is true for $n=4$.
Here is an example of the conjecture for $n=5$:
$f_5(x)=x^4+5x^3+10x^2+25$ and $f_5(0)=0pmod {5^2}$
$a=3$, $p=f_5(1)=41$ and $q=f_5(1+a)=f_5(4)=761$ are both prime, thus
$left(dfrac{3}{41}right)_5 = left(dfrac{3}{761}right)_5$.
Since $3$ is a quintic residue $pmod {41}$, then it is also a quintic residue of $761$. In general, if $p=f_5(3a+1)$ is prime, then $3$ is a quintic residue $pmod p$.
elementary-number-theory cubic-reciprocity
add a comment |
Let $left(dfrac{a}{p}right)_n$ be the $n$th power residue symbol such that when $a$ is an $n$th power residue $pmod p$, $left(dfrac{a}{p}right)_n=1$ otherwise $left(dfrac{a}{p}right)_n=zeta$. Let $f_n(x)$ be a defining polynomial for the $n$th cyclotomic field $K=mathbb{Q}(e^{2pi i/n})$. Suppose that there exists some integer $m$ such that $f_n(m)=0 pmod {n^2}$, and there are primes $p$ and $q$ such that $p=f_n(z)$ and $q=f_n(z+a)$. Then $left(dfrac{a}{p}right)_n = left(dfrac{a}{q}right)_n$. When $n=3$, this conjecture agrees with cubic reciprocity theorems. The same is true for $n=4$.
Here is an example of the conjecture for $n=5$:
$f_5(x)=x^4+5x^3+10x^2+25$ and $f_5(0)=0pmod {5^2}$
$a=3$, $p=f_5(1)=41$ and $q=f_5(1+a)=f_5(4)=761$ are both prime, thus
$left(dfrac{3}{41}right)_5 = left(dfrac{3}{761}right)_5$.
Since $3$ is a quintic residue $pmod {41}$, then it is also a quintic residue of $761$. In general, if $p=f_5(3a+1)$ is prime, then $3$ is a quintic residue $pmod p$.
elementary-number-theory cubic-reciprocity
2
Your $n$-th power residue symbol is not standard when $n > 2$: its value at numbers that are not $n$th powers mod $p$ should not be $-1$, but some $n$th root of unity if you want the symbol to be multiplicative in any reasonable way. Also, using ordinary prime numbers rather than prime ideals in $mathbf Z[e^{2pi i/n}]$ seems unusual, e.g., cubic reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/3}]$ and quartic (biquadratic) reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/4}] = mathbf Z[i]$. Your conjecture has a gap: what type of number is $z$?
– KCd
Nov 20 '18 at 23:51
@KCd changing -1 to a root of unity is only nessesary when dealing with cosets of the groups of $n$th power residues but I changed it anyways. As for $z$, like $x, a,$ and $n$ is an integer.
– J. Linne
Nov 21 '18 at 7:32
For $n > 2$, an $n$th power residue symbol does not just have two nonzero values, "1 and $zeta$". Its nonzero values run over all $n$th roots of unity, in order to be multiplicative in $a$, so your description of $(frac{a}{p})_n$ is unusual (esp. since $p$ need not be prime in $mathbf Z[e^{2pi i/n}]$, e.g., $p = 41$ when $n = 5$. Where are you getting your description of power residue symbols from?
– KCd
Nov 21 '18 at 11:24
@KCd In theory, yes your assertion is correct, but here we only care about the solvability of $a=x^n pmod p$, and there is only two "values". Solvable $(1)$ or non-solvable $(-1)$ or a particular root of unity.
– J. Linne
Nov 24 '18 at 1:46
add a comment |
Let $left(dfrac{a}{p}right)_n$ be the $n$th power residue symbol such that when $a$ is an $n$th power residue $pmod p$, $left(dfrac{a}{p}right)_n=1$ otherwise $left(dfrac{a}{p}right)_n=zeta$. Let $f_n(x)$ be a defining polynomial for the $n$th cyclotomic field $K=mathbb{Q}(e^{2pi i/n})$. Suppose that there exists some integer $m$ such that $f_n(m)=0 pmod {n^2}$, and there are primes $p$ and $q$ such that $p=f_n(z)$ and $q=f_n(z+a)$. Then $left(dfrac{a}{p}right)_n = left(dfrac{a}{q}right)_n$. When $n=3$, this conjecture agrees with cubic reciprocity theorems. The same is true for $n=4$.
Here is an example of the conjecture for $n=5$:
$f_5(x)=x^4+5x^3+10x^2+25$ and $f_5(0)=0pmod {5^2}$
$a=3$, $p=f_5(1)=41$ and $q=f_5(1+a)=f_5(4)=761$ are both prime, thus
$left(dfrac{3}{41}right)_5 = left(dfrac{3}{761}right)_5$.
