This is a noob question:

In debates with Christian apologists they often claim it is impossible for a universe to come from "nothing" without a creator. However can it be said that there was ever "nothing" ? When the universe started to exist time came into being with it, so there was never a point in time when there was nothing. For every instant where time = X the universe has existed. There is no "before" state when there was nothing, so in a way the universe has always existed, if you assume always means every instant in time.

Thanks for those answers, though I am not sure it really answers my questions!

I guess the term "a universe from nothing" is something I remembered from Krauss.

I'm reminded of what Michio Kaku said on the subject, namely that when physicists talk about "nothing" in this context, what they actually mean, quite precisely, is an absence of matter particles. They do not for one moment regard other entities as not being present, such as a space-time metric or quantum fields. Furthermore, since it has been demonstrated empirically that particle-antiparticle pairs can appear transiently from vacuum energy fluctuations (Casimir experiment etc), and more persistent particles appear in particle accelerators whenever sufficient energy is supplied to the system (E=mc2 and all that), most modern cosmological scenarios involve energy conversions within systems of interest. Last time I checked, cosmologists all regard energy in some form as being present, even in a purportedly particle-free vacuum (assuming you can actually have one of these of course), and conversion of that energy into matter, in the same manner as occurs in particle accelerators, is regarded as a primary mechanism for the instantiation of persistent matter.

Arjan Dirkse wrote:When the universe started to exist time came into being with it, so there was never a point in time when there was nothing. For every instant where time = X the universe has existed. There is no "before" state when there was nothing, so in a way the universe has always existed, if you assume always means every instant in time.

Yep, this mirrors my own view quite well. If the universe has a finite age then that implies there was a first moment of time. But there can't be said to be a "before" the first moment of time. As such, the "state of the world" was never such that there was nothing (defined as an absense of all properties).

That means the universe must have always existed, but that doesn't entail the universe is infinitely old, or that the dimension of time stretches infinitely and endlessly far into the past. Since there was never a transition from "nothingness" (the absense of all properties) to "somethingness", there is no need for a cause to actualize such a transition. The universe simply is and it always was.

You can ask why it is so, why does the universe exist? And my answer is "why do you think there is a why and what answer could be given even in principle that does not immediately raise a similar one?".

Rumraket wrote:

Arjan Dirkse wrote:When the universe started to exist time came into being with it, so there was never a point in time when there was nothing. For every instant where time = X the universe has existed. There is no "before" state when there was nothing, so in a way the universe has always existed, if you assume always means every instant in time.

Yep, this mirrors my own view quite well. If the universe has a finite age then that implies there was a first moment of time. But there can't be said to be a "before" the first moment of time. As such, the "state of the world" was never such that there was nothing (defined as an absense of all properties).

That means the universe must have always existed, but that doesn't entail the universe is infinitely old, or that the dimension of time stretches infinitely and endlessly far into the past. Since there was never a transition from "nothingness" (the absense of all properties) to "somethingness", there is no need for a cause to actualize such a transition. The universe simply is and it always was.

You can ask why it is so, why does the universe exist? And my answer is "why do you think there is a why and what answer could be given even in principle that does not immediately raise a similar one?".

Similar to my own (admittedly layman's) view. To imagine a "before the universe" is a thought experiment, taking a property of the universe, namely time, and placing it outside the universe. A proponent of this thought experiment would have to explain and justify this first step before being in a position to develop the argument any further.

Thanks for all the answers...they're as good an an answer as can be given.

The crux of my question is probably why the religious peddlers in these debates get away with claiming there must have been a point when nothing existed which transitioned into something existing. It seems a silly argument.

Actually, it's more of a strawman than a claim - they claim atheists (Or cosmologists) must think there was 'nothing' before the big bang. What they claim is there must have been a something before the creation of the universe; a creator.

Put simply: nothing is something.

BlackBart wrote:Actually, it's more of a strawman than a claim - they claim atheists (Or cosmologists) must think there was 'nothing' before the big bang. What they claim is there must have been a something before the creation of the universe; a creator.

Which of course brings the question of when and where did the creator come to be, so postulating a creator of the cosmos and time is no help answering a before question either. Then they'll say the creator exists outside of space and time and has always existed, and I'll say ok. No different of a claim than the cosmos always having existed, in my opinion.

The_Piper wrote:

BlackBart wrote:Actually, it's more of a strawman than a claim - they claim atheists (Or cosmologists) must think there was 'nothing' before the big bang. What they claim is there must have been a something before the creation of the universe; a creator.

Which of course brings the question of when and where did the creator come to be, so postulating a creator of the cosmos and time is no help answering a before question either. Then they'll say the creator exists outside of space and time and has always existed, and I'll say ok. No different of a claim than the cosmos always having existed, in my opinion.

Yup. The God thingy doesn't bring anything useful to the party.

BlackBart wrote:Actually, it's more of a strawman than a claim - they claim atheists (Or cosmologists) must think there was 'nothing' before the big bang. What they claim is there must have been a something before the creation of the universe; a creator.

Which is another of those blatant and deliberate misrepresentations that supernaturalists think they should be allowed to get away with, and whinge if they're called out thereupon.

Arjan Dirkse wrote:

In debates with Christian apologists they often claim it is impossible for a universe to come from "nothing" without a creator.

I would stop them right there and ask: "How do you know that it is impossible for a universe to come from nothing without a creator?"

If they start with the "all things that move must have a mover" nonsense, I would ask: "How do you know that the universe must follow laws that govern things within the universe?"

I just say 'uh hunh" and go back to my beer.

