An Infinite Past?

[Leonhard]

Our universe is increasingly understood by cosmologists to be just one of an infinite number that make up a "multiverse; this notion is supported by solid physics and several models have been arrived at by physicists independently of each other. Hence, some form of multiverse is the most probable explanation of how the cosmos functions.

I don't think Smolin, Guth, Vilenkin or any of the others have ever argued that the universe is infinite, that's a bit too much for physicists to argue. I remember seeing a lower bound given inflation that the universe might possible be 10^30 times larger than the visible universe, but that's still as far from infinite as the number 1 is.

I'm also not against the inflation model, which is what I guess you're referring to when you're talking about 'solid physics'. Unless you're talking about the physics the inflation model is stuck into, General Relativity and Quantum Field Theory.

The discussion isn't about inflation cosmology which is pretty well attested, even without the latest data coming about polarisation of the cosmological background radiation, we already had several independent lines of evidence for it: lack of magnetic monopoles, flat spacetime, distribution of the microwave background. And a typical consequence of most inflation models is that there's a lot of little space time bubbles floating around.

The problem unfortunately is that its unlikely that this process could run infinitely into the past, at least not without introducing specially constructed spacetimes. This is not something cosmologists accept, its the accepted approach so far to assume that there won't appear to be anything special to the way the universe is arranged. Its a typical distribution.

[Carrikature]

Forgive me for jumping in without having read all the responses, but I had some questions. This is a somewhat new area of discussion to me, and I'm not terribly confident I've yet grasped the arguments, so bear with me.

If I have this right, the argument goes something like this:

1. If there is an infinite past there is enough time for all possibilities to be made actual.

2. It is possible for all matter or energy to not exist.

3. Therefore matter or energy should not presently exist.

The only problem I see is premise two - but then one would have to make the case that it is impossible for matter or energy not to exist. I don't see how one gets there. Thoughts?

Why wouldn't "all possibilities" include matter/energy ceasing to exist then beginning (later) to exist? How does one divorce infinite past from causality to establish P1 or, alternately, show that all possibilities can causally form in some (infinitely long) sequence? How is the existence of a finite past excluded from the set of "all possibilities"? How does this work in cases where time is a causal effect, or do those cases not exist?

[seer]

You're right, that's another heresy seer.

God is simple, he has no parts, he is identical to his substance. So its impossible for God to take a chunk of himself and fashion it into the world. At least not without ending up with pantheism, which Christianity denies to be the case. God isn't part of the world, he stands in relation to it.

So when God created the world, he created it out of nothing. He was all there was in the beginning, and then he made something that wasn't himself. There's no logical contradiction in asserting this.

Leonhard, I thought that from nothing, nothing comes(ex nihilo nihil fit)? Where would the material come from, if not generated from God's own being? And my position wouldn't be Pantheism but a form of Panentheism.

[seer]

Why wouldn't "all possibilities" include matter/energy ceasing to exist then beginning (later) to exist?

So you think it is possible for matter/energy to simplly pop into existence? From where?

How does one divorce infinite past from causality to establish P1 or, alternately, show that all possibilities can causally form in some (infinitely long) sequence? How is the existence of a finite past excluded from the set of "all possibilities"? How does this work in cases where time is a causal effect, or do those cases not exist?

I have no idea what you are saying. Try wording it so that even I can understand it...

[Carrikature]

It has to terminate at something which is pure actuality.

I think my ultimate complaint is not with the logic that leads to this conclusion but with the claimed nature of that pure actuality. I feel pretty confident that one could grant that the pure actuality exists as stated without ever being able to approach 'God' as the form of that actuality. It's the same thing with the KCA. I don't think the KCA works, but even if granted I don't think it accomplishes anything meaningful from an apologetics standpoint.

Mind, I put God in scare quotes for a reason. I grant that one could simply call pure actuality "God" if one chose, but I contend that the issue isn't the name of pure actuality but with the additional attributes it's supposed to have.

[Carrikature]

So you think it is possible for matter/energy to simplly pop into existence? From where?

In truth, I don't think we know what the essence of matter/energy is sufficiently to answer this question. However, that's only mildly relevant to what I was getting at. If you allow that matter/energy ceasing to exist is a possibility, on what grounds to you exclude its beginning to exist as a possibility?

I have no idea what you are saying. Try wording it so that even I can understand it...

I'll try. These are separate questions, though, so it may not be that simple...

For the first question, the short version is that I don't think you can exclude causality as a fundamental aspect of existence. If I'm right, then every state that comes into being must in some way be linked to the state that existed prior. If causality is not excluded, I suggest you would have to show the sequence of events that leads from one state to the next. I would further suggest that causality actually limits what states can or cannot exist. If you disagree that causality is a fundamental aspect, I think you need to explain how states begin or cease to exist. We're talking about an infinite past, after all, not a multiverse concept where all possibilities exist more or less simultaneously.

For the second question, how do you determine what does or does not get included in "all possibilities"?

