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Re: Dick-How all this got here

Posted by Cincinnatus 
Re: Dick-How all this got here
February 23, 2015 08:58PM
In Dick's OP he stated :

Quote

Big Bang theory is not a way out of this conundrum. The Big Bang doesn't say nothing existed prior or before or on the other side of the Big Bang. It merely says that all that exists now, as far as we know, was contained in a singularity at the beginning of the Big Bang. IOW, what is here now, was here then even if it was in an unbelievably teeny tiny massive state. The Big Bang really only says that today's physics cannot describe what the universe was like before it began to expand at the Big Bang. It doesn't say that it was nonexistent before that point.

Au Contraire Dick !

The BB theory and Einstein's General relativity does indeed give us a "way out of this conundrum" (though for you probably not a very satisfying one) Any massive singularity such as theorized by the BB theory would have an event horizon at or near its periphery, This means that time dialation becomes infinite and undefinable as one approaches an event horizon(due to gravitational force),and we encounter cosmic censorship (aka the so-called black hole/singularity information paradox). That is, it is impossible to see any events beyond that point in space-time.

You seem to have this old-fashioned notion that time is completely independent of space and cosmological phenomena, a notion that was shown to be false (that is - rigorously disproven) by the physics and real experimental data of the early-mid 20th century. That is why it is now referred to as space-time. Time is not an independent dimension as many philosophers still like to believe*at least not in the cosmological realm)

Fixed spelling errors - Cin



Edited 3 time(s). Last edit at 02/23/2015 09:22PM by Cincinnatus.
Re: Dick-How all this got here
February 24, 2015 01:06AM
First I probably should ask what it is in the passage of mine that you quote that you take exception with since I don't have the belief that space and time are two distinct entities that you attribute to me?
Re: Dick-How all this got here
February 24, 2015 07:53PM
Almost everything in your other post implies a naïve/absolutist view of time. Your statement that I quoted "today's physics cannot describe what the universe was like before it began to expand at the Big Bang" while true, does not acknowledge that it is not knowable by any means.
Sure you can assume and postulate, but strictly speaking you cannot hypothesize because any evidence is forever hidden by the EH of the BB singularity.

Could you provide me with some answers that may vindicate you.

Tell me this. as an observer, what do you think one would see as an object approached the event horizon of a black hole ?

Does time pass at the same rate at all points in the cosmos ? On what factors (that we know of thus far) does it depend and why ?

Can you explain special and general relativity in terms of their temporal implications ?
Sam
Re: Dick-How all this got here
February 24, 2015 08:35PM
The newest theory postulates there was no singularity. What would this discovery say about time-space, iyo, Cin?
Re: Dick-How all this got here
February 24, 2015 09:26PM
Cin wrote: Almost everything in your other post implies a naïve/absolutist view of time. Your statement that I quoted "today's physics cannot describe what the universe was like before it began to expand at the Big Bang" while true, does not acknowledge that it is not knowable by any means.

Because GR implies that time began at or immediately after the BB, it's difficult to speak about what preceded, was prior to, was before, or lay on the other side of the Big Bang because all such terms imply temporality. What terms do you suggest we use to talk about that possibility?

I think you mentioned in a previous visit to the board that you are a theoretical physicist (unless I'm confusing you with another of our infrequent visitors); assuming that's correct, I am (as is Sam, too, it seems) very interested to know what you think about this:

[www.sciencedirect.com]

. . . from the above link:

Next, to examine the presence or absence of past singularities, we write Eq. (7) as


equation(8)


H ˙ =F(H),



and from which the age of the universe as

equation(9)


T=∫ 0 T dt=∫ H 0 H P dHF(H) ,


where H 0 signifies the current epoch. For the ordinary FRW universe with no quantum corrections of the above type (i.e. ϵ 1 =0 ), F(H)=−(3/2)(1+w 2 )H 2 , the density and H→∞≡H P in the past (big-bang singularity), where |H ˙ |→∞ as well, and we get

equation(10)


