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Author Topic:   Big Bang or Big Dud? A study of Cosmology and Cosmogony - Origins
forgiven
Inactive Member


Message 43 of 94 (23779)
11-22-2002 5:30 PM
Reply to: Message 12 by mark24
01-31-2002 9:09 AM


quote:
Originally posted by mark24:
Regarding the lack of singularity problem. "Universes can literally spring into existence as a quantum fluctuation of Nothing. This is because the positive energy found in matter is balanced against the negative energy of gravity, so the total energy of a bubble is zero. Thus, it takes no net energy to create a new universe."
< !--UB http://www.flash.net/~csmith0/bigbang.htm -->http://www.flash.net/~csmith0/bigbang.htm< !--UE-->
So, in summary, universe begats universe. Vacuum fluctuation react with scalar fields which may/may not lead to inflation. The mass & energy of a universe being born of a quantum bubble, with a net energy of zero.
This also postulates a timeless universe.
Mark
this is interesting, i have to read more about it... but tell me, how does it jive with the 'actual infinite vs. potential infinite' problem? iow, without using magical numbers how is it we find ourselves here and now if an infinite sequence of past events can be traversed?

This message is a reply to:
 Message 12 by mark24, posted 01-31-2002 9:09 AM mark24 has not replied

Replies to this message:
 Message 44 by Primordial Egg, posted 11-24-2002 6:44 AM forgiven has replied

  
forgiven
Inactive Member


Message 45 of 94 (24018)
11-24-2002 10:09 AM
Reply to: Message 44 by Primordial Egg
11-24-2002 6:44 AM


quote:
Originally posted by Primordial Egg:
quote:
iow, without using magical numbers how is it we find ourselves here and now if an infinite sequence of past events can be traversed?
I'm not sure that I fully understand your question (what do you mean by magical nimbers?) - but I'm pretty sure that no-one's talking about traversing an infinite sequence of past events. After all, time (more correctly spacetime) began at the Big Bang. This isn't a boundary you can traverse.
PE

ok, let's assume time began (as you say above) with bb... from that very moment, time began... each subsequent moment resulted in an event... using just our history, for example, we know the gettysburg address was written in a certain time, magna carta an earlier time, etc, etc
now we can see a sequence of past events, correct? and theoretically, given your statement that time 'began to exist', we should be able to traverse these past events (after all, if you can cross them coming forward you can do the same going backwards)
*but*.. if the universe (which includes this very time of which we speak) is infinite, it's impossible to traverse the series of past events unless we use make believe numbers... and if we can't traverse a series of events going backwards, they can't be traversed coming forward... that means we'd never have reached this present event, the one we're obviously at
so my comment was meant to show that an infinite universe can't exist (without those imaginary numbers)

This message is a reply to:
 Message 44 by Primordial Egg, posted 11-24-2002 6:44 AM Primordial Egg has replied

Replies to this message:
 Message 46 by John, posted 11-24-2002 10:48 AM forgiven has replied
 Message 49 by Primordial Egg, posted 11-24-2002 12:08 PM forgiven has replied

  
forgiven
Inactive Member


Message 47 of 94 (24045)
11-24-2002 11:42 AM
Reply to: Message 46 by John
11-24-2002 10:48 AM


quote:
Originally posted by John:
quote:
Originally posted by forgiven:
unless we use make believe numbers...
Make-believe numbers? You mean imaginary numbers. It is a valid number system, not a child's game of pretend.

whew!! joz objects to imaginary numbers, preferring make believe, you object to make believe, preferring imaginary... sheesh... yes, the use of i as the square root of -1 has applications, i don't deny that... but in the actually existing universe, the one in which we find ourselves, we'd never be here if that universe is *actually* infinite, and it can be shown that it is actually infinite only by using make believe time resulting from make believe numbers... substitute imaginary if you want, that's fine with me

This message is a reply to:
 Message 46 by John, posted 11-24-2002 10:48 AM John has replied

