The Universe Itself Keeps On Expanding, And Expanding…

Question from Andreas:
I know, this may have already been answered, but this piece of information so far successfully hid from my search for knowledge. This is why I’d like to ask a physicist
— Lawrence Krauss — these two questions regarding space and time.

Question 1:
First, as I get it, since Einstein there is no universal time, but a space-time. (Newton was so much easier to grasp for a simple human mind.) Means, space and time are tied together, influence each other and got into existence at the same time which was the big bang. Am I right so far?
Thus space started to exist and to expand since then, as did time — start to exist, that is.

So here comes my first question, because I don’t understand a “what was before” question I sometimes read or am asked (mostly by religious people). I don’t claim to understand Einstein, and I assume only a dozen people on Earth fully do — so maybe I got it all wrong, which is why I have to get this answered.
Is it true that there was no time before the big bang? If so, why are people asking themselves, how and when and why the big bang took place? It cannot be answered (well, the how can be answered to an extent) when there was no time in existence before, so there was no “before the big bang”… or what did I get wrong here?
And the implications? Am I right about shaking my head if people ask the “but what was before” question?!?

Question 2:
Another issue I have with time is distance, the speed of light and our view into the universe. Due to the limitation of the speed of light, we look backwards in time when we look into the universe and see distant galaxies. So we see the past. The farther away a star/galaxy is, the older the image we see. So how do we know if it’s still there? How do we know if a galaxy very far out, in a distant past, isn’t long gone and its stars exploded in nova and supernova explosions? And how far can we look back? I once read that the farthest out we can see is the actual time of the plasma that was “shortly” after the big bang… and we cannot see past that. And that we can see residual “background noise.” If that is true, how can we have a current picture of the universe? Isn’t everything we think about it an extrapolation of a past situation—the only thing that we can see, but we have to calculate how it might have developed since then to now in order to have a full understanding of the universe in its present state?

Isn’t it therefore impossible to have a clear picture of the universe, its number of galaxies, its size etc.? It could be no more than a wild guess, like “yes, we see the images, but we cannot put it together in one map of the current (state of the) universe…”

Those were my two questions.
I am really looking forward to seeing them answered by someone who actually understands what he’s saying, and can even do the calculations (e.g. the time+distance thing), as this gives me headaches for a year or two now, and I just couldn’t find it anywhere else… yet.

The biggest thanks in advance!

Answer by SmartLX:
With the disclaimer that I am absolutely not Lawrence Krauss, I’m happy to help.

Question 1:
There are multiple cosmological models with some kind of Big Bang, and there is a form of time “before” it in some of them. When considering the multiverse hypothesis in particular, you have to consider the possibility that before our system of space-time began others might already have been running. (“Before” in this context relates to causality; if something in another system of space-time caused ours to emerge, you can think of the cause coming before the effect.) If indeed there was no time before the Big Bang, though, then the “before” question is indeed inapplicable, and our ideas of cause and effect have a hard time applying as well.

To summarise in the context of the religiously-charged “what was before” question, we don’t know whether there was a before, if there was a before there didn’t have to be a god in it, and if there wasn’t a before then the Cosmological Argument is nonsensical. The Argument from Contingency is a version that attempts to get around the time-based limitations, but it still has most of the same flaws.

Question 2:
Statistically speaking, we know many stars we can see are long “dead”. Our sun has a total lifespan of about ten billion years, and the larger a star is the sooner it burns out. The best telescopes can pick up images from several billion light years away, and some of the far-out stars are hundreds or thousands of times bigger than the Sun. Even one billion light years out, time will be up for a significant percentage of them since they’ve had to last another billion years since they radiated the light we’re seeing.

So of course our picture of the universe is incomplete. We live in a fortunate time, cosmologically speaking, because the expansion of the universe hasn’t progressed to the point where all galaxies are out of sight of each other, or else we might not know there are other galaxies at all. As it is, we are constantly revising our estimates (and estimates they certainly are) about the contents of the universe based on the information we can gather. Right now the estimate for the proportion of stars with planets around them is rocketing upward as we find evidence of more and more extra-solar planets. Just because we don’t know everything doesn’t mean we can’t learn anything.

