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[Neruz]

The 'center' of the Universe (assuming such a thing is plausible) is no better a reference point than the current location of my left foot.

[Sean Mirrsen]

To space. The space space. Something the universe takes up.

Or, if following Ampersand's posts, the space portion of space-time.

[Neruz]

Sorry, i responded without reading your post properly. I've edited my post.

[Sean Mirrsen]

Heh. Well, the center of the universe has a tiny bit more practical importance than your left foot. Disregarding any possible occurence at the center, being located in it would effectively mean that the entire universe is moving relative only to you. By relativity, it'd mean you're the fastest-aging object in existence. Or wait, was it the other way around?

[Ampersand]

Space is infinite. Talking about it's center is like talking about the center of the surface of a sphere. It makes no sense and there is no point talking about it.

[Neruz]

Except that there is no reason why the center of the universe is a better point of reference than my left foot.

From the point of reference of my left foot, the rest of the universe is moving and it is remaining stationary. From the point of reference of the center of the universe, the same is true.


That's the entire point behind Special relativity; there is no universal point of reference, and no point of reference is innately 'better' than any other point of reference. They're all just points of reference.

Space is infinite. Talking about it's center is like talking about the center of the surface of a sphere. It makes no sense and there is no point talking about it.

We don't know if it's infinite or not.

[Il Palazzo]

What you're proposing Sean, is but another "historical" frame of reference, like chosing Earth or the Sun as the central point. While it makes sense, because historically something happened in the point of Big Bang and it even can make describing some stuff more elegant, just like the transition from geo- to helio-centrism did, it is by no means "special" according to special relativity theory. Not "special", as in, all laws of physics will be exactly the same in every other frame of reference one could choose.
(ninja'd)Note, that when you choose Earth, Sun, or Neruz's left foot as the center of the universe, all of the universe is still moving relative to you.

[Ampersand]

Perhaps a better way to put it is like this. If one stands on the surface of the earth and looks around them, they see a horizon. No matter where they stand, they will always seem to be at the very center, as the horizon is always the same distance away.

In a way, the same is true for the universe, which makes any discussion of where the center is, irrelevant.

Furthermore, the big bang was not an explosion that took place inside of the universe, it was an expansion OF the universe.

[Neruz]

It's more likely that calling the origins of the universe (assuming it has one) an 'explosion' is somewhat of an understatement.

[Innominate]

It's more likely that calling the origins of the universe (assuming it has one) an 'explosion' is somewhat of an understatement.

The universe itself - that which existed before the Planck epoch - is not necessarily observable. However, the observable universe definitely had an origin. This says nothing about previous observable universes, mutually unobservable universes, or anything else other than the observable universe. But it does mean that the oft-cited "criticism" of cosmology that "something can't come from nothing" is not relevant to the observable universe; we can't observe the unobservable universe (by definition) to verify that it doesn't exist.

As to whether explosion is an accurate word or not; you're spot on. An explosion refers to the rapid expansion of a volume within a space. The inflationary epoch was a staggeringly fast expansion of space itself. It's simultaneously not an explosion (in definition) and the mother of all explosions (in spirit ).

[Sean Mirrsen]

Special Relativity is as special as Special Olympics. It's considered special, yet it says no frame of reference is special. Double standards much? [/humor]

Anyway. The center of the Universe (note - Universe, not Space) is indeed only a factor if the universe is finite. Furthermore, if the universe is uniformly chaotic, then its center would be no better than any other point of the universe, even if it's finite.

But you have to factor something in. Let's presume for a moment that by some staggering violation of laws of probability, the center of the universe-creating explosion (calling it a "bang" is equally diminuitive, if you ask me) left a tiny empty space right in the universe's center of mass, large enough to put a ship in. All forces cancelling out, you would be at zero velocity and zero acceleration, motion of the entire universe would only be the motion of the universe, not your motion as part of the universe.

While not special by any stretch of the principles of special relativity or ambient energy, you'd still be in a universe's dead zone. Your position and speed would not have universe as a factor, unlike Neruz'z left foot, which inherits its motion from the Earth it stands on, which inherits its motion from the Sun it orbits, which inherits its motion from the Galaxy it is part of, which kinda shuffles forward due to anything the Universe did that scared it so much.

