Skip to main content

All Questions

Filter by
Sorted by
Tagged with
1 vote
0 answers
125 views

Probabilistic interpretation of von Neumann's approach to quantum mechanics

One of the basic postulates in the mathematical formalism of quantum mechanics is that the probability of a measurement of an observable $A$ in the state $\psi \in \mathscr{H}$ to return a value in a ...
MathMath's user avatar
  • 1,305
1 vote
1 answer
252 views

GNS Representation — A theorem from Thirring’s book

After the GNS representation for $C^{*}$-algebras is presented in Thirring's book Quantum mathematical physics, the author states the following theorem. The Spectral Theorem: For any given Hermitian (...
MathMath's user avatar
  • 1,305
3 votes
0 answers
219 views

Can any POVM be induced by a quantum instrument?

I suspect this is the obvious result of something in operator algebras, but that's far outside my field. Recall that a projection-valued measure is a map $E$ from a sigma-algebra $\mathcal{F}$ on ...
Yonah Borns-Weil's user avatar
2 votes
1 answer
393 views

Is there a Hilbert space approach to commutative probability theory on locally compact spaces?

I was recently made aware (thanks to the answers on Why does Riesz's Representation Theorem apply in quantum mechanics?) that the $C^*$ algebra approach and the Hilbert space approach to quantum ...
Andrew NC's user avatar
  • 2,071
4 votes
0 answers
119 views

Relationship between canonical commutation relations and projective representations?

$\DeclareMathOperator\CCR{CCR}\DeclareMathOperator\Im{Im}\DeclareMathOperator\PU{PU}$Let $V$ be a real vector space equipped with an antisymmetric bilinear form $\omega$. Recall that there is a $C^\...
Tim Campion's user avatar
  • 63.9k