How can astronomers see light from shortly after the big bang? How did we get "here" before the light that emanated from our "creation"?

  • $\begingroup$ Welcome to Physics.stackexchange! Unfortunately, we like questions based on established theories, and don't really encourage I-have-a-theory-please-check-it questions. Especially non-mathematically rigorous ones, Additionally, your question is very unclear in its present form. $\endgroup$ – Manishearth May 8 '12 at 2:50
  • $\begingroup$ Just a note for your future reference: Mathematical rigour is pretty necessary. Just an idea that is a bunch of arbitrary assumptions is extremely insufficient--If it was this easy we'd have had a TOE long ago. $\endgroup$ – Manishearth May 8 '12 at 2:52
  • $\begingroup$ Thank you for your comments as this is all "theoretical" pretty much just stuck in my head as I see it. Getting it down on paper In a more clear mathematically relavent form is in the works as we speak expect future edits as this is my first post I appreciate the "gentle" dissapointment in my sloppy approach $\endgroup$ – Argus May 8 '12 at 3:04
  • $\begingroup$ even if it's mathematically rigorous, it still may not be accepted, take note, since it's still a "I have a theory" question. Though you may have a chance, depending on your edits. :) $\endgroup$ – Manishearth May 8 '12 at 3:15
  • $\begingroup$ I think "I have a theory questions" can be tolerated but not encouraged, so long as one does not upvote/downvote either them or the answers, just let them be for the purpose of explaining why certain popular ideas are not mainstream science. This idea is a common misconception about the big-bang, that it fills space with light shooting out from a point. Only the galaxies in a Newtonian big-bang can be traced to a point (and the galaxy distribution is still isotropic at any time past the big-bang even in a Newtonian big-bang), not the light. The light doesn't converge back to a point. $\endgroup$ – Ron Maimon May 8 '12 at 3:41

You ask:

How can astronomers see light from shortly after the big bang? How did we get "here" before the light that emanated from our "creation"?

The very idea of "Big Bang" assumes General Relativity holds.

An analogue of this big bang can be a balloon that starts from a point and starts expanding. Our three space dimension universe has as analogue the two dimensional surface of this balloon. Everything we observe, the light going from point to point on the balloon is on that surface . The inside of the balloon is not a space where matter or photons propagate. Everything happens at the expanding surface.

Thus the light the astronomers see from the Big Bang, the cosmic microwave background radiation is the light coming from everywhere on our point on this surface. We hypothesize a time 0 for light coming to us because we see how cold the photons are, and calculate the red shift from the initial hot production of all those photons. But they are coming from everywhere ( the balloon analogue).

It is very anthropic in a sense to claim that we each of us are the center from where the Big Bang started :).

  • $\begingroup$ vNow that is an answer that makes sense thank you so much I was really about to leave and just chock this all up as a loss. No equations needed. Makes sense we are still "riding on the shockeave of the big bang so we are surrounded on all sides with the photons from that shockwave. Makes perfect sense super awesome answer still too new for a plus one but you have my vote $\endgroup$ – Argus May 8 '12 at 6:10
  • $\begingroup$ Argus you are new here and should have some patience for the answers. It may take a day or two to gather some answers that you can find useful. It is true as @RonMaimon said that mathematics is necessary for any progress in thinking and visualizing General Relativity solutions. This forum has all levels of questions and the people who answer are from theoreticians to amateurs. Wait and see. $\endgroup$ – anna v May 8 '12 at 6:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.