Where Do Photons Go After They Are Created?

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Discussion Overview

The discussion revolves around the fate of photons after their creation, exploring concepts related to their absorption, emission, and the implications for the number of photons in the universe. Participants examine whether photons cease to exist or if they continue to be produced indefinitely, touching on both theoretical and conceptual aspects of electromagnetic radiation.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that photons are absorbed by electrons but are then re-emitted, leading to questions about whether they are truly eliminated or simply transformed.
  • Others argue that when photons are re-emitted, they can be at different frequencies, such as UV light being absorbed and emitted as visible light, or visible light being converted to heat.
  • A participant mentions that the frequency of photons decreases over time, potentially leading to background radiation that is less noticeable.
  • There is a discussion about the limitless production of photons and the concept of energy density in the photon field, suggesting that the number of photons alone does not convey meaningful information without considering energy density.
  • Some participants clarify that photons are chargeless and that while the electromagnetic field is generated by charges, it itself does not carry a charge.
  • A participant questions whether photons can be emitted at the same frequency and whether there is a normal "life" cycle for photons, expressing uncertainty about the terminology used.

Areas of Agreement / Disagreement

Participants express differing views on the fate of photons, with some suggesting they are transformed into other forms of energy while others question the implications of continuous photon production. The discussion remains unresolved, with multiple competing perspectives presented.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about photon behavior, the definitions of terms used, and the lack of resolution on the mathematical or physical principles governing photon absorption and emission.

magicman54494
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I need to explain a bit before asking my question. I have been reading about where photons come from and I feel I understand that part fairly well. I am wondering where they end up. It only makes sense that without photons being eliminated there would eventually be more and more and more. I read that they are absorbed by electrons but from what I understand they are again released so they really arent eliminated by that means. There seem to be conflicting info as to whether they are absorbed and released or absorbed and a new photon emitted. In eithor case it's a one to one ratio so it ends up being a wash in reguards to elimination. So my question is: Where do photons go? Do they ever cease to exist or are there just more and more created?

Also I read that they are electromagnetic but I also read that they don't have an electrical charge. I don't understand. can someone explain this?
 
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Hey Magicman, I might be wrong on this, so if I am I hope that someone will correct me. Anyway though. When photons are readmitted they don't have to be readmitted at the same frequency. For example, some types of substances can absorb UV light and readmit it as visible like. When one photon of UV light is absorbed two photons (or maybe more I am not sure) of visible light are emitted. And many other kinds of substances can absorb visible light and readmit it as heat. And after that the inferred photons can be absorbed and admitted at an even lower frequency. I guess what I am trying to get at is that the frequency of the photons keeps going down, so that in the end it just becomes background radiation that we would not notice. You might already know this, but photons are bosons, so an infinite number can occupy the same space. The number of photons that can be produced is limitless. Also as the universe expands it thins these photons out.

If I am wrong on any of this, I would like to be corrected by someone.

They don't have a charge because they are the charge.
 
Forestman said:
The number of photons that can be produced is limitless.
Yes, but numbers are meaningless, just because of that. The only thing that counts is the energy density of the photon field (i.e., the electromagnetic radiation field), and a number of related field quantities.
Forestman said:
If I am wrong on any of this, I would like to be corrected by someone.

They don't have a charge because they are the charge.
Photons are chargeless. The electromagnetic field is generated by charges, but it is not charged itself.
 
Forestman said:
When photons are readmitted they don't have to be readmitted at the same frequency.
Are they sometimes emitted at the same frequency?


Forestman said:
I guess what I am trying to get at is that the frequency of the photons keeps going down, so that in the end it just becomes background radiation that we would not notice.

Is this the normal "life" of a photon? I'm not educated in physics so I might not be using the right terminology. It just seems to me that if some sort of order or balance is to be maintained that if photons are constantly being made being made some would have to go away.
 

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