E_muse

So are you arguing that there was nothing prior to the BB? Are you suggesting that the universe just IS?

If there was no prior state to the BB, then what did the BB occur in? What was it that banged?

Where does it leave science if something as complex as the universe is stated as just being with no cause?

There will never be a straightforward answer to these questions and any conclusions rest partly upon metaphysical considerations.

However, if everything within our universe is caused in some way and contingent upon something else, why must I regard the universe as an exception?

E_muse

I understood that you do not believe in God.

The universe had a point where it began to exist .. the BB. I think we agree on this.

Again, I agree.

What are we able to understand about what caused the universe? That has been my question all along. Can we understand anything about it?

Again, I agree with you. However, time is a very strange phenomenon. However, if something exists that is beyond the universe and not bounded by time, can we argue that it must have been caused?

Of course it must be taken into account. It is the nature of this cause that is under discussion.

Does what caused the universe require a cause itself? If so, why? If not, why not?

I'm anxious to know what people think.

I would find it hard to believe that the universe wouldn't need a cause because all the evidence points to the fact that it had a beginning.

The question is, did what caused the universe have a beginning?

tronvillain

E_muse:
It seems a real possibility, though I personally would not attempt to argue for or against it being a fact.

If the universe simply exists, then the big bang did not occur in anything (in the same way that the universe does not exist in anything) and nothing "banged."

Well, it would leave science to study other things. There are only two options: infinite regress or brute fact.

You don't have to regard the universe as an exception, but as I just pointed out, you only have two options: infinite regress or brute fact. For the moment, the existence of the universe appears to be a brute fact, and without evidence I see little point in pushing the regress further back, whether for God or multiverse.

Technos

Well, the whole post has led to "begging the questions" of what is time, and what is the universe. Is this universe the alpha, the one and only to have ever developed? Is our big bang the first and last? If all the energy in our universe were to be scattered, would our "universe" still exist (I'd have to answer no, but the energy it is composed of would)? I've been intrigued with physics since I was a child, but I try not to take any theory to an absolute, but given all that we know, or at least think we know, about energy, there is no logical reason to assume that it could be created/destroyed unless you anchor down to one particular theory. I don't really like to get to far into theories personally, without sticking with what we know (or again, think we know) about atoms.

eh

[b[E-muse wrote,

So are you arguing that there was nothing prior to the BB? Are you suggesting that the universe just IS?[/b]

Nothing isn't something that exist prior to the BB. There is no prior. The universe just exists, unless you want to run into an infinite regress of events.


If there was no prior state to the BB, then what did the BB occur in? What was it that banged?

I though this question had been covered during the past 40 years. The BB is not an explosion in empty space. Rather, the BB is the expansion of space itself. So again, no outside of the universe means the BB is not occuring in anything.

The term 'big bang' was originally an insult intended to make fun of the theory. That is why it sounds odd.


Where does it leave science if something as complex as the universe is stated as just being with no cause?

Are the basic strings that make up our universe (energy) complex? If this energy is eternal (which it is, if there was no time when the universe did not exist) then no cause is required, nor is one possible. Science isn't going to suffer from this brute fact.

I also find it quite amusing that you would post an vastly more complex deity as the cause for a solution to this problem. Claiming God is non physical is a cop out.


There will never be a straightforward answer to these questions and any conclusions rest partly upon metaphysical considerations.

Except we already have evidence for a universe which doesn't need a cause, and zero evidence for a complex creator of this place. Sure God could exist, but it doesn't seem like he is necessary here.

However, if everything within our universe is caused in some way and contingent upon something else, why must I regard the universe as an exception?

Why would an eternal universe need a cause? If there is some fundemental energy that all posssible worlds need to exist, the universe is not contingent upon something else. Right?

E_muse

What do you mean by a real possibility? How are you using real here?

The no boundary proposal, which states that the universe is eternal and had no actual beginning, relies on quantum cosmology. However, such a universe only exists mathematically - there is no evidence for it.

If the universe does not exist in anything (some scientists hypothesize that it exists in a super-universe as a bubble) then what is it expanding into? If there is nothing outside the universe then you must demonstrate how 'nothing' can be a very real possibility because it is currently accomodating more of the universe as it expands.

Well, infinite regress suggests a prior cause to the universe. Whether this would have to be contingent could be discussed. However, I'm interested by the only other alternative that you offer.

Firstly, does it suggests that cosmology and all the money that has been ploughed into it are a waste of time and money?

Why is it that those most scientifically minded and most closely involved cannot leave it alone as brute fact and want to understand it better? Why is A Brief History of Time the best selling book on cosmology for all time?

How does accepting a complex structure as mere 'brute fact' promote scientific enquiry? Where would it leave evolutionary science if the same attitude was applied to complex biological systems?

Couldn't it be viewed as logically or intellectually inconsistent if the scientific community suddenly declared that the universe is a brute fact?

Well, such an attitude would kill scientific enquiry if adopted by those involved in the sciences.

The infinite regress suggests that what caused the universe must have been contingent. Why is this the only acceptable logical possibility regarding a possible cause of the universe?

