Expert: Jayendra Upadhye - 11/22/2006

Question
How is it --that powerful telescopes and other devices are able to see ever closer ("95% of the way" by one

account) to the "Big Bang", which is supposed to be the point of origin for all energy and matter?

Regardless the space-warped path, nothing travels faster than light --and those very near-primal wave fronts we're

imaging, yet somehow we've managed to get "out here" --in time to catch that wave front --from "back there".

Thanks for considering my question.

Answer
Hi,
I have picked up this question from the "pool".
If you had addressed it to another expert, sorry for barging in.

But it is a very good question, and i felt compelled to answer to best of my knowledge.

You see, You are correct to a point.
(because you have left your own suggestion loud and clear, but "unsaid").

Meaning you effectively are saying that we should be "seeing all" all the time, without having to "look back" at our origins "far out in space...IF the bang happened and things travelled no more faster than the speed of light.

You are right ...you see the "first flash" of the bang is all pervading and "with us" (like the force of the jedii)..It is the Cosmic Background Radiation.
It bathes one and all..the galaxies, quasars ..everything!
And it has cooled to represent hydrogen at 3 deg kelvin approx. (no point in space is cooler than that).

But within moments of the bang, the flash (light as representing matter at a black body temperature)..began to cool down & soon went into the infra red (dark) area.

Those were the dark ages of the universe. Maybe a million years later, the first stars & proto galaxies began to emerge. There was light again.

But! in the intervening ages (& compounded by the inflationary nature of the very early universe), matter had already dispersed over great distances.

It is from this point on, that the looking back (in time) over great disatnces in all directions, began to happen.

We look back in time (across the megaparsecs) at that first glimmer when the universe emerged from the dark ages.

Whereas as you said rightly, the first flash is with us all ..all the time, and cooling even as we talk, as it approaches absolute zero.

That is the CMB. It never left us, it was there all the time and will be forever.

It will be the first thing in the universe to attain absolute zero deg kelvin..(rather as close to absolute zero as can be reached), an unbelievably long time from now.

Who knows? the galaxies themselves will redden and fade away by then?
Jayen