If the universe spontaneously came into existence, a big bang, all from a singularity, and all the matter is moving outwards from this point, and nothing can travel faster than light, so the first light in the universe should be heading away from us, why then can we see it? Or at least, why can human mechanical sensors see it?
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We may not be able to see the edge of the universe. It could be much larger than we can observe.
http://en.wikipedia.org/wiki/Observable_…
Conceptually in 4D spacetime, the location of the Big Bang is not one spot, but everywhere. We are still part of (or embedded in) the original "nugget." Think of the original energy (radiation) from the Big Bang as a gas that fills the entire universe. That gas is expanding and cooling adiabatically so that now the temperature of the gas is about 2.73 K.
http://en.wikipedia.org/wiki/Cosmic_micr…
http://en.wikipedia.org/wiki/Observable_…
Conceptually in 4D spacetime, the location of the Big Bang is not one spot, but everywhere. We are still part of (or embedded in) the original "nugget." Think of the original energy (radiation) from the Big Bang as a gas that fills the entire universe. That gas is expanding and cooling adiabatically so that now the temperature of the gas is about 2.73 K.
http://en.wikipedia.org/wiki/Cosmic_micr…
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First, we cannot say that the universe "spontaneously came into existence", simply that, by the nature of a singularity, we can never know anything of what happened before that.
Secondly, we cannot say that we are moving from a central point, but to appreciate this, you would have to be able to somehow conceptualize four dimensional space - which is possible, but difficult.
As an analogy, considering the 2 dimensional surface of a balloon in three dimensional space: imagine a point that could inflate like a balloon, but without limit. You could not relate one point on the surface of the inflating balloon to where the origin had been. The origin would have sort of expanded to be everywhere.
That is the way we thing the universe expanded, and is expanding. So that the origin has sort of expanded to be the 'everywhere' of the current universe.
This DOES take some thinking about.
Continuing the analogy: since we are all on the surface of this expanding balloon, we can indeed see light from the beginning of the universe: it has traveled across the surface of the balloon even as it has expanded.
Secondly, we cannot say that we are moving from a central point, but to appreciate this, you would have to be able to somehow conceptualize four dimensional space - which is possible, but difficult.
As an analogy, considering the 2 dimensional surface of a balloon in three dimensional space: imagine a point that could inflate like a balloon, but without limit. You could not relate one point on the surface of the inflating balloon to where the origin had been. The origin would have sort of expanded to be everywhere.
That is the way we thing the universe expanded, and is expanding. So that the origin has sort of expanded to be the 'everywhere' of the current universe.
This DOES take some thinking about.
Continuing the analogy: since we are all on the surface of this expanding balloon, we can indeed see light from the beginning of the universe: it has traveled across the surface of the balloon even as it has expanded.