I think you misunderstand one significant thing. Our model of the present universe is not an extrapolation from an assumption of the Big Bang; rather our concept of the Big Bang itself is largely an extrapolation from the current state and movement of the universe. Put simply, everything is rushing away from everything else (unless held together by local gravity) so in the past everything was closer, further in the past everything was even closer than that…and at some point beforehand everything was together, and the physicists worked from there. We try to model the current universe based as much as possible on real observations of its present state, rather than extrapolating from an extrapolation – though sometimes we do resort to that.

Feel free to pick up on any of these points in a comment if you think it could be clearer.

Might Be Talking To The Wrong Guy

Question from Jesse:
Where did the gravity come from Mr Hawkins? I’m just curious.

Answer by SmartLX:
I’m going to assume this is a question to Stephen Hawking by proxy. It’s the right question as it turns out, as Hawking’s position in A Brief History of Time is that gravity essentially caused the universe. As for its own origin, notwithstanding the limitations of language when describing different workings of time, it was always there, just as you might assume God always was.

If you have a problem with this I suggest you read A Brief History of Time, check any articles which might indicate that Hawking has changed his position since 1988, and address any further correspondence to him.

The Beginning Ain’t the Be-All and End-All

Question from John:
Universe had a beginning, “proved” by second law of thermodynamics.
Dear Sir, I understand that an argument used by creationists, in favour of a Universe that had a beginning, is that the second law of thermodynamics requires that it will inevitably wind down. In essence, the claim is that the universe can not have been infinite into the past as it would have inevitably already run down. The fact of a purported finite amount of usable energy therefore implies that the universe MUST have had a beginning or else we would not be here now to discuss this. Is there a scientific rebuttal to this claim please?

Answer by SmartLX:
There are two principal possibilities which address the idea of an infinite universe having run down by now, both of which are centered around the concept of renewal.

1. The universe periodically contracts in a Big Crunch before a new Big Bang. This drags together not only all the matter in the universe but all the space and time as well. All the unusable energy lost to the edges of the universe is brought back to the singularity and can be useful once again.
2. The matter and energy in the hypothetical (but currently quite likely-looking) multiverse is infinite. When one universe runs down, countless others are still going and more universes spontaneously start up all the time. No laws of physics are broken by this sudden emergence if the amount of anti-matter that emerges is equal to the amount of matter, because matter and energy are conserved in an equation akin to 0 = 1 + -1.

Creationists often think, as they are told to by people like William Lane Craig, that once they establish that the universe had a beginning the argument is basically sewn up. Even if the above two possibilities are dismissed and you take it as read that the universe began, that it was begun by a god can only ever be an argument from ignorance. Without knowing how it happened, you can’t just assert it was one particular thing without eliminating all other possibilities, even the ones people haven’t thought of yet. The potential for spontaneous emergence from the “quantum foam” suggested by quantum mechanics, for one, ensures for the moment that well-formulated alternatives are out there, and you don’t even have to appeal to the un-thought-of.

The Pretend Prime Mover

Question from Sue:
Since God is pretend, how did the world come to be?

Answer by SmartLX:
We don’t know, but there are lots of ideas floating around. We’ve covered it quite a lot here, so try a search or just use this one. Just because the idea of a God explains something doesn’t make it any more likely that there is one.

The Universe and Everything

Question from Bryson:
So based on scientific evidence the universe at one time began to exist right? Explained by What we call the big bang theory. Another law is whatever begins to exist has a cause right? As in there’s something that begins to exist, there’s a cause for it, it existing being the effect. So if a universe existed, logically there’s a cause. Since the universe hasn’t existed yet, there’s no time/space/energy. Which leads to the conclusion that the cause of this “big bang” has to be something outside the laws of time/space/matter.

Well since only two things fall under this category, one would be a divine entity, the other an abstract object like the number 1 or something. My question is how would something abstract be a cause? I know Stephen Hawking said something along the lines of because of the laws of the gravity, there is no need for a creator because that proves the universe will create itself from nothing. But, of course, after thinking about it, if the universe hasn’t existed yet, that would mean the laws don’t exist yet. Plus, while the laws of gravity are describe gravity, it has no creative power. If put 1 dollar in the bank, and then next week 2 dollars, I can logically and mathematically explain why I now have $3. But, if I put 1 dollar in the bank and depend on mathematics to increase it, I would never have more than $1.

