How are you able to "see" the big bang with a radio telescope?

Discussion in 'Astronomy, Exobiology, & Cosmology' started by garbonzo, Apr 5, 2012.

  1. garbonzo Registered Senior Member

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    Note: I know nothing about the Big bang Theory, really. xD

    I was watching Canadian news and they were talking about a huge project where they build a bunch of radio telescopes in a pattern and link them together to make one, kind of. They said they will be able to see, black holes, stars, radio frequencies, and even as far as the big bang itself. So how do you "see" the big bang itself when it happened so long ago? It it like how light travels at the speed of light and takes time to get to Earth, so we could see a star and it is already dead, because the light is just hitting us now?

    I know radio telescopes are different than things like the Hubble Telescope that sees light....
     
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  3. Grumpy Curmudgeon of Lucidity Valued Senior Member

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    garbonzo

    Light takes 13,7 billion years to travel 13.7 billion light years. And the expansion of space has stretched the light of the Big Bang so much it is now in the microwave spectrum. Radio astronomy uses the microwave spectrum, therefore, theoretically a radio telescope could see the Big Bang. We already have satelites that have observed the Cosmic Background Radiation which was released from the opaque Universe some 300 million years after the Big Bang.

    Grumpy

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  5. DaveC426913 Valued Senior Member

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    We see the star as it was in the past.

    Looking outward in space is looking backward in time.

    Galaxies 10 billion light years away are seen as they were 10 billion years ago (sort of, there's a lot else going on).

    So, if we look far enough back, we can see the first light after the universe stopped being opaque and became transparent to photons - about 377,000 years after the BB. it will look like a wall of radiation. Not entirely sure how they'll look past that.

    http://en.wikipedia.org/wiki/Timeline_of_the_Big_Bang
     
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  7. NietzscheHimself Banned Banned

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    The light from the start of the BB heads "straight" into nothingness. It is impossible to see clearly with anything. Yet extrapolating the direction of the traveling light will eventually lead you to a slight angle due to gravitational effects of the spherical universe. So after a while (billions of years) the light kind of makes a circle back away from the event horizon inside this black hole we refer to as the universe and heads toward the center. Since nothing can exist outside of this horizon it technically is still a straight line.

    Radio telescopes use elements which specifically pick up what we currently believe to be "the light from the big bang". But if you stare really really closely at anything you will realize that "it" is in fact made of light from the initial big bang. The light is just so dense, organized, and above all constant that an object appears to our vision solid and entirely different than such abstractions as "the big bang", a "black hole", or "light".

    Radio telescopes just pick detect the light as it is returning to it's original source.
     
  8. AlexG Like nailing Jello to a tree Valued Senior Member

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    Do you just make this up as you go along, or did you actually read this on some crank website?
     
  9. Boris2 Valued Senior Member

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    we can't see the big bang. furthest back we can currently see is the CMBR.
     
  10. Stryder Keeper of "good" ideas. Valued Senior Member

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    Guy's, your straying from the query of the initial poster into quibbling about your intellectual honesty, integrity or validity. Rather than spamming up the joint with quarrels about who-woo'd what, can't you just appreciate online sources that explore the question to it's fullest and point the OP in the right direction.

    perhaps:
    http://map.gsfc.nasa.gov/
     
  11. AlexG Like nailing Jello to a tree Valued Senior Member

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    Wrong. First of all, photons were not free to travel untill about 377,000 years after the BB. Until then, they were trapped by the charged cloud of ions which filled the expanding universe.

    Wrong. The light traveled in all directions once the recombination took place. There is no slight angle, and the universe is not spherical.

    Wrong. The universe is not a Black Hole, and there is no center.

    Wrong. Radio telescopes detect photons in the radio band of the electromagnetic spectrum. What it can detect, in addition to numerous radio sources, is the CMB.

    And this is so wrong it's just silly.

    So basically, everything you said was incorrect. Which is what I said before. But if you really want a statement by statement breakdown, there it is.
     
  12. NietzscheHimself Banned Banned

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    Excuse me for omitting irrelevant data to someone who knows nothing about the BB.

    Trapped by something which was dense and small enough to keep photons from exiting? Sounds in line with what I said previously.

    so if you look through a telescope in the summer and then again in the winter you would measure different distances to the end of the observable universe?

    There are no straight lines in nature...


    So it started out with the same properties as what other observable object? Read my first reply to your misguided quotations in this post...
    I don't remember saying there was a center unless you infer that that the universe as a whole is it's own center. Which you should have done if you had the ability to read.


    So the answer to the op's question is radio telescopes don't detect anything from the BB.