E_muse

Well firstly, the general relativity model suggests that time, space, matter and energy all began at the big bang. All the known laws of science break down there. If you are saying there was no prior, then this is not a scientific statement under the general relativity model of the universe. The BB is the now accpeted model of the universe. It would appear from this model that the universe began to exist.

The initial singularity can only be removed by applying quantum theory to the original state, thus removing the singularity. However, science has not yet succeeded in combining quantum theory and general relativity into a unified theory. One such difficulty should be immediately obvious:

In quantum mechanics 'nothing' is not nothing in the absolute sense of the word. It contains waveform fluctuations that cause elementary particles to pop in and out of existence.

However, these theories are based upon observed pheneomena and therefore phenomena that exist within space and time. So applying them to the initial universe is not without its problems as one is possibly applying an effect to the initial universe and making it a cause. All the particles in the universe came out of the singularity described by general relativity.

So which model of an eternal uncaused cosmological model are you suggesting?

Some scientists have suggested that our universe is a bubble withing a super-universe. This makes the idea of its expansion less absurd. In order to conceptualize an expanding universe one must form the idea that something is accommodating it.

Indeed.

If general relativity is correct then the basic strings that make up our universe didn't exist prior to the BB.

But which model of an eternal universe are you referring to here? Hawing's no boundary principle?

A unified theory doesn't yet exist.

I haven't. I'm asking you to explain your own position.

What evidence are you referring to, I'm not aware of any? I know that such models exist mathematically. Hawking's model holds together using imaginary time. What sort of evidence is that?

All the evidence supports the BB model but little success has been had in unifiying this theory with quantum mechanics.

Under general relativity, that energy does not exist prior to the BB.

Quantum mechanicis is the only other theory that can be applied to the early universe in an attempt to explain it allowing the necessary energy to be introduced.

eh

Quoting E-muse,

Well firstly, the general relativity model suggests that time, space, matter and energy all began at the big bang. All the known laws of science break down there. If you are saying there was no prior, then this is not a scientific statement under the general relativity model of the universe.

That's exactly what the theory says. There is no 'before' the singularity, unless our visible universe is part of some bigger multiverse. The BB theory treats our universe as all there is, hence the no before statement. We can ignore the modern inflationary BB theories, which do allow for a multiverse, and pretend our universe is the first universe where time begins.

The BB is the now accpeted model of the universe. It would appear from this model that the universe began to exist.

This is becoming a matter of semantics. We can say time starts here or there, but we can't really say the universe begins to exist since there is no prior state.

The initial singularity can only be removed by applying quantum theory to the original state, thus removing the singularity. However, science has not yet succeeded in combining quantum theory and general relativity into a unified theory. One such difficulty should be immediately obvious:

In quantum mechanics 'nothing' is not nothing in the absolute sense of the word. It contains waveform fluctuations that cause elementary particles to pop in and out of existence.


AND.....

However, these theories are based upon observed pheneomena and therefore phenomena that exist within space and time. So applying them to the initial universe is not without its problems as one is possibly applying an effect to the initial universe and making it a cause


Yes, And????


So which model of an eternal uncaused cosmological model are you suggesting?

I've already explained it above. It's not some complex model, just the standard BBT. By definition, if the BB is where the universe starts, there is no prior state. No cause needed.

Some scientists have suggested that our universe is a bubble withing a super-universe. This makes the idea of its expansion less absurd. In order to conceptualize an expanding universe one must form the idea that something is accommodating it.


Too bad our poor human intuition cannot imagine the universe expanding without expanding into something else. If the universe expands into a super-universe, what is the super-universe located within?

[parts of the post sniped, as this is becoming repeatative]

What evidence are you referring to, I'm not aware of any? I know that such models exist mathematically. Hawking's model holds together using imaginary time. What sort of evidence is that?

The evidence for a universe? Well that's obvious enough. If the evidence for the BB convinces you, then you have your evidence for a universe that does not need a cause.

Under general relativity, that energy does not exist prior to the BB.

Yes, and?

E_muse

You suggest that the universe could not have been caused because no cause could have pre-existed the Big Bang singularity.

This is true unless of course, the cause of the Big Bang acted simultaneously with it.

Some have argued that all causes occur simultaneously as if all the necessary conditions existed for an event (e) prior to its happening at time (t) then the event would have occured prior to (t).

The need for a cause is metaphysical - as you stated earlier. From nothing, nothing comes.

The BB model at least tells us that the universe has changed state.

To say that there was nothing before the singularity is to say that nothing caused the universe to expand isn't it as that is where everything started?

Pretend? And what caused time to begin?

The reason that science treats our universe as all there is, is because it is unable to say anything about events prior to the Big Bang .. although some models have been put forward.

If you are saying that there was no prior state then you are saying that there was nothing to cause the Big Bang.

.. and it would result in circular reasoning.

Where the universe starts? Starts to what?

So nothing caused the universe to start expanding? Is that what you are saying?

There are different attempts at explaining the moment of creation itself (when matter emerged from the quantum vacuum). The standard BBT is incomplete. That is the whole point.

