How could our universe suddenly appear out of nothingness? I understand that the big bang created all things but how could it when nothingness is purely the absence of everything?
Look at what Peter van Inwagen says in his book "metaphysics" (an excellent read) on this issue. He accuses physicists who claim to have solved the philosophical problem of origin or creation of conflating the notion of "philosophical nothingness" with "physical nothingness". The problem with many answers from physics, as @infatuated pointed out, is they don't assume complete nothingness. For a singularity to expand, there must be time. Nothingness + time does not equal nothingness.
This is a difficult question in metaphysics which dates back quite far, possibly to the time of Parmenides who raised the issue of making "negative existential statements". As far as answers go, if one could prove, for example using the modal ontological proof, that a necessary being necessarily exists, we answer the question. This brings us to one possible way of answering the question: proving that nothingness is a reality which is impossible to obtain. Both the Ontological and the Cosmological arguments seek to do this (if you're not familiar with them, they're good things to know). Consequently, if one could prove that something necessarily exists, we could also answer the question. I believe some philosophers, including van Inwagen attempt to prove this by comparing the probabilities of nothingness vs. something, given the available evidence, to show that it is highly improbable, almost impossible, for nothing to have existed - although this still doesn't seem to answer the "why" part of the question.
So, to answer your question in particular, many philosophers don't actually believe that the world came from philosophical nothingness, and therefore seek to answer the question that follows: If something didn't come from nothing, then why does something exist rather than nothing? As for the physicists, take what they say with a healthy dose of skepticism when they discuss something coming from "nothing".
You mention the big bang, which would place the question into the realm of physics and not philosophy. There are various answers to the question, "Where did the universe come from?" in physics but I believe in general these assume it did not come from nothing (excepting the quantum definition of "nothing", which is perhaps a deflection of your question). However, the information we have about what was before our universe is very limited.
Setting aside the quantum definition and substituting the concept of "existence" for "the universe" makes the question more philosophical and less about physics. In this case, the concept of nothing does not have to refer to an actual "thing"; it refers to the opposite, of course, but this is also just a pragmatic abstraction.
Logically enough, no one has ever seen/touched/otherwise found evidence of the existence of nothing. "Nothing" is at best a poorly defined, hypothesized state that can't be proved or disproved because it is given to not be anything yet "existing before anything" or "outside anything". This is a just a semantic displacement, since I can then say, "What was there before there was nothing?" to which you could reply, "That's not what nothing means. Nothing means what there was before anything else". Believing in such a thing is an item of pure faith, there is no logical reason to believe there was ever just nothing. If all "nothing" refers to is "what there was before there was anything", what reason do you have to believe in it at all? Causality does not mean there must be a first cause, it just means things happen for a reason. Those reasons do not necessarily have a starting point in time. For example, we would say that 1 + 1 has always equalled 2 (even when/if there was only nothing). The reason why 1 + 1 = 2 does not depend on some historical event taking place which made it true.
If you reify the concept of nothing, you then create a whole set of a potentially absurd questions, such as "Why is there something rather than nothing?" and "How did something come from nothing?". These questions assume something that is pure conjecture (that it's true there was nothing before something, etc.) and any answer to them must involve attributing properties to nothing -- which is a subversion of the concept (much as I said the quantum definition might be a deflection of your question).
The physicists 'nothing' is a special state called the 'vacuum state'. It certainly isn't the philosophical nothing as SteenJobs pointed out in his excellant answer.
As a provocative thought one could take as two axioms:
nothing comes of nothing
Nothing is easier to establish metaphysically.
One then deduces that reality must be non-reality. This ties in with the notion of maya; personally and probably mistakenly I tend to think that maya signifies that there is more to reality than meets the senses, which is provably true.
The Hindu scriptures do not teach creation. You cannot create something out of nothing. They state that the universe is projected out of Brahman which is neither being nor non-being, pure consciousness. They also teach that the universe is only one in a series of cycles, which have been going on infinitely before and will go on infinitely in the future. The universe comes to a state of quiescence between cycles.
