bio | website | |
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location | ||
age | ||
visits | member for | 5 years, 10 months |
seen | 2 days ago | |
stats | profile views | 795 |
Jun
5 |
revised |
When is $f(x^d)$ irreducible?
added 344 characters in body |
Jun
5 |
revised |
When is $f(x^d)$ irreducible?
added 75 characters in body |
Jun
5 |
answered | When is $f(x^d)$ irreducible? |
Jun
5 |
accepted | The space of polynomials with all real roots |
Jun
5 |
revised |
The space of polynomials with all real roots
added 255 characters in body |
Jun
4 |
asked | The space of polynomials with all real roots |
Apr
27 |
comment |
What is the fan of the toric blow-up of $\mathbb{P}^3$ along the union of two intersecting lines?
Well, $w \equiv 0$ on both $C_i$, so definitely $wz$ is in the ideal, no? |
Apr
23 |
comment |
induced map on tangent bundles from blow up morphism
Note that tangent bundle is dual to cotangent bundle. Since the cotangent space at a point $y \in Y$ is simply $m_y/m_y^2$, where $m_y$ is the ideal of $y$, given a morphism $\phi: Y \to Z$ such that $\phi(y) = z$, you get an induced map from the cotangent space at $z$ to the cotangent space at $y$. Now dualize. |
Feb
28 |
comment |
Blowing-up a point in the singular locus
Can you please add the definition of an ordinary singularity? |
Feb
24 |
comment |
“Exceptional components” of the exceptional divisor of a blow up
@KarlSchwede: yes, $\overline{\lbrace P \rbrace} \neq V$, and you are right in all other counts. |
Feb
24 |
asked | “Exceptional components” of the exceptional divisor of a blow up |
Jan
20 |
accepted | Is being reduced a generic property of schemes? |
Jan
19 |
comment |
Is being reduced a generic property of schemes?
Dear Sándor, not sure I get the example: your $Y$ is nowhere reduced, so it does not satisfy the assumption of being generically reduced. |
Jan
19 |
asked | Is being reduced a generic property of schemes? |
Nov
5 |
awarded | Yearling |
Aug
25 |
comment |
A question on resolution of singularities
Is it true that $\pi$ restricts to an isomorphism on $Y\setminus \pi^{-1}(\{p\} \cup L)$, so that it does not change any point on $\mathbb{P}^4 \setminus (\{p\} \cup L)$? If this is true then the answer is clearly negative. |
Jul
2 |
awarded | Curious |
Jun
29 |
revised |
What is the probability that a random sequence of polynomials is regular?
deleted 5 characters in body |
Jun
26 |
answered | What is the probability that a random sequence of polynomials is regular? |
Mar
25 |
comment |
Jacobian of an injective mapping
@user126154: you are right. I saw in the question $J_f(a) < 0$, and immediately interpreted $J_f$ as the Jacobian determinant. |