looking at the start of the universe

Discussion in 'Pseudoscience Archive' started by Captain Kremmen, Jun 20, 2007.

  1. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    I have heard recently that it is possible using advanced telescopes to see the universe as it was not long after the big bang. Can anyone explain to me how this is possible? It doesn't seem to make sense to me.
    If nothing can travel faster than light, then how can there be matter here for the light, or whatever it is we are detecting, to travel to. Did the universe and all the matter in it originally expand faster than the speed of light? Is the light from the big bang only now catching up? Or have I misunderstood something?
     
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  3. mathman Valued Senior Member

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    Light from objects x billion light years away shows us the objects as they were x billion years ago. Since the big bang was supposed to have been a little less than 14 bil. yrs ago, light from things that far away started at the time of the big bang. In practice, the earliest we can detect is the cosmic microwave background from about 300,000 yrs. after the big bang. Light from the first stars appears at a somewhat later time.
     
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  5. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    Thanks Mathman. You are the only one to reply so far. The question I am asking is not why we are seeing events that happened in the past.
    I can appreciate that light takes time to travel, so the event is delayed as far as we are concerned.
    The question I am trying to ask is difficult to formulate, but I'll try putting it a different way, and see if you can see where my reasoning has gone wrong.

    1. The light we are seeing which is billions of years old, originated from the big bang, and has travelled through space to reach where we are.

    2. The matter which this planet is made up of originated in that same big bang, so has travelled through that same space to reach where we are.

    3. How could this planet arrive here first, and the light 14 billion years later. That would mean that the matter of which we are made was either made seperately or travelled faster than light.

    See what I mean?
     
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  7. Sci-Phenomena Reality is in the Minds Eye Registered Senior Member

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    Only a human mind would fall to the lie that the universe had a begining that started as a "cosmic egg" that exploded into what we see today, it just mimicks the human embryo and growth to death story a little too closely.

    There is no edge of the universe and thus no center, and indeed there are massive "blank spaces" and "red shifts" which indicate some cosmic explosion, but time didn't begin with an explosion, its just always been. These massive universal "edges" of blank space are no more than telescopic limits unable to see any further into the infinite universe.

    To say the universe had a beginning and has an edge, is much like believing that the Earth is still flat, just because your human mind can't comprehend infinity doesn't mean you should believe that the universe has some "edge" you can fall off of.

    And to suggest that once you do get this mystical edge that you'll appear on the "other side" of the universe is equally mystical and absurd. If you believe in that part of relativistic theory I strongly urge you to go and join that wack group who still believe the Earth is flat.
     
  8. mathman Valued Senior Member

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    The simple explanation is that we are seeing light from things that went off in different directions from the stuff that ended up forming the earth.
     
  9. Walter L. Wagner Cosmic Truth Seeker Valued Senior Member

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    Chris:

    Good question, and you're confused because of a lot of misinformation out there, including even by some "physicists".

    The light we see from the cosmic microwave background is not from the moment of the "Big Bang", but rather from matter that coalesced into protons/neutrons [Hydrogen] that occurred some time after.

    Look at it this way. Everything originated from a single point in space-time (the Big Bang) in an infinite explosion of energy. Almost all of the matter/energy of the universe exploded away from the region that we call our space-time, i.e. the Milky Way galaxy region, leaving only a small residual amount behind, that coalesced into our Milky Way galaxy. Other regions coalesced into their own galaxies, and because they follow the same laws of physics, the galaxies look alike, etc.

    The galaxies that are now really far away from us left our region at a much faster speed than those that are nearby. The ones we see from really far away have very large recessional red-shifts.

