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A hypothetical and impossible solution to the origin of the Universe.

  1. Sep 25, 2009 #1
    A hypothetical and "impossible" solution to the origin of the Universe.

    To fully understand the principles by which light operates we have to know that if you look far enough away you can see the universe when it was much younger than it is now due to the amount of time it takes light to reach us.

    Because of this there is always the possibility that if the exact origin where the universe is expanding from is determined we could pinpoint the original cosmic anomaly that resulted in the universe whatever that may be. If you couldn't see whatever object that is it would have to be assumed that it happened to long ago that the light has already passed us and it can not be seen from here.

    In fact, now that I think about it in order for us to see the anomaly the expansion of the universe would have had to occur at a speed faster than that of light so it is impossible for us to see it from where we are now.

    If it was actually possible to travel at a speed faster than that of light, we could travel away from the center of the universe far enough that we could look back and see whatever it was that was at the origin of the universe.

    I know that this isn't a question or a theory more a statement of understanding from someone who just recently "comprehended" the effect the speed of light has on our understanding of the structure of the universe.
     
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  3. Sep 25, 2009 #2

    Ich

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    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    Please, first of all, learn the http://en.wikipedia.org/wiki/Cosmological_principle" [Broken]. We don't know if it really holds, but there is no evidence otherwise.
    So -without good evidence- don't speak about center or border of the universe: As far as we know, it looks the same everywhere. No border, no center.
     
    Last edited by a moderator: May 4, 2017
  4. Sep 28, 2009 #3
    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    Forgive me as I did not actually intend to dispute the current theories regarding the structure of the universe. It seems that if you could travel instantly to any location in the universe that you would easily verify or disqualify any theories regarding the origin and structure of the universe. I understand that this is currently impossible, but this ability would potentially dispel any unknowns we currently have about the universe given our limited vantage point.
    I will leave it at this, as any defense of instantaneous universal travel would most likely end up with a locked thread.

    I think that my intent with the first statement is that due to the fact that light travels at a set speed that if you traveled away from the lights origin far enough you would eventually be looking into the "past" so to speak.

    If the universe had a single starting point then it would have to have "center" wouldn't it. It is pretty obvious that it doesn't have an edge unless we are in some sort of cosmic fish bowl.
    It should be pretty easy to assume as well that if our universe was started with a single event, that this single event should be able to happen elsewhere. Is it not possible that if you moved far enough away that the universe in which we currently exist is merely one of many?
     
  5. Sep 28, 2009 #4

    Ich

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    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    Not necessarily. It's not all euclidean geometry in cosmology.
    Yes, everywhere. All wordlines of all possible observers would converge to a single event in a closed universe. They all were there.

    So if you're looking backwards in time to find the big bang, you find it everywhere. Or so it seems.
     
  6. Sep 28, 2009 #5
    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    We do find it everywhere. It's called the Cosmic Microwave Background Radiation.
     
  7. Sep 28, 2009 #6
    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    To see the "anomaly the expansion of the universe" as you put it, you couldn't see it not because its traveling faster than light, but because there was no light during the Big Bang. The background radiation we can see is when the universe cooled enough that light could exist. Also, in order for you to AT LEAST travel the speed of light, you need an infinite amount of energy. Light travels the fastest since it has no mass. There are lots of math that explains it beautifully but in short, since you weigh...something you can't travel the speed of light. :)
     
  8. Sep 30, 2009 #7
    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    I like this explanation as I have never heard it put this way before.
    Perhaps this should be under a different topic, but if light has no mass how could it be used to propel solar sails or in photon drives to provide thrust in a "frictionless" environment?
     
  9. Sep 30, 2009 #8
    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    Light is strange...even with no mass it still has momentum so it can impart its momentum on stuff like solar sails.
     
  10. Sep 30, 2009 #9

    Chronos

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    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    Apparently Ich has grown tired of these arguments. Photons have momentum. In fact, it is the only quantifiable property they possess.
     
  11. Sep 30, 2009 #10

    Chronos

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    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    Here is the hard part, can a massless particle have momentum?
     
  12. Oct 1, 2009 #11
    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    Does a photon cease being a photon when it stops traveling the speed of light?
    Perhaps the transformation that occurs when a photon impacts something generates a brief period of mass?

    Perhaps someone with a better understanding of physics can rephrase the question for me.
    As I understand it when light travels through a medium it is not actually slowed but "redirected."

    When lights color changes its speed also doesn't change the wavelength changes.

    So another question could be what happens to a photon when light is no longer generated?
     
  13. Oct 1, 2009 #12
    Re: A hypothetical and "impossible" solution to the origin of the Universe.

    the photon can't stop travelling at the speed of light, unless it garners enough energy to split into a particle - antiparticle pair. the photon itself is massless, therefore, while e = mc^2 doesn't apply to particles travelling at the speed of light, you can see that when it slows down it DOES obey this law, therefore it's energy is 0, so it can't exist.

    you're right about the being "redirected", what happens is that because the medium in question has many particles and molecules, when the photons hit them, they interact with them, for example bieng absorbed and then re-emitted, which is why on average the time taken to pass through is slower than the speed of light.

    light can't change it's speed (it's always travelling at the speed of light), however perhaps you're referring to c = lamda f, the relationship between speed, frequency & wavelength, i suggest you wiki it!

    keep on asking questions, physics is awesome
     
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