T=23(1+w) 2 H 1 ,


which once again, is finite. Now if corrections to the classical FRW model changes the nature of the function F(H) (e.g. the degree of the polynomial), such that now neither H nor H ˙ diverges, then if H P signifies the nearest fixed point in the past, such that F(H P )=0 , we approximate F(H)=F (n) (H P )(H−H P )n near the fixed point, the region which contributes most to the integral, and obtain [35]

equation(11)


T=1F (n) (H P ) ∫ H 1 H P dH(H−H P ) n →∞,


signifying a universe without a beginning. This is precisely what is expected from the no-focusing of geodesics and the quantum Raychaudhuri equation. For example, for Eq. (2), it can be easily shown that the sign of the quantum correction (H 4 ) term is positive (i.e. opposite to the classical, H 2 term), for −0.52≤w≤5.27 , which covers most of the physically interesting range, including w=w R =1/3 (radiation), which is most relevant for the very early universe, and also non-relativistic matter (w=w NR =0 ). The situation is depicted in Fig. 1, where it can be seen that in the above range of w , H P is indeed finite, and therefore T is infinite from Eq. (11). Thus, the second quantum correction in the Friedmann equation gets rid of the big-bang singularity.



Thus, after applying a few quantum correction terms, this seems, as it says, to eliminate the BB singularity, no? Or is there something here we're missing?
Sam
Re: Dick-How all this got here
February 24, 2015 10:17PM
No beginning = no foundation = no foundational being = no godthings.

Cin, People like to point out that quantum physics lends credence to metaphysics to determine what is rational to believe and what's not. When something weird, unexpected or unpredicted happens is it rational to believe it could have been a god responsible like our resident agnostics seem to believe? Metaphysics seems to support the belief that anything conceivable in the human mind is possible. I don't think that's true. Do you?
Re: Dick-How all this got here
February 25, 2015 12:18AM
Yep. No beginning to the universe, *poof!* no Kalam cosmological argument, either. Not that many philosophers thought that argument was sound to begin with, now there's little doubt it's not.
_
Sam
Re: Dick-How all this got here
February 25, 2015 12:45AM
Philosophy vs. Science = Possibility vs. Probability. This is the fundamental difference between us strong atheists and everyone else. They love science/probability and use it for gaining knowledge every minute of every day but give special case exceptions to something they made up out of thin air and the kicker is that "they" all each have a completely subjective idea of what that superdupergodthing might be like, lol. A most impractical way to view the world. And not just impractical but dangerous because it is so divisive. There is no value to wasting brain power on godthings much less on how to keep other people's godthings off my stuff. Smart people should be helping to get rid of magical thinking and superstition but instead try and try and try to keep it alive. Why? Lots of psycho/social reasons...
Sam
Re: Dick-How all this got here
February 25, 2015 07:14AM
If someone says something is possible, it's the same thing as saying it's not impossible, not logically self-contradictory. The only way someone can say something is possible is to know everything there is to know about the thing to be certain it is not self-contradictory. Therefore, godthings are impossible to exist because no one can know anything much less everything about it to be able to be certain it is not self-contradictory. If godthings are not possible, why are there still believers and agnostics? Because they want to believe, that's why.
Re: Dick-How all this got here
February 28, 2015 03:50AM
Quote
Sam
No beginning = no foundation = no foundational being = no godthings.

Cin, People like to point out that quantum physics lends credence to metaphysics to determine what is rational to believe and what's not. When something weird, unexpected or unpredicted happens is it rational to believe it could have been a god responsible like our resident agnostics seem to believe? Metaphysics seems to support the belief that anything conceivable in the human mind is possible. I don't think that's true. Do you?

Seriously Sam ?
Of course not. I can conceive of unicorns, hobbits, Zeus, Athena, Yahweh and any number of other imaginary things...that doesn't in any way mean nor imply they exist in reality. The key words there are "imaginary" and "belief"? Though the word "belief" has for some a stronger association with it (that is reality)

Dick,

Nice cut and paste job. Neither you nor the site you ref provides much explanation of what your terms represent, though it was an interesting read. That itself betrays that you probably do not understand what you just posted nor are you really any sort of theoretical physicist. Nor did I ever say I was such in the present, though I did study and major in it in my undergrad days. Nice try though.