    The matter that is the farthest away that we can see [via microwave telescopes] has the largest red-shift. That is the matter that blew away from us so fast that it recedes from us at about 0.999999c, giving it a red-shift of about 1,000. It has not yet coalesced into galaxies, as seen in our reference frame [though we presume it has formed galaxies much like our own within its own reference frame]. That is, light that it emitted [which is just now arriving here] when it had expanded and cooled to a temperature of about 2,700 degrees Kelvin [allowing the electrons and protons to couple into Hydrogen gas] we see as the equivalent of a black-body at about 2.7 degrees Kelvin. We see it from all directions, because it blew away from us in all directions.

    However, that is not all of the universe. The galaxies we see receding away from us in all directions, plus the matter that emitted the black-body background radiation that is receding away from us at about 0.999999c, is only a tiny fraction of the universe. Most of the matter of the universe blew away from us at even faster speeds; we just can't see it yet because it's beyond the region of the 2,700 degree K matter [in our reference frame], where the matter is so dense, and the temperature so high, that light travels slower than c (similar to light traveling slower than c when it goes through glass, etc.). As it cools and expands in its own reference frame, we will see it in our future, as our future black-body background emitter, though slightly cooler and more red-shifted than the black-body background emitter we see nowadays.

    In other words, the Big Bang was an infinite amount of energy that exploded from a single point in space-time, and our region of the Universe simply cooled down, allowing the formation of our galaxy, our star, and the evolution of life here on Earth.

    Hope this helps.

    Walter
     
    Last edited: Jun 24, 2007
  10. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    Thanks You.

    Thanks Walter, there's a lot to digest in that.
     
  11. Captain Kremmen All aboard, me Hearties! Valued Senior Member

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    Thanks Psi-P. Your viewpoint does clear up the problem. It does so by saying that there isn't a problem. If the universe is infinite and had no beginning, then there was no big bang. I am also a little concerned by the fact that the stars are evenly spread all around us. If there was an explosion from a central point, then there should surely be a shell of debris which would not result in galaxies randomly spread.
    I don't hold to any theory myself, but the big bang theory seems to be accepted by the majority. I'm just trying to get my head round it.
     
  12. (Q) Encephaloid Martini Valued Senior Member

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    A bit of a misconception there. The BB was not really an explosion, but more of an expansion with a period of rapid inflation.

    The universe is viewed as finite, not infinite. It is considered boundless instead. It is finite because there is a finite amount of mass/energy within it. It is boundless because although you may travel in any direction, you aren't really able to tell where you are in the universe, similar to if your entire world were on a line that was joined at both ends.
     
  13. Smellsniffsniff Gravitomagnetism Heats the Sun Registered Senior Member

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    Quite a big cosmic egg to begin with, with the radius 14 bill years you think right? Given that that egg in reall life was very small, the bending index for space would make the radiation that reach us low frequent, don't you think?
     
  14. wilgory Gandaffan Registered Senior Member

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    Chris,

    Check out these websites. You will find the answers to your question and the ones you will come up with after that. The FAQs(frequently asked questions) are a good place to start. The NASA website is a large one and you will need to use the search function to find the topic you want.

    http://www.astro.ucla.edu/~wright/cosmolog.htm

    http://math.ucr.edu/home/baez/RelWWW/

    http://www.nasa.gov/home/index.html

    These are reliable sources and you can avoid a lot of confusion that you find on the web if you check out the section "scientifically inaccurate claims" on the Relativity on the World Wide Web site.

    Good Luck,

    Wilgory
     
  15. Walter L. Wagner Cosmic Truth Seeker Valued Senior Member

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    Chris:

    I forgot to say: Welcome to SciForums.

    Q has it wrong. The BB was an explosion. The products of the explosion are moving away from us [we are located here in the Milky Way] with a very high kinetic energy. The farther away from us, the more mass there is moving away from us, and therefore even more kinetic energy because 1) the mass is greater than closer to us, and 2) the speed (recessional velocity) is greater. Eventually, if we look very far away, we see moving away from us a very large amount of matter that is essentially hot Hydrogen gas that has not yet coalesced into galaxies. We see it almost as if it were "frozen in time", that is we see it as it existed some 14 billion years ago. That is what our region of the Universe is believed to have looked like also - - very hot Hydrogen gas that is expanding and cooling. We see that matter receding from us at VERY high velocity [0.9999991 c], so not only is there a HUGE amount of matter in those regions of the Universe, but they have a HUGE kinetic energy relative to us.