Would you agree that something outside of the universe would seem a logical necessity?

No, the evidence that would support the idea of an uncaused universe. Science needs something more than sheer belief.

Earlier you said:

Well, I certainly agree. Does this mean that we can draw certain metaphysical conclusions?

This is what the different scientific disciplines are trying to explain and why the official string theory website asks, "What came before the Big Bang?"

As you raised the issue of string theory, that is what I am asking you.

String theories have a problem. They only appear consistent in models of the universe that contain either 10 or 26 dimensions. Presumably, if one is applying Occam's Razor, scientists involved in the studies of these theories will stick to 10.

Obviously we only observe 4. Three spacial and one time. The arguement goes (as I understand it) that all the other missing dimensions are curved up into a space of very small size and so we don't notice them. However, this only emphasizes a lack of evidence.

Of course, this also begs the question, why, after the big bang, did the three spacial dimensions plus the time dimension flatten out and not the others? The only answer put forward by Hawking is to suggest the anthropic principle.

We couldn't exist in a universe with less than the four dimensions as we have them or in a universe were more of the alleged dimensions had flattened out. We wouldn't be around to observe it.

eh

Quoting again:

You suggest that the universe could not have been caused because no cause could have pre-existed the Big Bang singularity.

No I said IF the BB singularity represents the beginning of the entire universe, then there is no previous state for a cause to exist in. Remember that the word universe means everything that exists. How can existence itself have a cause?

To say that there was nothing before the singularity is to say that nothing caused the universe to expand isn't it as that is where everything started?

I don't know what the communication problem is here. English doesn't seem to be a very precise language, so even though we may be thinking on the same page, communicating ideas isn't always easy. There was no cause, is what I'm saying, not that a state of nothingness was before the universe.

Pretend? And what caused time to begin?

The reason that science treats our universe as all there is, is because it is unable to say anything about events prior to the Big Bang .. although some models have been put forward.

No, by defintion the universe is all there is. This includes any multiverse, Gods, etc. Are you thinking perhaps, about the visible universe?


Yes, And????


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.. and it would result in circular reasoning.


Only if you can't understand what is being writen.

There are different attempts at explaining the moment of creation itself (when matter emerged from the quantum vacuum). The standard BBT is incomplete. That is the whole point.

A vacuum is just a state of energy, and theories such as inflation only explain how our visible universe (with stars, galaxies, etc) came to be. We don't know if the universe is actually much bigger than our visible Big bang one, nor do we know exactlty how things happened but that isn't the point.

The point IS about whether a universe under the BBT requires an external cause. I say no, because again, the idea of something causing existence to exist is absurd.

Would you agree that something outside of the universe would seem a logical necessity?

No, I would say it is a logical absurdity. By definition, the universe is all that exists. Unless the universe is infinite in size, our intuition prevents us from being able to imagine how this can be. But it can't be any other way.

No, the evidence that would support the idea of an uncaused universe. Science needs something more than sheer belief.

It's not sheer belief. Again, I will say that the definition of the word universe is all that exists. How can existence itself have a cause? To say something outside of existence caused the universe, is to say something that doesn't exist caused existence. Absurd, wouldn't you say?

Earlier you said:


quote:
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Yeah, I know that nothing can't have potential for something. I was just confused on exactly what you meant. Nothing comes from nothing, and hopefully most members here won't disagree with that.
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Well, I certainly agree. Does this mean that we can draw certain metaphysical conclusions?

This is what the different scientific disciplines are trying to explain and why the official string theory website asks, "What came before the Big Bang?"


Again, I think it's just the weakness of the english language that is causing this misunderstanding. We can talk about what came before the big bang, if the big bang is not the start of the universe itself. Ekpyrosis is an example of that. So is Linde's self reproducing universe. But again, that wasn't the point.

As you raised the issue of string theory, that is what I am asking you.

String theories have a problem. They only appear consistent in models of the universe that contain either 10 or 26 dimensions. Presumably, if one is applying Occam's Razor, scientists involved in the studies of these theories will stick to 10.

Obviously we only observe 4. Three spacial and one time. The arguement goes (as I understand it) that all the other missing dimensions are curved up into a space of very small size and so we don't notice them. However, this only emphasizes a lack of evidence.

I mentioned string theory as a potential answer to the seemingly arbitrary nature of the universe. The theory is so elegant that it eliminates many of the arbitrary elements of the standard model. Tests to show whether or not string theory is on the right track, will be completed by 2005. Of course we don't know if string are the answer, but I brough it up to see how it would compare to 'God' as a possible answer to the fabric of existence itself.



Of course, this also begs the question, why, after the big bang, did the three spacial dimensions plus the time dimension flatten out and not the others? The only answer put forward by Hawking is to suggest the anthropic principle.

We couldn't exist in a universe with less than the four dimensions as we have them or in a universe were more of the alleged dimensions had flattened out. We wouldn't be around to observe it

Or maybe no other universes are possible? It may turn out that, no other types of worlds are possible at all, and showing this is one of the ultimate goals of string theory. Exciting stuff.