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Kalam cosmological argument & Refutation

  1. Aug 3, 2010 #1
    Anyone familiar with the Kalam cosmoligical argument, and has a valid refutation.

    [I have one, will post it later on]

    For Kalam cosmological argument, see Wikipedia
     
  2. jcsd
  3. Aug 3, 2010 #2

    disregardthat

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    Well, it is my understanding that the Big bang is not the 'beginning of the universe' in any ontological sense, at least no theory supports that.
     
  4. Aug 3, 2010 #3
    True. In any case the BBT itself does not claim that. The problem is however that in popular narrations about the BBT, it is often been depicted as if that would be the case. And to add to that, some scientists have even posited that the Big bang meant the "begin of time" and that there was no "before the big bang". E.g. Roger Penrose. Although later, he retreated from that position.

    But there is also another part in the argument that is plainly wrong.
     
  5. Aug 3, 2010 #4

    disregardthat

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    The article doesn't really present his arguments in their entirety though, so it's hasty to call any of the seemingly odd positions wrong before reading the whole discussion. I don't think you should be delaying what you got on your mind any more.
     
  6. Aug 3, 2010 #5
    Ok.

    Well this Kalam Cosmological argument is put forward mainly by Mr. Lain Craig.

    His crucial argument is that past time cannot be eternal, since an "actual infinite" can not exist, hence the universe must have ""once" begun.

    So, let's examine this argument. The way mr. Lain Craig "constructs" his argument against this "actual" infinite is as follows. Imagine the time line, and place somewhere the point "now". Now, he argues, there can not have elapsed an "actual infinity" of time. Therefore, he argues, time must have begun.

    The only problem here is that we might ask the question: where (from what point) on the timeline, did he start counting time, in order to conclude that the time elapsed since then, can not be an "actual infinite". The point is, wherever he has placed that point, he already denies that time is infinite, and smuggles in the premise that which he was supposed to proof, namely that time had a beginning. For wherever he places the point, it can of course never be an "actual infinite" amount of time prior to now. The distance between any two points on an infinite line - wherever you place the points - yields a finite distance, always, no matter how far away you place the points. Yet this does not in any way "proof" the line itself to be finite, since we can always place the points further apart, and show that there is no upper limit, with which we have shown that - indeed - the line is infinite.

    The "actual infinite" as such - as an actual amount (or duration) of time already elapsed - does not exist, since taking an actual measure of duration requires us to place two distinct points on the timeline in order to be measurable. However that does not proof time to have started at some point. Indeed, if the timeline itself is infinite, there is no such point at which time began, so we never can have a measure of the distance between that point and 'now', which is the simple consequence of the fact that we defined the timeline to be infinite (= having no start or end).

    PS.
    And as a remark. notice how Mr. Lain Craig uses the half-sided argument of Kant, and denies the other half, in which Kant exactly argues for the other side of the argument, in which he concludes that it is impossible for time to have begun ...

    PS.2
    A very similar debate was the refutation of Friedrich Engels against the "world schematism" of Herr Duhring in the Anti-Duhring, in chapter Time and Space.
     
    Last edited: Aug 3, 2010
  7. Aug 4, 2010 #6
    Looks like you've put some serious thought into this. I don't get this part though:
    How do you reconcile 'time is without beginning or end' with 'there is no infinite duration'? Are you saying its duration is entirely dependent on our measurement of it?

    I'm guessing you have/adhere to a particular theory of time which makes this argument work. Perhaps you could share that with me?
     
    Last edited: Aug 4, 2010
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