Mixing
does the language 𝐿 = {, : 𝐿(𝑀1 ) ⊆ 𝐿(𝑀2)} is in co-RE?
$begingroup$
i was asked to determine if its in RE and if its in co-RE.
well i think its easy to say the language is not in RE but i was wondering if this language is in co-RE.
so the question is if $overline{L}$= {< 𝑀1 >, < 𝑀2 >: $ 𝐿(𝑀1 )notsubseteq 𝐿(𝑀2)$} is in RE?
my intuition is that if there is a word in 𝐿(𝑀1 ) which is not in 𝐿(𝑀2 ), we can eventually get to this word and try to run it on both machines.
turing-machines decidability
asked Jan 14 at 13:21
Ori BenamiOri Benami
63
$endgroup$
add a comment |
$begingroup$
i was asked to determine if its in RE and if its in co-RE.
well i think its easy to say the language is not in RE but i was wondering if this language is in co-RE.
so the question is if $overline{L}$= {< 𝑀1 >, < 𝑀2 >: $ 𝐿(𝑀1 )notsubseteq 𝐿(𝑀2)$} is in RE?
my intuition is that if there is a word in 𝐿(𝑀1 ) which is not in 𝐿(𝑀2 ), we can eventually get to this word and try to run it on both machines.
turing-machines decidability
asked Jan 14 at 13:21
Ori BenamiOri Benami
63
$endgroup$
$begingroup$
Since $bar L$ includes any string that is not in $L$, it includes the string $langle M1 rangle$ so your definition of $bar L$ is not correct. What you could do is prove that $L notin R$ and $L in RE$ which would mean that $bar L notin RE$ and hence $L notin$ co-RE
$endgroup$
– user137481
Jan 15 at 23:34
add a comment |
$begingroup$
i was asked to determine if its in RE and if its in co-RE.
well i think its easy to say the language is not in RE but i was wondering if this language is in co-RE.
so the question is if $overline{L}$= {< 𝑀1 >, < 𝑀2 >: $ 𝐿(𝑀1 )notsubseteq 𝐿(𝑀2)$} is in RE?
my intuition is that if there is a word in 𝐿(𝑀1 ) which is not in 𝐿(𝑀2 ), we can eventually get to this word and try to run it on both machines.
turing-machines decidability
asked Jan 14 at 13:21
Ori BenamiOri Benami
63
$endgroup$
i was asked to determine if its in RE and if its in co-RE.
well i think its easy to say the language is not in RE but i was wondering if this language is in co-RE.
so the question is if $overline{L}$= {< 𝑀1 >, < 𝑀2 >: $ 𝐿(𝑀1 )notsubseteq 𝐿(𝑀2)$} is in RE?
my intuition is that if there is a word in 𝐿(𝑀1 ) which is not in 𝐿(𝑀2 ), we can eventually get to this word and try to run it on both machines.
turing-machines decidability
turing-machines decidability
asked Jan 14 at 13:21
Ori BenamiOri Benami
63
asked Jan 14 at 13:21
Ori BenamiOri Benami
63
asked Jan 14 at 13:21
Ori BenamiOri Benami
63
asked Jan 14 at 13:21
Ori BenamiOri Benami
63
asked Jan 14 at 13:21
Ori BenamiOri Benami
63
63
$begingroup$
Since $bar L$ includes any string that is not in $L$, it includes the string $langle M1 rangle$ so your definition of $bar L$ is not correct. What you could do is prove that $L notin R$ and $L in RE$ which would mean that $bar L notin RE$ and hence $L notin$ co-RE
$endgroup$
– user137481
Jan 15 at 23:34
add a comment |
$begingroup$
Since $bar L$ includes any string that is not in $L$, it includes the string $langle M1 rangle$ so your definition of $bar L$ is not correct. What you could do is prove that $L notin R$ and $L in RE$ which would mean that $bar L notin RE$ and hence $L notin$ co-RE
$endgroup$
– user137481
Jan 15 at 23:34
$begingroup$
Since $bar L$ includes any string that is not in $L$, it includes the string $langle M1 rangle$ so your definition of $bar L$ is not correct. What you could do is prove that $L notin R$ and $L in RE$ which would mean that $bar L notin RE$ and hence $L notin$ co-RE
$endgroup$
– user137481
Jan 15 at 23:34
$begingroup$
Since $bar L$ includes any string that is not in $L$, it includes the string $langle M1 rangle$ so your definition of $bar L$ is not correct. What you could do is prove that $L notin R$ and $L in RE$ which would mean that $bar L notin RE$ and hence $L notin$ co-RE
$endgroup$
– user137481
Jan 15 at 23:34
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%2f3073222%2fdoes-the-language-1-2-1-%25e2%258a%2586-2-is-in-co-re%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%2f3073222%2fdoes-the-language-1-2-1-%25e2%258a%2586-2-is-in-co-re%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
$begingroup$
Since $bar L$ includes any string that is not in $L$, it includes the string $langle M1 rangle$ so your definition of $bar L$ is not correct. What you could do is prove that $L notin R$ and $L in RE$ which would mean that $bar L notin RE$ and hence $L notin$ co-RE
$endgroup$
– user137481
Jan 15 at 23:34