the big bang

Discussion in 'Physics' started by bradstormer, Oct 17, 2010.

  1. bradstormer

    Thread Starter Member

    Aug 6, 2010
    65
    1
    if we look far enough into outer space, would we be able to observe the big bang?
    its just a random question that came up during a long drive (ya a bit weird but i do think of that kind of thing all the time!)
    also i was thinking of the implications that would have if we could, since the big bang was where it all started, could we track ourselves back to a point, and see our own history unfold? or am i watching too much star trek? :confused:
     
  2. tom66

    Senior Member

    May 9, 2009
    2,613
    213
    Yes.

    For one, you can observe the red shift of the galaxies. These were the observations that led Hubble to conclude the universe was expanding.

    Additionally, cosmic microwave background radiation fits the big bang theory perfectly.
     
  3. bradstormer

    Thread Starter Member

    Aug 6, 2010
    65
    1
    so does that mean that theoreticaly we can find our planet, a long time ago be it, if we look in the right place and see some of our own history?
     
  4. tom66

    Senior Member

    May 9, 2009
    2,613
    213
    No. But when we look at the stars we are seeing them as they were thousands of years ago (of course for the closest star it's 22 light years so 22 years ago.) Some of the most distant stars discovered are almost 13.7 billion light years away, which would mean they are some of the earliest stars in the universe.

    I presume if some alien civilisation produced a giant cosmic mirror 10 light years away from us we could see our reflection as it was 20 years ago. Or something like that. Be back in a sec, off to build a giant cosmic mirror. ;)
     
  5. Markd77

    Senior Member

    Sep 7, 2009
    2,803
    594
    I was watching "the sky at night" and they had a related thing on light echos. Apparently astronomers have just seen a cloud of gas light up and they think the light came from a supernova which was observed directly on earth hundreds of years ago.
    Similar things happen with gravitational lensing.
     
  6. bradstormer

    Thread Starter Member

    Aug 6, 2010
    65
    1
    so the cosmic mirror idea isnt so crazy after all! with the correct gravitational lensing we could in theory see many years into our past? sounds pretty awsome, like that denzel washington movie where the solved crimes with it
     
  7. beenthere

    Retired Moderator

    Apr 20, 2004
    15,815
    282
  8. Markd77

    Senior Member

    Sep 7, 2009
    2,803
    594
    I think that where gravitational lensing has caused a double image, the light from one image can take longer to reach us because of a longer path, so we see the source at two different times (probably not a massive difference, but maybe days apart).
    The conditions for light from the earth or sun to be lensed back to us in a measurable way are probably in the realms of science fiction.
     
  9. PRS

    Well-Known Member

    Aug 24, 2008
    989
    35
    It seems to me that we should be able to see our planet, or at least our sun in the distant stars if we are actually looking at history when we see the starry night.
     
  10. sceadwian

    New Member

    Jun 1, 2009
    499
    37
    Actually, as far as I understand it, actually seeing the big bang itself is impossible, because whatever banged caused space to bang with it, space at that moment expanded far faster than the speed of light, every moment of existence space is expanding just a little bit more so things further away are passing outside the event horizon where the expansion of space is faster than the speed of light, no matter how far back we try to look we'll exponentially always fall short of seeing 'it' And the farther into the future we get the less of the currently known universe will still be observable, at some date (not easily computed) many exponential years into the future even subatomic particles will be 'alone' that's if, of course nothing else ever bangs again..
     
  11. Markd77

    Senior Member

    Sep 7, 2009
    2,803
    594
    The important thing is that we are looking into the history of far away stars. Someone on one of those stars could see us at some point in the past, but because we are looking out, we can't see ourselves (unless there is a big mirror out there).
     
  12. sceadwian

    New Member

    Jun 1, 2009
    499
    37
    Too bad the distance such mirrors could exists at placea us even at the pinnacle of our electromagnetic detection technology outside the ability to detect ourselves.

    We'll never know it all, or even a fragment of it, but trying to learn is a good thing, that much I believe in.
     
  13. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,728
    758
    Cosmic Mirror....I like tht idea. AAAH!!..we can look into our past but alas. what's done is done.

    Universe is mind boggling ....I donno where to look and where not to look.
    On thing I know is our universe is just 1.
     
  14. Newtonsapple

    New Member

    Oct 24, 2010
    6
    0
    UK TV has shown a" Horizon" program that recently talked to a think tank in Canada to ask how many of them now thought the big bang happened. Most raised a hand to disagree with big bang Theory. The program asked the best ten physicists, what they thought happened. They all had different Ideas from " The Big Bounce " to Multi-universe theory. Some thought the universe has always been here and we are just in an expansion phase, and after a while it will contract again,lol.

    Its was on the BBC Iplayer for a while
     
  15. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,728
    758
    I believe in the big bang, it is one thing scientists got right to some extent.

    But there won't be another big bang, and our sun will not run out. For earth will end sooner than tht.

    As for our universe being one. I cannot be certain but I can tell u tht this is just one.
    Another universe begins where ours ends. Yet there are few more where they came from.0
    We can never go to the ends of our universe. Infact no human can venture beyond this galaxy. we can look into them though, but we cannot be certain that how many is there at present. What we are looking at always what has happened, not what is happening.
     
  16. GetDeviceInfo

    Senior Member

    Jun 7, 2009
    1,571
    230
    I've enjoyed the 'big bang' theory for many years, however I don't discount other concepts. The problem I have with the bang, is that it implies a starting point, a reference in time. This is one of our shackles as humans, our engagement with time.

    Lately I've been liking the idea that all we concieve is but a cosmic gust in a raging storm.
     
  17. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,728
    758
    The Universe was formed for our cause
     
  18. sceadwian

    New Member

    Jun 1, 2009
    499
    37
    The big bang only implies a start to our perceived existance, doesn't mean there was nothing before, actually by my way of thinking it actually proves there was something before because something had to bang. Exactly what that was we'll probably never know all the details but more and more science is starting to show that everything that makes up our observable universe is only a tiny fragment of the true inner works of things at a fundamental level.

    There is a relatively large huff going on about laser interferometer used in an attempt to detect gravitons waves, when they started the detector up they found a noise floor several orders of magnitude above what they expected, although they're currently working on different experiments to try to figure out why one theory is that our percevied existence is actually closer in resemblance to a holographic projection than reality.

    Material sciences in the last hundred years have come so far it's going to be interesting to see how things develop in the next 25-50 years.
     
  19. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    8,728
    758
    Universe was indeed created from nothing. Thus that bang. like let there be light and there it was.
    Scientist have a long way to go to figure out who is behind this
     
  20. sceadwian

    New Member

    Jun 1, 2009
    499
    37
    If there was nothing, what banged? There can't be a big bang theory without something to bang, the current cosmological problem is the moments during the actual bang are... fuzzy at best, mathematically difficult in the extreme and essentially irrelevant to human existence as a whole.

    Science does not have to prove what banged to know that it did, only that there was some sort of a bang, anything further than that is speculation currently. There is no who, just what and why, we are the who.

    The rest is psychological.
     
Loading...