Brahman being consciousness, the universe projected out of Brahman is only consciousness. We perceive it as we do through Maya. We perceive Brahman as the universe. But we are part of the universe; Brahman is perceiving Brahman, but wrongly through Maya.
A simple answer to that would be that it was created or brought into being by a non-created or un-caused entity. I would suggest reading into Hamza Andreas Tzortzis' intellectual argument regarding this matter. Here's the link
The concept of the actual infinite cannot be exported into the real world, because it leads to contradictions and doesn’t make sense. Let’s take the following examples to illustrate this point:
- Say you have an infinite number of balls, if I take 2 balls away, how many do you have left? Infinity. Does that make sense? Well, there should be two less than infinity, and if there is, then we should be able to count how many balls you have. But this is impossible, because the infinite is just an idea and doesn’t exist in the real world. In light of this fact the famous German mathematician David Hilbert said,
“The infinite is nowhere to be found in reality. It neither exists in nature nor provides a legitimate basis for rational thought…the role that remains for the infinite to play is solely that of an idea.”
Imagine you are a soldier ready to fire a gun, but before you shoot you have to ask permission for the soldier behind you, but he has to do the same, and it goes on for infinity. Will you ever shoot? No you wouldn’t. This highlights, the absurdity of an infinite regress and this applies to events to. Therefore, there cannot be an infinite history of past events.
Take the distance between two points, one may argue that you can subdivide the distance into infinite parts, but you will always be subdividing and never actually reach the ‘infinitieth’ part! So in reality the infinite is potential and can never be actualised. Similarly the ancient Greek Philosopher Aristotle explained,
“…the infinite is potential, never actual: the number of parts that can be taken always surpasses any assigned number.”
So if we refer back to an infinite history of past events we can conclude, since events are not just ideas they are real, the number of past events cannot be infinite. Therefore the universe must be finite, in other words the cosmos had a beginning.
In terms of existential philosophy, Heidegger referred to nothing as "the purest indeterminate possibility of everything possible". In this manner the concept of nothing is utilised in a legitimate context as the tabula rasa of being(s), as opposed to attempting to cast nothing as a physical state, (from which the universe might be imagined to emerge).
On the other side, for a physicist's opinion on the 'beginning' of the universe I would suggest Sir Roger Penrose's lecture "Aeons before the Big Bang" or this summary page: Alternate Theory of the Big Bang
"As the universe nears the end of its expansion, the remainder of its black holes will evaporate or gobble one another up, thus setting things back into a state of order. During this period, the universe would begin to revert back into a similar state it was in at the big bang, when the geometry of spacetime will become smooth again, which is in stark contrast to its current jagged form. According to Penroses' model, this will usher in the new aeon, AFTER the universe is no longer able to expand any further. So it collapses back in on itself as a highly ordered system. One that that is ready to trigger the next "big bang.'"
The multiverse theory explains your question directly. It states that the universe was created when "nothing", which is in an unstable state, sprang into equal amounts of matter and anti-matter, energy and anti-energy. When this happened, the sum of these is still equal to "nothing", so it is allowed by physics (or at least not disallowed by our current understanding of physics). This happens an infinite amount of times and thus there are an infinite number of universes - the multiverse.
Stephen Hawking, world renowned theoretical physicist, authored "A Brief History of Time" and other books which explain these concepts in detail in a way that non-physicists can understand (i.e. lots of words, few numbers and equations).
There are a few theories (physical, not philosophycal) about that reasoning. If the universe is going to slow down its expansion and it goes back to an implosion, one theory is that the universe might be pulsating in big bangs and big crunches forever. If the Universe is expanding forever, then blackholes might be the creation of new universes.
This question is a paradox, simply because the thinking is in contrasting terms. Logically one cannot conceive of "something" without framing it in a contradictive contrast to "nothing" and vice versa. The key to solving this is obviously in framing it in a way that it doesnt contradict itself.
The uncertainty principle tells us that everything simultaneously exists/doesnt exist until observed, which also applies to the observer simultaneously existing/not existing until observed. This would imply that both statements of "somethingness" and "nothingness" are simultaneously and equally true. The problem again is that this is paradoxical, human reason demands that it must be either one (something), the other (nothing) or neither, but definitely and necessarily not both.
