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Big bang or big joke

  1. May 9, 2004 #1
    I came upon this forum due to an article I read in Popular Mechanics entitled "Where time began" and a google search. I believe that the more you dwelve into detail the less you lose sight of the obvious. It never ceases to amaze me when scientists do all sorts of calculating, analysing, and formulating to lose all common sense and come up with the most dumbest of ideas. I know all of you out there are brilliant Eisteins but from a simple person here are some simple questions and ideas. Ok, riddle me this,

    If I look thru the HST to see THE "Big Bang", which direction do I look? I mean after all an explosion starts in one spot and tranverses outward. All elements from a "Big Bang would move outward but not all in the same direction.

    If there was a "Big Bang", then there would be galaxies, planets, and materials in one direction heading away from us and the same like in the opposite direction heading towards us all at diminishing speeds. We would also see the same moving perpendicular to own position. Beyond the point of origin we would see materials moving in an opposite direction. In order to understand what I'm saying here, picture each particle of an explosion in a 3 dimensional sphere from a point.

    With an ever changing universe of stars dying, materials and gases converging and stars being formed, how do we know this is the first time or the 1000th time.

    This is only a fraction of questions. Then there is the actual process of seeing this and saying you are lookin back in time. I believe when you look thru a telescope you are not seeing things in the past but merely as things are from a new point of origin. In essence, you are moving the HST or you or Earth somewhere within the point of visual light range. I understand that it takes light so long to travel from one point to another. But light also has so much energy. If this light-time travel theory is true, then in a few thousand years, all the light of the universe would be visible by the naked eye some night in the future. ( well, it really wouldn't be night with all that light) Not only that but tonight I should see a light source that wasn't there yesterday and the day after that and so on. Is there a time difference with light, yes. But only depending on where your origin is within the range of visible light and it's not that great of time change (universally speaking). The closer you look at a distant star or galaxy, the closer to real-time you are. I'm not ready to say that light or even audio travels are infinate. If they show me a picture from HST that shows the Earth with all it's continents in one mass, then I'll agree that HST can see into the past.

    Can HST show me an area of just gases and no stars and galaxies, where the spot of the BB started, and newly formed stuff sure. It's a simple exposion. But the beginning of time, the actual "Big Bang"? No.
  2. jcsd
  3. May 10, 2004 #2


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    This is a very common misconception caused by the name "Big Bang" not really being an accurate description of the event: it wasn't an explosion in the typical sense. It happened everywhere at once - every point in space appears to be moving away from every other point due to the space between them expanding. There is no center and no edge.
    This is fairly straightforward: if an object you observe is 9 light minutes away (the sun), what you observe it to do happened 9 minutes ago.
    If the universe were static and ageless, every line of sight would indeed terminate on the surface of a star. It isn't, so it doesn't. The Big Bang is the explanation for this.
    Huh? This has nothing to do with magnification, its a matter of how long the light took to get from a distant galaxy to the HST.
    No. Its light gathering capability isn't quite that good. It can see pretty far back though.
    What makes you think it should be able to? Its a great 'scope, but it it has finite capabilities.
  4. May 10, 2004 #3


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    Russ, has covered most points, so some of what I say will simply be a rehash what he's said:

    The idea of the bg bang as an explosion is an analogy, if you overextend this analogy you are bound to draw false conclusions. In big bang theory, the unvierse (or the observable universe at least) was a single infitely dense point; a singularity (big bang theory was not originally forumlated with a singularity in it, but Hawking and Penrose showed that an initial singularity was an inevitable result of big bang theory). Matter did not move out from this point, rather this point expanded, so as a result every point in the universe can consider itself equally to be this inital starting point and therefore it doesn't matter which direction you look whjerever you are in the universe.

    The speed of light is not a particularly difficult thing to measure and it has been measured many times and it is finite, so any object we observe we are essientially observing it's past state (a word of warning 'past' is a vey subjective wod in relativity due to the failure of simultaneity at distance), so in theory if we could build a powerful enough telescope we could point it in any direction and look back as far as the big bang. There are of course many practical limitations to this, but what stops us from doing this is the fact that the unieverse only became transparent to electromagnetic radiation about 300,000 years after the big bang. So any telescope that uses em radiation to observe objects can only see as far back as 300,000 years before the big bang.
  5. May 10, 2004 #4


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    If you were to actually study the details of the theory, you would see how it does make sense. Unforunately, the theory is poorly named (Big Bang) which causes a lot of confusion for people new to the idea. As described above, the Big Bang was not an explosion of stuff into emptiness. It was the rapid expansion of the entire universe from a previous denser state. Once you get past the misconception of a conventional explosion, things will start making more sense (although it is a very complicated subject).

    Feel free to keep asking questions! But rest assured that the "brilliant Einsteins" have not made such obvious blunders.
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