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Basic Big-Bang ?'s For First Thread

  1. Oct 5, 2012 #1
    Basic "Big-Bang" ?'s For First Thread

    I know this question is on the basic theory of the Big-Bang, but I'd like to propose simpler questions as my first thread starter (I literally just signed up to the site) in hopes to read the forums user replies and thus learning more about the different views, theories, and explanations. I feel I can learn much here, and so would love to see scientific minds such as yourselves answer simpler questions in relation to the most known and accepted theory, the Big-Bang.
    (To read the separate views and arguments made from answering questions that don't have any definitive proofs to answer with absolute certainty helps me see and understand another viewpoint besides the widely accepted, and typical one that is theorized and therefore defined "correctly" by the masses)

    1. How do we know space-time was created by the Big-Bang along with everything else?

    2. If space-time was nonexistent before the Big-Bang, then how did the Infinitesimal singularity which eventually blew up as the Big-Bang blow up? Wouldn't this singularity remain forever "paused" as a motionless point of infinite energy and mass suspended in a friction-less state? How could energy and mass exist this way if this is so?

    3. Why couldn't space and/or time have existed before the Bang? The Big Bang created everything within the universe but how do we know the universe itself didn't already exist; In 'time' the Big Bang blowing up and basically giving a universe full of empty space a vast amount of energy and mass?

    So my ultimate question (although feel free to answer or post on any or all of them) is could space and/or time have existed before the Big Bang?
     
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  3. Oct 5, 2012 #2

    marcus

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    Re: Basic "Big-Bang" ?'s For First Thread

    We do not know that---there are competing models of the start of expansion, more recent ones do not have a "singularity" and have time progression before the start of expansion.
    What you are saying about "created by Big Bang" sounds like one (not necessarily majority) view which may be going out of fashion.

    A doubtful assumption.

    It certainly could have existed. Many of the talks at the MG13 meeting in Stockholm (about the biggest regular conference that deals with cosmology and related matters) were about that very thing. Various ways it could have happened. Mathematical models going back before start of expansion. It sure is an active area of research.

    But scientists don't know all the answers (yet :biggrin:) that is why it's interesting!

    Of course both could have existed but what were they like? How were they behaving, according to what laws? That is what a lot of current research is about. The researchers model quantum gravity, construct computer simulations, and run models of early universe leading up to start of expansion, study effects, try to make predictions as to what closer examination of the ancient light ("cosmic microwave background") will find, and so on. There is research area called "Quantum Cosmology" specializing in very early universe. Do you want links to technical papers about this?

    Mr. Gray, don't misunderstand me and think that I am trivializing. We don't thoroughly understand geometry and how it interacts with matter----at extreme density, at extreme temperature, at extremely short distance scale, and factoring in quantum uncertainty and wave nature. This is a wonderful time in history to be watching scientists tackle major problems like how geometry and matter were behaving back around the start of expansion!

    the whole sky contains an enormously magnified picture of the early universe. Humans are only beginning to study that picture in detail and get a better understanding of space and time (or I should say geometry and matter) under the extreme conditions, from which the geometry and matter that we are familiar with arose.
     
    Last edited: Oct 5, 2012
  4. Oct 5, 2012 #3
    Re: Basic "Big-Bang" ?'s For First Thread

    I really enjoyed reading your open-minded answers. I truly believe this way about space-time as well and no-matter how many studies, lectures, or shows I watch about the Big-Bang, I can't help but nod my head everytime someone says, "Everything, including space and time was creating in the Big-Bang", as well as hearing Hawking's belief that there was no time for God to create the universe, yet, there was something which triggered the time-less pre-energy/mass expansion. Hmmmm, TIME Progression! At-least on a simpler, beginning note, time progression must have existed before the Bang. (Not saying I belief in a God or not, that wasn't the point. I merely meant how could one argue there was no time for something to create the big-bang, yet, there's some sort of progression for the big bang to...well...bang! I'd like to get more technical on this, so I'll continue to post on the topic when I can, and reply to your posts as often as a I can.
     
