Skip to main content
Search type Search syntax
Tags [tag]
Exact "words here"
Author user:1234
user:me (yours)
Score score:3 (3+)
score:0 (none)
Answers answers:3 (3+)
answers:0 (none)
isaccepted:yes
hasaccepted:no
inquestion:1234
Views views:250
Code code:"if (foo != bar)"
Sections title:apples
body:"apples oranges"
URL url:"*.example.com"
Saves in:saves
Status closed:yes
duplicate:no
migrated:no
wiki:no
Types is:question
is:answer
Exclude -[tag]
-apples
For more details on advanced search visit our help page
Results tagged with
Search options not deleted user 36687

Algebras of operators on Hilbert space, $C^*-$algebras, von Neumann algebras, non-commutative geometry

1 vote

An additive formula for the join of two projection operators

Since every $x \in \mathcal H$ can be deocmposed into a component in $\text{ran}(P \vee Q)$ and a component in $\text{ran}(P \vee Q)^\perp$, it is enough to show that the operator equality holds only …
passerby51's user avatar
  • 1,731
2 votes
1 answer
329 views

An additive formula for the join of two projection operators

Consider the projection lattice of $\mathcal B(\mathcal H)$, the algebra of bounded operators on a Hilbert space $\mathcal H$. In particular, for two (orthogonal) projections $P, Q \in \mathcal B(\mat …
passerby51's user avatar
  • 1,731
1 vote
1 answer
120 views

A relation among projections of a von Neumann algebra

This is a follow-up question on this. Let $A$ be a von Neumann algebra and $P$ be its projection lattice. For $p,s,q \in P$, let us define $ p \perp q \mid s \iff ps^\perp q = 0$ where $s^\perp = 1- …
passerby51's user avatar
  • 1,731
2 votes
1 answer
139 views

A congruence relation on the projection lattice

This question is a continuation of what I asked here. Tristan Bice showed the following nice result there: Let $A$ be a von Neumann algebra and $P$ its projection lattice, ordered by $p\leq q\Leftrig …
passerby51's user avatar
  • 1,731