Tagged Questions
1
vote
0answers
76 views
Do particles travel backward and forward in time? [duplicate]
All these classical ideas are pointless and obsolete today, because in quantum mechanics, the particles are completely different objects, defined by quantum motion of fields, not by the location of ...
0
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0answers
34 views
Why there is no operator for time in QM? [duplicate]
Is there one central reason why there is no "Time" operator in QM?
I know this question has been asked before, but I thought I would try to stimulate some fresh thinking.
4
votes
5answers
298 views
What is $\Delta t$ in the time-energy uncertainty principle?
In non-relativistic QM, the $\Delta E$ in the time-energy uncertainty principle is the limiting standard deviation of the set of energy measurements of $n$ identically prepared systems as $n$ goes to ...
1
vote
1answer
93 views
The status / acceptance of block time?
What is the current status or acceptance of block time as it relates to Einstein's theory of relativity? Has quantum mechanics ruled it out or is it still the favored view of the world? Perhaps there ...
2
votes
0answers
57 views
How to make timelike entanglement in the laboratory?
http://io9.com/5744143/particles-can-be-quantum-entangled-through-time-as-well-as-space
http://arxiv.org/abs/1101.2565
How to make timelike entanglement in the laboratory?
How to test whether mixed ...
2
votes
1answer
305 views
Solving time dependent Schrodinger equation in matrix form
If we have a Hilbert space of $\mathbb{C}^3$ so that a wave function is a 3-component column vector
$$\psi_t=(\psi_1(t),\psi_2(t),\psi_3(t))$$
With Hamiltonian $H$ given by
$$H=\hbar\omega
...
3
votes
2answers
119 views
Why do we treat time as parameter in non relativistic QM instead of treating position as parameter?
Why do we treat time as parameter in non relativistic QM instead of treating position as parameter?
What is actually a parameter?
I have read this Wikipedia page, but could not understand why should ...
2
votes
3answers
117 views
How can an action be dependent on both its past and future?
Is it true that whenever an action takes place it is dependent on both its past and future? I mean if we already know that whatever we are doing is dependent on future as much as it is dependent on ...
1
vote
1answer
79 views
What is the difference between “at all times” and “at any particular time”?
Morrison writes in "Morrison, Michael A. : Understanding quantum physics : a user's manual"
$ |\Psi(x,t)|^2 \xrightarrow[x\rightarrow\pm \infty ]{} 0$ at all
times t [bound state]
$ ...
3
votes
2answers
287 views
Is there an observable of time?
In Quantum Mechanics, position is an observable, but time may be not. I think that time is simply a classical parameter associated with the act of measurement, but is there an observable of time? And ...
1
vote
2answers
141 views
What's the relationship between quantum entanglement and the relativity of time?
Apologies in advance for what may be a stupid question from a layman. In reading recently about quantum entanglement, I understood there to be a direct link between entangled particles, even at ...
4
votes
2answers
298 views
Does String theory say that spacetime is not fundamental but should be considered an emergent phenomenon?
Does String theory say that spacetime is not fundamental but should be considered an emergent phenomenon?
If so, can quantum mechanics describe the universe at high energies where there is no ...
5
votes
3answers
480 views
Does this Zeilinger group result provide experimental proof of backward-in-time causation?
Does this recent Zeilinger group delayed choice entanglement experiment imply backward-in-time influences?
http://arxiv.org/abs/1203.4834
From the abstract: "This can also be viewed as “quantum ...
1
vote
1answer
256 views
Is it a total or an explicite time derivative in the Schrödinger equation?
I am always dubious when I need write Schrödinger equation: do I write $\partial / \partial t$ or $d/dt$ ?
I suppose it depends on the space in which it is considered. How?
12
votes
4answers
575 views
Energy is actually the momentum in the direction of time?
By comparatively examining the operators
a student concludes that `Energy is actually the momentum in the direction of time.' Is this student right? Could he be wrong?
3
votes
3answers
553 views
Time in special relativity and quantum mechanics
The time is treated differently in special relativity and quantum mechanics. What is the exact difference and why relativistic quantum mechanics (Dirac equation etc.) works?
2
votes
2answers
361 views
Is Time Significant in the Double Slit Experiment
When doing the classic double slit experiment is the time between emitting photons significant at all? Say, a single photon is emitted, the scientist waits T seconds, then emits another photon. Are ...