Replies to this message:
 Message 48 by joz, posted 11-24-2002 11:50 AM forgiven has not replied
 Message 55 by John, posted 11-24-2002 3:17 PM forgiven has replied

  
forgiven
Inactive Member


Message 50 of 94 (24055)
11-24-2002 12:33 PM
Reply to: Message 49 by Primordial Egg
11-24-2002 12:08 PM


quote:
Originally posted by Primordial Egg:
quote:
*but*.. if the universe (which includes this very time of which we speak) is infinite, it's impossible to traverse the series of past events unless we use make believe numbers
Consider the set of positive integers (1,2,3,4,5...) and lets say we're sitting on the number line at 5. The set of integers is infinite but we can only go back as far as 1. So infinite and bounded by one side - have you allowed for this possibility?
i'm not sure it is a possibility... but by so assuming you seem to be saying that you can increase the number of infinite things by subsequent addition... if a set of "things" can be increased by addition, the set is potentially infinite but not actually so... see the difference? also i'm not quite clear on how a set can be infinite in one direction only, maybe you can explain this to me
take an infinite number of boxes containing playing cards... each box contains, in order, 52 cards containing all 4 suits, 52 spades, 52 hearts, 52 diamonds, 52 clubs... now let's continue this series and keep the boxes in the same relative order... if the sum total of those boxes is actually infinite, each containing hearts only would equal each containing clubs which in turn equal the sum total of ALL of the boxes...
quote:
quote:
... and if we can't traverse a series of events going backwards, they can't be traversed coming forward... that means we'd never have reached this present event, the one we're obviously at
I was with you in principle above because I thought you were talking about a thought experiment in which you could go backwards in time. To do so in reality would violate (clears throat) the Second Law of Thermodynamics would it not? I'm pretty confused here about what you mean by traversing backwards in time - not sure what you're getting at at all.
i think one of the best examples i've seen concerns an infinite set of dominoes, one of which has a big red 'X' painted on it... all are standing on end... some cause (dare we call it a first cause?) started the dominoes falling... if the set is actually infinite, there would never be a time when the one with the 'X' would be struck... in the same vein, if the universe is actually infinite, we would never be here.. *this* point in space/time would not have been traversed
quote:
quote:
so my comment was meant to show that an infinite universe can't exist (without those imaginary numbers)
Are you referring to the mathematical use of i? Its certainly a tool that would be very difficult to do without - even Feynman said that it was impossible to do quantum mechanics without their use - but the final measurements, results and predictions all involve the real - I mean, you wouldn't say that John Doe was 6 ft (4+3i)in would you? You may as well chastise physicists for using "angles".
PE
i grant its usefulness, even its validity, ok? all i'm arguing against is using imaginary numbers to form imaginary time, because there's no basis in reality for assuming it solves any of the problems inherent in an actual infinite

This message is a reply to:
 Message 49 by Primordial Egg, posted 11-24-2002 12:08 PM Primordial Egg has replied

Replies to this message:
 Message 51 by Primordial Egg, posted 11-24-2002 12:55 PM forgiven has replied
 Message 52 by Primordial Egg, posted 11-24-2002 1:31 PM forgiven has not replied

  
forgiven
Inactive Member


Message 54 of 94 (24071)
11-24-2002 3:12 PM
Reply to: Message 51 by Primordial Egg
11-24-2002 12:55 PM


quote:
Originally posted by Primordial Egg:
I think I sort of see - but under this regime the universe is only potentially infinite, no (as we could always, in principle add more to it)? I don't want to turn this into a semantic discussion (unless I've missed the point) - so can you give me an example of an actual infinite (ie an infinite which cannot be added to)? Can they exist in the universe?
right... potentially but not actually infinite... no, i've followed your posts and i know you don't play semantical games... neither do i, 'least not on purpose... as actual infinite would be something that has always existed, unbounded by space and time, and uncaused (not contingent) by definition... as to whether or such a thing can exist, we're looking at that now in 'one step at a time' thread
quote:
Took me a while to follow this example. If I've understood correctly, are you saying that exactly a quarter of the (infinite) boxes contain hearts, a quarter contain spades etc? I don't know what you mean by having an infinity number of boxes - infinity isn't a number.
ok, a set containing an infinite number of these boxes
quote:
Mathematically, let's define (actual) infinity by 1/0, so 1/4 of this would be: 1/(4*0) = 1/0 = infinity. I'm afraid I don't follow the notion of divided infinity into quarters and then summing, this shows the dangers of treating infinity as a number.
the point i was trying to make is, with a set of actually infinite "things," one in which both the individual things and the set itself are infinite, nothing can be added to or taken away... so the total of all individual things within the set would be the same as the total of all things collectively in the set... just an attempt to show that an actually infinite can't exist in space/time else no one event would be traversed
quote:
You've just described my own number line example here haven't you? Nobody's saying you're at the infinitieth domino (not that one could exist, see above) - you're on the fifth (say) - easy to see how you got there, and reachable. Time does not extend an infinite direction backwards.
actually it isn't easy to see how that point was reached, or that it's even reachable... the moment we begin counting "1, 2, 3..." we're attempting to add to an infinite set, and such a point can't be reached by either subsequent addition or subtraction.. your examples are ones of potential infinities, and that exists in real time
quote:
OK fair enough - I can't pretend that I fully understand what Hawking is getting at with his concept of imaginary time, so it would be dishonest of me to argue this point either for or against - I guess it all washes out in the maths
PE
lol who can? the man's a certifiable genius, so his concepts can't be dismissed out of hand by anyone, least of all me

