a question about the origins of the universe

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as I understand it, according to the Big Bang theory, the universe began when an object of dimension zero and infinite mass exploded. According to cosmologists there's no point asking what happened before this, as time and space came into existence at the Big Bang so there was no 'before'.

My question is - did the event have a cause, or does the fact that there was no 'before' mean that there can be no cause?

― MarkH (MarkH), Monday, 1 September 2003 15:38 (twenty-one years ago)

We can't know - if the universe really did start out as a singularity of zero width and infinite density, there's no way for us to calculate its state immediately beforehand. If, indeed, there was a beforehand.

― caitlin (caitlin), Monday, 1 September 2003 15:49 (twenty-one years ago)

Well, essentially you're dealing with an object of collapsing dimensions, so any questions grounded in dimensional perception (pretty much anything) are more or less fruitless. Theoretically, a Big Bang can be the result of a Big Crunch (pretty much the reverse), so it could be a cycling event, wherein the universe expands and contracts, but this is entirely dependent upon gravity, mass, and several other factors.

I believe this all comes together in what is known as the Omega number, an equation number based on applying these factors as variables in the said equation. If the number is greater than 1, then there will be a Big Crunch. If less than 1, then the universe will infinitely expand. If it's exactly 1, then it will eventually reach equilibrium. Einstein's cosmological constant is somehow related, IIRC. And I think that the cosmological constant, omega number, and Hubble constant are all interrelated. So, yeah.

― Girolamo Savonarola, Monday, 1 September 2003 15:53 (twenty-one years ago)

http://www.site.uottawa.ca:4321/astronomy/index.html#omega

― Girolamo Savonarola, Monday, 1 September 2003 15:54 (twenty-one years ago)

I've come across the term 'Omega number' somewhere else: the ultimate uncomputable number; the probability that a given Turing Machine program will halt. I take it this one is *completely* different and unrelated?

― caitlin (caitlin), Monday, 1 September 2003 16:10 (twenty-one years ago)

the cosmological constant is now quintessence and probably means expansion will continue forever. infinite density is impossible, the universe is not likely infinite or else it would have infinite inertia.

― keith (keithmcl), Monday, 1 September 2003 16:13 (twenty-one years ago)

like me

― s1utsky (slutsky), Monday, 1 September 2003 16:15 (twenty-one years ago)

Surely infinite density is possible for something of zero size?

― caitlin (caitlin), Monday, 1 September 2003 16:16 (twenty-one years ago)

the cause thing is interesting. the line of thinking I was taking yesterday - on a long bus journey when I had lots of time to think - is that it *is* possible for something to have a cause when there is no 'before'...if you imagine life as beginning at conception rather than birth, then if you ask "what happened to you before you were conceived?" then the question is nonsensical, as there is no 'before' in your life, but if you asked what caused you to begin to exist then there is an answer - "the fertilization of an egg". But whether this has any bearing on the causation of the universe...well, I'm not altogether sure!

― MarkH (MarkH), Monday, 1 September 2003 16:21 (twenty-one years ago)

You correctly suss the fact that time is only meaningful in the context of space. Cause and effect describe properties of a universe where time and space have begun. There is no meaningful way for us to conceive of 'events' prior to the universe existing, or even within a universe of zero dimension and infinite mass. We can speak the words, but the words have no known referrants. It is one of our hard limits.

― Aimless, Monday, 1 September 2003 16:23 (twenty-one years ago)

Richard Feynman: "I think I can safely say that no one understands quantum mechanics...Do not keep asking yourself, if you can possibly avoid it, 'But how can it be like that?'...Nobody knows how it can be like that. If you think you understand quantum theory, you don't understand quantum theory."

Personally, I'm just impressed we've figured out as much as we have. We're doing pretty well, considering that our minds are made out of meat.

― Jesse Fuchs (Jesse Fuchs), Monday, 1 September 2003 16:44 (twenty-one years ago)

Re infinitude: infinite does not necessarily mean unmeasureable.

There are such things as infinite and bounded objects. For example, the equator is an infinite "line" - it keeps on going, but we do know how long it is. The universe is much the same way - it is infinite, but it is bounded. You're never going to bump into it's edge - you'll think that you're going straight, when in reality you'd be subtly curving your way around it. However, according to Hawking, if you try to circumnavigate the edge of the universe, it will take you until the end of time (or the Big Crunch) to come back to the point you started at.

― Girolamo Savonarola, Monday, 1 September 2003 17:16 (twenty-one years ago)

Bollocks, in what way is the equator infinite? You can keep going round it? Well yes, if you live forever. Which you and nothing does (considering that we almost certainly live in a universe which has a finite timespan this would be a impossible thing to do). So humans can imagine what the infinite might be (using the hokey ole biggest number +1 argument) but actually cannot deal with it in any useful manner.

This is prblematic because might of the mathematics used in science implicitally uses infitity as a useable (REAL) mathematical concept.

In the end - I believe we live in a finite universe with finite mass and energy and anyone who knows the letter E MC and squared knows this ends with E or M winning.

― Pete (Pete), Monday, 1 September 2003 18:27 (twenty-one years ago)

i thought it had been decided that all the matter/energy in the universe wasn't, as originally thought, contained in an area the size of a baseball, but in an area more like the size of a grapefruit

― Tracer Hand (tracerhand), Tuesday, 2 September 2003 03:45 (twenty-one years ago)

The universe is much the same way - it is infinite, but it is bounded. You're never going to bump into it's edge - you'll think that you're going straight, when in reality you'd be subtly curving your way around it.

What is outside ot these bounds? Nothingness? Does not compute.

― oops (Oops), Tuesday, 2 September 2003 19:04 (twenty-one years ago)

The boundaries of the Universe = math. Things which do not compute = outside the boundaries of the Universe.

