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Ville Salo
Finland
http://villesalo.com
Researcher at University of Turku.
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Top Questions
27
votes
Units in the group ring over fours group after Gardam
gr.group-theory
geometric-group-theory
group-rings
group-algebras
asked Mar 6, 2021 at 10:42
mathoverflow.net
21
votes
Examples of collapsing hierarchies
big-list
hierarchy-theorems
asked Aug 4, 2020 at 13:45
cstheory.stackexchange.com
16
votes
If the center of a finite group is trivial, are there two elements whose centralizers intersect trivially?
gr.group-theory
asked Apr 24, 2018 at 9:27
mathoverflow.net
15
votes
Is homeomorphism of simplicial complexes semidecidable?
gn.general-topology
computability-theory
asked Sep 13, 2018 at 9:19
mathoverflow.net
15
votes
Does the Angel have to be really smart?
computational-complexity
combinatorial-game-theory
chess
asked Jun 2, 2020 at 1:48
mathoverflow.net
13
votes
Can matrices over $F[G]$ have infinite order when $G$ is periodic?
gr.group-theory
asked Sep 2, 2019 at 13:42
mathoverflow.net
13
votes
Splendid groups
gr.group-theory
topological-groups
asked Aug 27, 2020 at 12:26
mathoverflow.net
11
votes
Reversible polynomial circuit iff polynomial reversible circuit?
circuit-complexity
permutations
reversible-computing
asked Jan 14, 2019 at 10:39
cstheory.stackexchange.com
10
votes
Are modular lattices shallow?
lattice-theory
universal-algebra
asked Jul 4, 2023 at 6:40
mathoverflow.net
10
votes
How can you order a free group?
gr.group-theory
order-theory
free-groups
ordered-groups
asked Jan 21, 2020 at 14:10
mathoverflow.net
1
2
next
Top Answers
27
For $x$ irrational, is $a_{n} =\sum_{k=1}^{n}(-1)^{⌊kx⌋}$ unbounded?
mathoverflow.net
20
Homeomorphisms and "mod finite"
mathoverflow.net
19
An aperiodic hexagonal tile?
mathoverflow.net
18
Does Conway's game of life admit a notion of energy?
mathoverflow.net
16
Structure theorems for compact sets of rationals
mathoverflow.net
13
What is the name for a point that is periodic to within $\varepsilon$?
mathoverflow.net
10
Every mathematician has only a few tricks
mathoverflow.net
7
Is a product of Følner sets Følner?
mathoverflow.net
7
What is the Borel complexity of this set?
mathoverflow.net
7
Is there an elementary proof that distal maps are invertible?
mathoverflow.net
7
Is there an elementary proof that distal maps are invertible?
mathoverflow.net
6
Do mixing homeomorphisms on continua have positive entropy?
mathoverflow.net
6
Tiling with similar tiles
mathoverflow.net
6
Word combinatorics terminology question
mathoverflow.net
6
A Sauer-Shelah-like lermma for prefix tree
mathoverflow.net
6
Deciding homomorphic images of De Bruijn graphs
mathoverflow.net
5
Connection between entropy and the set of factors of a sequence
mathoverflow.net
5
Can matrices over $F[G]$ have infinite order when $G$ is periodic?
mathoverflow.net
5
Turing machines with all runs decidable
mathoverflow.net
5
NP-hardness of a sequence problem
mathoverflow.net
5
A property for a group generated by involutions
mathoverflow.net
5
Splendid groups
mathoverflow.net
5
Chasing game on the Go board
mathoverflow.net
5
Does $\mathbb{Z}\times\mathbb{Z}$ have an aperiodic monotile?
mathoverflow.net
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