This message is a reply to:
 Message 51 by Primordial Egg, posted 11-24-2002 12:55 PM Primordial Egg has replied

Replies to this message:
 Message 60 by Primordial Egg, posted 11-24-2002 3:38 PM forgiven has replied

  
forgiven
Inactive Member


Message 61 of 94 (24096)
11-24-2002 4:41 PM
Reply to: Message 60 by Primordial Egg
11-24-2002 3:38 PM


quote:
Originally posted by Primordial Egg:
This part I spectacularly failed to understand. Maybe you can correct my understanding:
-We have an infinite dominoes, the last of which(!) is marked with a "X", and the 5th with a "Y"
-we set the first domino off
- I grant you that we'll never reach X, but why should that have any bearing on whether or not we reach Y? Is there some property of the dominoes which I don't know about??
PE
the reason is, there's an infinite number preceding 'Y' just as there is between 'Y' and 'X'... if any one domino (or deck of cards or universes or whatever) can't be reached, none can... an infinite number precede 'Y', an infinite number precede 'X'...
imagine alternating numbers '1' and '2' painted on the side of each... the total number of the dominoes with '1' on the side is exactly the same as the total number with '2' on the side... not only that, the total number of those with '1' on the side is *also* the total number of the ones with both '1' AND '2' on their sides...
hey, i just thought of this... do a search for 'hilbert's hotel' when you have time... shows the problem when dealing with an actual infinite better than i can

This message is a reply to:
 Message 60 by Primordial Egg, posted 11-24-2002 3:38 PM Primordial Egg has replied

Replies to this message:
 Message 62 by Primordial Egg, posted 11-24-2002 4:49 PM forgiven has replied

  
forgiven
Inactive Member


Message 63 of 94 (24098)
11-24-2002 4:49 PM
Reply to: Message 55 by John
11-24-2002 3:17 PM


quote:
Originally posted by John:
It is very confusing. I can't get a bead on what you are actually arguing. My best guess at the moment, taken from the above paragraph, is that you do not like the use of imaginary numbers because it leads to a description of the universe as an actual infinite, which is impossible in your view?
yes, impossible since we're here and now and we've obviously traversed time events by subsequent addition... i guess i'm saying that using imaginary numbers to create imaginary time to show an actual infinite isn't an application of the use of such numbers that has any merit in the real world, since we end up in the same quandry we began with... that being, we're still in a universe in which a potential, but not actual, infinite exists
all it does is push everything away from that point in non-time when bb occurred by making all preceding non-times into actual infinites, yet at some point we magically cross over from imaginary time into real time... at this point, we leave infinity and are able to traverse time events by subsequent addition... so no matter how we do it, at some point in the chain we're in an actual infinite from which we should never even reach bb, much less now

This message is a reply to:
 Message 55 by John, posted 11-24-2002 3:17 PM John has replied

Replies to this message:
 Message 67 by John, posted 11-24-2002 11:17 PM forgiven has replied

  
forgiven
Inactive Member


Message 64 of 94 (24099)
11-24-2002 4:53 PM
Reply to: Message 62 by Primordial Egg
11-24-2002 4:49 PM


quote:
Originally posted by Primordial Egg:
I'm with you now - you were talking about actual infinities (should have noticed). I do know about Hilbert's Hotel, but never come across potential vs actual before (prob. because I never had to ). Still a novel concept for me.
But can't you use actual infinities to prove mathematically that ALL integers contain the number 3? If so, I'd be very mistrusting of any conclusions drawn from the properties of these beasts.
PE

i don't know... also, i'm not sure if proving the existence of the number 3 is the same time as *traversing* it... see what i mean? even if we can prove the existence of the domino with the red 'X' on it, we'd still have the problem of ever reaching it while playing some cosmic game of knock over the dominoes

This message is a reply to:
 Message 62 by Primordial Egg, posted 11-24-2002 4:49 PM Primordial Egg has replied

