Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Something Out of Nothing

  1. Apr 25, 2010 #1
    Sunday night, Discovery Channel ran a program titled "How the Universe Works." The program explained Big Bang theory, string theory, etc. One of the things mentioned was how the Universe (may have?) formed out of nothing. The narrator basically said one needs to take a "leap of faith."

    How was this conclusion reached? Thanks for your time.
     
  2. jcsd
  3. Apr 26, 2010 #2
    It may have to do with the singularity, since the laws of physics break at singularities.
     
  4. Apr 26, 2010 #3

    Dale

    Staff: Mentor

    A singularity is not the same as nothing. A singularity is more like everything at the same place.
     
  5. Apr 27, 2010 #4
    Tyep "A universe form nothing " into google video, watch Lawrence Krasu excellent lecture.
     
  6. Apr 27, 2010 #5

    marcus

    User Avatar
    Science Advisor
    Gold Member
    Dearly Missed

    Mathnomalous, be careful. I didn't watch this particular show but Discovery Channel is not known to be reliable. It may cause harm to your brain. :biggrin:

    I don't know any evidence that the U formed out of nothing, or any reason to take a "leap of faith".

    In some models (mostly from before 2005, fashionable back in the 1990s) time is meaningless back before 13.7 some billion years ago. In other models (mostly studied after 2005 or so) time extends back before that and there is no emergence from "nothing".

    Nonsingular cosmology has come into fashion since around 2005---people figure out models where a singularity (breakdown of theory) does not occur. No one thinks that a singularity occurred in nature---it just means a mathematical failure of a theory and you deal with it by fixing or replacing the theory.

    But Discovery Channel is probably still talking about "The Singularity" as if it really means something. I don't know what they talk about, whatever stimulates people and keeps their ratings up. They have to make money.

    A new book is coming out this year about today's research into models of conditions before the big bang. I don't like most of what I hear about it. They got around 20 top experts with maybe about 10 different models each to write a chapter. Reviewer copies have already gone out and the book has gotten praise from some prominent worldclass cosmologists. So hopefully this will impact the pop-sci outlets and Discovery Channel will get more up to date. I would guess they are about 10 years out of date at present, just my wildass guess.
    But even then it won't be too good because the new book, called "Beyond the Big Bang" really is unselective. From what I can see by looking at the online material and the table of contents it has a large proportion of what is, in my humble opinion, garbage.

    Interesting computer models that go back before the big bang are being run. Systematic variations and different cases are being explored. A serious attempt is being made to identify features of the CMB radiation that would result from various models and which might be detected by instruments now in orbit or which could be put in orbit. You may see some hard scientific results emerge in your lifetime.

    But at the moment the prevailing professional attitude is "don't hold your breath". Don't take "leaps of faith". And just personally I would add to that my advice: don't watch garbage media or take highly speculative untested stuff seriously. Especially if it is 10 years out of date :biggrin: but also even if it is recent! Wait until some of these nonsingular cosmology models have made some firm testable predictions and the predictions are being tested by actual instruments in orbit. Just my personal advice as someone who watches the quantum cosmology scene.

    If you want to sample the quantum cosmology/early universe literature at technical level, skimming to find parts you can understand without too much math, here's a link.
    http://www.slac.stanford.edu/spires/find/hep/www?rawcmd=FIND+DK+QUANTUM+COSMOLOGY+AND+DATE+%3E2007&FORMAT=www&SEQUENCE=citecount%28d%29 [Broken]
    It is all I can offer because I don't know any reliable up-to-date popularization.
    That link gets all the professional research in quantum cosmology that has appeared since 2007. You can change the date and other parameters and play around with the search tool if you want. Most of the papers are free PDF online if you click on the right thing. The influential ones are usually the ones with high citation counts. They have been cited often by other researchers. So I ordered the list by citation count to bring up the more important papers first.

    Oh. Einstein-Online has a modest amount of reliable up to date popularization of quantum cosmology. there is a link in my sig. their stuff is post-2005 and they are a reputable research outfit. einstein-online is their public outreach website. It's not a big effort, popularization is not their focus. But the site has a few brief essays.
     
    Last edited by a moderator: May 4, 2017
  7. Apr 27, 2010 #6
    Thinking that this total universe was at one time smaller than the volume of a neutron sure sounds silly to me. Sorry.
     
  8. Apr 27, 2010 #7

    marcus

    User Avatar
    Science Advisor
    Gold Member
    Dearly Missed

    Who thinks that? Does somebody claim that is the scientific consensus? I'm curious where you got that, what the assumptions, the model, what part of the universe they were actually talking about. Maybe you could look up your source.
     