    The point is they use a very specific element to pick up this CMB. Not they pick up light in the nonvisable range which is a retarded point to make, because if they picked them up in the visible range uhh... we would see this false "white noise from the BB" with our own two eyes at a significantly less cost...ie. A pair of glasses at most.



    Ha. So very predictable... Let me guess your next post. You will still argue the universe didn't start as a black hole. Say something to the tune of "something can't be it's own center". Falsify the distances to the edge of the observable universe. Then prove that straight lines exist in nature when you can't even grasp the shape of the universe. To the last I will later inquire how you expect some of the light from the BB to return anywhere where a telescope can find it.
     
  13. DaveC426913 Valued Senior Member

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    So, garbonzo, as you have noticed, there are two types of responses on Sci Forums.

    There are
    - the answers generally accepted by the vast majority of scientists who do this for a living, with the support of, and under the watchful eye of, the entire scientific community and the rest of the world, and
    - the answers created by individuals whose scientific understanding is divorced from the rest of the science community and the mainstream sciences, and who back it up by saying they are their own harshest critics.

    Now, far be it from me or anyone else here on the board to tell you which you should listen to. That is entirely up to you. That's fair.
     
    Last edited: Apr 5, 2012
  14. Boris2 Valued Senior Member

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    there was nowhere for them to "exit" to.

    no. the cmbr is homogeneous and isotropic and is the "same distance" from us in all directions.

    it started as a singularity (open to debate) not a black hole. a black hole describes an object in spacetime. the black hole is the event horizon which is viewed from outside. so the universe is not like a black hole.

    to be pedantic everything we detect is from the BB.

    see above.
     
  15. NietzscheHimself Banned Banned

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  16. DaveC426913 Valued Senior Member

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    It is impossible by definition to be outside the universe, let alone outside the gravitational influence of it. This is basic cosmology.
     
  17. Gravage Registered Senior Member

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    Plus, universe cannot be a black hole, it's simply impossible for the universe to evolve from the black hole because of its hyper-intense gravity which would crush processes responsible for the universe evolution in the first place to sub-atomic levels (if not even below this).
    Cheers.
     
  18. Gravage Registered Senior Member

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    Well, it impossible to know if there is something beyond the visible part of the universe, because we didn't actually detect with telescopes the very beginning of stars, galaxies and etc...
    Cheers.
     
  19. DaveC426913 Valued Senior Member

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    True, but we're not talking about the Observable Universe here. We are talking about what was produced from the Big Bang, of which the OU is only a portion.

    NH wanted to know what the entire universe would look like "if you could get outside it". It is a nonsensical question by the definition of the words.
     
  20. Gravage Registered Senior Member

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    That's true, but also it's still questionable if the invisible part of the universe is created in the big bang or not, it could easily be that is some outside space as well, but we can't really know, since this invisible part of the universe will always remain undetectable.
    Cheers.
     
  21. NietzscheHimself Banned Banned

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    That particular question devides those who believe the expanding universe has a front that constantly pushes outward from those that don't.
     
  22. Aqueous Id flat Earth skeptic Valued Senior Member

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    One of the puzzling ideas behind this is connected to the notion that spacetime is created in the Big Bang.

    I'm not sure is possible to imagine what the absence of spacetime really means. A lot of wiring has been done in the brain to give us spatial perception, and it may be next to impossible to deprogram it.

    But in order to understand how space is created out of non-space (anti-space?) - I mean, what that really means - makes it hard to understand how a front pushes out. In other words, there is nothing to push out into if there is no space beyond the front.

    When we talk about the absence of space we usually mean a dimensionless point. For sake of argument, assume a sphere, a balloon. The front is what you mean if you look from inside the balloon to the inside surface of its skin. But viewed from the outside, our balloon is dimensionless. It occupies no space, because there is no space outside of itself. It is a dimensionless point that paradoxically happens to contain (from our scale) vast space, energy and matter and is ever expanding.

    Another puzzling aspect of this involves the warpage presented wherever we look into an event horizon. If at every point in the sky we look far enough to see the early radiation of the Big Bang event, then are we not looking into an event horizon, that is, a collapsing light cone that distorts our perception of geometry? Space collapses there, so what could we possibly hope to learn about its geometry without a homogeneous spaceframe to render it by?
     
    Last edited: Apr 6, 2012
  23. AlexG Like nailing Jello to a tree Valued Senior Member

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    But you don't have to look far to see the CMB. It fills all of space. The microwave radiation is passing through your body right now. It's not an expanding wave front in distant space.
     

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