    If you add up all of those kinetic energies, it is finite [though very large]. However, as I mentioned above, there is still more matter beyond that hot Hydrogen [with some Helium mixed in] gas, that is receding at an even greater velocity. The amount of matter beyond that hot Hydrogen gas [which emits what we call the cosmic background radiation, redshifted into the microwave frequences of the EM spectrum], which has at times been called a "Brehmstrahlung Opacity Wall" because we can't see beyond it, is infinite, and it is moving away from us at speeds approaching c.

    If one sums up all of that matter [which is also energy], and its kinetic energy, the sum is infinite; thus we live in a Universe that is infinite in mass/energy, but expanded into space-time so as to allow development of stars, planets and life.

    Hope that is understandable.

    Walter
     
  16. peta9 Registered Senior Member

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    You also don't know if it's infinite just because we can't detect those limits. That's like a mite thinking my rug is the universe. We can't even get out of our own solar system yet.
     
  17. (Q) Encephaloid Martini Valued Senior Member

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    Yes, to the uninformed, the Big Bang most definitely appears to be an explosion, especially when most artists depictions of it make it appear to look like an explosion. And of course, the next obvious conclusion is the notion that the "products" of that explosion are moving away from us.

    The Big Bang was the expansion of space, with all the objects contained within the universe (products) getting carried along with the expansion.

    The 'Redshift' observed is a result of the expansion and those objects getting carried along. This 'Redshift' would not be observed with the classical 'explosion with the resulting products moving away' notion.
     
  18. spidergoat pubic diorama Valued Senior Member

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    Walter's summary was very good. If I may add a more accessible layman's explanation.

    The early universe did not emit light. Contrary to how you might envision a huge explosion, there was nothing to see, no light could escape. By the time conditions were such that radiation was emitted, some parts of galaxy-forming regions were so far apart that light from their formation would not reach the other for billions of years. That's why we can detect this early radiation from so far away.
     
  19. (Q) Encephaloid Martini Valued Senior Member

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    As I wade further through Walter's summary, he not only was incorrect in the notion that the BB was, in your words, a 'huge explosion,' I see now that he is also incorrect about this:

    "We see that matter receding from us at VERY high velocity [0.9999991 c], so not only is there a HUGE amount of matter in those regions of the Universe, but they have a HUGE kinetic energy relative to us."

    Completely wrong. The universe is homogenous and isotropic making the distribution of matter/energy relatively smooth and not preferred to other regions.

    The reason we observe those objects receding is the fact that space is carrying along those objects as it expands. The distance between each object increases, hence the total expansion over billions of light years gives the appearance of distant objects moving at high velocities The redshift we observe is the photons being stretched as they travel through an expanding universe.
     
