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Re: Outer Space Thread

Posted: March 18 14, 10:22 am
by Michael
jim wrote:
pioneer98 wrote:There is a major announcement that just came out this morning. A group of scientists from Harvard and the Smithsonian claim they have evidence of gravity waves that would have accompanied the Big Bang. Way over my head, but it says gravity waves are predicted by Einstein's Theory of Relativity but we never observed evidence of them until now:

http://www.thewire.com/technology/2014/ ... on/359234/
This is a pretty big deal actually, from a cosmological point of view. Not surprising necessarily, but as you pointed out something predicted by relativity and consistent with the big bang/inflationary model of the universe.

http://www.nytimes.com/2014/03/18/scien ... ml?hp&_r=3
This is just mind blowing. Multiverse.... wow. The universe is such a strange and wonderful place.

Re: Outer Space Thread

Posted: March 18 14, 10:30 am
by thrill
Michael wrote:
jim wrote:
pioneer98 wrote:There is a major announcement that just came out this morning. A group of scientists from Harvard and the Smithsonian claim they have evidence of gravity waves that would have accompanied the Big Bang. Way over my head, but it says gravity waves are predicted by Einstein's Theory of Relativity but we never observed evidence of them until now:

http://www.thewire.com/technology/2014/ ... on/359234/
This is a pretty big deal actually, from a cosmological point of view. Not surprising necessarily, but as you pointed out something predicted by relativity and consistent with the big bang/inflationary model of the universe.

http://www.nytimes.com/2014/03/18/scien ... ml?hp&_r=3
This is just mind blowing. Multiverse.... wow. The universe is such a strange and wonderful place.
If anyone is interested in learning about the multiverse theory, this is an awesome listen: http://www.radiolab.org/story/91859-the ... universes/

Re: Outer Space Thread

Posted: March 18 14, 11:36 am
by thrill
One of the scientists personally delivered the news to one of the founders of the Big Bang Theory.

This is awesome.
http://www.slate.com/blogs/the_slatest/ ... roven.html

Re: Outer Space Thread

Posted: March 18 14, 11:40 am
by go birds
man what a feeling that must be............

my question is, can someone explain to me in laymen's terms what exactly the significance of this, other than the obvious i guess.

Like what does it mean for the future (not to take away from the significance of the discovery)?

Re: Outer Space Thread

Posted: March 18 14, 12:46 pm
by jim
go birds wrote:man what a feeling that must be............

my question is, can someone explain to me in laymen's terms what exactly the significance of this, other than the obvious i guess.

Like what does it mean for the future (not to take away from the significance of the discovery)?
It's a good question. The Big Bang theory without the idea of inflation doesn't make sense. Inflation was introduced into the theory to explain why the universe is basically flat. Without it, the universe wouldn't look like it does, and probably wouldn't have survived very long - it would have collapsed back on itself. The significance of the discovery is an important piece of evidence - a "smoking gun" - that inflation happened. It means that inflation goes from an idea on a chalkboard to something with real with tangible physical evidence to back it up. It's not just theoretical now.

So it's a confirmation of the most important idea in the birth of the universe.

Re: Outer Space Thread

Posted: March 18 14, 12:56 pm
by pioneer98
From the NYTimes article:
The universe is not old enough for light to travel the 28 billion light-years from one side of the universe to the other
and
The theory proposes that, less than a trillionth of a second after the Big Bang, the universe expanded faster than the speed of light. Tiny ripples in the violently expanding energy field eventually grew into the large-scale structures of the universe.
I thought relativity says that the speed of light is constant and nothing can travel faster than light. OTOH they are saying relativity predicted gravity waves. These two things seem to be in conflict. So does this discovery verify relativity, or does it say that relativity is incomplete? Struggling with this one.

Re: Outer Space Thread

Posted: March 18 14, 1:46 pm
by jim
pioneer98 wrote:From the NYTimes article:
The universe is not old enough for light to travel the 28 billion light-years from one side of the universe to the other
and
The theory proposes that, less than a trillionth of a second after the Big Bang, the universe expanded faster than the speed of light. Tiny ripples in the violently expanding energy field eventually grew into the large-scale structures of the universe.
I thought relativity says that the speed of light is constant and nothing can travel faster than light. OTOH they are saying relativity predicted gravity waves. These two things seem to be in conflict. So does this discovery verify relativity, or does it say that relativity is incomplete? Struggling with this one.
Yeah this is a common and understandable misunderstanding. Nothing can travel through space faster than the speed of light, but with expansion space itself is expanding. Imagine a giant balloon, where the rules said you could only go c on the balloon itself, but the rules say nothing about the balloon blowing up faster than that. The blowing up of the balloon is space expanding faster than the speed of light.

Hopefully that made sense.

Re: Outer Space Thread

Posted: March 18 14, 2:04 pm
by pioneer98
jim wrote:
pioneer98 wrote:From the NYTimes article:
The universe is not old enough for light to travel the 28 billion light-years from one side of the universe to the other
and
The theory proposes that, less than a trillionth of a second after the Big Bang, the universe expanded faster than the speed of light. Tiny ripples in the violently expanding energy field eventually grew into the large-scale structures of the universe.
I thought relativity says that the speed of light is constant and nothing can travel faster than light. OTOH they are saying relativity predicted gravity waves. These two things seem to be in conflict. So does this discovery verify relativity, or does it say that relativity is incomplete? Struggling with this one.
Yeah this is a common and understandable misunderstanding. Nothing can travel through space faster than the speed of light, but with expansion space itself is expanding. Imagine a giant balloon, where the rules said you could only go c on the balloon itself, but the rules say nothing about the balloon blowing up faster than that. The blowing up of the balloon is space expanding faster than the speed of light.

Hopefully that made sense.
Yes, that helped. One of the pictures in one of those articles really helped, too. This one:
[SHOW]
Image

Re: Outer Space Thread

Posted: March 19 14, 1:18 pm
by go birds
pretty good explanation for us n00bs

http://io9.com/the-new-big-bang-evidenc ... 1547240512

Re: Outer Space Thread

Posted: March 19 14, 2:47 pm
by Vidor
Image