Tagged Questions
1
vote
1answer
87 views
QFT in Quantum Computing and Control Theory?
Is QFT being applied to quantum computing and control theory?
I took yesteryear a basic course on quantum computing and if I remember correctly we didn't touch on any QFT (though I think that if it ...
4
votes
4answers
363 views
Uncertainty Principle for Information?
I'm not familiar (yet) on how Information theory can be emerged/used in QM/QFT but I was thinking about this question:
While we have Heisenberg uncertainty principle on measuring coupled observables, ...
17
votes
7answers
622 views
Is there a symmetry associated to the conservation of information?
Conservation of information seems to be a deep physical principle.
For instance, Unitarity is a key concept in Quantum Mechanics and Quantum Field Theory.
We may wonder if there is an underlying ...
1
vote
0answers
200 views
Could someone transmit a signal with equally-tuned Casimir plates across the quantum field?
It seems, one could exploit the Casimir effect to send messages across arbitrarily-large distances with carefully-tuned Casimir plates.
Obviously, relativity would preclude FTL information transfer, ...
7
votes
3answers
37 views
Operator norm directly from phase space representation of photonic quantum operator
I'm interested in calculating the operator norm of a Hermitian operator, say $B$, acting on the Hilbert space of square integrable functions. The context is I have an optical system in all its ...
6
votes
1answer
346 views
Is microcausality *necessary* for no-signaling?
There are proofs in the literature that QFT including microcausality is sufficient for it not to be possible to send signals by making quantum mechanical measurements associated with regions of ...
18
votes
3answers
1k views
Why are von Neumann Algebras important in quantum physics?
At the moment I am studying operator algebras from a mathematical point of view. Up to now I have read and heard of many remarks and side notes that von Neumann algebras ($W^*$ algebras) are important ...