The third question ties the two previous questions together. Time itself in our universe is at some level a result of the Big Bang (so far as I understand it). It doesn't make sense to ask what came before because 'before' is rooted in time. No time, no before. Infinite past loses all meaning if there is no 'past'. A good analogy might be a subroutine (don't know how much programming you know). The subroutine can run within a larger program. The subroutine can be entered and exited at specific points. So too with possible states. If one of those subroutines is 'time', anything within that subroutine could be considered to have a finite past. Does that make more sense?

[seer]

In truth, I don't think we know what the essence of matter/energy is sufficiently to answer this question. However, that's only mildly relevant to what I was getting at. If you allow that matter/energy ceasing to exist is a possibility, on what grounds to you exclude its beginning to exist as a possibility?

Well something going out of existence seems plausible to me, something popping into existence from nothing doesn't - does it to you?

I'll try. These are separate questions, though, so it may not be that simple...

For the first question, the short version is that I don't think you can exclude causality as a fundamental aspect of existence. If I'm right, then every state that comes into being must in some way be linked to the state that existed prior. If causality is not excluded, I suggest you would have to show the sequence of events that leads from one state to the next. I would further suggest that causality actually limits what states can or cannot exist. If you disagree that causality is a fundamental aspect, I think you need to explain how states begin or cease to exist. We're talking about an infinite past, after all, not a multiverse concept where all possibilities exist more or less simultaneously.

If you basically are saying that cause and effect is necessary or a fact, then I agree. But I'm not always sure what you are saying.

For the second question, how do you determine what does or does not get included in "all possibilities"?

Well that is why I said in my OP that I see premise two as a possible problem. Is it impossible for matter energy to cease existing - in principle I don't think it is.

The third question ties the two previous questions together. Time itself in our universe is at some level a result of the Big Bang (so far as I understand it). It doesn't make sense to ask what came before because 'before' is rooted in time. No time, no before. Infinite past loses all meaning if there is no 'past'.

I always looked at this argument as rather ambiguous Carrikature. Either matter and energy are infinite into the past or they are not. And if you had a physical cause and effect chain that led up to this universe then you would still have time, even before this present cosmos.

[Carrikature]

Rearranging slightly to answer similar questions. I don't think this messes up context too much (in this case).

Well something going out of existence seems plausible to me, something popping into existence from nothing doesn't - does it to you?

...

Well that is why I said in my OP that I see premise two as a possible problem. Is it impossible for matter energy to cease existing - in principle I don't think it is.

I would argue that something going out of existence isn't any more or less plausible than it popping into existence. That's part of the question, I guess: why one and not the other? The corollary to "where does it come from?" is "where does it go?", after all.

My viewpoint is that things neither begin nor cease to exist in the manner you mean. They merely...change form.

If you basically saying that cause and effect is necessary or a fact, then I agree. But I'm not always sure what you are saying.

I am saying that, yes. I happen to think there are plausibly some states of "all possibilities" that aren't actually possible within a single cause/effect chain. If I'm right, the first premise is false.

I always looked at this argument as rather ambiguous Carrikature. Either matter and energy are infinite into the past or they are not. And if you had a physical cause and effect chain that led up to this universe then you would still have time, even before this present cosmos.

In my view of changing forms as somewhat hinted at above, matter/energy/time are forms. A better explanation might use states of matter. H2O could be liquid, solid, or gas (keeping things simple for now). We call the liquid form 'water', the gas form 'water vapor', and the solid form 'ice'. (Obviously, you know that part.) If water is heated enough, it becomes water vapor. We could say that water ceased to exist and water vapor began to exist. H2O is still H2O, though. Using this analogy, I'm claiming that energy/matter/time are terms like water/ice/water vapor. You're using time as an H2O equivalent, and that is where the disconnect begins.

[seer]

I would argue that something going out of existence isn't any more or less plausible than it popping into existence. That's part of the question, I guess: why one and not the other? The corollary to "where does it come from?" is "where does it go?", after all.

My viewpoint is that things neither begin nor cease to exist in the manner you mean. They merely...change form.

I still think the idea of something going out of existence makes more sense than something coming into existence out of nothing.

I am saying that, yes. I happen to think there are plausibly some states of "all possibilities" that aren't actually possible within a single cause/effect chain. If I'm right, the first premise is false.

Why aren't they possible?

In my view of changing forms as somewhat hinted at above, matter/energy/time are forms. A better explanation might use states of matter. H2O could be liquid, solid, or gas (keeping things simple for now). We call the liquid form 'water', the gas form 'water vapor', and the solid form 'ice'. (Obviously, you know that part.) If water is heated enough, it becomes water vapor. We could say that water ceased to exist and water vapor began to exist. H2O is still H2O, though. Using this analogy, I'm claiming that energy/matter/time are terms like water/ice/water vapor. You're using time as an H2O equivalent, and that is where the disconnect begins.

I don't see it. If you have a physical cause and effect chain existing before this universe then you would still have time. Why wouldn't there be?

[Carrikature]

I still think the idea of something going out of existence makes more sense than something coming into existence out of nothing.

