Speed of light? Or velocity of free space?

In summary, light travels at a speed of approximately 186,000 m/s in its natural environment, but when placed in a vacuum, its speed can change. However, the speed of light remains constant in between atoms, regardless of the medium it is traveling through. This raises the question of whether space, being a vacuum, can be considered a medium and have a velocity. Theorizing that space may have a unique makeup that allows light to travel at a consistent speed, regardless of its medium, leads to the idea that space itself can be considered a substance. However, this is still a topic of debate and further research is needed.
  • #1
dgoodpasture2005
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Light travels at approximately 186,000 m/s. as long as it is in its "natural" environment(space)... but put it in a vacuum and things change. So tell me then... Why do we call it the speed of light still? How about the velocity of space. So now... let's discuss this... please do not lock this thread, it is completely feasible.. and is not coming from a speculative pedestrian.. so i think it fits inside the S&D forum guidelines.
 
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  • #2
dgoodpasture2005 said:
Light travels at approximately 186,000 m/s. as long as it is in its "natural" environment(space)... but put it in a vacuum and things change.


How so? Space is a vacuum, or at least the closest thing we have to a vacuum. Even when light is interacting with matter it still travles at the same velocity. We only say the speed is different because the atoms absorb then re-emmit the photons causing a delay in the propigation.

Unless you can prove that the vacuum of space is made of some kind of "substance" I don't see how we can give it a velocity. What it the velocity of nothing?
 
  • #3
Yes, this is my point... when placed in an artificial vacuum light acts/interacts and travels at different speeds... let light flow in space and it flows back at 186,000 m/s. Space must be made of some substance.(energy/atoms/molecules, make up) Can you prove it's not? "...the velocity of nothing?" this is what I'm trying to get at. Right now it's nothing.. unfortunately i cannot blast off into space and do experiments.. I'd much like that :) The way light acts and loses its characteristics when placed in a vacuum(or taken out of space) would lead one to believe that, yes... space has a unique make up that gives light its unique properties in that environment. It's not light that is allowing light to travel at 186,000 m/s, it's space.
 
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  • #4
Theories are never complete, laws are made to be broken, the only thing that never changes is a constant, and the only thing constant is change.
 
  • #5
The speed of light in vacuum is ~186,000 mps. If a photon encounters something in space such as a hydrogen atom, it is absorbed, or absorbed and re-emitted. In the case that it is re-emitted, a propogation delay results but the speed in between atoms is still the 186,000... So in reality the speed of light is always the same.

Again, if you have science questions then please post to a regular physics forum. If you wish to post a theory, then please review the independent research posting guidelines.
https://www.physicsforums.com/showthread.php?t=82301
 
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1. What is the speed of light?

The speed of light is a universal physical constant that represents the speed at which light travels in a vacuum. It is approximately 299,792,458 meters per second (m/s) or 186,282 miles per second (mi/s).

2. How was the speed of light first measured?

The speed of light was first measured by the Danish astronomer Ole Rømer in 1676. He observed the differences in the timing of eclipses of Jupiter's moons and concluded that light must have a finite speed.

3. Can anything travel faster than the speed of light?

According to Einstein's theory of relativity, nothing can travel faster than the speed of light. This is because the speed of light is the ultimate speed limit in the universe.

4. Does the speed of light change?

No, the speed of light is a constant that does not change. However, it can appear to change if it travels through different mediums, such as air or water, which can slow it down.

5. How does the speed of light affect time and space?

The speed of light plays a crucial role in Einstein's theory of relativity, which states that time and space are relative and can be affected by the speed of an object. As an object approaches the speed of light, time and space begin to warp and change.

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