Since $3$ is a quintic residue $pmod {41}$, then it is also a quintic residue of $761$. In general, if $p=f_5(3a+1)$ is prime, then $3$ is a quintic residue $pmod p$.
elementary-number-theory cubic-reciprocity
Let $left(dfrac{a}{p}right)_n$ be the $n$th power residue symbol such that when $a$ is an $n$th power residue $pmod p$, $left(dfrac{a}{p}right)_n=1$ otherwise $left(dfrac{a}{p}right)_n=zeta$. Let $f_n(x)$ be a defining polynomial for the $n$th cyclotomic field $K=mathbb{Q}(e^{2pi i/n})$. Suppose that there exists some integer $m$ such that $f_n(m)=0 pmod {n^2}$, and there are primes $p$ and $q$ such that $p=f_n(z)$ and $q=f_n(z+a)$. Then $left(dfrac{a}{p}right)_n = left(dfrac{a}{q}right)_n$. When $n=3$, this conjecture agrees with cubic reciprocity theorems. The same is true for $n=4$.
Here is an example of the conjecture for $n=5$:
$f_5(x)=x^4+5x^3+10x^2+25$ and $f_5(0)=0pmod {5^2}$
$a=3$, $p=f_5(1)=41$ and $q=f_5(1+a)=f_5(4)=761$ are both prime, thus
$left(dfrac{3}{41}right)_5 = left(dfrac{3}{761}right)_5$.
Since $3$ is a quintic residue $pmod {41}$, then it is also a quintic residue of $761$. In general, if $p=f_5(3a+1)$ is prime, then $3$ is a quintic residue $pmod p$.
elementary-number-theory cubic-reciprocity
elementary-number-theory cubic-reciprocity
edited Nov 21 '18 at 7:29
asked Nov 20 '18 at 1:40
J. Linne
846315
846315
2
Your $n$-th power residue symbol is not standard when $n > 2$: its value at numbers that are not $n$th powers mod $p$ should not be $-1$, but some $n$th root of unity if you want the symbol to be multiplicative in any reasonable way. Also, using ordinary prime numbers rather than prime ideals in $mathbf Z[e^{2pi i/n}]$ seems unusual, e.g., cubic reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/3}]$ and quartic (biquadratic) reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/4}] = mathbf Z[i]$. Your conjecture has a gap: what type of number is $z$?
– KCd
Nov 20 '18 at 23:51
@KCd changing -1 to a root of unity is only nessesary when dealing with cosets of the groups of $n$th power residues but I changed it anyways. As for $z$, like $x, a,$ and $n$ is an integer.
– J. Linne
Nov 21 '18 at 7:32
For $n > 2$, an $n$th power residue symbol does not just have two nonzero values, "1 and $zeta$". Its nonzero values run over all $n$th roots of unity, in order to be multiplicative in $a$, so your description of $(frac{a}{p})_n$ is unusual (esp. since $p$ need not be prime in $mathbf Z[e^{2pi i/n}]$, e.g., $p = 41$ when $n = 5$. Where are you getting your description of power residue symbols from?
– KCd
Nov 21 '18 at 11:24
@KCd In theory, yes your assertion is correct, but here we only care about the solvability of $a=x^n pmod p$, and there is only two "values". Solvable $(1)$ or non-solvable $(-1)$ or a particular root of unity.
– J. Linne
Nov 24 '18 at 1:46
add a comment |
2
Your $n$-th power residue symbol is not standard when $n > 2$: its value at numbers that are not $n$th powers mod $p$ should not be $-1$, but some $n$th root of unity if you want the symbol to be multiplicative in any reasonable way. Also, using ordinary prime numbers rather than prime ideals in $mathbf Z[e^{2pi i/n}]$ seems unusual, e.g., cubic reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/3}]$ and quartic (biquadratic) reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/4}] = mathbf Z[i]$. Your conjecture has a gap: what type of number is $z$?
– KCd
Nov 20 '18 at 23:51
@KCd changing -1 to a root of unity is only nessesary when dealing with cosets of the groups of $n$th power residues but I changed it anyways. As for $z$, like $x, a,$ and $n$ is an integer.
– J. Linne
Nov 21 '18 at 7:32
For $n > 2$, an $n$th power residue symbol does not just have two nonzero values, "1 and $zeta$". Its nonzero values run over all $n$th roots of unity, in order to be multiplicative in $a$, so your description of $(frac{a}{p})_n$ is unusual (esp. since $p$ need not be prime in $mathbf Z[e^{2pi i/n}]$, e.g., $p = 41$ when $n = 5$. Where are you getting your description of power residue symbols from?
– KCd
Nov 21 '18 at 11:24
@KCd In theory, yes your assertion is correct, but here we only care about the solvability of $a=x^n pmod p$, and there is only two "values". Solvable $(1)$ or non-solvable $(-1)$ or a particular root of unity.
