User R.P.

78 votes

0 answers

3k views

The exponent of Ш of $y^2 = x^3 + px$, where $p$ is a Fermat prime

asked Dec 10, 2013 at 16:31

17 votes

2 answers

2k views

Origin of the term "Diophantine equation"

asked May 25, 2015 at 23:04

14 votes

2 answers

2k views

Surjectivity of reduction maps of elliptic curves over Q

asked Nov 20, 2012 at 18:03

12 votes

0 answers

265 views

Galois groups of classical differential equations

asked Oct 25, 2016 at 22:22

11 votes

2 answers

791 views

Geometrically unirational varieties that are not unirational

asked Jun 17, 2013 at 12:46

10 votes

1 answer

592 views

Brauer-Manin obstruction on an open subset of an elliptic curve

asked Mar 28, 2021 at 15:07

8 votes

1 answer

475 views

How do you compute the primes of bad reduction?

asked Dec 13, 2012 at 13:08

7 votes

1 answer

947 views

Do torsors give a long exact sequence of cohomology?

asked Feb 4, 2013 at 14:11

7 votes

2 answers

495 views

Are ranks of Jacobians over number fields unbounded?

asked Nov 19, 2012 at 21:10

7 votes

2 answers

500 views

Obstruction to rationality of del Pezzo surfaces of degree 4

asked May 10, 2016 at 23:32

6 votes

1 answer

518 views

Is the following consequence of the Lang conjecture known?

asked Jan 27, 2014 at 15:35

6 votes

1 answer

315 views

E an elliptic curve over Z[1/N], how many p such that E(Z/p^2) = (Z/p)^2?

asked Aug 28, 2012 at 19:26

5 votes

1 answer

988 views

Spreading out flat morphisms of schemes

asked Feb 26, 2012 at 16:48

5 votes

2 answers

1k views

Singular models of K3 surfaces

asked Mar 16, 2015 at 12:13

5 votes

1 answer

442 views

In what sense can we "describe" the rational points on a unirational surface?

asked Oct 27, 2016 at 21:57

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15 Questions

The exponent of Ш of $y^2 = x^3 + px$, where $p$ is a Fermat prime

Origin of the term "Diophantine equation"

Surjectivity of reduction maps of elliptic curves over Q

Galois groups of classical differential equations

Geometrically unirational varieties that are not unirational

Brauer-Manin obstruction on an open subset of an elliptic curve

How do you compute the primes of bad reduction?

Do torsors give a long exact sequence of cohomology?

Are ranks of Jacobians over number fields unbounded?

Obstruction to rationality of del Pezzo surfaces of degree 4

Is the following consequence of the Lang conjecture known?

E an elliptic curve over Z[1/N], how many p such that E(Z/p^2) = (Z/p)^2?

Spreading out flat morphisms of schemes

Singular models of K3 surfaces

In what sense can we "describe" the rational points on a unirational surface?