12,886 reputation
11944
bio website math.brown.edu/~ysolomon
location Providence, RI
age
visits member for 3 years, 8 months
seen 4 hours ago

First-year graduate student at Brown.


Apr
13
answered If a nonempty set of real numbers is open and closed, is it $\mathbb{R}$? Why/Why not?
Apr
2
answered Can a transcendental number be an infimum of a set of rationals?
Mar
30
revised Is there a Taylor series for vector cross product?
edited tags
Mar
29
comment Gradient Ricci soliton
Doesn't being locally zero imply being globally zero for analytic objects?
Mar
28
revised Why are mathematicians more interested in elliptic curves than other algebraic curves?
added 27 characters in body
Mar
27
revised Is the Dirac Delta “Function” really a function?
deleted 1 characters in body
Mar
26
revised Am I wrong in thinking that $e^{i \pi} = -1$ is hardly remarkable?
added 73 characters in body
Mar
26
answered Am I wrong in thinking that $e^{i \pi} = -1$ is hardly remarkable?
Mar
24
comment Find a value $c$ such that $\left\|\begin{pmatrix} x^2 - y^2\\2xy \end{pmatrix}\right\| \leq |c|\left\|\begin{pmatrix} x\\y \end{pmatrix}\right\|$
That was added later and makes the problem trivial.
Mar
24
comment Find a value $c$ such that $\left\|\begin{pmatrix} x^2 - y^2\\2xy \end{pmatrix}\right\| \leq |c|\left\|\begin{pmatrix} x\\y \end{pmatrix}\right\|$
$\sqrt{z}$ is not constant.
Mar
24
answered Find a value $c$ such that $\left\|\begin{pmatrix} x^2 - y^2\\2xy \end{pmatrix}\right\| \leq |c|\left\|\begin{pmatrix} x\\y \end{pmatrix}\right\|$
Mar
24
revised How do we explain the existence of complex conjugation?
added 317 characters in body
Mar
24
revised How do we explain the existence of complex conjugation?
added 317 characters in body
Mar
24
answered How do we explain the existence of complex conjugation?
Mar
23
reviewed Approve suggested edit on Solve differential for general solution
Mar
21
comment Is this a vector space?
Is the zero matrix in there?
Mar
20
awarded  Good Answer
Mar
17
answered Let $R$ be a Noetherian ring. Then all finitely generated $R$-modules are Noetherian
Mar
13
comment Matrix multiplication as combination of rotation and stretching
I might be mistaken here (I'm not too knowledgeable about this area), but I think that is correct. SVD is a powerful tool and proving that it exists is tantamount to showing that one's matrix can be decomposed into rotations, scalings, and rotations (in that order).
Mar
13
answered Matrix multiplication as combination of rotation and stretching