This thread shall concern the logic behind the start of the universe. First and foremost, could the universe have existed forever? The answer to this is no. The universe either did not always exist or was COMPLETELY stopped until a certain point. In other words, the universe must have a beginning. This is because one can not have an infinite number of events preceding the present day. If an infinite number of events must pass before the present day is reached, the present could never be reached. Thus, the universe must have a beginning. Here is where it becomes strange. The first event of the universe must not be caused by something, or caused by something that somehow escapes the laws of order that are now firmly established. I do not know how an event can occur without a cause, so I have decided upon a cause that might escape the laws of order. This would be some sort of conscious entity. In other words, some sort of conscious creator. How can such an entity escape from the logic that establishes the need for a beginning to the universe? The only way that I see is if such an entity’s thoughts/actions existed in complete chaos. In other words, the actions/thoughts follow no laws of order. Order itself may have been an invention of this entity for the plane of existence in which we reside. I know better than to assume that such logic is perfect, which is why I am posting it here in Great Debates. I want to find the possible flaws in my logic, for this is only my own logic, if they exist before I accept it as proper proof of anything, even a beginning for the universe. So, I would hope that those with more experience in such matters will step forward with their input.
… wah?
Well, here’s a theory: Suppose the universe is not a race track with a start and a finish, but more like a wheel. So for infinity in either directions there always has been a universe.
A bit surreal, but thinking about it any more will make my brain hurt.
If time can go an infinite distance into the future, why can’t it go an infinite distance into the past? This is easier if we forget about the idea of something happening because it was caused, and just say that things happen and we don’t know why.
Thing of a mathematical function, like f(x) = x-squared. Any value from negative infinity to positive infinity is perfectly legal.
The flaw in the logic of your argument is that we can’t reach the present day from some time in the past with an infinite number of events to occur in between. But that presumes an event infinitely far back (a beginning). For any event in the past, there is a finite number of events between that even and the present day, with an infinite number of events preceding it.
Think of the negative numbers, and then tell me why the events preceding today can’t go backwards infinitely.
I think the biggest difficulty people have when discussing the fundamental philosophies of cosmology and eternity (apart from a notable lack of psychoactive substances) is that we are simply burdened with a tiny and incomplete perception of time.
There is no beginning, no end, no middle. Causality is bunk.
Classic first cause argument. No matter what you claim about the entity’s thoughts (what relevance does its chaotic thoughts have for anything anyway?), the fact remains that you are accepting something for the entity (no beggining, eternal existence) that you just got through rejecting for the universe.
The basic problem with the first cause argument is that for it to work, it’s first premise must be “everything needs a cause.” Otherwise, there is no way to ensure that the universe needs a cause, since all the knowledge we presently have is about things inside the universe, all the laws of nature come from obsrevations of interactions within the universe: we have no data on the universe as a thing itself. We don’t even know if such a conception of it is meaningful.
So, given that super-expansive first premise, there is no way to avoid the conclusion that the entity, if it exists, must also have a cause, which just puts us back at square one: the entity has utterlly failed to serve the explanatory pupose that we hypothesized it for.
Thus, if you are going to assume an uncaused entity creating the universe, then you might as well do yourself one better and assume an uncaused universe. It’s the simpler explanation.
The other problem is that the first premise doesn’t even seem true in our own universe, thanks to QM. So how can we claim that it is true about the universe as a whole?
Who are you , Xeno?
Consider the door to your apartment, or house or dorm room or cell or cage or whatever it is you live in. You can never get outdoors, you know, because in order to make it to the door you’d have to first make it halfway to the door. And in order to make it halfway to the door, you’d have to make it 1/4 of the way to the door. Since there are an infinite number of points you’d have to pass in order to make any progress towards the door, you’ll never get there.
Of course it is silly (as is your premise).
Could the universe have always been here, and itself infinitely old? In theory, yes. But the stuff of which the universe is composed seems to be of 15 billion years’ vintage or younger, or so say the astrophysicists and cosmologists.
As you are probably aware, the theory that has reigned for some time now suggests that the universe had a starting point roughly 15 billion years ago as a singularity that expanded (rapidly at first, then more slowly, continuing today).
I believe there may be new vigor in dissenting theories that suggest a steady-state or oscillating universe sort of scenario, which would suggest infinite time and infinite duration of the universe, but I’m not up on that (or how they explain the absence of 11 trillion year old stars).
But there is no logical reason the universe could not have been here forever. (In fact, the notion that it wasn’t seems traumatic and weird to me).
I have only the most elementary understanding of physics, so maybe you could explain it to me. It seems to me that the forward arrow of time causes a problem for Inflationists (who hold the only tenable theory to account for an eternal universe). Time and causality are synonyms. Radioactive decay is often cited as something that occurs without cause, but I’m not sure I understand that.
Isn’t it true that there are three types of radioactive decay: alpha decay, beta decay, and gamma decay? And isn’t each caused by some circumstance? These are greatly simplified, I’m sure, as my comprehension can’t accomodate more technical explanations, but is there some fundamental flaw here in my understanding?
Alpha decay: excessive repulsion is caused when a nucleus has too many protons. A helium nucleus is emitted to reduce the repulsion. The probability of transmission is nonzero, and so the alpha particle (or helium nucleus) tunnels out.
Beta decay: instability in the nucleus is caused when the ratio of neutrons to protons is too great. Because of this instability, the neutron turns into a proton and electron, and the electron is emitted. Alternatively, when the ratio of protons to neutrons is too great, positrons are emitted in much the same manner.
Gamma decay: an inordinately high state of energy in the nucleus causes the nucleus to collapse to a lower energy state, emitting a high energy photon (gamma particle).
What exactly do they mean when they say that radioactive decay is caused by nothing?
