Hawkingfan

But you look pretty ignorant if you don't explain why you don't accept the evidence. What explanation do YOU have for the red-shifting of galaxies? What explanation do YOU have for the cosmic background radiation? What explanaton do YOU have for the nucleosynthesis of elements? What is wrong with the bb theory concerning these?

Hawkingfan

But I'm not so sure. Logical order implies chronology which concerns the psychological arrow of time which Hawking defines as "the direction in which we feel time passes, the direction in which we remember the past but not the future." And later he says, "If one assumes the no boundary condition for the universe, we shall see that there must be well-defined thermodynamic and cosmological arrows of time, but they will not point in the same direction for the whole history of the universe." And even later says, "The laws of science do not distinguish between the forward and backward directions of time." So I'm not so sure that anything can "logically precede" time, whether it's "something" or "nothing".

ex-xian

While I disagree with the hypothesis that the universe appeared out of a quantum vaccuum, for reasons other than yours, your above statement isn't correct. The mediator of the weak nuclear force appears spontaneously, travels from one proton to the other, then "vanishes" so the energy conservations isn't violated. Also, Stephen Hawking proved that radiation coming out of black holes is caused by quatum fluctuations. Particle pairs normally appear and annihilate instantly, but right on the event horizon of a black hole, the pairs appear, and one is pulled in the black hole, but the other escapes.

Quote:

MORE As far as I know the 'multiverse hypothesis' (if I remember well John Gribbin 'coined' this term) is enough well established now in spite of its detractors through the proposals of Andrei Linde and Alan Guth.Indeed it is very speculative and it's very hard to see how can it be falsified (at least now) anyway it's better than nothing.

A few months back, Scientific American published this article that discusses several possible multiverse theories that are testable. The first one is, IMO, ridiculous. They claim that if this universe is inifinte, then every possibile world exists. A world where every possible choice is actualized. Inifinte does not imply exhaustive, as any math geek can tell you. But the others are rather interesting.

Most of the people that I've talked to reject the big bang theory because of a prior philosophical idea that contradicts the big bang. I am also curious about what alternate theory you have, or what you do with the evidence referenced above.

metacristi

ex xian

From 'nothing' cannot appear 'something'.

I was not clear enough.I do not deny the possibility to 'borrow' energy as you explained above,technically speaking the universe could have appeared from a quantum fluctuation.But the 'energy' is still 'something'.The problem is that,from all what I've understood,the claim is that the Universe appeared OUT of NOTHING in a quantum fluctuation.This is a much stronger claim which does not follow logically.


Yes I know the article.The level one hypothesis is based on probabilities and on current estimations regarding the Universe.Or,we must never forget,our estimations remain simple estimations nothing more,we could make important errors (Hubble's constant for example changed value over years,even now it's value is highly contested).Moreover even if they are very accurate there is no necessity that all possible worlds really exist (or existed).Probabilities are only probabilities there is no neccessary connection between them and reality in this case.For example the odds to win the jckpot at the next 1000 draws at Lotto 6/49 (using a single ticket with 6 numbers in every draw) are (1/~14000000)^1000.Still I can win it in every single draw...The only way to test the prediction that our world exist also somewhere else is...to find it practically.

Still you must be aware that the proposed methods for 'confirmation' are not very reliable and many scientists will disagree with them.For example to state that we can infer the existence of other universes from the anthropic principle is ridiculous.Why should be so with necessity?.The 'God hypothesis' is equally acceptable,we cannot make the difference between them at this point.Even Guth in an article in Discover Magazine last year made the interesting remark that the observed realities are perfectly compatible with the hypothesis that our world is the creation of conscious beings (not necessary 'omnipotent','all good' and so on).
The only base for the above conclusion (that anthropic principle point out the existence of many universes) is that since from nothing cannot appear something and naturalism has always worked so far the multiverse hypothesis is the most probable to be true.Not a logically valid inference.Indeed tradition is never a proof or a sufficient argument.

Tyler Durden

I got bored. So I figured, why not try and answer Thomasq one more time?

