2,120 reputation
21446
bio website anhhuy.ch
location Switzerland
age 22
visits member for 4 years, 1 month
seen 3 hours ago

My name is Anh Huy Truong and I am currently studying mathematics at the ETH Zürich.


Feb
15
asked How can I find a non-negative interpolation function?
Jan
14
asked How should I think about reflexive spaces? What “property” do I get from a space being reflexive?
Jan
8
accepted Why does $e_i \in \ell^2$ weakly converge to $0$?
Jan
7
asked Why does $e_i \in \ell^2$ weakly converge to $0$?
Jan
2
awarded  Favorite Question
Dec
13
accepted Showing that a matrix is positive (semi-)definite
Dec
9
comment Showing that a matrix is positive (semi-)definite
I'm sorry I didn't refer to the paper earlier. I asked for an alternative proof because the proof provided was not very intuitive to me, i.e. I would have never been able to come up with it. Since you came up independently with basically the same proof: Is there any logical reason for introducing that matrix and decomposing the matrix $D$ as in your answer? Is it just experience or is there a deeper reason? I have never seen this kind of decomposition yet which is why it was rather odd for me.
Dec
9
comment Showing that a matrix is positive (semi-)definite
@DavidSpeyer: I put it for completeness. Sorry if it confused anyone.
Dec
9
revised Showing that a matrix is positive (semi-)definite
added 104 characters in body
Dec
9
awarded  Nice Question
Dec
9
comment Is the matrix corresponding to an equivalence relation positive semidefinite?
My question actually arose from this. I had a graph and the matrix $A$ had entries $1$ if two vertices belonged to the same connected component and $0$ otherwise. However, I did not know about the eigenvalues of a clique (or maybe I just forgot).
Dec
9
accepted Is the matrix corresponding to an equivalence relation positive semidefinite?
Dec
9
comment Is the matrix corresponding to an equivalence relation positive semidefinite?
Sorry, I misread. That makes a lot more sense now.
Dec
9
asked Is the matrix corresponding to an equivalence relation positive semidefinite?
Dec
8
awarded  Talkative
Dec
7
comment Showing that a matrix is positive (semi-)definite
@Casteels: Was there a comment that is deleted now?
Dec
5
revised Showing that a matrix is positive (semi-)definite
added 39 characters in body
Dec
5
comment Showing that a matrix is positive (semi-)definite
@Casteels: I'm sorry I completely forgot. The diagonal entries are 1.
Dec
4
asked Showing that a matrix is positive (semi-)definite
Nov
30
awarded  Benefactor