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Science

Before The Big Bang? 31

Psx writes: "The New York times has an interesting article discussing theories of what happened before the big bang." Pretty heavy stuff to think about.
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Before The Big Bang?

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  • My very own favourtie analogy, but as I understood this article it was saying that quantum cosmologists are moving on from this viewpoint, or perhaps circumventing it. In the moments from the Planck time to the inflationary epoch (roughly the first 10^-35 of a second) the structure of the universe is somewhat malleable (eg by inflation) but not as completely unknowable (without a full theory of quantum gravity) as it was before the Planck time. Some versions of inflation, for instance, would make our universe just a small region where inflation happened to stop, in a much bigger universe where inflation may be a permanent condition.

    At least I think that's what they're saying.
  • God i hate the NY Times...

    Whats a login/pass that works ? (wasn't there some created for slashdotters or something)...

    partners.nytimes.com doesn't work anymore.

    I got an account ("diskiller") but i dunno my password, and the email address goes to some account i can't log in to anymore, sigh.... i HATE these sites.

    Thank god i finally got my own domain for email.

    D.
  • Mind bending paradoxes that make sense if you only *stop* thinking about them are one of the reasons that I love physics.
  • I don't buy it.
    North of the north pole is a dimension, not a time. Yeah yeah, I know, before the big bang space and time were one. Well... that's why I don't buy it. At the TIME just prior to the big bang, all matter in the universe was in one spot, in one time.

    That's still a time and place. Not a non-time, or non-space, even if you want to claim "it doesn't matter" (pun intended_). Since time and space are both perceptions, you can't discount the fact that your perceptions may be wrong, no matter how close the mathmatical probibilities are. I mean really, flip a coin 100 times and mathmatically you should get a close approximation to 50%, right? Yet the tendency is to land heads up 72%. Go figure.

    Ctimes2

    PS - I don't buy gravity either. ;)
  • The very concept that not being able to measure something means it "doesn't have a value" is so ridiculous as to be laughable.
    If you have a theory that doesn't have this property, and explains observations as well as quantum mechanics, please let us know what it is.
    The arbitrary decision that a man is an observer but a cat is not is equally stupid and nonsensicle.
    Then why have you made that decision? This isn't necessary for the Schrodinger's Cat experiment.
    All they have are equations that seem to work.
    No, they also have observations. They have reams of observations which are inconsistent, for instance, with the theory that any particle has a definite position at any given time. (Remember, that is also only a theory.)
    --
  • Where is the crest of a wave after the wave has broken on the shore? What is its speed?

    Sort of depends on the shore, but generally speaking the wave is reflected with some attenuation (granted on the ocean shore the attenuation is large); thus, to answer your question, the crest of the wave is traveling away from the shore, at an angle normal to the angle of incidence, at its original speed.

    cheers ;-)
  • how do you explain the two slit experiment?

    Please. Did your school not offer physics?

    Single photons do not produce interference patterns.

    Statistics used to evaluate the behavior of large groups of particles cannot be used to determine the behavior of individual particles.

    But ... single electrons do produce interference patterns ... The dual slit experiment is not an inference based on a large number of particles, but something various people have actually done. It works: each particle appears to interfere with itself, meaning that each particle must pass through both slits at once, meaning that it does not have a single definite position at any given time.

  • userid: 12345678 password: 12345678
  • You're welcome.
  • No. The electron has some possibility of being anywhere until it is measured. That does not mean that the electron is everywhere
    So tell me...how do you explain the two slit experiment [colorado.edu]?
    --
  • The arbitrary decision that a man is an observer but a cat is not is equally stupid and nonsensicle (sic).
    Where did you get that idea about humans and cats from? Few modern physicists think that there is anything special about humans that makes them 'observers' but that cats aren't. Do you have any reference to a book that makes this claim or are you making this stuff up yourself? All they have are equations that seem to work. Interpreting them is another matter Tell me - what does 'interpretation' add that the equations don't provide?
    the very concept that not being able to measure something means it "doesn't have a value" is so ridiculous as to be laughable
    Where is the crest of a wave after the wave has broken on the shore? What is its speed?
    --
  • Photons fired one at a time eventually produce exactly the same interference patterns as light beams. The probability distribution of the arrival point of each photon in the two slit experiment is different to the sum of that from two individual slits.

    Please. Did your school not offer physics?
    I have a PhD myself. What about you? Sounds like you didn't understand what you learnt at high school. This is a crappy retort but hey - you started the crappy ad hominem attack because you're clearly too ignorant to respond in terms of physics.
    --
  • by SIGFPE ( 97527 ) on Wednesday May 23, 2001 @07:51AM (#204511) Homepage
    I might be oversimplifying, but I think Heisenburg meant that an electron could be anywhere, not is everywhere
    Unless they're historians as well no physicist could care less what Heisenberg originally meant. It's completely irrelevant to the practice of doing physics today.
    Percentages are nice, but Joe want's to know! So what does Joe do? He declared to the world that his cat is 50% dead.
    This is a completely incorrect picture. Joe tried damn hard to work with a probabilistic view of things for many decades. But you know what? - it didn't work. Joe didn't decide the cat was half dead because he had to know - he decided it because if the cat had a 50% chance of being dead it would behave completely differently to what is observed. Physicists aren't terribly afraid of probability (notwithstanding some comments to the contrary by Einstein). But probability theory failed. Simple experiments that can be repeated easily simply can't be explained by probability theory. And if you examine some books on physics you'll find that physicists are still using probability theory to describe plenty of physics - just not the parts that are better explained using superpositions of states.
    --
  • "What came before the Big Bang?" is as meaningless as asking "What is North of the North Pole?"

