8,394 reputation
11640
bio website cube.fredrikmeyer.net
location Oslo, Norway
age 25
visits member for 3 years, 7 months
seen yesterday

I'm a PhD Student at the University of Oslo, studying algebraic geometry. Emphasis on combinatorial aspects, like Stanley-Reisner rings and deformations.


1d
comment Why do only fixed points contribute to the Euler characteristic?
An algebraic scheme is usally defined as a scheme of finite type.
Jul
10
awarded  Good Question
Jul
2
awarded  Curious
Jun
28
comment on the coordinate ring of $\mathbb{A}^n \times \mathbb{P}^{m}$
@MarianoSuárez-Alvarez Ops, I meant subvarieties, not functions.
Jun
28
revised on the coordinate ring of $\mathbb{A}^n \times \mathbb{P}^{m}$
added 165 characters in body
Jun
27
answered on the coordinate ring of $\mathbb{A}^n \times \mathbb{P}^{m}$
Jun
25
answered How to show if n is prime, then $\{1,2,…,n-1\}$ is a group?
Jun
24
revised What is $T^*(\mathbb{A}^1)$?
edited tags
Jun
24
answered Question about toric ideal
Jun
23
comment Continuous, differentiablee and continuous isomorphism, homomorphism
@iffl Does the added part clarify?
Jun
23
revised Continuous, differentiablee and continuous isomorphism, homomorphism
added 429 characters in body
Jun
23
answered Continuous, differentiablee and continuous isomorphism, homomorphism
Jun
21
comment Is every prime the average of two other primes?
What is the point of the unreadable symbolic fetishism in the question? It would be better, and much easier to just write "is every prime the average of two distinct primes?".
Jun
21
comment Does the series $\sum_{n=1}^\infty\frac{\sin n}{\ln n+\cos n}$ converge?
@StevenStadnicki I agree with both of you. However, as stated, my answer is not an answer, and I believe the picture gives good insight into why this is a difficult sum to evaluate.
Jun
20
answered Does the series $\sum_{n=1}^\infty\frac{\sin n}{\ln n+\cos n}$ converge?
Jun
19
revised Prove that $\sigma_k$ is a multiplicative function
removed unnecessary tex in title
Jun
19
comment Matrix multiplication of $A \in M_{3 \times 2}$ and $B \in M_{2 \times 3}$.
To me it seems like something is wrong with your computations. $BA$ is a $2 \times 2$-matrix with determinant zero, so the maximal possible rank is $1$, whereas you have computed $2$.
Jun
9
comment Ideal equals the whole ring
@user26857 Good point, I didn't notice. I've hidden part of the answer.
Jun
9
answered Ideal equals the whole ring
Jun
9
comment $Z\subseteq\mathbb{A}^n(k)$ such that $\Gamma(Z)$ is no UFD
@principal-ideal-domain One way is to observe that both $I$ and $\ker \phi$ are prime ideals of Krull dimension one. This implies that they must be equal.