Posted by:
Jesus Smith
(
)
Date: November 06, 2010 06:54AM
I missed the fiery discussion over Hawking (
http://exmormon.org/phorum/read.php?2,26707,26740#msg-26740 ) because I was working far from civilization in the desert. Hat-tip to Cabbie for emailing me about it.
Hawking is reported in this blog to have backpeddled a little in a "it depends on what 'is' is" fashion from his Nietzche-esq statement that god is dead. Apparently, god is physics. I guess that makes us physicists the new clergy.
http://puntodigital.com/stephen-hawking-god-physics/224448/Quote:“I never said that God does not exist. God is the name people use to explain why we are here. I think we are here thanks to the laws of physics and not due to an impersonal relationship with a impersonal God."
I happened to have an ebook version of The Grand Design, which I am planning to read soon. I glanced through it tonight and found in chapter 6 (the one called something like "Choosing the universe") that Hawking gives his view of why a mystical god is unneeded. Or at least, this is one of the views. There may be others in the book I've yet to read.
Quote (from the ebook, so no page numbers):
"If the origin of the universe was a quantum event, it should be accurately described by the Feynman sum over histories. To apply quantum theory to the entire universe--where the observers are part of the system being observed--is tricky, however. ... [description of photon at double slit exp] ... One can also use Feynman's methods to calculate the quantum probabilities for observations of the universe as a whole. There is no point A, so we add up all histories that satisfy the no-boundary condition and end at the universe we observe today. In this view, the universe appeared spontaneously, starting off in every possible way. Most of these correspond to other universes. While some of those universes are similar to ours, most are very different. ...many universes exist with many different sets of physical laws. Some people make a great mystery of this idea, sometimes called the multiverse concept, but these are just the different expressions of the Feynman sum over histories."
Here's my best layman's attempt to explain the above: Hawking alludes to the idea of quantum events generating something from randomness or nothingness. Particles appearing from the vacuum and that sort of thing. Then he describes the prototypical single photon at a double slit experiment (deleted from the quote). Which slit does the photon go through? Both. It is the sum of all possibilities/histories until it reaches the detection point (reality). He apparently is arguing that the universe is the same. It started (well, he doesn't say started, he says there is no point A; what he means by saying there's no boundary is confusing to me) as a quantum event and ended up where we are at this very moment. In between is the sum of possibilities or histories. This description means Hawking is selecting one interpretation of QM over others. The most accepted is the Copenhagen. He's pushing for a different one, the multiverse.
My quick take on this:
First off, multiverse is a hypothesis. Just like many other interpretations of QM. A good table summarizing the more popular interps are here:
http://en.wikipedia.org/wiki/Interpretations_of_quantum_mechanics#ComparisonPhysicists still heavily debate which interpretation is correct. In fact, one of the last things Einstein worked on was a thought experiment with Rosen (The EPR thought exp) to show which is more 'real' relativity or quantum mechanics (because QM implies faster-than-light action). Sciencenews just put up an article about the 'dispute' of these interpretations.
http://www.sciencenews.org/view/feature/id/65056/title/Clash_of_the_Quantum_TitansI'm a fan of Copenhagen and de-broglie's/bohm's. Some of the ones with commonality to multiverse are the many-worlds/mind and consistent histories. There might be some others too.
Second off, Hawking assumes no boundary at point A (which to me sounds like he's saying there's no beginning, or perhaps no end boundary), and I haven't seen his rationale for that. It appears to just be a guess for lacking more info. He argued something different earlier in his career.
Third, I've seen the Feynman path integrals (some of the math he references) used for interpretations not aligned with the multiverse.
The bottom line is, Hawking is expressing that there is a logical hypothesis (yet lacking evidence for support) that would allow the spontaneous generation of the universe.
Ok. Shrug. Other hypotheses have just as much (zero) support, and can claim to have a "super-intelligent conscious" mind at the helm. (Many minds, Relational interp, etc can be used to justify a 'higher intelligence', though not required as defined by religions).
In that blog article, another fun Hawking quote is this one: "According to Hawking, the brain is a computer and our reasoning is a program. '' It will stop working when the computer turns off. Theoretically, it could be recreated in a neural network, but that’s too complicated, because it would involve all the memories of a person,'' he said."
Well, that's just a cosmologist giving his opinion on neuroscience. We don't know for sure. But absent any evidence that consciousness survives death, it is the default position.
I'm agnostic on all of this. I just don't know. The one thing that stands out pretty clear to most rational people, whether god started the ball (dice?) rolling, he/she/it/they is/are not relevant in any currently measurable way as an active theistic deity.