The Limitations of Applying Relativity to Photons

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Discussion Overview

The discussion centers on the limitations of applying the theory of relativity to photons, particularly regarding their behavior and properties in relation to time and reference frames. Participants explore conceptual and theoretical implications of photons not experiencing time and the challenges this presents within the frameworks of relativity and quantum mechanics.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants question how a photon can oscillate or "wiggle" if it does not experience time, suggesting that this raises fundamental issues about its nature.
  • Others propose that a photon oscillates due to its energy, but this explanation is challenged as being superficial and not addressing deeper inconsistencies with relativity and quantum mechanics.
  • One participant asserts that a light wave does not wiggle in time, maintaining a constant shape while propagating at the speed of light.
  • There is a discussion about whether, relative to its own frame of reference, a photon has an infinite wavelength and zero frequency, with some participants agreeing on this point.
  • Concerns are raised about the implications of a photon interacting with an absorber system, suggesting that it would perceive the absorber as having infinite mass, complicating the absorption process.
  • Participants note that a photon lacks a valid reference frame, leading to infinities when applying Lorentz transformations, and discuss the implications of this for understanding the nature of photons and relativity.
  • Questions are posed about the possibility of developing a theory that avoids these infinities and maintains mathematical consistency.

Areas of Agreement / Disagreement

Participants express multiple competing views on the nature of photons and their relationship with relativity. There is no consensus on the explanations provided, and the discussion remains unresolved regarding the implications of these ideas.

Contextual Notes

Participants highlight limitations in current understandings, including unresolved mathematical steps and the dependence on definitions of time and reference frames. The discussion reflects a range of interpretations and assumptions that are not fully reconciled.

NewLocality
[SOLVED] Is relativity Uncertain

Simple question: -
If a photon does not experience time how does it know how many times to
wiggle as it crosses space.
 
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It oscillates (wiggles) because of its energy, its frequency can decrease or increase to keep propagating at c through any field. But a photon doesn't know to die or better yet decay. A photon emmited during the big bang is still here today at 0 years old. It is emmited at a certain frequency and wavelength and travels its path. A photon doesn't experience time because it travels at c. Anything traveling at c will have a zero variation world line. But of course nothing with mass can travel at c as Einstein prooved.
 
Hi DB

Your answer really does not address the problem. To say the photon oscillates at a given rate because of its energy is merely referring to Planck’s equation. Planck himself never attempted to explain the mechanism behind the formula.

It is true at a superficial level the photo-electric effect and the Compton effect seem to substantiate the idea of the photon but at a deeper level we find that it is inconsistent with the theory of relativity and also some aspects of quantum mechanics. Special relativity denies it the time for it to come into being and quantum mechanics demands that it be in all places at the same time. I admire your confidence in attempting to answer my question but I think a little more is required.
 
Last edited by a moderator:
NewLocality said:
Simple question: -
If a photon does not experience time how does it know how many times to
wiggle as it crosses space.

A light wave doesn't wiggle in time. It's shape stays constant (in vacuum)
and just shifts along with the speed of c. At the most it can spread because
not all parts move exactly in the same direction. The EM components at the
head or the tail of the light pulse stay always directed in the same direction.

Regards, Hans
 
Hi Hans

Does this mean relative to its own frame of reference the light has an infinite wave length?

Regards, NL
 
Last edited by a moderator:
NewLocality said:
Hi Hans

Does this mean relative to its own frame of reference the light has an infinite wave length?

Regards, NL

Yes, it's frequency is zero in it's own reference frame. It's maximally Red shifted:

[tex]f' \ \ = \ \ \sqrt{\frac{c-v}{c+v}} \ f[/tex]

Regards, Hans
 
Hans de Vries said:
Yes, it's frequency is zero in it's own reference frame. It's maximally Red shifted:

[tex]f' \ \ = \ \ \sqrt{\frac{c-v}{c+v}} \ f[/tex]

Regards, Hans

A few tips to understand what's going on:


You can draw a Minkovsky diagram. The light phases are bands at 45
degrees in parallel with the x' and t' axis.

You'll see that the frequency over the t' axis is zero.

And this one: The 'head' of a photon can never see it's own tail since
this would need propagation > c. The "head" can only see it's own phase,
(=> 0 Hz) The other parts of the photon are all mapped on it's light cone.

(What we call photon is spatially extended on the x-axis)


Regards, Hans
 
In that case when a photon interacts with an absorber system, the photon will see the absorber system as having infinite mass and a Debroglie frequency that is also infinite. The photon could never be fully absorbed because the universe would have grown old and died long before the process could be completed.
 
A photon doesn't have a valid reference frame, because you get infinities if you try to apply the Lorentz transformations using v=c. You can consider the limit as v approaches c, but this gives you weird answers, like that a photon would experience its entire path throughout history as a single point in space which takes zero time to traverse.
 
  • #10
JesseM said:
A photon doesn't have a valid reference frame, because you get infinities if you try to apply the Lorentz transformations using v=c. You can consider the limit as v approaches c, but this gives you weird answers, like that a photon would experience its entire path throughout history as a single point in space which takes zero time to traverse.

So what's that telling us about the nature of the photon and its relationship with relativity?

Why is not possible to have theory which is free from these infinitives and we can apply mathematics to it in a self consistent way?
 

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