    asking "What came _before_ the Big Bang?" could just be taken to mean "What, if anything, is outside our universe?"? You may not be able to go north at the north pole, but you can go up...

    also, it is not just 'idle conjecture' to try to find out as much as is possible about our universe, it is natural curiosity to try to find out how everything works... we will never see the inside of a black hole, but people are still prepared to work for a life time to work out what happens inside one

  • In the worlds before Monkey, primal Chaos reigned.
    Heaven sought Order, but the Phoenix can fly only when its feathers are grown.
    The Four Worlds formed again and yet again, as endless aeons wheeled and passed.
    Time, and the pure essences of Heaven, the moisture of the Earth, the powers of the Sun and the Moon, all worked upon a certain rock, old as Creation.
    And it became magically fertile. That first egg was named "Thought".
    Tapaphuta (sic) Buddha, the father Buddha said "With our thoughts, we make the world".
    Elemental forces caused the egg to hatch. From it then came a stone Monkey! The nature of Monkey was... irrepressable!

    --
  • Physicists sound like they are starting to become mystics, rather than say there was a cause. They sometimes fall into linguistic traps of their own making.

    For example, by definiton, the universe is all that there is, and so how could there be anything else? The problem there is the definition, since maybe all that we see and extrapolate is NOT all there is.

    It would be a scary universe where it is populated by explosions that we experience as the big bang, but where the "big bang"is a mundane routine event, and is as common as stars and galaxies are here.

    Check out the Vinny the Vampire [eplugz.com] comic strip

  • Last week it was channel.nytimes... Don't know if that still works either.
  • btw... i tried partners.nytimes for the hell of it and it loaded.
  • This was the subject [slashdot.org] of discussion a while back on /. IIRC. Here's a link to a story from last month with pictures of what they think the early universe looked like.

    http://www.nsf.gov/od/lpa/news/press/00/pr0025.htm [nsf.gov]

  • From the article:
    Nevertheless, most cosmologists, including Dr. Guth and Dr. Linde, agree that the universe ultimately must come from somewhere, and that nothing is the leading candidate.
    ... isn't that beautiful?

    -Kraft
  • > And the Word was with God

    "with God"? Isn't that 2 words?

  • If you like physics, you'll love Zen Buddhism [ciolek.com]!

    Dancin Santa
  • Well, in fact, when an electron is measured, its localised. At time t after this localisation, the electron is everywhere, until it is localised again. So, Schreudingers cat is infact in the state dead and alive, until it is measured, then the funeral or the party can be arranged.

    No. The electron has some possibility of being anywhere until it is measured. That does not mean that the electron is everywhere. I may be in any number of places for all you know, but until you actually come by the office, you'll never know. I am not everywhere until you come by, I just have the possibility of being anywhere.

    Same with the cat. The cat has a 50% chance of being alive. It is not dead and alive simultaneously. As time rolls on, the probability that the cat is dead increases until there is a 100% probability that the cat is dead.

    Dancin Santa
  • how do you explain the two slit experiment?

    Please. Did your school not offer physics?

    Single photons do not produce interference patterns.

    Statistics used to evaluate the behavior of large groups of particles cannot be used to determine the behavior of individual particles.

    Dancin Santa
  • Photons fired one at a time eventually produce exactly the same interference patterns as light beams. The probability distribution of the arrival point of each photon in the two slit experiment is different to the sum of that from two individual slits.

    What I said initially: The electron has some possibility of being anywhere until it is measured. That does not mean that the electron is everywhere.

    These two statements are not contrary in any way.

    Dancin Santa
  • Let me clarify. I do not disbelieve that the particle-wave duality exists. What I do not believe is that each particle-wave is existent in all of space simultaneously.

    Dancin Santa
  • The slit experiment? I think th results of that experiment are due to movement of the device used to generate the light. If it isn't at absolute zero, it's moving, just a little. I think this movement is enough to create the same effect as a stream of particles.

    not directed at you: I don't appreciate being marked troll just because someone out there disagrees with me.
  • by ryants ( 310088 ) on Wednesday May 23, 2001 @04:57PM (#204526)
    I cannot take the time to login to the NY Times, but I have studied up some on cosmology, and most of what I read points to the following:
    • Since the Big Bang is the beginning of time, asking "What came before the Big Bang?" is as meaningless as asking "What is North of the North Pole?" "Before" has no meaning at the beginning of time, just as "North" has no meaning at the North Pole. Similarly, asking "What caused the Big Bang" is equally nonsensical, since for the Big Bang to be the effect of a cause, the cause would have to happen before hand.
    • Even if the Big Bang were not the beginning of time, any and all information from before the Planck time is forever lost, so there's no real point in discussing it anyways, except for idle conjecture and religious rantings.
    For anyone looking for a good primer on such things, I would highly recommend The Little Book of the Big Bang [chapters.ca]. Very readable.

    Ryan T. Sammartino

  • Thanx nublord!

  • Everyone knows that the universe began with an event known as the Big Gang Bang. As things cooled over time, many porno stars were formed, and that's why cyberspace is now filled with them. "Billions and billions," as Carl Sagen once said. Worlds revolve around these stars, and without them life would not be possible (or bearable). Scientists are now trying to determine whether the universe will expand forever, or collapse in on itself and finish abruptly.

    If you can think of a more plausible theory, I'd love to here it.
  • Can someone send me the contents of this article? Perhaps I am wierd, but I don't subscribe to NYT.

    -Jeffrey
    ticklejw@jtsoft.net

Perfection is acheived only on the point of collapse. - C. N. Parkinson

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