I know some people have even talked about something to do with a multiverse, but of course that doesn’t disprove god either because logically with a being capable of creating one universe, why would he not be able to create more if it wished.

Answer by SmartLX:
The good old cosmological argument. This argument falls at the first hurdle, but drags on and knocks over all the others regardless.

– No, scientific evidence has not established that the universe began to exist. It has established that it was once concentrated at or near a single point, then expanded outwards. The evidence says nothing about whether the matter and energy in that point was created at that instant or it got there from somewhere else.

– There are two modern perspectives on matter and energy. According to the classical laws of conservation, they may be converted into each other but they are never created or destroyed. Since they exist now, this would imply that they have always existed and didn’t need a creator. On the other hand, according to quantum mechanics matter can emerge spontaneously in certain circumstances as long as the same amount of antimatter does too, because the total amount of positive energy stays the same. Again no creator is needed, so neither way supports the supposed necessity of a creator.

– If the Big Bang was caused by something outside of our universe’s space and time, it doesn’t make the cause timeless or spaceless. It might be a natural entity with its own spacetime and energy, say, another universe.

– We have never unambiguously observed a divine entity, so it is pure assertion to say it can exist outside of space and time. We have only observed the “abstract” (mathematics, logic, etc.) within the confines of a physical universe as it affects the objects in that universe, so we don’t know whether the abstract can exist without the material either. Regardless, you pose a false dilemma because there is at least a third choice: an object in a different system of spacetime. And the whole thing is moot until the necessity of a cause is established.

– No, the possibility of a multiverse doesn’t disprove the existence of a god, but nothing does. A god is a possibility in a multiverse as well as in a single universe. There’s just no good reason to think it’s real, let alone necessary.

Deism by way of Michio Kaku

Question from “Alex the Deist”:
This last month, there has been some news about the existence of God proved by Michio Kaku, who asserts that the universe is perfectly ordered, “it could have been chaotic”, but it is not. He says that with this we could understand the mind of God. The ultimate argument for design.

Now, I know that Kaku is agnostic or pantheistic like Einstein, and that this is poetry, but nonetheless, it has theological implications. The first is that this would practically rule out the existence of personal gods, but this I think, makes deism stronger than atheism.

Consider the following case:

The universe is ordered / design.
The universe is ordered / blind chance.

We should expect that if there is a design behind the universe, this would be ordered. But we could not expect the same of blind chance. So, order gives a higher plausibility to design than to chance.
_____

On the other hand for example, Dennett says that we as rational beings find useful to think of things as involving a purpose, this makes easier to understand natural phenomena. Which is true, I accept that. But I think, that if we accept that; we should accept it is possible that a mind responsible for the universe exists, and that our understanding expresses cognition about it.

If we accept that this order is objective and not an invention of our minds (as I think every rational person would accept) we should be able to tell that such order expresses also some kind of objective rationality, that it is true that: we as rational beings can comprehend such order because/and it expresses rationality.
_____

This two things being said, I think deism has an extremely greater plausibility than atheism. How do you respond to this from an atheistic frame?

Answer by SmartLX:
It’s not really news that the universe appears to be entirely ordered in some sense. The laws of physics and the fundamental constants have so far seemed universal and unchanging, with nothing behaving contrary to them. It can be said, and I agree that no one would seriously argue, that there is at least some order in the universe, which leads into the rest of your argument. Thing is, people have been arguing that the existence of order demonstrates design and therefore a god for centuries, so it hasn’t been the most successful of arguments and Kaku is unlikely to change that.

You avoid affirming the consequent (a common fallacy) by restricting yourself to a probabilistic claim that design is more likely than chance, but nevertheless there is no way to establish the absolute or relative probability of either your hypothesis or the opposite. Minds are constantly observed to create local order, yes, but so are chance and undirected determinism. Rocks are worn smooth, sunflowers and pineapples follow Fibonacci patterns, a roughly shaken container will sort its contents according to size and density. A mind is not automatically more likely to have created universal order just because the majority of order we notice is the product of minds.