Shagz wrote:

Arjan Dirkse wrote:

In debates with Christian apologists they often claim it is impossible for a universe to come from "nothing" without a creator.

I would stop them right there and ask: "How do you know that it is impossible for a universe to come from nothing without a creator?"

If they start with the "all things that move must have a mover" nonsense, I would ask: "How do you know that the universe must follow laws that govern things within the universe?"

One problem being of course, that the whole business of regarding testable natural processes as responsible for the instantiation of the universe, which physicists all subscribe to, is based partly upon the precedent that testable natural processes have been robustly and repeatedly demonstrated to be sufficient to account for vast classes of observable entities and phenomena. As a corollary, physicists see no reason for that precedent to be broken. What those physicists anticipate, when you actually bother to ask them, is that new physics will be alighted upon governing the universe instantiation process, though of course that physics has to be consilient with what has been discovered before.

This course of inquiry, however, is routinely and egregiously abused by pedlars of apologetics on behalf of low-grade mythology. Said abuse consisting of ignoring the pursuit of possible new physics, and erecting a dishonest requirement that only what is known currently should be applicable, regardless of whether any new physics is just around the corner waiting to be announced, that solves the problem neatly. The fabrication of this duplicitous constraint is then roundly abused still further, to try and suggest that the past success of testable natural processes will somehow magically fail in this instance, and that the only resolution is to treat their mythology's assertions on the matter as true by default. Hoping, of course, that the uneducated will not notice that the business of seeking out testable natural processes has [1] been spectacularly successful, and [2] has alighted upon entities and phenomena that the authors of those low-grade mythologies were incapable of even fantasising about.

Plus, even if we don't have new physics waiting around the corner, the assertion that the physics we do have knowledge of, is purportedly so constrained as to make universe instantiation impossible via testable natural means, is itself an assertion demanding deep critical examination. Since pedlars of apologetics have been spectacularly wrong on the matter in so many other cases, there's no reason to suggest they're anything other than wrong here too. We already know that it's possible to synthesise particles in particle accelerators that didn't knowingly exist before, and that the spontaneous appearance of particles in the right circumstances is an observed fact (Casimir experiment et al), so the idea that a universe enjoys a special status in this regard is merely another unsupported (and probably false) assertion, because at bottom, a universe is a region of spacetime populated with lots of particles. If all it takes is a mechanism for the dumping of lots of energy into that spacetime to fill that spacetime with the requisite lots of particles, then it's game over, and indeed, finding such a mechanism is a pretty central focus of much modern cosmological research.

Calilasseia wrote:

Shagz wrote:

Arjan Dirkse wrote:

In debates with Christian apologists they often claim it is impossible for a universe to come from "nothing" without a creator.

I would stop them right there and ask: "How do you know that it is impossible for a universe to come from nothing without a creator?"

If they start with the "all things that move must have a mover" nonsense, I would ask: "How do you know that the universe must follow laws that govern things within the universe?"

One problem being of course, that the whole business of regarding testable natural processes as responsible for the instantiation of the universe, which physicists all subscribe to, is based partly upon the precedent that testable natural processes have been robustly and repeatedly demonstrated to be sufficient to account for vast classes of observable entities and phenomena. As a corollary, physicists see no reason for that precedent to be broken. What those physicists anticipate, when you actually bother to ask them, is that new physics will be alighted upon governing the universe instantiation process, though of course that physics has to be consilient with what has been discovered before.

You say that vast classes of observable phenomena have been robustly demonstrated, which I'm sure is true, but there are still phenomena that are not understood. Dark matter comes to mind, unless that has changed recently. And while it's true that there is a precedent for testable processes explaining phenomena within the universe, I doubt that anyone is absolutely certain that these precedents can be applied to determining the origin of the universe itself. I suggest that anyone who knows with certainty, using our current understanding of physics, that the universe itself must follow laws that govern things within the universe is either kidding themselves or deserves a Nobel prize in physics. Though I'm no expert, and will gladly bow to anyone more knowledgeable than I am if they say I am full of shit.

Now, is it reasonable to say that the universe itself most likely must follow laws that apply to everything within itself? I don't know, but if you say most physicists will say that it is, I'll take your word for it. Let's say that it is reasonable to say that, and, for the sake of argument, let's say that science becomes as certain as is possible that the universe had an absolute beginning. Would it then be reasonable to say that that absolute beginning had some kind of cause? I'm not so sure. I'm not even sure that anyone knows for sure that everything within the universe always must have some kind of cause. Physicists surely can make a better educated guess than I can, but I still would wonder if they could know for sure. One thing that is certain is that the average theist trying to use the "all things that move must have a mover" argument is not going to know for sure.

Calilasseia wrote:... at bottom, a universe is a region of spacetime populated with lots of particles. If all it takes is a mechanism for the dumping of lots of energy into that spacetime to fill that spacetime with the requisite lots of particles, then it's game over, and indeed, finding such a mechanism is a pretty central focus of much modern cosmological research.

Cali, that idea is not consistent with the accepted view that our space-time was actually created in our big bang, rather than play host to it (having, presumably already existed), because it requires that there was an abundance of empty space before it, with just a minute, super dense blob, waiting to suddenly and inexplicably start expanding. I long ago described a more self-consistent picture, based on the work of the cosmologist/mathematician, Lee Smolin, who, among other things, proposed a version of loop quantum gravity that allows for a large enough black hole to generate a space-time of its own. He later back-tracked on it (on the dubious grounds that it couldn't explain the masses of neutron stars in this universe), although I suspect that the real reason was that he didn't want to be seen as a "multiverse crank".