  20. fatandlazyfool Registered Member

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    Light started forming only 3 minutes after the initiation if I remember correctly. I don't think that the galaxies had started forming just then anyway.
    A theory for the universe as I've been explaining since my teens is the donut theory. Bear with me, the universe has no edge but bends on into itself. It appears that everyone has heard of the theory of a supermassive blackhole in the center of the universe/galaxies. What occurs in the center of the center of a blackhole? Nothing, right? It is the assymptote in which all math equations fall, it is dividing by zero. It is all matter turning into one piece of matter (or none). In other words, something becomes nothing. How does this occur when we don't appear to be gaining any energy but losing mass?
    To explain the entire universe we consider both extremes; the absolute center (the blackhole) and the edge of the universe. Now to give a picture of what the edge of the universe is, consider standing on the last planet while it rotates facing away from the second to last planet (or body mass), what would you see? Besides being infinite nothingness, one could in theory throw something out into that abyss implying something does exist in that apparant void. Now take the perspective of the object you just threw and throw something from there. If the object, x, you were trying to "throw" has greater mass than you and the new viewpoint object, y, then x would not move anywhere, but y could become a trajectory. Long story short, the piece of matter which is furthest from the center of the universe has to be smaller than the second furthest piece of matter from the center of the universe and so on and so forth.
    Another asymptote emerges, but this time it is the opposite of a blackhole where eventually no matter exists but the forces holding (or repelling) the last pieces of matter exist still but connected to where on the other side opposing the greater mass?
    Now, let's go back to the fundamentals: 4 fundamentals to be exact. With the 4 forces on matter (weak/strong nuclear forces, electromagnetic, gravity) all interactions take place within one of these catagories. Besides matter and these 4 forces, nothing else exists. A blackhole holds too much matter (and these forces) to allow any interaction to take place. The edge of the universe has too little either. There is an equal sign for both of these equations proposing a solution of zero meaning the edge of the universe and the center have something in common. The blackhole can hold no real form of matter but a great deal of force. The edge of the universe can hold no force but holds more mass than can be reasonably calculated (every piece of matter at distance x from the center of the universe with radius 14 billion light years). They are polar opposites...the energy of the edge of the universe is connected to the mass in the center. Round and round we go.
    That's crazy enough to try to consider, but what if each blackhole was connected to the universal forces on the edge of the universe? Wouldn't that create a superfluous equation, a never conceding energy source? Why would a universe need a beginning or end if energy was changing all the time from force to mass and back again?
    But I might have gotten off track.
     
  21. wilgory Gandaffan Registered Senior Member

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    Hello everyone,

    The term "Big Bang" was coined by a proponent of the "steady state" theory of the universe and was derogatory. It does not represent what General Relativity (GR) implies. GR breaks down before it can take us back to the beginning. All GR implies is that the universe was very small, very dense, and very hot. There are many models that use GR to describe the universe. The one most widely accepted by mainstream cosmologist is called the Lambda Cold Dark Matter model. Since the data we have contains variables this model allows for both an infinite(flat) and a finite(slight positive curvature) universe. This means we can not say which is correct when it comes to the universe we live in.

    The expansion of the universe isn't like that of an explosion. All of space-time is expanding at the same time, not from a single point. It isn't easy to grasp what GR implies because it uses non-euclidean geometry(the closest distance between two points is not a straight line thing). The balloon analogy is used to represent the expansion but leads to it looking like an explosion. It does do a good job of representing the finite yet boundless version in that a two dimensional observer can travel on the surface endlessly and not encounter an edge.

    I prefer the raisinbread analogy where the raisins represent the galaxies and as the loaf expands an observer on one raisin sees all the other raisins move away from it. While an observer on a distant raisin sees the same thing. The raisins do not expand due to the expansion of the loaf. Just as galaxies don't expand do to the expansion of space-time.

    When we see the distant galaxies moving away from us, all we are seeing is the observable universe. There is more to it than that. The known universe is much larger. An observer in a distant galaxy also sees all the galaxies moving away from it. If we restrict our view to the observable universe it is easy to see the expansion as being like an explosion. This also misleads some into thinking we are at the center of the universe.

    The answers to questions about things like the center, edge, age, size, and shape of the universe can be found on the websites I gave links to in post #11 of this thread.

    Wilgory
     
  22. andbna Registered Senior Member

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    fatandlazyfool:
    Photons had free raeign at 3 seconds in, however they quikly interacted with (were absorbed by) other particles so it actualy would appear very dark as far as light is concerned, untill about 370,000 years in, after which the universe had cooled eanough to allow electrons to form stable orbits around proton (hydrogen) which meant photons did not interact as well with them, thus forming the CMB.