So, "How could our universe suddenly appear out of nothingness?". Logically it never could have, "universe" appearing out of "nothingness" implies that "nothingness" caused the "universe" (something) therefore they both existed at some definitive point in reality. Personally i prefer to think of them both as parts of a whole, as neither something nor nothing are, or explain the whole. Like two necessary sides to the one coin (reality). The answer i think transcends and explains something and nothing but is neither one of them.
If you take a Kantian view of time, this question becomes a misunderstanding. The universe exists in some way that is eternal, in the Augustinian sense of 'extra-temporal'. The idea it began is merely the imposition of a human perspective on something that far transcends human experience.
We experience time, in my opinion, exactly as the accumulation of entropy, and not as some dimension along which entropy just happens to continually increase. Human memory is specialized to use increasing entropy as an encoding mechanism. So we could not do otherwise.
Consider this thought experiment, (which I think is due to Boltzmann?) If the distribution of entropy became very random, and did not accumulate as we expect, our memory mechanisms would not change. We would begin to find the world less than predictable. Things would move without continuous trace, or be present and then be absent. But we could not possibly remember the parts that involved entropy decrease, they would simply occur to us as discontinuities in objects' behavior.
Then again, as our physics gets more complete, we are beginning to see exactly those things. So, why doubt that this is what has been going on all along?
Memory gives us a perspective on the universe that linearizes its complexity in a given way. But it makes us imagine that time is an aspect of the universe itself, and that the universe therefore has a beginning and an end. That is just projection.
If we are in a part of the universe where entropy is really not very plentiful, and it tends to vary continuously, then we can expect it to continually increase as we move away from a stable point where it was exceedingly rare. (Ignoring all of the slippery language and mixed tenses involved in even imagining that.) There might have been a point of sustained perfect non-entropy, which we can project back as a beginning, but that does not mean anything other than that we depend entirely on a mechanism that might not have been possible if we 'inhabited a different part of the world'.
I would contend that we find the very early seconds of the universe hard to tease out, and apparently self-contradictory exactly because they don't exist.
I have couple of 'theories' of my own in this regard. It requires a bit of explanation what I am basing this on.
Universe exists because you cannot experience the universe that you do not exist in. So imagine there is universe that in which big bang happens and laws of physics are not just right so it just collapses in to big black hole you do not exist in that universe so you cannot experience it.
So you exist only in the universe that is just right for you to exist - not only laws of physics have to be right for life to exist, but your parents have to be in right mood at certain time (wink, wink) or you will never be asking and I answering this question to you.
Now you might ask of so there is bunch of universes and we all sit in one of them great - but that doesn't really answer my question how come all the universes came from nothing. How come anything could come out of nothing? This isn't logical!
Remember I said experience universe, so how do you know that you exist in this universe? I know question sounds stupid, but you are likely to answer this with that 'I can feel', and here comes Descartes and ruins the day. He says that only way to experience anything is through your senses and then that your senses can be fooling you all along. Then he says that only thing he can be certain that 'He thinks therefore exists' as there has to be something that is doing the thinking but there is a catch. You cannot be sure of this as logic that you are basing 'I think therefore I am' is learned (remembered) and might simply not be true.
Now why this stuff about logic and experience - well your question is based on that you have experienced all your life that logic 'works' so something appearing out of nothing breaks this. But this is all based only on your perception and past experience so you pretty much cannot work with logic on this...
This part is purely speculation. But based on MWI by Everet (
number of branches of the universal wavefunction was an uncountable infinity.) My gut feeling tells me that there must be 'infinity' e.g to anything you ask a question 'does it exist?' answer is always 'yes', and we are just being part of it...
"Energy can neither be created nor destroyed, it can only change forms".
Given this axiom within physics, it is fair to say that the opinion that the Universe came from nothing is little more than speculation without evidence.
But! If you like a read, then this is fun: http://www.sciencedirect.com/science/article/pii/S221268641300037X