You could say in other words, that the point I'm speaking of is the average position of all matter and energy in the universe. Or the universe's center of mass. Presuming the Big Bang as the universe's origin, the average velocity of all matter and energy in the universe relative to that point would be close to zero.

But anyway, that point is purely theoretical. And yes, not really special unless you count those interesting qualities.

And finally, why does everyone use the words Universe and Space like they're interchangeable? What, the concept that the Universe exists within the Space is that impossible? It would even explain acceleration of the universe's expansion.

[Neruz]

It's more likely that calling the origins of the universe (assuming it has one) an 'explosion' is somewhat of an understatement.

The universe itself - that which existed before the Planck epoch - is not necessarily observable. However, the observable universe definitely had an origin. This says nothing about previous observable universes, mutually unobservable universes, or anything else other than the observable universe. But it does mean that the oft-cited "criticism" of cosmology that "something can't come from nothing" is not relevant to the observable universe; we can't observe the unobservable universe (by definition) to verify that it doesn't exist.

As to whether explosion is an accurate word or not; you're spot on. An explosion refers to the rapid expansion of a volume within a space. The inflationary epoch was a staggeringly fast expansion of space itself. It's simultaneously not an explosion (in definition) and the mother of all explosions (in spirit ).

Something tells me that calling the origins of the universe an Explosion is about as accurate as calling the origins of the universe a Duck

But you have to factor something in. Let's presume for a moment that by some staggering violation of laws of probability, the center of the universe-creating explosion (calling it a "bang" is equally diminuitive, if you ask me) left a tiny empty space right in the universe's center of mass, large enough to put a ship in. All forces cancelling out, you would be at zero velocity and zero acceleration, motion of the entire universe would only be the motion of the universe, not your motion as part of the universe.

Once again you leap to rediculous and illogical assumptions and use them as the basis for an argument. You really need to stop doing this while trying to engage in scientific discussion Sean.

While not special by any stretch of the principles of special relativity or ambient energy, you'd still be in a universe's dead zone. Your position and speed would not have universe as a factor, unlike Neruz'z left foot, which inherits its motion from the Earth it stands on, which inherits its motion from the Sun it orbits, which inherits its motion from the Galaxy it is part of, which kinda shuffles forward due to anything the Universe did that scared it so much.

In order to not be affected by the Universe, one would need to be outside the Universe. Given the definition of the word "Universe" this presents somewhat of a difficulty.

You could say in other words, that the point I'm speaking of is the average position of all matter and energy in the universe. Or the universe's center of mass. Presuming the Big Bang as the universe's origin, the average velocity of all matter and energy in the universe relative to that point would be close to zero.

In a word; no.

The Universe is expanding, like a circle on a balloon. The 'origin point' (assuming such a concept as any meaning at all, and this i doubt) would see the rest of the universe moving relative to it just as any other point of reference would.

And finally, why does everyone use the words Universe and Space like they're interchangeable? What, the concept that the Universe exists within the Space is that impossible? It would even explain acceleration of the universe's expansion.

You might want to go look up the definition of 'Universe' It's somewhat difficult to be outside 'everything'.

[Neruz]

I feel i should also add that 'Space' is just a system of measurement. Nothing more, nothing less.

[Sean Mirrsen]

General point: Space is the volume the Universe exists in. Space is the nothiness, finite or infinite. The Universe is everything else in Space - again, finite or infinite. This is my PoV.

I you draw parallels with the balloon, imagine a reverse balloon. Or a balloon in space, if you want. Space is the balloon, the air in it is the universe. It's not so much the air pushing against the balloon, it's the balloon allowing air to be as large as it can stretch.

[Neruz]

General point: Space is the volume the Universe exists in. Space is the nothiness, finite or infinite. The Universe is everything else in Space - again, finite or infinite. This is my PoV.

I you draw parallels with the balloon, imagine a reverse balloon. Or a balloon in space, if you want. Space is the balloon, the air in it is the universe. It's not so much the air pushing against the balloon, it's the balloon allowing air to be as large as it can stretch.

The problem you're running into here is that the word 'Space' means two different things. Space can refer to a three dimensional system of measurement, it can also refer to that stuff between planets and stars and other celestial bodies.