User Ehsaan

4

15

votes

0

answers

225

views

Is there a group $G$ for which $\mathrm{Aut}(G) \simeq (\mathbb{R},+)$?

group-theory automorphism-group

Dec 5 at 20:17 Ehsaan 2,890

3

11

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3

answers

556

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8

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1

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546

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group-theory profinite-groups pro-p-groups

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5

8

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228

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abstract-algebra commutative-algebra modules projective-module

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2

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functional-analysis hilbert-spaces

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4

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1

answer

218

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If $R$ is a simple ring, is every corner $eRe$ simple?

ring-theory noncommutative-algebra idempotents

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Is there a (f.g., free) module isomorphic to a quotient of itself?

abstract-algebra ring-theory

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abstract-algebra

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1k

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algebraic-geometry sheaf-theory vector-bundles

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measure-theory semigroups filters

Mar 6 '20 at 20:49 Ehsaan 2,890

2

votes

1

answer

56

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combinatorics semigroups ramsey-theory

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1

2

votes

1

answer

48

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81

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2

votes

0

answers

49

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If $G$ is a topological/algebraic group, is there a purely group-theoretic interpretation of $G^0$?

group-theory topological-groups

Nov 30 '16 at 22:09 Ehsaan 2,890

2

votes

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answers

58

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group-theory topological-groups pro-p-groups

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2

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256

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algebraic-geometry sheaf-theory vector-bundles

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109

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1

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622

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“Local free”ness in vector bundles and projective modules

ring-theory commutative-algebra

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75

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group-theory ring-theory representation-theory

Jul 25 '13 at 16:58 Ehsaan 2,890

1

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0

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43

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ring-theory education

Aug 6 at 12:21 rschwieb 131k

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Is there a group $G$ such that $\mathrm{Aut}(G)\simeq (\mathbb{Q},+)$? [duplicate]

group-theory

Jun 19 '19 at 19:21 Ehsaan 2,890

1

vote

1

answer

30

views

If $P/I_kP$ are finitely-generated, is it true that $P/IP$ is finitely-generated where $I=\bigcap I_k$?

ring-theory modules projective-module

Apr 8 '16 at 17:17 Ehsaan 2,890

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37 Questions

Is there a group $G$ for which $\mathrm{Aut}(G) \simeq (\mathbb{R},+)$?

Examples of subgroups where it's nontrivial to show closure under multiplication?

Nontrivial examples of pro-$p$ groups

Morita equivalent rings have homeomorphic spectra?

Algebraic results using lower K-theory as a blackbox

Inducing homomorphisms on localizations of rings/modules

Rank of projective module defined as the smallest $n$ such that $P$ is a direct summand of $R^n$

Prove that semi-simple rings are Dedekind-finite

If the torsion subset of a group has “finite index”, is the group torsion?

If $H$ is a Hilbert space, does the coordinate projection $\pi :H\oplus H\rightarrow H$ take closed subspaces to closed subspaces?

If $R$ is a simple ring, is every corner $eRe$ simple?

Is there a (f.g., free) module isomorphic to a quotient of itself?

If $N$ and $G/N$ are virtually solvable, then $G$ is virtually solvable?

Ultralimit extends limit of nets?

If $(x_n)$ is a linear recurrence, is the same true for the subsequence $(x_{pn+q})$?

Quotient of locally free sheaf is locally free?

An extension of line bundles splits locally

Is ultrafilter convolution a special case of convolution of probability measures?

When are a set and its complement both syndetic?

Characterization of real intervals $[a,b]$ as posets

Hadamard quotient of D-finite series

If $G$ is a topological/algebraic group, is there a purely group-theoretic interpretation of $G^0$?

Proof that a particular subgroup is proper

Sheaf of sections vanishing at a point is $\Gamma(E) \otimes I_p$

Prove that $H^1(\mathcal{M}^*)=0$.

“Local free”ness in vector bundles and projective modules

If $\mathbb{C}[G]$ is Noetherian and $G$ has a representation on $V$, when must $V$ be finite-dimensional?

Motivation for the definition of prime and maximal ideals [duplicate]

Is there a group $G$ such that $\mathrm{Aut}(G)\simeq (\mathbb{Q},+)$? [duplicate]

If $P/I_kP$ are finitely-generated, is it true that $P/IP$ is finitely-generated where $I=\bigcap I_k$?