How Light Travels Across Space at Velocity C

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Discussion Overview

The discussion centers on the nature of light's travel across space at the speed of light (c), exploring concepts of time, aging, and reference frames in relation to photons and other particles. It includes theoretical considerations and speculative viewpoints regarding the implications of traveling at or near light speed.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant describes a scenario where a vessel traveling close to the speed of light experiences time differently than a photon, suggesting that time does not exist for a photon, leading to the conclusion that it does not age.
  • Another participant agrees that time does not exist for an electron, implying a similar perspective on aging.
  • A participant challenges the concept of a "photon's frame of reference," stating that it does not exist.
  • There is a suggestion that space could become a two-dimensional surface rather than a point, questioning the nature of length contraction in relation to movement.
  • One participant expresses a personal opinion that the ideas of length and time contraction break down for photons, although they acknowledge a lack of scientific justification for this view.
  • A later reply clarifies that while the photon's frame of reference is non-inertial and poorly defined, the spacetime interval along its worldline is zero, complicating the definitions of proper time and distance.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the nature of time and space for photons, with no consensus reached on the validity of a photon's frame of reference or the implications of traveling at light speed.

Contextual Notes

There are limitations in the discussion regarding the definitions of time and space, particularly in relation to the behavior of photons and the implications of relativistic effects, which remain unresolved.

DB Katzin
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In another post there is an example of a vessel moving close enough to the speed of light that the journey to the galaxy Andromeda 2.5M light years takes only 4 hrs on the vessel's clock. In its own frame of reference the vessel is moving just above 600K LY/hr. Yet a photon that left at the same instant would arrive before the vessel and always be measured as traveling at velocity c with respect to the vessel. As the velocity of the vessel S/T approaches the speed of light T (actually delta t) approaches 0, ie the 2.5 M LY trip takes, 3 hrs, 1 hr, 1 minute, 1 second, etc as v approaches c. At c, T (delta t) = 0, for all distances S, implying that time does not exist for a photon. In the photon's frame of reference its arrival and departure and the trip in between are simultaneous, its velocity is effectively infinite and since no time passes it doesn't age no matter how "old" it is--how long ago it was emitted.
 
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Yes, time does not exist for an electron, it does not "age".
 
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"In the photon's frame of reference"
This does not exist.
 
Space also becomes a point.
 
Coto said:
Space also becomes a point.

Why doesn't space become a two dimensional surface, given that length is only contracted along the direction of movement?
 
I was just ragging.

IMHO, the ideas of length and time contraction breakdown for photons. But that's just an opinion with no justifying science behind it.

Edit: Sweet, that was my 100th post.
 
The photon's frame of reference is non-inertial and poorly defined, but the spacetime interval between any two events on the photon's worldline is indeed 0. You cannot really say that this interval represents either proper time or proper distance since it is neither timelike nor spacelike.
 

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