A cause is normally considered to be a preceding event. Take 1000 particles with a half life of one hour. After one hour you find that half the particles have decayed and half have not. What event caused some of the particles to decay, but not others. Remember that by definition, the particles are identical.
The fact that a particle is unstable provides a reason for the decay of a particle but there is no preceding event to “cause” a particular particle to decay at a particular time.
Libertarian, you flatter me considerably when you imply that I might be able to explain anything in physics to you.
Perhaps there are logical reasons derived from physics and what we know of the universe for saying that the universe could not have been here forever. I wouldn’t know. I meant only that philosophically, conceptually, there was no logical reason that the universe could not have been here forever.
Rsa
But isn’t the arising of instability an event? Has it been unstable forever?
Hunter
Now that you mention it, I do wonder why an infinitely old universe wouldn’t have a uniform temperature.
Maybe. The metaphysics might be weak, but it seems to me that there are compelling epistemological issues.
Time only passes while events occur. Now, let us say that a man is placed in a room. In this room is some food. This man is allowed to eat once a stopwatch has passed through an infinite amount of time. Would this man ever be allowed to eat? I don’t see how, perhaps someone can explain it to me, I can’t claim to be anything more than an amateur in such matters. Now, we face a similar situation if time itself has no beginning. Time must have a beginning. Now, this that events also have a beginning. If this is the case, how did events start? Let us leave it at that, and see where it takes us. Yes.
Stop telling time what to do! If Stephen Hawking says he doesn’t understand it well enough to say whether it has an ultimate beginning or not, I misdoubt that anybody posting here has a better grasp (although many previous posters in this thread have a better grasp of it than I do).
Qad, that was your 2000th post. You’ve reached the end of your 2nd millenium.
Congratulations!
No, I don’t think that there is an “arising of instability” as an event. Either a particle is stable or not; there is no event causing a particle to become unstable. So yes, a particle may be “unstable forever”, some more unstable than others. In other words, a particle doesn’t go from a stable state to an unstable state due to some cause, it is inherently unstable.
QM notes that paired particles can appear out of nowhere, and as far as we know, there is no cause (matter and antimatter appear, balencing each other out, and then usually collapse again). Much of QM seems to throw causality out the window, and for the life of me I can’t understand how it could possibly be proven that there was no cause: how would we ever know that we know enough to say that no unseen process was responsible?
However, given that, Victor Stenger has put forth a theory of universe creation that essentially uses QM to make a “universe out of nowhere” theory completely plausible as a possibility, at least in terms of what we currently know about physics. Because in QM things CAN appear out of nowhere (without violating the first thermo law, no less!), coupled with inflationary scenario, the entire universe could have started as a causeless QM event.
Of course, we haven’t even gotten into the problem with talking about time in conjunction with singularities. Namely, there isn’t any. Hawking has pointed out that talking about the begginning of the universe starts to become unintelligible when considering this problem: what “time” was the beginning happening in?
A lot of these questions boil down to the problem that we have no real external concept of things like “time” or “the universe.” Time is a dimension only in the sense that we can measure it comparatively. But we have no solid idea of what “it” is, or if the concept even makes sense. It may be that talking about “outside” time or “outside” the universe is as nonsensical as talking about rocks being witty, or perfection being purple. Or it may not be. We don’t even have a good basis on which to debate these issues!
But I don’t see any mystical property there. Polarity is an inherent quality of a magnet. A compass points a certain way, not because it followed an event, but because there is a nonzero probability that it will align with the earth’s poles. (We can’t be certain that it will; there may be a defect in the compass, such as an impediment blocking the needle from moving, etc.)
So if we don’t call partical instability an event, then we can’t call radioactive decay an event either, any more than we can call a compass needle pointing north-south an event. In neither case is it that something followed something else, but rather that something depended on something else. Therefore, radioactive decay is not an example of noncausation, but merely an example of inherence.
My understanding (correct me if I’m wrong) is that they don’t appear out of “nowhere”, but out of the zero-point energy field which, in sum, is greater than all nuclear energy densities combined. The so-called vacuum of space is teeming with possible propogation modes (the Zitterbewegung). If the particales ever came to rest, we could precisely calculate both their positions and velocities.
Well, I wouldn’t call it mystical, just the way the universe works. Polarity is not an inherent property in the same way that particle properties are. I can create a magnet or destroy one by heating it. I can’t do the same for the charge of an electron or the spin of a particle.
A compass points a certain way because it aligns with magnetic fields of force. Turn the compass needle 90 degrees and it will realign with the poles. There is no statistical uncertainty in this. The possibility of a defective compass is not analogous with QM stochastics. Particles do not have defects.
The point that I think that you are missing is that an event is something that can be measured. Radioactive decay certainly is an event once it happens. But prior to the decay there are no events that we can monitor to say “ah, this particle is getting ready to decay”. You can propose that there is some “hidden” cause that triggers a decay event and I can’t refute that. Perhaps there are two dimensions of time and there is some property of a particle in the second dimension of time which we can not perceive but which triggers a decay. It’s just that we have no evidence of any of this as of now, so QM is assumed to be the way that it appears to be. But who knows. 
—If the particales ever came to rest, we could precisely calculate both their positions and velocities.—
This is a good example of what I mean: it’s not clear that this statement even means anything, so how can we even debate if it is possible. Particles? Come to “rest”?
—The so-called vacuum of space is teeming with possible propogation modes (the Zitterbewegung).—
Yep: but how is that not particles appearing without cause in as good as “nothing” as we can possibly get (a pumped empty vacuum)
Thanks, Rsa and Apos, for your candid responses. I hold certain philosophical objections to them, but I won’t burden you with those here. Suffice it to say that nothing illustrates the fact that science is a branch of philosophy quite so well as quantum theories and their interpretations.