All Questions
Tagged with electromagnetic-radiation photons
622
questions
2
votes
0
answers
32
views
Link between photon helicity and polarization of $A^\mu$ electromagnetic potential
From Wigner theorem we know that the irreducible unitary representation of the Poincarè group for massless and spin 1 particle is labelled by the momentum $p_\mu$ and the two possible helicity $+1,-1$ ...
- 207k
3
votes
3
answers
182
views
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 $2M$ ...
- 9,500
0
votes
1
answer
49
views
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 ...
- 73.7k
84
votes
3
answers
10k
views
Can photons be detected without being absorbed?
I am thinking about a detector that would beep if light passes through it. Is it possible?
- 46.1k
0
votes
1
answer
100
views
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 ...
- 59.6k
0
votes
2
answers
223
views
Can polarization states of a photon be understood in terms of spatial orthogonality/dimensions?
For example, do the terms 'horizontal', 'vertical', 'diagonal' and 'anti-diagonal' polarization have any relevance to the physical, quantum state of a photon, or are they simply descriptive of how one ...
CommunityBot
- 1
1
vote
2
answers
44
views
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 ...
- 27.1k
2
votes
2
answers
112
views
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 ...
- 46.1k
9
votes
2
answers
3k
views
Why doesn't photon lose energy over distance?
In an atom, ( or even an oscillating circuit) When an electron falls from higher energy level to a lower one, it gives a photon of energy $hf$. On other hand it can be considered as an accelerated-...
0
votes
4
answers
274
views
How does blackbody radiation suggest the quantization of energy?
I have read about Wein's law and Rayleigh-Jeans law which were apparently based on classical mechanics and couldn't explain the radiation spectrum of a blackbody.
Then Planck came up with the ...
- 12.1k
1
vote
1
answer
87
views
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 ...
- 207k
2
votes
1
answer
54
views
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 ...
- 207k
6
votes
3
answers
12k
views
Is the energy of a photon continuous/discrete?
I was struggling today with this question: does a free photon have a continuous energy spectra?
Free means in no context of any energy system (eg. an atom, em field). Although I'm asking myself if ...
- 207k
2
votes
5
answers
475
views
Is a photon a single wavelength of monochromatic light?
I am confused about all these different interpretations of what a photon is?
I am looking for a simple and practical interpretation.
Therefore, I am asking herein if a single photon corresponds to a ...
2
votes
1
answer
79
views
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 ...
rob♦
- 91.5k