Length Contraction oes the object or travel distance shrink?

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Discussion Overview

The discussion centers around the concept of length contraction in the context of special relativity, specifically questioning whether it is the object that shrinks or the distance traveled that is affected. Participants explore different perspectives on the implications of length contraction, particularly in relation to photons and frames of reference.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Exploratory

Main Points Raised

  • One participant questions whether length contraction implies that the object itself shrinks or if it is the travel distance that is affected.
  • Another participant asserts that if the article's claim about photons not traveling any distance is accurate, it is nonsensical.
  • A participant provides a link to an article discussing the experience of photons and time, suggesting that the framing of the question is problematic.
  • Some participants argue that no material object can be measured to travel at the speed of light, challenging the validity of using photons as examples in this context.
  • One participant explains that length contraction depends on the observer's frame of reference, noting that different observers perceive contraction differently based on their relative motion.
  • Another participant expresses confusion about the implications of universal contraction, suggesting that spacetime is the fundamental construct influencing perceptions of time and space.
  • One participant comments on the surprising nature of physics in general, indicating a broader sense of uncertainty in the field.

Areas of Agreement / Disagreement

Participants express disagreement regarding the interpretation of length contraction, particularly in relation to photons and the nature of spacetime. There is no consensus on the implications of the discussed article or the validity of its claims.

Contextual Notes

Some statements made by participants rely on specific interpretations of relativistic concepts and the nature of frames of reference, which may not be universally accepted or understood. The discussion includes assumptions about the behavior of objects at relativistic speeds and the definitions of contraction.

Superposed_Cat
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Length Contraction:Does the object or travel distance shrink?

I had always thought that length contraction meant that the object itself shrunk but I stumbled across an article where they said "Because of length contraction the photon doesn't travel any distance at all. Which is it? Any help appreciated.
 
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You should always link an article if you're going to draw phrases from it. If that is what the article said verbatim then it is a nonsensical statement.
 
Some of the answers are wrong too

... but if he were a real man with real mass, he would have become a black hole singularity and would never ever again notice any time at all …
This is nonsense. No material object can be measured to be traveling at the speed of light.
 
The article is completely nonsensical.
 
In answer to the question in the thread title: it depends on the frame of reference. Whatever is doing the moving is length contracted. If you're sitting on a train, from your point view as the world whizzes past you, it is contracted. The distance you perceive between two points that pass by you in succession is less than the rest frame distance of those two points. On the other hand, from the point of view of a person standing next to the track, it's the train that is contracted.

I agree that using a photon as the example moving object was a bad idea, since a photon rest frame cannot be defined. EDIT: I also agree that this article is bunk. What supposed "physicist" is doing the answering here?
 
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I have no idea. I just followed a link after reading another article. So the entire universe is contracted?
 
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Superposed_Cat said:
I have no idea. I just followed a link after reading another article. So the entire universe is contracted?

Sure. This seems surprising until you realize that what's going on is that spacetime is the fundamental construct. The direction through spacetime that is experienced as "time" and the directions that are experienced as "space" are different for different observers in relative motion.
 
Nah physics in general seems surprising.
 

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