With the two sides now on murky but level ground, a major difference between your hypothesis and non-deistic alternatives is that you are required to posit the prior (or timeless) existence of another extremely ordered entity for which there is no available, substantial evidence, whereas natural explanations leave open the nature of the progenitor, if any. I wouldn’t dispute that a creator god is possible as we have no means to rule it out (an agnostic atheist leaves room for any possibility), but that’s as far as it’ll go. It’s perilous to argue that one possible explanation is more likely or “stronger” because of what we “should expect” when it comes to the whole universe, because our intuition is woefully inadequate for this purpose.

The World of Leftover Energy

Question from Andrew:
Why do atheists like Stenger say that the universe can be eternal, when this does not hold?

Stenger argues that the universe can be eternal, non-created, extrapolating the law of conservation of energy-mass before the planck time, he says that because we do not see a violation to this law, the universe can perfectly be eternal.

But this is a fallacy as William Lane Craig exposed once. If the energy were eternal there would be no useful energy right now, it would have become useless, complete entropy an infinite time ago, and because we do not see this, the only conclusion is that the universe and the energy began a finite time ago. Where we Christians think, the best explanation is the creation by God.

Answer by SmartLX:
Even according to you, Stenger only said the universe can be eternal, not that it definitely is. If it isn’t, then God is only one possibility among who knows how many: spontaneous emergence (more on that in a sec), a previous universe, a deistic rather than theistic (let alone Christian) god and so on.

Anyway, there are at least three straightforward ways in which there can still be useful energy now after an eternity of existence. There might be others, but even one possible way is enough to keep someone like Craig from ruling out the possibility entirely.

1. There is infinite or potentially infinite energy as well as infinite time.
Our universe as we see it has existed for a finite amount of time since the Big Bang with a certain amount of matter and energy, but what if that only contained one portion of the available material of an endless universe or multiverse? Or can matter emerge regularly and spontaneously from the quantum foam as much as it likes, as long as the same amount of antimatter accompanies it and the total amount of “positive” energy stays constant? As Lawrence Krauss says, something can come from nothing if “nothing” is unstable.

2. The energy is periodically reclaimed.
Entropy doesn’t destroy energy (hence Stenger’s point), it only ends up radiating it towards the edges of the universe where it’s no use to anyone. If Big Bangs are regular rather than one-off occurrences, then there’s a long-standing hypothesis that the universe is first drawn together in a Big Crunch. The new singularity contains not only all the matter and energy of the crushed universe, but all the space as well. Whatever was lost to entropy is dragged back to a mathematical point, just like at the point of our own Big Bang, and the cycle can begin again.

3. The amount of available energy decreases exponentially.
The less energy there is, the slower it dissipates, the way a gush becomes a trickle when you tip out a bucket of water. Say that every billion years, the amount of available energy decreases by half. If so then a billion years ago there was twice as much, and two billion years from now there’ll be a quarter as much, but there will never, ever be none. It will approach zero (or, importantly, a non-zero constant) asymptotically, which is to say it will get closer and closer without ever reaching it. Perhaps the amount of energy we’re used to seeing in the world is practically nothing compared to the intense heat, light and motion that was everywhere in times gone by, with the universe in a state of near-saturation (perhaps asymptotically again). Without past reference points from before the Big Bang, which are probably impossible to attain, you can’t make a judgement that there can’t be this much energy now.

One final point: be very careful about expressions like “the best explanation” when discussing cosmology. If quantum mechanics have taught us anything, it’s that reality can be counter-intuitive, and the truth might well strike one as ridiculous. If there’s evidence for a claim then it’s a supportable claim, but if all it does is sound right then it’s worthless.

Universe(tm) – No God Required

Question from Jhon Roy:
How did the universe existed if there was/is no God to create it, do you want us Christians to believe that out of nothing, the universe began to exist??? It is indeed illogical. Steven Hawking said that because of gravity the universe can create itself, but as I told you before the universe began to exist, there was just nothing, no gravity, nor force. Now answer my question.