Replies to this message:
 Message 65 by Primordial Egg, posted 11-24-2002 5:03 PM forgiven has replied

  
forgiven
Inactive Member


Message 66 of 94 (24115)
11-24-2002 7:17 PM
Reply to: Message 65 by Primordial Egg
11-24-2002 5:03 PM


quote:
Originally posted by Primordial Egg:
In your past events line of reasoning - is time a steady flowing river "happening" in the background or is it an active player, which is itself embedded in the events themselves? ie do you allow for time itself to be created?
PE
eventually i hope to reach that, yes... in the other thread i'm trying to show that, given the existence of *something*, some thing has always existed... once that's established or granted or intuited or whatever, i want to move on to whether or not this always existent thing is (or can be) the universe (which includes time as well as space)... so the (at least to my mind) logical impossibility of an actual infinity existing plays a big role
to my thinking, it doesn't really matter whether one says the universe has always existed or whether one says an infinite series of inflation/deflation has occurred... the same problems present themselves

This message is a reply to:
 Message 65 by Primordial Egg, posted 11-24-2002 5:03 PM Primordial Egg has not replied

  
forgiven
Inactive Member


Message 68 of 94 (24228)
11-25-2002 12:38 PM
Reply to: Message 67 by John
11-24-2002 11:17 PM


quote:
Originally posted by John:
quote:
Originally posted by forgiven:
yes, impossible since we're here and now and we've obviously traversed time events by subsequent addition...
Move your arm an inch to the right. It just traversed an infinite number of points, or moved though an infinite number of moments of time. However hard you wish to argue that you can't get from point a to point b because you'd have to traverse an infinite number of points, the fact is that you do it all the time-- at least, according to how I understand your logic.
I've got to check up on Hawking's arguments before preceeding.

no john, you haven't... your arm traversed a potentially infinite number of points but not an actually infinite number... the fact that it arrived at *this* point proves that

This message is a reply to:
 Message 67 by John, posted 11-24-2002 11:17 PM John has not replied

Replies to this message:
 Message 69 by joz, posted 11-25-2002 12:44 PM forgiven has replied

  
forgiven
Inactive Member


Message 70 of 94 (24243)
11-25-2002 1:24 PM
Reply to: Message 69 by joz
11-25-2002 12:44 PM


quote:
Originally posted by joz:
quote:
Originally posted by forgiven:
no john, you haven't... your arm traversed a potentially infinite number of points but not an actually infinite number... the fact that it arrived at *this* point proves that
A point by definition has no length, breadth or width....
So to find the number of points that lie between 2 given points you divide the distance between them by 0 (the spatial length of the point in that direction) and you get......
Infinity....
So your wrong there bud.....

ummmm no actually i'm not wrong... your post concerns actual infinity, and to show i'm wrong you have to show how any one point can be traversed in an actual infinity... i take it you understand hilbert's hotel? if you do, where is it in error?

This message is a reply to:
 Message 69 by joz, posted 11-25-2002 12:44 PM joz has replied

Replies to this message:
 Message 71 by joz, posted 11-25-2002 1:43 PM forgiven has not replied

  
forgiven
Inactive Member


Message 73 of 94 (24255)
11-25-2002 2:24 PM
Reply to: Message 72 by Primordial Egg
11-25-2002 1:43 PM


quote:
Originally posted by Primordial Egg:
PS forgiven - I agree with (1) anyway because it fits in with what is observed - is there a need to bring actual infinity into this?
you're pretty much right on p.e. except i wasn't anywhere near anything past (1)... i know and don't argue the conclusion you posted (God being the cause) for the simple reason that someone *might* say "well i agree with everything but i think instead of God it was a pink unicorn" *grin*
the actual infinite is important insofar as it at least stops irrational arguments as to some eternal nature of the universe... however, i'm attempting to show in another thread that *something* is in fact eternal... whether or not that leads to the k.c.a. remains to be seen... it's enough for me, at this time, to have a rational discussion on the things i'm posting, one step at a time
as for your objection to #2, you'll have to help me here... when you say 'quantum reality' are you in fact assuming quantum particles "popping" into space/time uncaused and previously non-existent? if so, i don't see how that alone defeats premiss #2.. it rests on a supposition that's simply unproven (maybe even unproveable)

This message is a reply to:
 Message 72 by Primordial Egg, posted 11-25-2002 1:43 PM Primordial Egg has not replied

Replies to this message:
 Message 75 by John, posted 11-26-2002 12:33 AM forgiven has replied

  
forgiven
Inactive Member


Message 76 of 94 (24400)
11-26-2002 9:46 AM
Reply to: Message 75 by John
11-26-2002 12:33 AM


quote:
Originally posted by John:
quote:
Originally posted by forgiven:
you're pretty much right on p.e. except i wasn't anywhere near anything past (1)...'
I'm researching my 'rythmatic but chew on this in the meantime.
No webpage found at provided URL: http://www.qsmithwmu.com/infinity_and_the_past.htm

reading it now john, if i see anything to comment on i'll get back to you... in the meantime, quentin smith is one of my favorite whipping boys