– J. Linne
Nov 24 '18 at 1:46
2
2
Your $n$-th power residue symbol is not standard when $n > 2$: its value at numbers that are not $n$th powers mod $p$ should not be $-1$, but some $n$th root of unity if you want the symbol to be multiplicative in any reasonable way. Also, using ordinary prime numbers rather than prime ideals in $mathbf Z[e^{2pi i/n}]$ seems unusual, e.g., cubic reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/3}]$ and quartic (biquadratic) reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/4}] = mathbf Z[i]$. Your conjecture has a gap: what type of number is $z$?
– KCd
Nov 20 '18 at 23:51
Your $n$-th power residue symbol is not standard when $n > 2$: its value at numbers that are not $n$th powers mod $p$ should not be $-1$, but some $n$th root of unity if you want the symbol to be multiplicative in any reasonable way. Also, using ordinary prime numbers rather than prime ideals in $mathbf Z[e^{2pi i/n}]$ seems unusual, e.g., cubic reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/3}]$ and quartic (biquadratic) reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/4}] = mathbf Z[i]$. Your conjecture has a gap: what type of number is $z$?
– KCd
Nov 20 '18 at 23:51
@KCd changing -1 to a root of unity is only nessesary when dealing with cosets of the groups of $n$th power residues but I changed it anyways. As for $z$, like $x, a,$ and $n$ is an integer.
– J. Linne
Nov 21 '18 at 7:32
@KCd changing -1 to a root of unity is only nessesary when dealing with cosets of the groups of $n$th power residues but I changed it anyways. As for $z$, like $x, a,$ and $n$ is an integer.
– J. Linne
Nov 21 '18 at 7:32
For $n > 2$, an $n$th power residue symbol does not just have two nonzero values, "1 and $zeta$". Its nonzero values run over all $n$th roots of unity, in order to be multiplicative in $a$, so your description of $(frac{a}{p})_n$ is unusual (esp. since $p$ need not be prime in $mathbf Z[e^{2pi i/n}]$, e.g., $p = 41$ when $n = 5$. Where are you getting your description of power residue symbols from?
– KCd
Nov 21 '18 at 11:24
For $n > 2$, an $n$th power residue symbol does not just have two nonzero values, "1 and $zeta$". Its nonzero values run over all $n$th roots of unity, in order to be multiplicative in $a$, so your description of $(frac{a}{p})_n$ is unusual (esp. since $p$ need not be prime in $mathbf Z[e^{2pi i/n}]$, e.g., $p = 41$ when $n = 5$. Where are you getting your description of power residue symbols from?
– KCd
Nov 21 '18 at 11:24
@KCd In theory, yes your assertion is correct, but here we only care about the solvability of $a=x^n pmod p$, and there is only two "values". Solvable $(1)$ or non-solvable $(-1)$ or a particular root of unity.
– J. Linne
Nov 24 '18 at 1:46
@KCd In theory, yes your assertion is correct, but here we only care about the solvability of $a=x^n pmod p$, and there is only two "values". Solvable $(1)$ or non-solvable $(-1)$ or a particular root of unity.
– J. Linne
Nov 24 '18 at 1:46
add a comment |
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%2f3005811%2fnth-power-residue-conjecture%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
active
oldest
votes
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.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- 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.
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%2f3005811%2fnth-power-residue-conjecture%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
2
Your $n$-th power residue symbol is not standard when $n > 2$: its value at numbers that are not $n$th powers mod $p$ should not be $-1$, but some $n$th root of unity if you want the symbol to be multiplicative in any reasonable way. Also, using ordinary prime numbers rather than prime ideals in $mathbf Z[e^{2pi i/n}]$ seems unusual, e.g., cubic reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/3}]$ and quartic (biquadratic) reciprocity is usually expressed in terms of $mathbf Z[e^{2pi i/4}] = mathbf Z[i]$. Your conjecture has a gap: what type of number is $z$?
– KCd
Nov 20 '18 at 23:51
@KCd changing -1 to a root of unity is only nessesary when dealing with cosets of the groups of $n$th power residues but I changed it anyways. As for $z$, like $x, a,$ and $n$ is an integer.
– J. Linne
Nov 21 '18 at 7:32
For $n > 2$, an $n$th power residue symbol does not just have two nonzero values, "1 and $zeta$". Its nonzero values run over all $n$th roots of unity, in order to be multiplicative in $a$, so your description of $(frac{a}{p})_n$ is unusual (esp. since $p$ need not be prime in $mathbf Z[e^{2pi i/n}]$, e.g., $p = 41$ when $n = 5$. Where are you getting your description of power residue symbols from?
– KCd
Nov 21 '18 at 11:24
@KCd In theory, yes your assertion is correct, but here we only care about the solvability of $a=x^n pmod p$, and there is only two "values". Solvable $(1)$ or non-solvable $(-1)$ or a particular root of unity.
– J. Linne
Nov 24 '18 at 1:46