expansion of universe vs speed of light

[Luagsch]

hi guys, there is a question that bothers my little brain and i just don't get it.
astronomers and astro-physicists look up to the sky and try to look as far back as the big bang. what i don't get is how? this would imply that the universe expanded faster than the speed of light (asuming a circular expansion of the universe (like whan you throw a rock in a lake)), cause the light just hits us now. or that there re other wavelenghs that are slower than the universial expantion. if the light that was emited 15 billion years ago reaches us now.... (well hopefully you get my troubles concerning this aspect). anyone an idea?

 

[imported_Mike]

Originally posted by: Luagsch
hi guys, there is a question that bothers my little brain and i just don't get it.

under statement?

i kid of course

 

[BatmanNate]

Originally posted by: Luagsch
hi guys, there is a question that bothers my little brain and i just don't get it.
astronomers and astro-physicists look up to the sky and try to look as far back as the big bang. what i don't get is how? this would imply that the universe expanded faster than the speed of light (asuming a circular expansion of the universe (like whan you throw a rock in a lake)), cause the light just hits us now. or that there re other wavelenghs that are slower than the universial expantion. if the light that was emited 15 billion years ago reaches us now.... (well hopefully you get my troubles concerning this aspect). anyone an idea?

I'm not sure if I follow you, but if something was expanding at greated than the speed of light, the light would never reach us.

 

[conjur]

This should clear everything up for you!


But, it's maybe the astronomers looking at light from galaxies expanding away from us...away from what was the center of the big bang?

Lots of great questions!

 

[Hayabusa Rider]

Originally posted by: conjur
This should clear everything up for you!


But, it's maybe the astronomers looking at light from galaxies expanding away from us...away from what was the center of the big bang?

Lots of great questions!

There is no center of the Big Bang. As far as we know, space is isotropic.

 

[Hanpan]

You are correct in your conclusion. The laws of physics do not disallow for space and time to expand faster than the speed of light. IN fact the modern Inflationary big bang theory implies this.

Remeber it is the fabric of space itself that has expanded and therefore light has been streched. That is why once increadably high energy photons today show up as low energy microwaves. Their wavelength has been streched by many orders of magnitude as the universe expanded.

Also someone else touched on this, everyone is allowed to see themselves at the center of the expansion. The concept behind this is quite simple in theory but takes a bit of time to explain and requires an understanding of SR.

Hope this helps

 

[Dowfen]

Originally posted by: Hayabusarider

Originally posted by: conjur
This should clear everything up for you!


But, it's maybe the astronomers looking at light from galaxies expanding away from us...away from what was the center of the big bang?

Lots of great questions!

There is no center of the Big Bang. As far as we know, space is isotropic.

Exactly, you just have to think of space as expanding from no one center.

Of course, that's just the current theory.

Eric

 

[Luagsch]

Originally posted by: Hayabusarider

Originally posted by: conjur
This should clear everything up for you!


But, it's maybe the astronomers looking at light from galaxies expanding away from us...away from what was the center of the big bang?

Lots of great questions!

There is no center of the Big Bang. As far as we know, space is isotropic.

well that explains eveything. thnx a lot. now my noudle can go on idle again

@conjur: thnx for the site. some nice thingys there.

 

[Luagsch]

Originally posted by: Hanpan
You are correct in your conclusion. The laws of physics do not disallow for space and time to expand faster than the speed of light. IN fact the modern Inflationary big bang theory implies this.

Remeber it is the fabric of space itself that has expanded and therefore light has been streched. That is why once increadably high energy photons today show up as low energy microwaves. Their wavelength has been streched by many orders of magnitude as the universe expanded.

Also someone else touched on this, everyone is allowed to see themselves at the center of the expansion. The concept behind this is quite simple in theory but takes a bit of time to explain and requires an understanding of SR.

Hope this helps

yes it does:sun:

thnx a lot (initiate update of universal view.... process complete. crc correct)

 

[boggsie]

Originally posted by: Hanpan
You are correct in your conclusion. The laws of physics do not disallow for space and time to expand faster than the speed of light. IN fact the modern Inflationary big bang theory implies this.

Remeber it is the fabric of space itself that has expanded and therefore light has been streched. That is why once increadably high energy photons today show up as low energy microwaves. Their wavelength has been streched by many orders of magnitude as the universe expanded.

Also someone else touched on this, everyone is allowed to see themselves at the center of the expansion. The concept behind this is quite simple in theory but takes a bit of time to explain and requires an understanding of SR.

Hope this helps

what he said