  5. Oct 5, 2012 #4
    Re: Basic "Big-Bang" ?'s For First Thread

    You are absolutely right about why physics, astronomy, and cosmology are interesting! :)
    If we had all the answers already I'm sure I would simply not study the subject because the mystery would be gone.
    One belief is also the quantum mechanics comparison. Quantum theory predicts that every particle will spend time as a combination of other particles in all possible ways. And that these 'virtual particles' can pop in and out of existence. If these two are true (which most the scientific community has known to be true) then quantum mechanics say our universe, as a whole, can pop in and out of existence (so the Big-Bang could have simply been a conservation of energy, beginning with one particle, and therefore that one particle could spontaneously become a pair of heavier particles (the so-called virtual particles) and so-on until BANG! This would not violate the conservation of energy law since all energy and mass were being conserved in a singular point of space-time (if one believes space-time was truly formed during the big-bang), building up, particles popping in and out and becoming other particles with even more energy conserved within each particle. This build up of pure energy would seemingly become unstable and heat up to billions of degrees creating what I like to refer to 'creation and annihilation matter particles' (The singular particle which become more, and heavier has also become heavy enough to form the first bits of matter which the big bang expansion filled space with these 'life' particles of matter which, along with EM waves, gravity and the strong and weak nuclear forces, the matter became the literal 'lego' building blocks of everything around us except for dark-matter and dark-energy. (Which Id love to hypothesis on another time within another thread lol)
     
  6. Oct 6, 2012 #5

    Drakkith

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    Re: Basic "Big-Bang" ?'s For First Thread

    I don't believe that quantum theories explain real particles as being made of virtual ones. To my knowledge they are in fact real particles, not virtual, and we cannot consider the universe to be able to pop in and out of existence. (Which doesn't even make any sense, as everything in QFT is within the universe)

    A word of warning. Your last post is starting veer off into the "speculative" and "personal theory" areas that are against PF rules. It's fine to ask questions, but before you try to make your own theory you need to make sure you understand everything well enough to do so. Which typically means you need a PHD in something like cosmology, since otherwise you really can't understand it well enough to form a viable theory.
     
  7. Oct 6, 2012 #6

    Chronos

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    Re: Basic "Big-Bang" ?'s For First Thread

    Agreed with drakkith on this being overly speculative.
     
  8. Oct 6, 2012 #7
    Re: Basic "Big-Bang" ?'s For First Thread

    I apologize about the speculations on that post. I don't fully condone what I said within that post either lol, I was just having fun with the topic by creating quick, possible scenarios to engage conversation since I am new to the site. I should have read the rules in-depth, I didn't know personal theories and/or speculations were against site rules. And I fully agree with you Drakkith about before coming up with theories I need to learn more about cosmology, among other things. I have immense fun studying these subjects and sometimes can get a little carried away.
     
  9. Oct 6, 2012 #8

    marcus

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    Re: Basic "Big-Bang" ?'s For First Thread

    Gray, I have nothing to add to the discussion of speculativeness, which I think is just a side issue. Probably you basically just want to learn about what's currently happening in the cosmology area. What gets on TV isn't representative, so it's good to have some window on the grubby reality.

    FWIW I'll offer a couple of links---to a major conference (MG13) and to a 4-week November workshop on "Fundamental Cosmology". The trouble is much of it won't mean anything..
    That's the problem, really. there is a kind of communication gap. You don't have science reporters attending these things and reporting truthfully to the general public in comprehensible terms.
    Maybe because it would just be too drab--they think (perhaps correctly) it wouldn't interest the public.

    Stephen Hawking's ideas are not featured at these mainstream events. I guess they are more "media-science"--provocative celebrity stuff. There is no flashy Kaku-Jazz at these meetings. On the other hand this is what I find really really interesting.. I think cosmology (especially what can be called "fundamental cosmology" is in a very exciting phase. Struggling towards a physical understanding of the what was going on around the start of expansion.

    "singularity" plays no positive role in this kind of investigation. "singularity" is just a word for failure.

    You can get these links yourself if you just google "MG13 stockholm". Big meeting held every 3 years. This time over 1200 scientiists took part. Every kind of research related to understanding the cosmos----computer modeling, quantum gravity, theoretical models, latest observations, dark matter searches, quantum cosmology, phenomenology (methods for testing different models) etc.

    Here is the list of those who chaired parallel sessions at MG13:
    http://www.icra.it/mg/mg13/par_sessions_chairs_details.htm
    It's informative because each chairman describes what his or her session is about, says what's going on in that particular field of research.
    Here is a bare list of parallel sessions (where following links can get you to brief summaries of talks):
    http://www.icra.it/mg/mg13/parallel_sessions.htm
    This list is convenient because no overviews. You can just jump to the session that interests you and click on links and get to the summaries of individual talks that made up the session.