The word “precede” is a predicate that entails temporality, which is why it makes it hard for me to agree. Anything that logically precedes something has to substantiate in a current , a chain of causal events.

Again, the word “order” also entails temporality. How can one conceive of an ordered state of affairs without presupposing the characteristic of time?

Incorrect. Your distinction between an “existent” and its “identity” is a poorly conceived artifact. The existence of anything is not a property of that thing, nor is its identity. An existent thing already preuspposes its particular identity. The act of identifying anything is to differentiate it from other things. However, I am not seeing the relevance of your proposal in relation to this linguistic artifact.

Non sequitur. This doesn’t follow, nor does it make any sense if you apply the same reasoning to anything else. Suppose if space ends, then it is “logically followed” by non-space. I don’t see how the concept of causality (precedes or follows) and the obverse of the conditions of possible experience have anything to do with one another.


By the way, if time is a facet of the universe, and the universe collapses in a hypothetical big crunch, is it also safe to claim that non-time logically follows time as well as precedes it?

Wyrdsmyth

So, you are saying time relies on non-time, but non-time does not rely on time. So, non-time is a necessary precondition for time, but time is not a necessary precondition for non-time. But, why should this be? Does this even make sense? Is "non-time" even a viable concept, at all? How can anything "happen" in non-time? Isn't that the same thing as being causally static, or non-causal? Note, that I am talking in the physical sense. How can there be a physical chain of causality, or a series of ordered events, within something called non-time? See, that is how it is revealed that you are surreptitiously invoking something that might be called absolute time (or higher order time, or metatime, etc.). You are asking about what happened before time, but trying not to use "before" as a temporal reference, to avoid circularity. But your use of "before" refers to physical causality, rather than abstract causality, which necessarily implies temporality. If you ask about an earlier link in a physical causal chain, then you necessarily are making a time-reference, as opposed to an abstract causal chain, such as in logic or math, when you aren't necessarily making a time-reference. And that is because, we're not just talking about logic or math, but the physical universe. That is why when you use terms like "before," "prior," and "precede" in the context of cosmology, you are always making a temporal (not just a logical) reference.

thomaq

if (A) has a beginning, then the existence of (A) is logically preceded by (not A). i dont see what is so hard to understand. in the case of time, i did not say that time "relies" on non-time. i used that terminology for the example of the existent and identity. i can rephrase that first example to say that "the identity of an existent is logically preceded by the existence of the existent, although both are temporally simultaneous." it really isnt that hard.
so, if time had a beginning, it is logically preceded by non-time, necessarily. this does not mean that non-time "caused" time. it is the absence of a cause for the shift from non-time to time which makes option (2b) (of the "naturalism irrational?") thread irrational, because as you point out, it doesnt make sense to say that non-time causes time. (option 2b presupposes that time began approx 14 billion years ago in the big bang).

but now we should probably bring this back into the other thread.

Normal

Of course you can talk about before the big bang. Does it have any relevence? Well that's debatable. Hawking seems to be of the mind that we should cut out events before T=0 because such events would be "unobservable". Is he right? Who knows. The point is time did not "begin" with our universe, time began in relation to our universe at T=0.

Kat_Somm_Faen

The short answer was already stated - time is not defined for those instances.

The point is that for the time of t=10^-43 seconds the Theory of Relativity ( General as well as Special ) fail to expain what is going on. We have no theory to explain what is going on, our current models fail. End of story. That t time up there is known as Planck Time.

There is supposedly general consensus that for the period before the Big Bang quantum mechanics should still hold but just not ordinary physics. What is supposed to exist is "quantum foam" and I assume that is also what should exist outside boundaries of the Universe ie. beyond the front of the Univers' expansion.

Hawkingfan

I saw you post this in the other thread, but I still think this is wrong. Time cannot exist without space. No space, no time. T=0 means time did not exist. 0 is not a value.
-1 is, but if you add 1, then you get nothing. 0 is not even a number. It is an integer. Don't get carried away with it. Remember that it's only use in math is as a placeholder. That's it. Time did not begin in relation to our universe at T=0. It would be T=1.