Thomas Belulovich

Providence, RI

math.brown.edu/~thobel

Age: 27

Dec
10
awarded Enlightened
Dec
10
awarded Nice Answer
Dec
9
awarded Caucus
Nov
30
revised For $n\times n$ matrices $A,B,$ and $C,$ is it always true that $\mathrm{rank}(ABC)\leq\mathrm{rank}(AC)$?
added 80 characters in body
Nov
30
answered For $n\times n$ matrices $A,B,$ and $C,$ is it always true that $\mathrm{rank}(ABC)\leq\mathrm{rank}(AC)$?
Nov
21
comment Indiscrete space has trivial fundamental group
What have you tried? Have you considered which functions into an indiscrete space are continuous?
Nov
12
answered The jelly bean box problem
Nov
3
awarded Yearling
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Aug
5
awarded Yearling
Aug
5
awarded Yearling
Jul
3
comment Prove that this affine transformation is a translation
I expect $\phi(P)P$ is the affine hull (line through) the distinct points $\phi(P)$ and $P$. This is why $\phi$ has to have no fixed points.
Jun
26
comment Proving any N x M undirected two dimensional grid is bipartite
This works. It's more concise to say that you are coloring based on the parity of $i+j$.
Jun
26
comment Proving any N x M undirected two dimensional grid is bipartite
You didn't color all the vertices -- only ones where one coordinate is even and the other odd. However, the idea is sound -- coloring based on parity will work here.
Jun
26
comment Question from Munkres algebraic topology section 58: retractions
It would probably good for your question to say what $j_*$ is (I assume the map induced on $\pi_1$, but it would be good to specify.)
Jun
10
answered Shortest path between wikipedia articles
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