    Last edited: Apr 27, 2010
  9. Apr 27, 2010 #8

    DaveC426913

    User Avatar
    Gold Member

    What I'm curious about is how you determine what is "silly".

    Do you have experience with Big Bang-like phenomena by which to compare the sensical and the nonsensical?

    Are you looking around at other universe-creations that were much more mundane and non-silly such that this one stands out?
     
  10. Apr 28, 2010 #9
    Is there any way you or anyone can conceive of time before our universe WAS? How can you proclaim something that is so far beyond our capacity to grasp is silly? That's a bit like saying that the notion of you not having memories prior to your birth is silly, because here you are. Anytime we consider endings and beginnings, it isn't intuitive or comfortable.
     
  11. Apr 28, 2010 #10

    apeiron

    User Avatar
    Gold Member

    It sounds like the standard idea that the material to start the big bang arose as a quantum fluctuation out of "nothing".

    http://en.wikipedia.org/wiki/Edward_Tryon

    Of course, quantum fluctuations would seem to have to arise out of some framework of existence. So not exactly nothing.

    There are in fact a range of options on how to view the cosmological question of how it all first arose. I've summarised them in this thread on vagueness (the option that remains the least widely known, yet for me easily the most promising).

    https://www.physicsforums.com/showthread.php?t=301514
     
  12. Apr 29, 2010 #11
    Vilenkin publsihed a paper in Physcial Review Letters showing how the unvierse can come out fo literally nothing, the only thing thats required to exiist is the laws of physics.
     
  13. Apr 29, 2010 #12
    It's pure speculation as to what happened "before" the big bang, or whether there even was a "before". It's not really accurate to claim that it was created from nothing, since you can never extract data which would reveal that fact.

    The ultimate origin is always out of reach by definition, so it's best to simply say "we don't know". What we do know is that what we can currently observe was created with high density of matter and energy, the density of which decreased over time.
     
  14. Apr 29, 2010 #13
    That is the best answer in my view. I can imagine AN origin point, but not an ultimate origin being understood. We aren't built to handle infinities of any sort.
     
  15. May 1, 2010 #14
    In these matters, I always find solice in a quote from the late John Wheeler offering a lovely but chilling paradox: "At the heart of everything is a question, not an answer. When we peer down into the deepest recesses of matter or at the farthest edge of the universe, we see, finally, our own puzzled faces looking back at us."
     
  16. May 2, 2010 #15
    Very good quote, yogi.

    Actually, I am currently watching the NEW show [on the Discovery Channel], the one with Steven Hawking, and he actually states the "out of nothing" line. But as yogi's quote expresses, the further back in time we speculate, the more our own puzzled faces look back. An idea may work mathmatically on paper, . . . and even up to a point in reality, but only so far before it begins to step across the line of "science fiction".

    I personally believe that the idea of "the big bang" will take its place among myths. That may be a bold statement, but I make it anyway.

    Updated to add: "time was not there before the big bang" . . . . at any time there is even a fraction of movement, time will always exist.
     
  17. May 2, 2010 #16
    If spacetime are a single entity, then time cannot exist alone as we experience it. If you reject BB/Inflationary cosmology, what is your alternative? M-Theory and Brane Cosmology? Other than simply betting on the future, what leads you to believe what you do?

    I believe that the universe is fundamentally understandable, if not by us, but that is a human limitation, and has no effect on reality.
     
  18. May 2, 2010 #17
    I recognize the 2009 PF Award for Best Humor.
    Seriously, that was good.

    You must have missed this thread I started a while ago.
     
  19. May 2, 2010 #18
    I don't reject an inflation as redshift seems to suggest. I just don't believe that taking it "back in time to a 'singularity' and big bang" is something that I can see as a reality. What IS reality will be,. . . even if we never reach the technological level to determine it.

    Oh, . . . just so you know, and because I am new on here, . . . . I do NOT hold to the idea of a "creator" making it all.
     
  20. May 2, 2010 #19
    I'm not trying to "gotcha!" or anything like that. If you did believe in a creator, I don't assume that would interfere with your view of physics. Only fundamentalists seem to have that issue.

    If I might, inflation and the CMB are a bit of a road map back to at least 380,000 years before some event began inflation. Beyond the impossibility of actually visualizing the universe in its entirety, or in a timeless singularity, what about the theory do you find hard to see as reality?
     
  21. May 2, 2010 #20
    The majority of my issue is with the singularity; the notion that all matter was within this point. I know that it is theorized that actual matter was formed afterwards, you still had to have enough of the building blocks for it.

    Of course, I could be a bit confused from my 5 day fever.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook