[Alejandro]

Alejandro asked the Naked Scientists:
   
I was wondering if we know where the center of the universe is?  And if not then how could we find out?
What do you think?

[Mike Gale]

The centre of the universe is wherever you find yourself. A person on the left can peer deeper into space in that direction than a person on the right. You're probably thinking of the Big Bang as an explosion in space at a specific time. It is really an explosion in time, which occurred simultaneously at all points in space.

[Bill S]

You raise some interesting points, there, Mike. The following responses may not even be relevant to the OP, but, as thoughts that just popped into my head, they may lead somewhere.

“The centre of the universe is wherever you find yourself.”

True, as long as you remember that this applies to the potentially observable Universe, and may not have any meaning in terms of anything beyond.

There is also the complication that you are at your centre, but for a distant observer, also at their personal centre, you may be on the “boundary” of their universe, so you will be moving away from that observer, possibly faster than c; and that observer will be doing the same, relative to you. 
 
“You're probably thinking of the Big Bang as an explosion in space at a specific time. It is really an explosion in time, which occurred simultaneously at all points in space.”

If time and space were created at the BB, then it occurred neither in space nor time.  Personally, I have a serious problem with that, but it is a feature of some Pop. Sci. books.

“…..which occurred simultaneously at all points in space”.

Obviously this is correct if, at the BB,  there is only one, very specific, point which contains all of space and time, otherwise simultaneity is relative, and cannot be thought of as occurring other than locally; but if the former were the case, wouldn't it solve the flatness problem, without needing inflation?.   

[PmbPhy]

Alejandro asked the Naked Scientists:
   
I was wondering if we know where the center of the universe is?  And if not then how could we find out?
What do you think?

The universe has no center. Asking where the center of the universe is, is akin to asking where the center of the surface of an infinitely flat plane is or where is the center on the surface of a sphere (hint: its not at the center of the sphere).

[sceptic-eng]

If we look outwards we find that the furthest away stars are red shifted the most.  So to find the centre we need to look for an area that is blue shifted as that is where future time light is coming towards us from.

[puppypower]

This is my own theory.

The universe at one time, was so dense, light could not escape. It began with all the matter/energy within a singularity that would impact space-time similar to the mother of all black holes. Space-time was so curved, the light of the big bang had to orbit the center of the universe, unable to escape outward. The result is the original light appears to come from everywhere.

The analogy is a large volcano that erupts and gives off smoke and ash. During the eruption we can locate the source of the smoke and ash. But as the smoke and ash enters the atmosphere, it begins to flow with the circulation of the atmosphere, until eventually the earth has dust and smoke all over the atmosphere. This does not mean infinite volcanoes erupted everywhere, but rather the ash and smoke moved via the atmospheric circulation.

Eventually the universe expanded to where the curvature of space-time became large enough for the light to escape the original light mixing orbit. This escaping light phase, is what we see connected to the oldest objects. This light is still following a curved path, but instead of the orbit of a planet, it became more like the orbit of comet with a long elliptical orbit.

The matter from which the energy was originally associated, is not in the same place as the energy. Energy can move at the speed of light, but matter cannot. Just like the volcano slowly moves with the crustal plates, the smoke and ash can move much faster via the atmosphere. The smoke can appear to be from everywhere at the same time, but the volcano does not go very far. The center is out there not too far from the original boom.

The question is, how would you play this backwards to figure out the center? How would start with ash all over the atmosphere and use that to figure out where the original volcano was? You can't start late in the game; uniform ash in the atmosphere, or else there will appear to be more than a single volcano. You need to go back into time before the smoke and ash becomes homogenized like with the cosmic microwave background.

One possibility is the universe has been shown to contain superstructure. At the superstructure level, the matter is not uniform, like the microwaves. The superstructure reflects an earlier look, since it the lagging matter that is not as homogenized as the microwaves.

[Bill S]

This is my own theory.

One problem I see with the volcano analogy is that it erupts into the pre-existing atmosphere. The experts assure us that there was nothing into which the universe expanded, so the centre is everywhere, and nowhere.

[PmbPhy]

If we look outwards we find that the furthest away stars are red shifted the most.  So to find the centre we need to look for an area that is blue shifted as that is where future time light is coming towards us from.

It's the galaxies which we observe to be red shifted. Not the individual stars themselves. Your theory about looking for blue shifts is incorrect. There is no such place in the universe which is at rest with the matter of the universe. Especially since your reasoning makes no sense.

If you wish to post your own theory then you must post it in the new theory sub forum, not here.