The Big Rip Theory

[IAstroViz]

This is an interresting one!

Oh damn,

 

This is an interresting one!

 

Sorry, I pressed enter to quickly,

 

Now the Big Rip happens when the expansion of the universe goes faster than the speed of light, (which is highly unlikely). All things will 'rip' apart and be torn into pieces. From gravity to all matter in the universe, everything will disapear in seconds.

It will be similar to this picture. Now for this to physically work... it doesn't. Nothing can be faster than light. Even photons that carry information can't go faster than ligth ©. But let's see in about 22 billion years, shall we?

[ajb]

The expansion of space is not constrained by Einsteinian relativity to be less than the speed of light. Anyway, what you need is the negative pressure coursed by dark energy (or whatever) to overcome the local attraction of gravity and the other forces of nature. This could happen as we are in a current phase of inflation and one that seems to be speeding up.

[IAstroViz]

Well yes you are correct, but I find Einstein's theory wrong about the start of the universe. That the universe is a cycle and continues on and on and on... But this accounts more to the Big Crunch theory... There was no "end" of the universe... (in my opinion)

[ajb]

Well yes you are correct, but I find Einstein's theory wrong about the start of the universe.

General relativity by itself says nothing about the start of the universe; by this we of course mean the classical singularity. We know that close to this classical singularity general relativity breaks down, it is no longer a good theory. It is expected that a quantum theory of gravity will regulate this singularity. Right now as we do not have a proper working theory of quantum gravity it is hard to say much more.

[IAstroViz]

Yeah... quantum gravity still exists... damn quantum physics... Love this site

[Phi for All]

Well yes you are correct, but I find Einstein's theory wrong about the start of the universe.

 

Perhaps you're basing your judgement on misinformation? Relativity doesn't attempt to explain the start of the universe. Einstein's work is hardly intuitive, but it certainly seems to work in the real world.

 

I'm wondering how Earth gets a pass up until the last half hour of the Big Rip. I thought it would only take a few billion years for our sun to go red giant, which will either burn us up or scatter all the planets due to the change in mass.

[IAstroViz]

Well, if we humans do create technology to exit our own solar system, we "could" survive the end of our planet... Or we just die off even before that because of the lack of resources...

[Phi for All]

Well, if we humans do create technology to exit our own solar system, we "could" survive the end of our planet...

I'm counting on that, but that isn't what I asked about. I was asking how the Earth survives another 22 billion years when Sol is expected to go red giant way before then?

 

Or we just die off even before that because of the lack of resources...

We have plans to use resources from space to help us increase our presence off-world, but this is getting off-topic for this thread.

[Mordred]

Your view of how the Big rip occurs is inaccurate. First off the big rip requires the cosmological constant to increase in energy density, sufficient enough to overcome the binding energy of gravity then the strong force.

 

Thus far their is no evidence of an evolving constant. So the big rip is considered highly unlikely.

 

 

Keep in mind the big rip was published prior to WMAP and Planck. Back then the exact average energy density wasn't known, we also didn't know the value of w

 

[latex] w=\frac{\rho}{p}[/latex]

 

The big rip requires phantom energy with equation of state w

[latex]w<-1[/latex]

 

The cosmological constant is currently

[latex]w=-1[/latex]

 

 

Here is the big rip paper.

 

 

http://arxiv.org/abs/astro-ph/0302506

Edited April 30, 2015 by Mordred

[IAstroViz]

Thanks for the info, I made an error, sorry...

[Mordred]

No prob glad to help