Can We Ever See the Big Bang?

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SUMMARY

This discussion addresses the limitations of observing the Big Bang and the nature of cosmic expansion. The light we receive from the Cosmic Microwave Background (CMB) originates from a redshift of z~1100, which means we see a time-delayed view of the early universe due to its expansion. Observers in the universe perceive themselves as the center, with the universe's edges being temporal rather than spatial. The CMB is opaque to photons emitted before approximately 380,000 years post-Big Bang, making direct observation of the event itself impossible, although neutrino and gravitational wave detection methods are being explored.

PREREQUISITES
  • Understanding of Cosmic Microwave Background (CMB) radiation
  • Familiarity with redshift concepts in cosmology
  • Basic knowledge of cosmic inflation and expansion
  • Awareness of gravitational wave detection technologies like LIGO and LISA
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  • Research the implications of Cosmic Microwave Background (CMB) radiation on cosmology
  • Learn about redshift and its significance in astronomical observations
  • Explore the principles of cosmic inflation and its role in the universe's expansion
  • Investigate current advancements in gravitational wave astronomy, focusing on LIGO and LISA
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Astronomy enthusiasts, astrophysicists, and anyone interested in understanding the early universe and the limitations of cosmic observation techniques.

imisscarl
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Hello all.

I'm no scientist, I just love reading about astronomy and watching Cosmos repeatedly, so please excuse me if the answer is super-obvious and known to everyone. I completely fail at math, so if anyone who answers could do it in plain english it would be GREATLY appreciated, equations will be utterly wasted on me I'm afraid.

I understand that when we look out into space, the view we have of stars gets older in relation to how far away they are due to the speed of light and the enormous distances it must travel.. some light we see is only a few dozen years old, some (not with the naked eye obviously) is billions of years old.

So my question is actually two-fold:

1: How can we see so far back? Did the Universe not expand equally fast at all points, and if so why not.. all points would face the same zero friction so they should all expand equally, right? How did we get ahead of the light we observe when we look very far out (or out at all for that matter)? Shouldn't the Galaxies basically form a bubble.. expanded from the Bang? Carl explained it as being a peculiarity of the 4th dimension / curvature of space.. that everyones viewpoint will be the same.. no matter where you are it will appear as if you're the center of reality and everything is rushing away from you.. but I just don't get it :T

2: Since we can look so far out / back, why can't we see the Bang itself? A new video was released recently showing a view of only 100 million years post-Bang (iirc). If we're that close.. why can't we see the Bang, wouldn't it just be a matter of looking a little further in that same direction and correcting our aim as info we receive gets newer instead of older, like homing in on a target?

Thanks for your time.
 
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1. We never really got 'ahead' of the light from the early universe. What we have, due in part to inflation and expansion, is a time delayed view of the early universe. The light we receive from the surface of last scattering [the CMB], is at a redshift of z~1100. When originally emitted, those photons were about as bright those emitted by an ordinary light bulb [around 3000 degrees kelvin]. Because we rushed away in such haste, they have been stretched out to near invisibility [2.7 kelvin]. And Dr. Sagan is correct, every observer in the universe thinks it is at the center - and they are correct. Every observer in the universe is at the center - and the furthest edge of the universe. The only centers and edges of our universe are temporal in nature, not spatial. The center lays in every direction 13.7 billion light years [observationally] from here. The edge lays zero light years distant at a point on the observers' retina. It takes a paradigm shift to think of the center as a boundary and its edge as a point, but, that is how the universe rolls.

2. The surface of last scattering [CMB] is opaque to photons, hence we will never observe photons emitted before around 380,000 years after the big event. Neutrinos and gravity waves are not EM particles hence either could be used to peer back virtually to the big bang. Neutrino 'telescopes' are highly impractical at present. Gravity 'telescopes' are, however, in play. We currently have LIGO up and running [re: http://media.caltech.edu/press_releases/13286] and LISA in the works. Both projects are discussed on the NASA web site.

BTW, welcome to PF! Aren't you glad you didn't just settle for a woowoo.com answer? We have a number of genuine scientists who hang out here and will cheerfully correct any errors on my part.
 
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