Luiz Cordeiro
  • Member for 8 years, 10 months
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1 answers
17 votes
184 views
5 bookmarks
A general "inclusion-exclusion principle" / Formulas like $\inf(a,b)\sup(a,b)=ab$
1 answers
14 votes
2k views
6 bookmarks
Prove that a covering map is a homeomorphism
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13 votes
1k views
5 bookmarks
Dual and completion of metric spaces
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9 votes
2k views
2 bookmarks
Does the boundary of an open set have measure zero (in $\mathbb{R}^n$)?
2 answers
9 votes
4k views
5 bookmarks
Non-measurable set in product $\sigma$-algebra s.t. every section is measurable.
3 answers
8 votes
884 views
4 bookmarks
How to prove that $(u-v)^+\in W_0^{1,2}(\Omega)$, if $u\in W_0^{1,2}(\Omega)$, $v\geq 0$.
1 answers
7 votes
1k views
Maximal abelian subalgebra of Banach algebra is closed and contains the unit
1 answers
6 votes
286 views
2 bookmarks
Relation between tracial states on von Neumann algebras and their GNS representations
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6 votes
364 views
1 bookmarks
Continuity of double centralizers in Banach algebras
1 answers
5 votes
589 views
2 bookmarks
Positive elements of a $C^*$ (MURPHY, ex 2-2).
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4 votes
406 views
5 bookmarks
Equivalent definitions for strictly positive elements
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2 votes
486 views
2 bookmarks
Conditions for a Monoid to be a topological monoid
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2 votes
1k views
1 bookmarks
Direct (Inductive) limit of (locally convex) TVEs and universal property
1 answers
1 votes
2k views
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Elementary proof that $*$homomorphisms between C*-Algebras are norm-decreasing
1 answers
1 votes
106 views
If $u\in L^p$, is $u\in L^q$ for some $q>p$?
1 answers
1 votes
99 views
1 bookmarks
Roots in Banach algebras.
1 answers
1 votes
64 views
Are the eigenvalues limited?
1 answers
0 votes
71 views
Unicity of order/positives in ordered field
1 answers
0 votes
213 views
If $\lambda$ is isolated in $\sigma(u)$, then $E(\left\{\lambda\right\})(H)=\ker(u-\lambda)$.
1 answers
0 votes
189 views
Characterization of linear functions in $\mathbb{R}$ using distance