I know I come across pretty bluntly both because of how I post and the nature of the internet, so please understand that this is not meant to sound harsh. "I think that X makes more sense" is pretty useless other than as a statement of position. Yes, you think that. So what? Why should I think that? Why should anyone think that? Why do you think that? Answering any of these questions would be a better response than "I still think", in this case.

Why aren't they possible?

There are a lot of reasons. Positing an infinite chain doesn't exclude infinite loops, for one. Use the causal chain: X -> Y -> Z -> B -> R -> X. If S, M, and P are all possible states, they still never occur in this chain. Just because a state is possible doesn't mean it's ever actualized. It's a question of what effects, if any, are necessary results of a given cause. It's possible that some potentials never get actualized.

I don't see it. If you have a physical cause and effect chain existing before this universe then you would still have time. Why wouldn't there be?

Because time is itself an effect. For it to always exist, it would have to be outside the causal chain.

[seer]

I know I come across pretty bluntly both because of how I post and the nature of the internet, so please understand that this is not meant to sound harsh. "I think that X makes more sense" is pretty useless other than as a statement of position. Yes, you think that. So what? Why should I think that? Why should anyone think that? Why do you think that? Answering any of these questions would be a better response than "I still think", in this case.

Yes, but you said:I would argue that something going out of existence isn't any more or less plausible than it popping into existence.

Isn't your statement just as useless?

There are a lot of reasons. Positing an infinite chain doesn't exclude infinite loops, for one. Use the causal chain: X -> Y -> Z -> B -> R -> X. If S, M, and P are all possible states, they still never occur in this chain. Just because a state is possible doesn't mean it's ever actualized. It's a question of what effects, if any, are necessary results of a given cause. It's possible that some potentials never get actualized.

But then why would we conclude that these other states were really possible at all? How is that knowable?

Because time is itself an effect. For it to always exist, it would have to be outside the causal chain.

So is time "outside" of the present universe? Isn't this cosmos just one effect in the chain?

[shunyadragon]

What on earth does that mean?

What ever Infinite regression you propose, there will always be something beyond it

[seer]

What ever Infinite regression you propose, there will always be something beyond it

Like what?

[Carrikature]

Yes, but you said:I would argue that something going out of existence isn't any more or less plausible than it popping into existence.

Isn't your statement just as useless?

Not really, but I can see the confusion. My statement was an answer to your question. My criticism isn't about stating the position but about repeating the position in the face of questioning ("I still think that"). Yes, I made a statement of position. So did you. Both of those are useful things. I asked you to show what the difference is, and I tried to illustrate (even if unsuccessfully) why it's not simply obvious that the difference exists. Your response was to reiterate the position. The reiteration is what's useless.

But then why would we conclude that these other states were really possible at all? How is that knowable?

It may not be knowable, and probably isn't. The better question is what metric is being used to determine what is or isn't possible. That's what I was asking in the first place. You've suggested that matter ceasing to exist is possible. How do you determine that? Why is "matter ceasing to exist" possible while "matter beginning to exist" is not? What metric are you using?

ETA:
We could conclude that these other states are possible because they present no logical impossibilities, if that makes sense.

So is time "outside" of the present universe? Isn't this cosmos just one effect in the chain?

Time is not outside of the present universe as best I understand it. I don't know if I think this cosmos is just one effect in the chain. If it is, it would be plausible that there are separate conceptions of time. Time1, in relation to the present universe, is finite. Time2, in relation to the entire cosmic causal chain, is infinite. You could even have an infinite number of finite timelines.

[seer]

Not really, but I can see the confusion. My statement was an answer to your question. My criticism isn't about stating the position but about repeating the position in the face of questioning ("I still think that"). Yes, I made a statement of position. So did you. Both of those are useful things. I asked you to show what the difference is, and I tried to illustrate (even if unsuccessfully) why it's not simply obvious that the difference exists. Your response was to reiterate the position. The reiteration is what's useless.

Ok, fine, but we are both in the realm of opinion. I gave my opinion, you gave yours. What else is there at this point?

It may not be knowable, and probably isn't. The better question is what metric is being used to determine what is or isn't possible. That's what I was asking in the first place. You've suggested that matter ceasing to exist is possible. How do you determine that? Why is "matter ceasing to exist" possible while "matter beginning to exist" is not? What metric are you using?

I, like you, am using intuition. I can imagine something going out of existence, I can't imagine something coming from nothing. Can you?

ETA:
We could conclude that these other states are possible because they present no logical impossibilities, if that makes sense.

I guess if you think it is possible for something to pop into existence out of nothing then nothing would be logically impossible in your mind. So we are back to dueling opinions...

Time is not outside of the present universe as best I understand it. I don't know if I think this cosmos is just one effect in the chain. If it is, it would be plausible that there are separate conceptions of time. Time1, in relation to the present universe, is finite. Time2, in relation to the entire cosmic causal chain, is infinite. You could even have an infinite number of finite timelines.

I think as long as you have physical cause and effect you have time. It is after all successive events are what marks time. In this case there would be no break in the chain, one event leads to another, finally to this present universe.