How did light speed become the governor of relativity?

Click For Summary

Discussion Overview

The discussion revolves around the historical and conceptual relationship between the speed of light and the principles of relativity, particularly how light speed became integral to the formulation of relativity theories. Participants explore various aspects of relativity, including its foundational principles, the evolution of scientific thought from Newtonian mechanics to Einstein's theories, and the implications of Maxwell's equations.

Discussion Character

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

Main Points Raised

  • One participant expresses confusion about how light speed relates to relativity and compares it to Newton's laws, suggesting a possible analogy between F=mv² and E=mc².
  • Another participant challenges the analogy, stating that F=mv² is incorrect and does not hold up dimensionally.
  • A participant explains the Principle of Relativity and its implications for the laws of physics, highlighting the difference between Galilean and Lorentz invariance.
  • It is noted that Maxwell's equations lack Galilean symmetry, which led to significant conflicts in physics at the end of the 19th century.
  • One participant discusses how Einstein's acceptance of the constancy of the speed of light and the relativity principle led to the development of special relativity.
  • Another participant mentions that the conflict between Maxwell's electrodynamics and Newtonian mechanics was experimentally confirmed, unlike current theoretical conflicts between general relativity and quantum theory.
  • There is a discussion about the relationship between general relativity and quantum theory, with differing views on whether there is a theoretical schism between them.
  • Some participants express uncertainty about the definitions and implications of quantum theory versus particle physics, noting foundational differences that complicate the formulation of Quantum Gravity.
  • One participant reflects on their background in aerospace engineering and how it has affected their understanding of these concepts, while another admits to feeling less knowledgeable about the topic.

Areas of Agreement / Disagreement

Participants exhibit a range of views on the relationship between light speed and relativity, with some agreeing on the historical significance of Maxwell's equations while others debate the implications of various invariance principles. The discussion remains unresolved regarding the foundational differences between general relativity and quantum theory.

Contextual Notes

Participants express varying levels of understanding and familiarity with the mathematics and concepts involved, indicating that some assumptions may not be universally shared. The discussion touches on complex topics that may require further clarification or exploration.

Who May Find This Useful

This discussion may be of interest to individuals studying the history and principles of physics, particularly those curious about the development of relativity and the role of light speed in theoretical frameworks.

  • #31
ghwellsjr said:
Integral said:
ghwellsjr said:
How do Maxwell's equations shout out that the one-way speed of light is the same to all observers?
Yes, if you know how to listen. All you have to do is cast them in the form of the wave equation.
It is my understanding that Maxwell used his equations to derive a solution with a wave speed equal to the speed of light which led him to suggest that the propagation of light relative to the absolute rest state of the ether could be determined by a suitable experiment with enough precision, so he obviously missed the shouting coming from his own equations that the speed of light is the same to all observers.
Maxwell was listening to too much shouting coming from elsewhere, "All wave phenomena require a medium. Everyone knows that!" and "The universe obeys Galilean invariance. Everyone knows that!", to hear the shouting from his own equations. One last bit of shouting is that physicists at Maxwell's time much preferred dynamics over kinematics. Special relativity is very much a kinematics theory.

For Maxwell to have derived special relativity he would have had to ignore all that shouting from elsewhere. Physicists in the latter part of the 19th century thought they were on the verge of a complete dynamical description of the universe. Ignoring the "Everyone knows that" type of shouting and back-stepping to a mere kinematics description was too much for the physicists of Maxwell's time, including Maxwell himself.

But in hindsight, it is still conceivable that Maxwell could have done this. He could have, for example, looked at just how ludicrous his concept of a luminiferous aether truly was (a non-solid that somehow supports transverse waves and somehow doesn't interact with ordinary matter) and saw how it was contradicted by the known phenomena of the aberration of light.
 
Physics news on Phys.org
  • #32
D H said:
But in hindsight, it is still conceivable that Maxwell could have done this. He could have, for example, looked at just how ludicrous his concept of a luminiferous aether truly was (a non-solid that somehow supports transverse waves and somehow doesn't interact with ordinary matter) and saw how it was contradicted by the known phenomena of the aberration of light.
Yes, it is conceivable that Maxwell could have derived special relativity, if he hadn't died at such a young age, but he needed more than his equations. He needed Einstein's second postulate, which is not derivable from his equations, they were already covered in Einstein's first postulate and fully compatible with Lorentz's Ether Theory. That's my only point.
 

Similar threads

  • · Replies 19 ·
Replies
19
Views
2K
  • · Replies 76 ·
3
Replies
76
Views
6K
  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 130 ·
5
Replies
130
Views
16K
  • · Replies 45 ·
2
Replies
45
Views
7K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 15 ·
Replies
15
Views
3K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 18 ·
Replies
18
Views
2K
  • · Replies 13 ·
Replies
13
Views
3K