The discussion revolves around the nature of photons and whether all visible light sources, such as the sun and electric sparks, can be accurately described as emitting photons. Participants explore the implications of this classification, particularly in relation to the claims made by an electrical engineer regarding "true" photons and their association with specific light-emitting processes.
Participants express disagreement regarding the definition and classification of photons. While some support the view that all visible light consists of photons, others align with the electrical engineer's more restrictive definition. The discussion remains unresolved, with multiple competing views present.
There are limitations in the discussion regarding the assumptions made about the nature of light and photons, as well as the specific contexts in which different definitions may apply. The conversation reflects a blend of technical and philosophical perspectives without reaching a consensus.
K^2 said:A "ball" implies radius. A photon is a point-particle. All gauge bosons are.
Are you joking? Please tell me you are joking.Phrak said:This sounds like elephants all the way down. Suppose you have a little ball, with light in it, and you shrink it to a point. There's no where left for the electricity to fit!
K^2 said:Are you joking? Please tell me you are joking.
arunma said:Yup, that's exactly correct (except I think you mean "ultraviolet catastrophe," but whatever). Long story short: you can treat a blackbody as a box with a bunch of waves in it. If you assume that there is a continuous distribution of possible waves in the box and integrate, you reproduce the correct energy density at low frequencies, but it goes to infinity at high energies. But if you assume the waves are discrete and do a summation instead of an integral, the spectrum goes to zero at high frequency. That's the motivation for assuming that light is quantized. However, it turns out to have other applications. For example, the photoelectric effect is explained by light quantization.
Many popular histories of physics, as well as a number of physics textbooks, present an incorrect version of the history of the ultraviolet catastrophe. In this version, the "catastrophe" was first noticed by Planck, who developed his formula in response. In fact Planck never concerned himself with this aspect of the problem, because he did not believe that the equipartition theorem was fundamental – his motivation for introducing "quanta" was entirely different. That Planck's proposal happened to provide a solution for it was realized much later, as stated above.
Though this has been known by historians for many decades, the historically incorrect version persists, in part because Planck's actual motivations for the proposal of the quantum are complicated and difficult to summarize to a modern audience.
sophiecentaur said:But what if there's NO mass?
But if you pull both my legs, I'll fall!DaveC426913 said:Phrak: pull his other leg; it's got bells on it!
Even if you could establish the Schwarzschild Radius that way, which you can't because photon is delocalized, it wouldn't tell you the size of the photon.The following is one method we might examine to establish a lower bound, to first order, for the size of an isolated photon.
K^2 said:But if you pull both my legs, I'll fall!
Even if you could establish the Schwarzschild Radius that way, which you can't because photon is delocalized, it wouldn't tell you the size of the photon.
A black hole is a singularity. A point object. Despite its event horizon having a cross-section.
zoobyshoe said:The wiki article is interesting: it asserts that Planck wasn't actually trying to resolve the ultraviolet catastrophe when he introduced the notion light was quantized. He had other reasoning for it.
alxm said:Well since we're setting the record straight, he never introduced the notion that light was quantized either, but rather the "oscillators" (an abstraction he used) in material which emit light. It was Einstein with his work on the photoelectric effect who showed you could re-interpret it this way and explain both phenomena.
DaleSpam said:There are some quantum states (e.g. coherent states) where the number of photons is uncertain. But even so I am with you on this. If you don't like the idea of virtual photons then you may not want to consider a near-field antenna like a microwave to be photons, but it is certainly accepted by the QED community.
You know, this sort of humor works a lot better when every other post by other people doesn't contain similar nonsense they genuinely believe.Phrak said:No, no, no. If it fell into its own black hole it could disappear and reemerge as a glueball. The radius is the photon radius; not the Schwarzschild radius. If it didn't stay in its own photon sphere it would leak away.
K^2 said:You know, this sort of humor works a lot better when every other post by other people doesn't contain similar nonsense they genuinely believe.