current community
chat
MathOverflow
MathOverflow Meta
your communities
Sign up
or
log in
to customize your list.
more stack exchange communities
company blog
Stack Exchange
Inbox
Reputation and Badges
sign up
log in
tour
help
Tour
Start here for a quick overview of the site
Help Center
Detailed answers to any questions you might have
Meta
Discuss the workings and policies of this site
About Us
Learn more about Stack Overflow the company
Business
Learn more about hiring developers or posting ads with us
MathOverflow
Questions
Tags
Users
Badges
Unanswered
Ask Question
Profile
Activity
Emil Jeřábek
Meta User
Network Profile
Reputation
23,003
23k
14.9k
6.9k
2013
2014
2015
2016
Top tag
lo.logic
Next privilege
25,000 Rep.
Access to site analytics
Badges
2
61
103
Newest
Nice Answer
Next badge
18/25
Electorate
Impact
~
244k
people reached
170 posts edited
131 helpful flags
5,344 votes cast
summary
answers
questions
tags
badges
favorites
bounties
reputation
all actions
321
Answers
newest
activity
votes
33
Additive Subgroups of the Reals.
Mar 29 '11 at 15:51
32
Do all the roots of the polynomial lie in the unit disk?
Jun 27 '13 at 15:55
31
Do you believe P=NP?
Apr 15 '11 at 17:47
30
A puzzle about finding three points $(x,y)$, $(x,z)$ and $(y,z)$ in a subset of a square.
Feb 25 '11 at 16:36
29
Can ZFC prove it cannot derive an inconsistency in $n$ steps?
Jan 27 '15 at 14:37
25
Countable group with uncountable number of subgroups $< 2^{\aleph_0}$
Jun 17 '15 at 15:17
20
Can we find CH in the analytical hierarchy?
Sep 18 '15 at 17:31
20
Probability, that a graph G does not contain a cycle
Mar 2 '11 at 14:30
19
Special infinitary relations and ultrafilters
Apr 7 '11 at 15:21
18
Even XOR Odd Infinities?
Jan 23 '13 at 14:17
18
The NP version of Matiyasevich's theorem
Jul 20 '11 at 13:46
18
Transcendental numbers: yet another classification
Mar 29 '11 at 15:05
17
The (un)decidability of Robinson-Arithmetic-without-Multiplication?
Jul 25 '14 at 11:36
17
What metatheory proves $\mathsf{ACA}_0$ conservative over PA?
Apr 10 '13 at 12:26
17
Are there examples of nonconstructive metaproofs?
Jun 8 '11 at 15:58
17
Countable Dense Sub-Groups of the Reals…
Jun 8 '11 at 13:47
16
Is factorial definable using a $\Delta_0$ formula?
Feb 25 '15 at 13:05
15
Is the Riemann Hypothesis equivalent to a $\Pi_1$ sentence?
Jun 23 '14 at 10:42
15
Are there “non-constructive” sets in second-order arithmetic?
May 16 '14 at 16:24
15
Morse-Kelley set theory consistency strength
Feb 1 '12 at 16:24
15
Does Fermat's last theorem hold in the ordinals?
Dec 9 '13 at 14:56
15
Sums of binomials with even coefficients
Nov 4 '11 at 16:49
15
More on Lebesgue non-measurability
Aug 3 '11 at 11:12
15
Fast evaluation of polynomials
Jul 4 '11 at 16:09
15
Starting PhD at the age of 25
Mar 29 '11 at 18:49
14
Verifying the correctness of a Sudoku solution
May 6 '13 at 19:12
14
Continued Fractions from Digit Streams
Aug 26 '15 at 11:19
14
Is it easy to produce hard-to-color graphs?
May 30 '14 at 15:48
14
Is there any large cardinal beyond Kunen inconsistency?
Jul 8 '13 at 12:30
14
When does $ZFC \vdash\ ' ZFC \vdash \varphi\ '$ imply $ZFC \vdash \varphi$?
Apr 12 '13 at 10:14
MathOverflow works best with JavaScript enabled