"Length contraction" prior to observation/measurement

Click For Summary
SUMMARY

The discussion centers on the implications of special relativity (SR) regarding length contraction and the nature of objective reality. It asserts that while length is frame-dependent, this does not negate the existence of an objective universe. An example illustrates that an observer moving at 0.86c measures Earth's diameter as 4000 miles, contrasting with its actual diameter of 8000 miles. The conversation emphasizes the importance of understanding concepts like Bell's spaceship paradox to grasp the nuances of SR, ultimately refuting the claim that relativity denies an objective world.

PREREQUISITES
  • Understanding of special relativity principles
  • Familiarity with length contraction and frame of reference
  • Knowledge of Bell's spaceship paradox
  • Basic grasp of relativistic physics
NEXT STEPS
  • Study the implications of length contraction in special relativity
  • Research Bell's spaceship paradox and its significance in relativity
  • Explore the concept of frame of reference in physics
  • Investigate how relativistic effects challenge classical notions of objective reality
USEFUL FOR

Physicists, students of relativity, and anyone interested in the philosophical implications of modern physics.

Michael Mooney
Messages
4
Reaction score
0
Since special relativity insists that length is not invariant but rather depends on the frame of reference from which an object or distance is observed... and since the cosmos is many billions of years older than any possible observer, then objects and the distances between them must exist independently from all varieties of referential frames.
Example: A frame of reference approaching Earth at .86c will, according to SR, measure its diameter to be about 4000 miles in the direction of the approach. But Earth hasn't changed much from its 8000 mile diameter in billions of years, so how it might appear from such a frame has nothing to do with its actual, physical diameter, which does "vary" with how it is measured.
It all comes down to the fact that SR denies an objective world in favor of an infinite number of possible "subjective" perceptions of the world. Open for discussion.
 
Physics news on Phys.org
Before you write off length contraction as something subjective, you should study and understand Bell's spaceship "paradox" - google will find many references.

In any case, it simply untrue (and probably based on a misunderstanding) to say that relativity "denies an objective world". It describes the real and objective universe in which we live - it just so happens that that universe doesn't behave the way our common sense, which is biased by a lifetime surrounded by objects moving at speeds that are small compared with the speed of light, leads us to expect.

As this thread is based on a faulty premise, it is closed
 
  • Like
Likes   Reactions: Dale

Similar threads

  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 63 ·
3
Replies
63
Views
6K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 45 ·
2
Replies
45
Views
6K
  • · Replies 11 ·
Replies
11
Views
2K
  • · Replies 17 ·
Replies
17
Views
2K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 24 ·
Replies
24
Views
3K
  • · Replies 29 ·
Replies
29
Views
3K