The Big Rip

Discussion in 'Off Topic' started by Scrapster, Jul 4, 2015.

  1. The Big Rip is a cosmological hypothesis about the ultimate fate of the universe, in which the matter of the universe, from stars and galaxies to atoms and subatomic particles, is progressively torn apart by the expansion of the universe at a certain time in the future

    If we look at the expansion of the universe, at first it was thought that, as things are expanding while objects have mass, the mass is going to be attracted to other mass, and that should slow the expansion. Then, in the late 1990’s, you have the supernova surveys that are looking deeper into space than we’ve ever looked before, and measuring distances accurately to greater distances than we’ve ever seen before. Something really surprising came out, and that was what we’ll now use “dark energy” now to explain, and that is that the acceleration is not actually slowing down – it’s not even stopped. It’s actually getting faster, and if you look at the most distant objects, they’re actually moving away from us and the acceleration is increasing the acceleration of expansion. This is actually a huge result.

    One of the ideas of trying to explain it is to use the “cosmological constant,” which is something that Einstein actually introduced to his field equations to try to keep the universe the same size. He didn’t like the idea of a universe changing, so he just kind of cooked up this term and threw it into the equations to say, alright, well if it isn’t supposed to expand or contract, if I make this little mathematical adjustment, it stays the same size.

    Hubble comes along about ten years later, and is observing galaxies and measuring their red shifts and their distances, and says wait a minute – no the universe is expanding. And actually we should really credit that to Georges Lemaître, who was able to interpret Hubble’s data to come up with the idea of what we now call the Big Bang.



    So, the expansion’s happening – wait, it’s getting faster. And now the attempt is to try to understand how dark energy works. Right now, most of the evidence points to this idea that the expansion will continue in the space between galaxies. That the forces of gravity, and especially magnetism and the strong nuclear force that holds protons and neutrons together in the center of an atom, would be strong enough that dark energy is never going to be able to pull those objects apart.

    However, there’s a possibility that it doesn’t work like that. There’s actually a little bit of experimental evidence right now that, although it’s not well-established, that there’s a little bit of a bias with certain experiments that dark energy may get stronger over time. And, if it does so, the distances won’t matter – that any object will be pulled apart. So first, you will see all galaxies recede from each other, as space starts to grow bigger and bigger, faster and faster. Then the galaxies will start to be pulled apart. Then star systems, then planets from their stars, then stars themselves, and then other objects that would typically be held together by the much stronger forces, the electromagnetic force objects held by that will be pulled apart, and then eventually, nuclei in atoms

    So if dark energy behaves so that it gets stronger and stronger over time, it will eventually overcome everything, and you’ll have a universe with nothing left. That’s the ‘Big Rip’ – if dark energy gets stronger and stronger over time, it will eventually overcome any forces of attraction, and then everything is torn apart.

     
  2. Interesting... this is making me flash back to watching Interstellar
     
  3. :lol:
     
  4. Whilst this could happen, there are plenty of other theories like the big crunch and the big freeze, I guess the questions is which will happen first..
     
  5. Scrap is a nub*insert moonface emoji*
     
  6. What if the universe isn't expanding, but it has always been the same size and matter is now just finally moving back into it? Which leads me to the theory that the universe is just a never ending cycle.

    I could explain it if you guys like.
     
  7. I'd rather you didn't :lol:
     
  8. At what point in this story did you realize that you liked men
     
  9. Good idea.
     
  10. Indeed
     
  11. From a thermodynamic perspective perhaps everything will eventually reach its most stable state by becoming gaseous and even atoms themselves will dissociate and be torn apart.. I guess this is partially what the big rip is based on
     
  12. Very informative, did not go too deep in the topic and also put simply enough for anyone to understand
     
  13. I would have gone so much deeper...
     
  14. I'm sure you would have done.
     
  15. There are lots of theories concerning the fate of the universe, all just as dawnting as this one.

    However I feel making these judgements when we havent seen any key changes in how our universe is behaving is jumping the gun a bit.

    Additionally, I feel that any theories that involve a catastrophic event such as the big rip are complete hog wash. The Big Rip goes by the assumption that the universe is expanding and always will be in an accelerated fashion... As if almost like the universe will never stop.

    Sure we have no evidence of it ever decelerating but it does not mean that it will not happen.

    I feel that no current theory of how the universe will behave will be accurate until a consistent series of changes in how the universe behaves, happens.

    However, I do not feel man kind will exist long enough to even witness these changes or even the big rip. Certainly not my lifetime...
     
  16. I'm partial to the Big Freeze myself..
     
  17. Agreed. I enjoyed reading this.
     
  18. Thanks.
     
  19. Tell us a story almighty narwhal