    However, I strongly dissagree with your blackhole theory:
    False.
    Lets say an object of 6kg breaks into 3 pieces x,y,z momentum relative to center is 0kg*m/s
    x is 1kg y is 2kg and z is 3kg
    z is 'thrown' backwards with velocity of 5m/s momentum: 15kg*m/s back
    x and y thus go forward at 5m/s momentum: 15kg*m/s forwards
    total momentum: still 0
    x i then thrown backward 5m/s (relative to y) giving it an overall speed of 0m/s relative to the center, momentum: 0kg*m/s
    and giving y a speed of 7.5m/s relative to the center, momentum: 15kg*m/s forward
    z is unaffected and thus has a momentum of 15kg*m/s backward still.
    Total momementum: still 0
    Thus, the middle size peice: y eventualy gets farthest out, the biggest peice z is second farthest, and the smallest peice is closest to the center! Thus, there can there be a bigger peice farthur out.

    -Andrew
     
    Last edited: Jun 25, 2007
  23. Walter L. Wagner Cosmic Truth Seeker Valued Senior Member

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    Wilgory:

    Thanks for the input, and generally very correct.

    I do take exception with your statement that reads:

    "Since the data we have contains variables this model allows for both an infinite(flat) and a finite(slight positive curvature) universe. This means we can not say which is correct when it comes to the universe we live in."

    Only one of those "models" can be correct. A more in depth analysis yields the result that it is the infinite universe model that would be correct, though I will not attempt to present that indepth analysis here.

    As for the "expansion" of space, that is simply a mathematical construct to explain the recessional velocities we observe by red-shifts. The other galaxies [with the exceptions of those gravitationally bound to the Milky-Way and which are considered to be part of our Local Cluster] are physically moving through space away from us at a finite speed relative to us. Because they are receding from us, light that they emitted in our direction is red-shifted. We see them as they were when they emitted that light, not as they are "now" in our own reference frame. Any ET existing in such galaxies would see a similar picture as we see from the Milky Way - - other galaxies moving away from it.

    If we imagine a reversal of time, we compute that in the distant past some 14 billion years ago, all of the galaxies would be 'on top of us', that is, occupying the same volume at the same time. That is true for the matter that emits the black-body background radiation [2.7 K background radiation]. It too would be 'on top of us' at that same original moment in time. Thus, it is a 'snap-shot' of what the Universe was like when it emitted its light, which is so red-shifted due to the high recessional velocity that it is observed in the micro-wave frequencies rather than visible-light frequencies.

    To simply say that "space is expanding" is a mathematical construct that does not give justice to the fact that space is space, i.e. nothingness [with 'properties' allowing for virtual particles to pop in and out of existence a la Paul A.M. Dirac's reasoning, et al., etc.], and the other galaxies are physically moving away from us THROUGH SPACE.

    If we were to imagine an ET that might exist in a presumed galaxy that had formed, in its own reference frame, in the region of the Universe that we call the cosmic microwave background emitter [that matter that emits the microwave-frequency light, in our reference frame, that we call the 2.7 degree K background radiation], and it were to look towards the Milky-Way, it would not see our galaxy - - instead it would also see us as being in matter that was very hot and dense, receding away from it at very high velocity - - i.e. the way we were some 14 billion years ago. It would also be able to see parts of the Universe that we cannot see [parts that are farther still from us in our reference frame and we cannot yet see]. Likewise, we can see parts of the universe that it could not see.

    I do not like the "raisinbread" analogy, even though it does convey that all of the galaxies are moving away from each other. It also conveys the incorrect impression that they are all moving away from each other at the same general rate, which is not true, and also conveys the idea of an "edge" to the universe, which is also not true.

    The farther away other galaxies are, the faster they are moving away from us, in our reference frame. Anywhere in the universe would give the same general description, which is how/why the universe appears isotropic. This immediately implies that in the distant past, they were all on top of us at once, i.e. all matter compressed into a single point, which is the singularity point-origin of the universe.

    It truly was a Big Bang.

    Regards,


    Walter

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