IMHO

― nickalicious (nickalicious), Tuesday, 2 September 2003 19:11 (twenty-one years ago)

Well saying that something has boundaries implies that there are things outside of these boundaries. If the universe is defined as EVERYTHING, then what can be outside of these boundaries? My brain can just not comprehend the concept of nothingness.

― oops (Oops), Tuesday, 2 September 2003 19:13 (twenty-one years ago)

At least not until you die.

― nickalicious (nickalicious), Tuesday, 2 September 2003 19:15 (twenty-one years ago)

Nothingness is usually represented by a phenomenon, like a black hole (where objects get sucked in and supposedly fall forever). Therefore, the universe just continues on and on---until someone in the far future can prove otherwise

― Nichole Graham (Nichole Graham), Tuesday, 2 September 2003 19:17 (twenty-one years ago)

Correct.

I can not read this thread or I'll bust a lobe at the attempt to describe astrophysics without calculus.

― Mr Noodles (Mr Noodles), Tuesday, 2 September 2003 19:18 (twenty-one years ago)

What is outside ot these bounds? Nothingness? Does not compute.

exactly - it doesnt with me either, and ultimately it just comes down to having faith in the theory ( what you can understand of it) in much the same way as others have religious faith.

― jed_e_3 (jed_e_3), Tuesday, 2 September 2003 19:19 (twenty-one years ago)

Jeez, I'm pretty much cribbing Hawking and Kaku and people are yelling at me for the conceptual leaps they require? I'm not making this shit up people, I swear. Whether or not it is or isn't in fact true - it conforms to the current scientific thinking. Which can change.

Pete, the equator example is straight out of A Brief History of Time. I know it's hard to imagine that you can't even see the boundaries of the universe, but it's sorta like driving on a beltway - you're never going to come to the end of the road. The only difference is that it will take the entire history of the universe to figure out that you already passed an exit once before.

― Girolamo Savonarola, Tuesday, 2 September 2003 19:21 (twenty-one years ago)

What if the universe never did come into existence? No time, no space, no matter, no energy. What would there be? It seems like it HAS to exist because nothingness just doesn't make sense. (I know that's a pretty shitty argument)

― oops (Oops), Tuesday, 2 September 2003 19:26 (twenty-one years ago)

Well, if you get down to it, you can have a frozen universe, in which entropy slowly cools down everything until absolute zero (the average temperature of the universe now is only 3 degrees higher), at which point entropy stops and time stops. That requires an unending expanding universe (assuming no third-party sources of energy), which is why the omega number is so important. The only thing that can stop that is gravity, which would cause a big crunch, unless omega is exactly 1.

― Girolamo Savonarola, Tuesday, 2 September 2003 19:30 (twenty-one years ago)

That I can get my head around, since there would still be SOMEthing. Do we understand what gravity actually is yet? Is it the result of matter bending space-time?

― oops (Oops), Tuesday, 2 September 2003 19:40 (twenty-one years ago)

that's still a theory.

― Dale the Titled (cprek), Tuesday, 2 September 2003 19:42 (twenty-one years ago)

exactly - it doesnt with me either, and ultimately it just comes down to having faith in the theory ( what you can understand of it) in much the same way as others have religious faith.

no!

aaaaaaaaaaaaaaaaaaaaaaaaaah.
Brain explodes.

I knew I shouldn't have read this thread again. I knew it I knew it.
I love you all but this is killing me.

― Mr Noodles (Mr Noodles), Tuesday, 2 September 2003 19:45 (twenty-one years ago)

It all is, no? Is it the best one we presently have, though? I seem to remember hearing that many prominent physicists have recently discarded that theory for another one, but can't remember anything more than that.

(haha! mine brain explodes whenever I think about that too)(or did your brain explode because of my idiocy?)

― oops (Oops), Tuesday, 2 September 2003 19:47 (twenty-one years ago)

oops - what about death? Your consciousness ceases to exist, no? And that's very real.

― Mark C (Mark C), Tuesday, 2 September 2003 19:47 (twenty-one years ago)

time b/t opening this thread and onset of massive headache = approx. 6 seconds

― amateurist (amateurist), Tuesday, 2 September 2003 19:50 (twenty-one years ago)

[without reading new posts]
Sorry about my outbursts. Much like those who get annoyed at spelling mistakes and typos of which I make many, physics is my grammer.

― Mr Noodles (Mr Noodles), Tuesday, 2 September 2003 19:51 (twenty-one years ago)

that's still a theory.

Absolutely everything about perception, including perception itself, is a theory. What's your point? If you want to get all philosophical, you can argue that there is no objective truth. (And that's a conversation for a totally different thread.)

I don't have faith in theories; I only have faith that should ascientific one be incorrect, a better one will come to predominate in its place.

― Girolamo Savonarola, Tuesday, 2 September 2003 19:52 (twenty-one years ago)

the matter and energy that arranged itself to create my consciousness still will exist after my death.

― oops (Oops), Tuesday, 2 September 2003 19:55 (twenty-one years ago)

http://www.walgreens.com/dbimagecache/7502.gif

― amateurist (amateurist), Tuesday, 2 September 2003 19:56 (twenty-one years ago)

I know Noodles' feeling: it's impossible to even know where to start on this one.

― Martin Skidmore (Martin Skidmore), Tuesday, 2 September 2003 20:18 (twenty-one years ago)

but did you all spot his deliberate (i can only assume) mistake?

― stevem (blueski), Tuesday, 2 September 2003 20:20 (twenty-one years ago)

you mean mistakes?

― oops (Oops), Tuesday, 2 September 2003 20:23 (twenty-one years ago)

being and nothingness is the same thing. only different.

― andrew m. (andrewmorgan), Tuesday, 2 September 2003 20:32 (twenty-one years ago)

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