Answer by SmartLX:
Non-believers aren’t asking Christians to believe anything about this topic. There are many different ways our present universe might exist, and atheists don’t arbitrarily declare without evidence that a particular one of them is fact. We wait for scientists to uncover evidence favouring one hypothesis over all others, because they’re the only ones finding any relevant evidence at all. All I would ask is that because many of the possibilities do not involve a god, you accept for now that as far as we know the universe isn’t necessarily impossible without a god, and therefore its mere existence isn’t currently proof of a god all by itself.

Regarding the specifics of your argument:

  • How do you know there was nothing before the universe began to exist? You think God existed before the universe did, so why couldn’t something else? Another universe, for example?
  • How do you know the universe even began to exist, and didn’t always exist in some form? You think God always existed; it’s even simpler if the universe always did instead, because then we don’t have to try to explain the existence of a god as well as the universe.
  • Anything creating itself is by definition impossible because it implies an action by an entity which does not exist during the action, but Stephen Hawking’s ideas about the beginning of the universe involve the simultaneous emergence of time, making the concept of “before” irrelevant. Why can’t it have happened the way he describes, other than that it sounds wrong to you? Why can’t the universe behave in an un-intuitive manner, given how limited our intuition is? If it’s so obviously unworkable, why hasn’t a super-brain like Hawking or any of his colleagues realised it and hastily re-worked large sections of A Brief History of Time?
  • Incidentally, the simple fact that you’ve asked a question is reason enough for us to answer it. You don’t then have to order us to answer it.

    Eternal inflation? No. Eternal universe? Maybe, nevertheless. And what’s it to ya?

    “These three scientists in particular, by virtue of their joint paper, are name-checked more often than any others by apologists not just arguing for an absolute beginning to the universe but claiming that this has been established beyond doubt.”

    Question:
    Scientists Arvin Borde, Alan Guth and Alexander Vilenkin, in their 2003 paper “Inflationary Spacetimes Are Incomplete in Past Directions”, ruled out past-eternal inflationary models of the universe. Does this prove that
    1. the universe had an absolute beginning,
    2. that it must have had a cause and
    3. that the cause was God?

    Answer:
    No, no and no.

    These three scientists in particular, by virtue of their joint paper, are name-checked more often than any others by apologists not just arguing for an absolute beginning to the universe but claiming that this has been established beyond doubt. Apologists up to and including William Lane Craig do this to support the cosmological argument for God, which requires such a beginning to be indisputable.

    So what does the paper actually say? Feel free to read it via the link above (it’s dense but short), but the thrust is in the title: spacetime can’t have been inflating infinitely into the past.

    That seems obvious since you’d think you’d eventually reach a singularity if you worked backwards, but models have been proposed wherein the farther back you go the slower the expansion is. Some reasoned that perhaps the universe has spent eternity inflating extremely slowly from a size barely larger than a singularity, speeding up as it went along.

    Borde, Guth and Vilenkin examined this idea and found, essentially, that it wouldn’t work in the real world. In doing so they pretty much dismissed every model of an expanding universe (or multiverse) that doesn’t involve a proper singularity and Big Bang. Therefore, according to apologists, the universe definitely had an absolute beginning, which must have had a cause, and that cause was God.

    That’s going way too far because, for a start, the paper doesn’t take a position on whether the now-confirmed Big Bang was an absolute beginning. There are many more universe/multiverse models wherein the Big Bang was merely an event in an ongoing sequence – where the matter in the singularity came from somewhere, not nowhere. Borde et al only intended to rule out a family of models that clearly don’t work.

    Get that? Borde, Guth and Vilenkin did NOT rule out an eternal universe, even if the result of their paper is correct. They merely ruled out one kind of eternal universe, the kind where the Big Bang never happened. The fact that there was a Big Bang does not mean there was nothing before the Big Bang.

    The Big Bang as absolute zero, or an absolute beginning in general, is a poor platform for apologetics in any case. The idea that whatever begins to exist has a cause is not based on anything which physically began to exist in the same way the universe supposedly did, completely ex nihilo (literally “from nothing”). We’ve never seen anything like that happen, so:
    1. it’s curious that so many people assume the universe came about in this way,
    2. there’s no basis for assigning a cause if it did and
    3. even if it had a cause, it’s a huge leap to declare it any kind of god, let alone someone’s specific personal deity.

    SmartLX