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Before the Big Bang

  1. Jun 5, 2009 #1
    I've heard Stephen Hawking and many other physicists voice their opinions on the issue of what was or what the conditions were before the big bang. Stephen Hawking says:

    "As far as we are concerned, events before the big bang can have no consequences and so should not form part of a scientific model of the universe. We should therefore cut them out of the model and say that the big bang was the beginning of time. This means that questions such as who set up the conditions for the big bang are not questions that science addresses."

    I understand what he is saying here, and I'm sure many of you share the same idea. I do as well, to an extent. However, I do have a criticism of Hawking for this statement. I'm unconvinced that pre-big bang questions should simply be pushed to the side. To claim that events before the big bang can have no consequences seems to forget that the big bang itself must have been a consequence of an event or some kind of "setup" before it.

    Perhaps this is due to my lack of knowledge as a whole about cosmology. I'm just curious who else on this board agrees that events before the big bang (whatever that may mean) isn't something that should just be pushed to the side.

    I hope that if this is something I shouldn't be concerned about, someone here can help me correct the error in my thinking.
  2. jcsd
  3. Jun 6, 2009 #2
    Everybody gets stuff wrong...Hawking has made many mistakes but that does not diminish his many successes. This is a mistake in my opinion unless what he is really saying is that based on Einstein's equations, events before the big bang have no consequences. That's because there is no causal connection between before and after the singularity of the big bang in the classical realm. Of course that doesn't even make complete sense to me since Einsteins equations breakdown at the singularitye, big bang event.

    A much newer model than the big bang is emerging, via Paul Steinhardt and Neil Turok, a new "Cyclic Model of the Universe" which I just posted about under Cosmology. That does have a causal connection before and after repeated "bangs" because each cycle is finite in all respects.

    In my opinion, nothing should ever be pushed aside...no question should be dismissed....after all that's in large part how guys like Hawking and Einstein made such revolutionary discoveries.
  4. Jun 6, 2009 #3
    Thanks for the info. I think I've read briefly about this type of model, but I'm interested to find out more.

    I agree, well said.

    Thanks for your response.
  5. Jun 6, 2009 #4
    Yep, it's a booboo. It's like saying "Well physics breaks down after entering the event horizon of a black hole, so it's not worth considering". Yet Hawking himself has written so much about the physics of these areas.

    Personally, I think observation needs to catch up. It's very difficult atm to look far back into the past. We're limited really to the surface of last scattering/CMB and beyond that point in time. So much more has happened before then that we barely know about and have to rely on physics and theories to explain. Maybe once technology has improved we'll get closer and closer to our answers, but as of yet, I think our answers, options and theories are limited.

    Still, this doesn't justify putting it aside. All things should be looked into and with both open arms and scrutiny in a very scientific manner. When I heard about the possibility of branes and collisions of branes to generate big bangs, I really thought that was thinking outside the box, and I welcomed the idea. I may not have fully "believed" it myself, but I definitely considered it and lauded the creativity of the string theorists and others that came up with the notion.

    Gabriel, get to work on figuring it out! :P
  6. Jun 6, 2009 #5
    Yes, I agree. Even if we don't actually "believe" a suggestion, we shouldn't just push it to the side and leave it as if the suggestion were never there.

    I'll certainly try, haha :P
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