Why cant we see the light from the big bang ?

[abueljihad]

hey guys,

i started wondering, why can we find microwaves that get back to the start of the universe and cant see a light the gets back to the big bang ?

thanks :) .p

[ghwellsjr]

The microwaves that we see are the light from the big bang stretched out by the expanding universe to a much longer wave length.

[abueljihad]

thanks for the reply, can u help me find info about this subject on the web ? cause google is not really helping me right now :(

[ghwellsjr]

Have you tried CMBR?

[DaleSpam]

The CMBR is from much later than the big bang. But we can't see past it because the universe was opaque before then.

[GrayGhost]

The CMBR is from much later than the big bang. But we can't see past it because the universe was opaque before then.

The CMBR began at about 300,000 yr post bang, yes? When did EM come into existence, visible or not?

GrayGhost

[tiny-tim]

hey abueljihad! welcome to pf! :smile:

you could try "A primer on the physics of the cosmic microwave background" By Massimo Giovannini (2008), particularly Appendix 2 (free online, click here (http://books.google.co.uk/books?id=4ziIOYR1qZQC&pg=PA411&dq=microwave+redshift&hl=en&ei=Gw09TqyVMca38QO_h8iMAw&sa=X&oi=book_result&ct=book-preview-link&resnum=3&ved=0CDkQuwUwAg)) :wink:

[DaleSpam]

When did EM come into existence, visible or not?About 10^-12 s after the big bang

http://en.wikipedia.org/wiki/Quark_epoch

[DaleSwanson]

You may find this video (and the ones that follow it) interesting.
http://www.khanacademy.org/video/cosmic-background-radiation?playlist=Cosmology%20and%20Astronomy

[bcrowell]

About 10^-12 s after the big bang

http://en.wikipedia.org/wiki/Quark_epoch

Convince me...? I would think there would have been electromagnetic degrees of freedom that were active at all times.

[DaleSpam]

Sorry Ben, that Wikipedia link is as deep as my knowledge goes on this topic. I do not understand supersymmetry and symmetry breaking at all.

[Chronos]

The CMBR began at about 300,000 yr post bang, yes? When did EM come into existence, visible or not?

GrayGhost
Particle physics is not my forte, but, this what I surmise from the literature.
The photon is the carrier of the electromagnetic force. The EM force did not split until around 10E-12 after the big bang, but, that does not appear to prevent photons from being created sooner. Photons can be generated by electrons changing energy levels, or more importantly in this case, by particle - antiparticle annihilation. Electrons and quarks are believed to have came into existence during the big bang itself [electrons are fundamental particle just like quarks]. So, electron - antielectron and quark - antiquark annihilation looks like a viable mechanism for photon emission. So, it appears photons were being produced right from the get go [~10E-43 seconds after the main event], which makes sense. All of these primordial photons were, however, trapped until recombination [about 380,000 years after the big bang], so none of the 'original' photons are observationally accessible today. Here is an article that may help 'shed some photons' on the matter:
http://insidesu.syr.edu/2011/03/28/large-hadron-collider/