    This may not communicate anything---might be boring and incomprehensible at first sight. But at least it is taking a direct look behind the popular media wall.

    that was this summer. Now there is something that could be a bit more interesting, and hasn't happened yet. It is a comparatively small November workshop on "Fundamental Cosmology" bringing together experts from a rather wide variety of fields, who are using a variety of approaches, different kinds of models trying to understand the same thing.
    It is potentially interesting to get these people face to face talking to each other. there is a German woman behind this named Sabine Hossenfelder. She is one of the four "organizers" listed for the workshop. She works in Stockholm and the workshop is to be held there, at her institute. The institute is called NORDITA

    Again this may be incomprehensible and boring. But I think it is important to look behind the popular-media mirage at what these people are actually working on so I'll get the link.
    Actually you can get it if you just google "fundamental cosmology nordita"

    Check it out. The workshop does not start till 5 November, so there is not too much information at the site now. But there will probably be more posted later. You can see the main themes listed. The broad outlines of what they're going to be discussing.
     
    Last edited: Oct 6, 2012
  10. Oct 6, 2012 #9

    marcus

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    Re: Basic "Big-Bang" ?'s For First Thread

    When I googled "fundamental cosmology nordita" I got interested in NORDITA. Here's some history:
    http://www.nordita.org/aboutus/history/index.php

    Apparently NORD means nordic and ITA originally stood for "Institute Theoretical Atomphysics" but that was in 1957 when Atomphysics was all the rage. Now they do Astrophysics, Biophysics, Condensedmatterphysics,...you name it.

    They have a really pretty building. Here is a snapshot:
    http://www.nordita.org/aboutus/

    The way this workshop is set up is, it seems to me as a distant onlooker, rather unusually intelligent and constructive. It has a shifting set of focus topics (over 4 weeks) and people can come for 1 or 2 weeks or they can come for the whole thing. And they will be meeting and talking to people they would not ordinarily encounter discussing things they would not necessarily hear about otherwise. People from different ways of looking at the very early universe will be crossing paths and learning about each other, that wouldn't ordinarily.
    The structure is relaxed---very little structure except for setting these four focus topics:

    ==quote==
    Scope
    Current cosmology provides a fascinating mix of a wealth of new observational data with deep conceptual problems still to be addressed. Several approaches in the general context of quantum gravity aim at a fundamental description of the relevant stages in the history of the universe, but none of them appears to be fully convincing and comparisons between different directions are difficult to draw. This workshop brings together a large set of experts, from both fundamental and phenomenological theory, in order to provide a snapshot of the current status and to focus future activities.

    Format
    This four-week long program will be composed of introductory lectures by experts in the fields and more specialized seminars on recent developments and open questions.

    The tentative plan is to cover the following topics:

    Week 1: Fundamental theories of space-time. Here, the main approaches will be introduced by some of the experts in the fields, with a focus on the resulting models for early-universe cosmology.
    Week 2: Cosmological and high-energy phenomenology. The various implications of fundamental theories for cosmology and high-energy physics will be discussed.
    Week 3: Cosmology and high-energy physics. In this week, a general discussion of the potential of cosmological and high-energy observations will be carried out.
    Week 4: Several combinations of topics covered in the previous weeks are possible to arrive at concluding statements. (Details of this week will be scheduled short notice, capturing those topics that have emerged as the most important ones.)
    ==endquote==
    http://agenda.albanova.se/conferenceDisplay.py?confId=2998

    I doubt that much (if any) time will be spent on more speculative stuff like "bubble universes" or "eternal inflation" or "something from nothing" or "anthropic multiverse". That stuff has gotten mighty old mighty fast.
    The list of participants is interesting especially if you know some of these people's work!
     
    Last edited: Oct 6, 2012
  11. Oct 6, 2012 #10
    Re: Basic "Big-Bang" ?'s For First Thread

    Thank you Marcus. I definitely don't think any of it as boring. I just began my first semester in college. Majoring in physics with a concentration on astrophysics and cosmology. (not easy at all of course, but I've never had so much fun within a classroom setting, which may sound "nerdy" but I'm loving it and learning something new everyday). I decided to also learn on my free time though by posting here, engaging in conversation, and using other site-tools to study and read from. I've been signed up here for less than two days and already I've learned from the responses posted by other members.
     
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