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"I would never die for my beliefs because I might be wrong."

-- Bertrand Russell


Apr
28
comment Can photons travel faster than $c$? (Feynman Lectures)
I'd say no. But someone else might disagree. What is certain is that it's the computational procedure that requires adding arrows for all processes. Even if they involve apriori unphysical things.
Apr
28
comment Can photons travel faster than $c$? (Feynman Lectures)
The arrows are representing the wave function, or rather infinitesimal pieces of the wave function of the photons. What Feynman is describing in layman's terms is the path integral in quantum mechanics.
Mar
1
comment Can I state that $\Psi (x_1, \dots , x_n,t)= \sum_{i=1}^n a_i \psi (x_i,t) $ via superposition?
To put ir succinctly: no you can't do that.
Jan
28
comment What exactly is 'Dark Matter'?
possible duplicate of How do we know Dark Matter isn't simply Neutrinos?
Dec
8
comment Understanding of the $m v^2/2$ formula for kinetic energy
Yes, the weight is definitely non negligible. The relationship between terminal velocity and amount of fuel will not be linear like you assume.
Nov
25
comment How to use specific heats and temperature change in a system to calculate mass?
That's because this stackexchange has made the decision to not allow homework questions.
Nov
22
comment Can Quantum Entanglement and Quantum Superposition be considered the same phenomenon?
All entangled states are special cases of superposed states. But not all superpositions are entangled states.
Nov
18
comment What is wrong with the De Broglie–Bohm theory a.k.a “Causal Interpretation” of quantum theory?
@bright magus: If you say so. See you, I'm off throwing away all my books about classical phase space.
Jun
17
comment Can we use quantum entanglement as a way to send information or data?
Entanglement is used as a means to create secure communication, but the essential information is still sent through a classical channel.
May
27
comment Is there physics behind the layout of a piano keyboard?
Or better even, isomorphic keyboards.
May
27
comment Is there physics behind the layout of a piano keyboard?
The thing is, there's definitely physics involved in the workingsof a piano. But the specific layout of the keyboard is really just a convenient choice. If you search a bit for it, you'll find many other keyboard layouts that were used in history. Take for instance enharmonic keyboards. Those are way better than our more common keyboards in that you can play just intervals with them. If pure physics was the motivation to select a keyboard, we should all opt for an enharmonic one.
May
18
comment Speed of light as a universal speed limit
@Mew: But you can postulate the existence of particles (tachyons) that are already faster than the speed of light and hence don't need to be accelerated. This is consistent with the Lorentz-transformations. However, it does indeed lead to the problem with the future being able to influence the past. It also has another problem of instability, in that it is possible to keep extracting energy out of those tachyonic particles.
Apr
21
comment Quantum entaglement and the arrow of time
If the article means that they have a quantum mechanical explanation for the special initial conditions that lead to the arrow of time, why not. But anything else is misguided. I also note the "complex and disgusting mess that explains nothing" in your quote. Doesn't really invite to read further.
Apr
15
comment The speed of light and unstable matter
No, with the critical mass, you are thinking about something like an atomic bomb. Now, the thing is that while the mass would increase, you'd still have as many atoms in the material. And therefore not enough to get a chain reaction and thus an explosion.
Apr
13
comment What is the principle of equivalence in thermodynamics?
Yes, that's it.
Mar
30
comment First-order wave equation: Why is its presence not common?
It's still first order.
Mar
30
comment First-order wave equation: Why is its presence not common?
The Dirac equation is a first order wave equation.
Mar
16
comment Quantum Wave Mechanics
If something satisfying a wave equation is not a wave, then what is? This is not a physics question but a semantics discussion.
Mar
14
comment Superconducting loop as a particle detector?
en.wikipedia.org/wiki/Cryogenic_particle_detectors
Mar
5
comment Does limit $\hbar \rightarrow 0$ in Quantum Mechanics mean anything?
@Lubos: yes of course, lapsus.