This message is a reply to:
 Message 75 by John, posted 11-26-2002 12:33 AM John has not replied

  
forgiven
Inactive Member


Message 77 of 94 (24402)
11-26-2002 10:09 AM
Reply to: Message 75 by John
11-26-2002 12:33 AM


smith, in the link you gave, didn't really touch on craig's argument... here's the relevant quote:
"The collection of past events at r is a proper subset of the collection of past events at 12. Craig feels that the equivalence between an infinite set and a proper subset of that set as applied to real things and events is just not believable (p. 86). It is only unbelievable, however, if one presupposes erroneously that the definition of an infinite set of real things or events is the same as the definition of a finite set of real things or events; namely, that a set necessarily has more things or events belonging to it than any proper subset of itself. if one does not make this false presupposition, then the equivalence in question is perfectly believable."
the truth is, craig's argument is not based on the above, but on the impossibility of actually traversing an actual infinite... by offering "...a set necessarily has more things or events belonging to it than any proper subset of itself.." as a definition craig uses in support of his argument, smith misstates the case... craig, in many places and in numerous ways, has said in fact the opposite... in a library containing an actually infinite number of books, any subset of such books (being equally infinite in number), when added together, would equal not only any other subset but also the totality of all books in all subsets
if you have an infinite number of science books, of coloring books, of westerns, of mysteries, the sumtotal of each individual "subset" is the same as the sumtotal of all subsets... this is simply the nature of an actually infinite number of things
translating that to the argument smith is making re: time, craig and others have put it simply... if the universe is actually infinite, time itself is actually infinite... if time is actually infinite, the set of past events is actually infinite... however, subsequent subtraction of past events is impossible in an actual infinite
to go from the signing of the declaration of independence, backwards, traversing every noteworthy occurance in past history, and arriving at the signing of the magna carta, would prove that past events *can* be traversed... if that can be shown, it follows that actual infinity has no place in the real world, else we'd never have arrived at *this* place in *this* time

This message is a reply to:
 Message 75 by John, posted 11-26-2002 12:33 AM John has replied

Replies to this message:
 Message 78 by John, posted 11-26-2002 11:23 AM forgiven has replied

  
forgiven
Inactive Member


Message 79 of 94 (24439)
11-26-2002 2:09 PM
Reply to: Message 78 by John
11-26-2002 11:23 AM


quote:
Originally posted by John:
This seems to be based on the idea that every subset of an infinite set is also infinite. It is possible to have finite subsets of infinite sets. Take the infinite set of books. It is possible to traverse the subset of {book1,book2,book3}
don't think so john... not only are the members of each subset infinite, the sumtotal of every subset itself is infinite... not only does the sumtotal of all mystery books equal the sumtotal of all cook books, the sumtotal of both those sets equals the sumtotal of all sets... now we can equivocate on the terms, we can say "an infinite number of sets of books exist in which a finite number of cookbooks make up a subset," which is what i think you're doing here...
what that would mean is, we find ourselves in a universe of space/time in which a potentially infinte series of past events exist, and this potentially infinite series is itself a subset of an actually infinite etc etc etc... where does potential infinity end and actual begin?
our universe is a closed system of space/time in which all past events can be traversed by subsequent subtraction, making it ~actually infinite by definition
quote:
There also appears to me a contradiction in the argument. It assumes that time itself is infinite. This means that we have an infinite amount of time to traverse infinite time. I'm sticking my neck out here but, ∞ / ∞ = 1. One isn't all that hard to traverse. It seems in fact to be right now. As the man said, Be Here Now.
smith attempts a similar line, but his arguments have always been unconvincing to me... but imagine you are inside this library with the actually infinite number of books... you happen to be looking for one specific book, probably plantinga's 3 volume set *grin*... you know it's in the philosophy section (subset) of the library... you have an infinite (actually) amount of time to both find and read the books, so you start your journey....
not only would you never reach those books, you'd never reach the subset that contained them, nor would you ever traverse each point inside whatever subset you happen to start...
that isn't a really good analogy, hilbert's hotel, aristotle's stadium, and the guy who takes a year to write about each day of his life are better (tho smith attempts to show this one is wrong, his argument has been rebutted in several places)

This message is a reply to:
 Message 78 by John, posted 11-26-2002 11:23 AM John has replied

Replies to this message:
 Message 82 by John, posted 11-26-2002 7:57 PM forgiven has replied

  
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