You should be shot for asking: how does matter move faster than light?

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The discussion addresses the misconception that matter can move faster than light, clarifying that in cosmology, the expansion of distances does not equate to ordinary motion. It emphasizes that galaxies are not moving through space but are instead receding from each other as the universe expands, akin to points on a balloon's surface. Photons travel at a constant speed, but the increasing distances between galaxies can exceed this speed due to the geometry of space. The term "Big Bang" is criticized for provoking misunderstandings, with suggestions for alternative names like "Big Balloon" or "Big Rescaling." Ultimately, the conversation highlights the importance of understanding cosmological principles to avoid confusion about the nature of the universe's expansion.
marcus
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We got some questions like: how did our matter get here ahead of the ancient light that is just now catching up? How can matter move faster than light?

In normal expansion cosmology there is a uniform pattern of expanding distances. When distances expand uniformly nobody gets anywhere. There isn't any thing or place you are approaching or getting closer to. You are not going in any direction. So it is not ordinary motion that a speed limit could apply to---it is a change in geometry. Motion has to have a direction.

Watch the toy model:
Google "wright balloon model" or go to
http://www.astro.ucla.edu/~wright/Balloon2.html
The galaxies are the white whirlers, basically they are all sitting still and all getting farther apart from each other.

On the other hand, you can watch the photons of light moving. They actually change their longitude latitude position. Each of the photons has a definite direction it is going. You will not see any galaxy move in any direction and certainly not move faster than a photon!

Of course you will see distances increase faster than the speed of light. Just watch carefully. The photons all move the same constant speed and the larger distances on the balloon surface grow faster than that.

So you should be shot for asking "how does matter move faster than light?" Obviously it doesn't!

For Anaximander's sweet sake, grow up! You people who ask questions like that. :biggrin:
 
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There's something in the FAQ about this, but the most shootable people don't seem to be willing or able to read the relevant FAQ. They just go blithely on and ask YSBSFA questions like "how did we get here ahead of the ancient light?"
 
The name Big Bang provokes these questions.
So maybe it's rather that this name for expanding universe model is simply stupid.

Let's call it Big Balloon or maybe Big Bubble. What do you say? :-p

But then again you get questions like - into what universe is expanding?

So I personally would prefer something like Big Rescaling. :biggrin:
 
zonde said:
The name Big Bang provokes these questions.
So maybe it's rather that this name for expanding universe model is simply stupid.

Let's call it Big Balloon or maybe Big Bubble. What do you say? :-p

But then again you get questions like - into what universe is expanding?

So I personally would prefer something like Big Rescaling. :biggrin:

The name was coined by Frank Hoyle - he was in disagreement with this theory - being an advocate of the steady state cosmological models - the term was indeed initially meant as derisery. The term just stuck.

What name we call the Big Bang has no real significance on the underlying mechanism - it is just a name, and the FAQs on this site very clearly outline the counterintuitive nature of said name.
 
I don't know, but I think if everyone was interested enough to ask any genuine questions about Cosmology from the simpleton to the genius, then mankind as a race would at last begin to show some promise. Saying that I can't thank ALL the contributors to this site enough for all their efforts, it is indeed very appreciated.
 
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