All Questions
Tagged with electromagnetic-radiation photons
622
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What is the electric field strength of a photon? In $\rm V/m$ or $\rm N/C$? Or its magnetic field in Gauss or Tesla? For visible light, or gamma rays? [closed]
I am thinking of this now because I have been learning about the Schwinger limit (or Schwinger effect)...
Supposedly, a strong-enough electric and/or magnetic field creates a 'nonlinear' effect in the ...
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Why does radiation of small wavelength interact with small objects?
I was reading chapter 2 from the book 'Diagnostic Radiology Physics : A handbook for Students and Teachers', and came across the following quote
"X rays of energy of a few tens of ...
- 273
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3
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Photonic black holes
"Can a photon turn into a black hole?" - usually the answer to this question is - it can't, because it has zero rest mass. However, when we derive the Schwarzchild Metric initially the $2M$ ...
- 1,141
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How many photons pass through us every second?
I just read this answer https://physics.stackexchange.com/a/229374, which says that, when a magnet rotates, photons are emitted with wavelength $λ=c/f$, where $f$ is the frequency of rotation. And ...
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Is luminescence from impact of fast neutral atoms/molecules on a suitable substance known?
Cathodoluminescence is emission of photons by electrons impacting on a luminescent material.
The Rutherford scattering experiments detected impacting helium nuclei on a phosphor screen.
Many other ...
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What is light? how is it connected to electromagnetic radiation?
I am trying to understand how light works and electromagnetic radiation, from what I understand charges cause disturbances in electric fields, which triggers a magnetic field, and then the back and ...
2
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1
answer
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Is energy contained in/transferred by light really discrete or is it continuous? [duplicate]
I don't really understand the wave-particle duality of light.I don't really understand the idea of photon, The idea of photon that is generally taught is that it is a fundamental unit of light with ...
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2
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Single photon detection
Consider a thought experiment where we have a source emitting a single photon, like an atom/molecule going from an excited energy state to its ground state.
We have an infinite number of point ...
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If helicity of photons is +1 then the light is right- or left-circularly polarized?
In particle physics, we say: a particle has +1 helicity (right-handed) if its momentum and spin are parallel, or it has -1 helicity (left-handed) if its momentum and spin are antiparellel.
Now, if we ...
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How does a photon look like in QFT? [closed]
It is very well known that in QFT the particles are excitations of the field. But how exactly is a free photon looking like in spacetime? What is it shape in free space? And what is in fact in the ...
- 651
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Photon propagation paradox, what am I missing? [closed]
I've seen photons and EM waves be described like so "Electromagnetic waves can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields."
So if we have a ...
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Behavior of a single emitted photon [duplicate]
Suppose you have a transmitter sending out a single photon. If you think about this photon as a wave, you will see a circular wave moving away from the transmitter. Over millennia, this wave spreads ...
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What fraction of the universe's energy is contained in photons?
From each point in the universe, the light of billions of stars, galaxies, supernovae etc. can be detected. So there seems to be a lot of energy/momentum "in flight".
Is it possible to ...
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What is the speed of light during reflection? [duplicate]
What is the speed of light in a vacuum when the light reflects off of a mirror?
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Photons and Bremsstrahlung radiation
When fast electrons goes into a target, part of their kinetic energy is converted into electromagnetic radiation, that we call Bremsstrahlung radiation, as they change their velocity. The energy ...
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