But given the observed red-shift of distant galaxies, I would have to imagine that if the cosmos were indeed infinitely old, that heat death would have happened by now, and we wouldn't be posting this. How do you explain that ?



Edited 1 time(s). Last edit at 02/28/2015 04:12AM by Cincinnatus.
Sam
Re: Dick-How all this got here
February 28, 2015 04:35AM
I agree, Cin, but the key word in my question to me is "possible". Because we can conceive of a unicorn, does that mean that unicorns possibly exist? Agnostics here (and theists everywhere) believe anything that can be conceived possibly exists, even the god of the bible, fairies, and cows jumping over the moon. They believe it's all possible. I was most interested in what you think quantum mechanics has to do with metaphysics.

I don't think Dick is being contrary or claiming to be a theoretical physicist. I think he is trying to get a handle on the new theory from a resident "expert" and maybe learn what implications it might have for how we think about (space)time and ultimately "how all this got here".
Re: Dick-How all this got here
February 28, 2015 06:06AM
Of course it was a cut'n'paste job, dumbass. That's the reason I provided a link to the paper.

So you have no take at all on the potential implications of this equation? Sheesh, some help you were.

Wonder whatever happened to yar? I would love to hear what he thinks about this.
Sam
Re: Dick-How all this got here
February 28, 2015 07:36AM
Yar! That was way back when you were Go, I think. You should go back to that name. Don't worry, tho. You will always be Dick to someone. winking smiley
Re: Dick-How all this got here
March 01, 2015 09:37AM
Correction: a dick

. . . and thank you for pointing that out! smiling smiley
Re: Dick-How all this got here
March 02, 2015 04:59AM
Quote
Dick
Of course it was a cut'n'paste job, dumbass. That's the reason I provided a link to the paper.

So you have no take at all on the potential implications of this equation? Sheesh, some help you were.

Wonder whatever happened to yar? I would love to hear what he thinks about this.

Had you read my post more carefully, you would see that I did give you an opinion, that it fails to account for at least one thing, and a few others. And the link does not explain the terms nor the reasoning why we should apply QM , normally used for molecular,atomic and sub-atomic phenomena to the cosmic scale. Without those explanations, it reads as little more than an interesting hypothesis. It is iinternally consistent on some issues, but doesn't seem justifiable without more explanation.

But if we consider it to be valid, do we not now have the infinite regress issue back again ? (another potential issue ?)

PS. Perhaps if you weren't such "a dick" in your responses you would get better and more civil responses in kind.



Edited 1 time(s). Last edit at 03/02/2015 05:02AM by Cincinnatus.
Re: Dick-How all this got here
March 02, 2015 06:28AM
Quote
Sam
I agree, Cin, but the key word in my question to me is "possible". Because we can conceive of a unicorn, does that mean that unicorns possibly exist? Agnostics here (and theists everywhere) believe anything that can be conceived possibly exists, even the god of the bible, fairies, and cows jumping over the moon. They believe it's all possible. I was most interested in what you think quantum mechanics has to do with metaphysics.
quote]

To answer question, simply put QM (quantum mechanics) is a way of answering the second of the 2 fundamental questions of metaphysics. That is, "1-what is there?" and "2-what is it like". QM applies wave equations to explain and predict the behavior of atomic and sub-atomic particles. I was always formally taught that it generally is not useful for things on the cosmic scale.

Also, I question your assertion that an agnostic would believe that "anything that can be conceived possibly exists". Sure it exists as an idea, insofar as one believes in the existence of an idea, a concept or that a mathematical function. But existence in physical reality is not the same. For that we need physical evidence.
Sam
Re: Dick-How all this got here
March 02, 2015 06:51AM
Are you an atheist, Cin? If so, weak or strong?
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