Quantum information and tests of string theory:
This is an off-topic comment. But Mike Duff and others have promoted their recent very interesting work on quantum information and U-dualities in string/M-theory as tests of string/M-theory. Well, I don't think that any tests of the characteristic physics of string/M-theory or quantum gravity is being tested in this way.
However, I do agree that the work shows that a small subset of a much more powerful mathematical toolkit of string/M-theory - when interpreted a bit differently (the black holes carry an "exponentially bigger" information than the "information" substituted to the hyperdeterminants) - is directly relevant for very practical questions in quantum computing. See BPS black holes as a Hungarian quantum computer (2006) and SUGRA, black holes, and quantum information (2010).
Stephen Hawking and Leonard Mlodinow have written a new book, The Grand Design, in which they fired God from the job of the Creator.
He's no longer needed: M-theory has taken His place. Now, every physicist will realize that this is a kind of metaphor or a marketing slogan or a joke: physics and religion haven't interacted that directly for centuries. Physics doesn't operate with the term "God" and His existence. And if it talks about creation, it means something substantially different than the religious people do. The logical systems of science and religion are not compatible.
However, the physicists who actually understand the content of the new book at the technical level also know that there's a genuine justification hiding behind Hawking's "heretical" pronouncements.
At any rate, the provoking statements have abruptly catapulted Hawking and Mlodinow's new book to the first place among all the bestsellers at amazon.com - and I really mean all titles, not just the scientific titles. And in this case, I do think that Hawking kind of deserves the success, despite the superficially cheap marketing. He has quite a lot to revenge for to the non-existent God. ;-)
Nevertheless, the negative reactions began to arrive, too. First, God Himself wrote an op-ed for the Times:
God: Hawking has “ruined it for everyone”Unfortunately, the original article is behind the paywall so the believers will have to trust the second-hand testimony by Michael Brooks above - who says that he has seen the original article. ;-) In His article, God shows that He exists and explains why His mind-tapping is compatible with the constitution and all other laws (Google is also doing these things, He argues), among other things.
According to other reports, God has Alzheimer's so he omitted a few zeros in Genesis and all imperfections can be forgiven - it's just not fair to criticize him.
However, you may also obtain versions of the same articles that are not hiding behind any paywall. Here is what the union of the U.K. spokespersons of God - including the archbishop of Canterbury - wrote:
Mid-Day: Religious leaders hit back at HawkingThey say that "physics on its own will not settle the question of why there is something rather than nothing". You know, science is all about explanations while religion is about interpretations. Do I agree with these proposed methods to separate science and religion?
Well, I don't. As far as the second statement goes, you can't ever strictly separate "explanation" from an "interpretation" as long as you are trying to find correct explanations and correct interpretations. If science finds an explanation why something exists or why something looks the way it does, it also eliminates other explanations and other interpretations what those things mean. You can't do anything about it.
See also many reactions to God's and his spokespeople's opinions in The Telegraph and note that the most influential Marxists in the world came to defend their comrade God, too. ;-)
Can physics on its own "settle the question of why there is something rather than nothing"? Well, maybe it can't. But it's a physically meaningless question because the obviously correct answer is almost tautologically that "there must be something rather than nothing; otherwise nothing, and not even this question and answer, would exist".
While physics (and science) may fail to offer a "deeper cause" for similar tautologically true propositions (such as that there is something), what it can do is exactly that it may falsify some interpretations of what the existence of something implies.
And indeed, it has falsified many of them. The existence of something does not imply that a prayer will increase the chance of your winning a lottery. It's exactly the investigation of these - and, more often, other (more realistic) - hypothetical implications and relationships between propositions that science is so good at. Good science is not primarily about the Yes/No answers to strictly isolated questions. It is about observations and methods that allow us to derive answers to different questions from each other.
The creating power of M-theory
Needless to say, I agree with Hawking and Mlodinow that string/M-theory is the unifying theory that Einstein was looking for and that it also has the capability to answer all dynamical questions about the possible and likely appearance and disappearance of matter, and even space and time, from something else, from nothing, or otherwise. And about many detailed questions that arise as soon as you begin to study these issues seriously.
Another question is whether we fully understand what the theory does say about these things but it's simply not true that such questions are guaranteed by someone to stay outside the mantinels of science. The research of string/M-theory and quantum gravity has demonstrated that the topology - and, arguably, also the number of components of space - may change. And we know many rules governing closely related phenomena in detail. We don't understand others but there's clearly no "guaranteed eternal" wall that will prevent science from making further progress.
Centuries ago, Napoleon - whose own relationship to religion was somewhat ambiguous - asked a deliberately intimidating question to Pierre Laplace: "Where is the room for God in your models?" And Laplace boldly and famously replied: "I did not need that hypothesis."
Of course, Laplace's self-confidence was a bit naive because he knew nothing about the Big Bang - the moment in which the Universe began to exist, apparently out of nothing. When the Big Bang was found as a consequence of Einstein's general relativity, the philosophy of creation has been altered for decades. It may be said that the discovery of the Big Bang has partially returned God to the game.
Well, it was a somewhat modernized God who enjoys producting Planckian seeds of the universes rather than women out of Adam's ribs - but some features of the religious logic could have been preserved. For a while.
However, a part of this change was due to the new mystery - and new ignorance - about the details of the tiny, Planckian, seed of the Universe. The cosmological models based on general relativity implied that the Universe used to be so tiny that the very laws of classical general relativity broke down. They can only be trusted if the curvature is relatively small.
That's where quantum gravity comes into the game. String/M-theory - the only and arguably inevitably correct theory of quantum gravity, as Hawking and Mlodinow agree - has its own range of validity and it is literally everything. In particular, the events that occurred when the Universe was freshly created are the events in which the dynamical laws of string/M-theory are most directly applicable.
The prediction of their behavior is what string/M-theory is so good at.
Dear archbishops, you can't really prevent science from extending its reach of validity. And indeed, Hawking is right that the creation of matter but also space and time out of nothing has become a legitimate scientific question that is studied by the same, and quantitative, scientific method. And we have probably found the right framework in which these questions can be addressed at some point - to put it rather mildly. Religious apparatchiks cannot do anything about it.
Now, you may admit that the laws of M-theory could create matter, space, and time. But you may also ask: "Who created M-theory?"
From a scientific viewpoint, this is, of course, a meaningless question. A priori, M-theory is a mathematical structure that "always" exists in a Platonic world of ideas. It happens to be relevant for the physical worlds that obey its laws - such as ours. But M-theory itself is not a physical object within any space and time. So we can't talk about its "coming to the existence".
When we talk about "coming to the existence", we mean that an entity "E" did not exist before it came to the existence, but did exist after it came to the existence. Clearly, this logic presupposes the existence of time and it cannot be applied to mathematical structures such as M-theory that exist "outside space and time". So the question "Who or what created M-theory" is just a misleading bogus rhetorical exercise designed to confuse the gullible people who are ready (or eager) to get confused.
Moreover, when someone asks "Who created M-theory?," he usually doesn't ask the fully analogous question "Who created God?" Clearly, if we are comparing two possible entities that could have created the Universe, namely God and M-theory, we have to treat them fairly. So if it is legal to ask "Who created M-theory?," it must also be legal to ask "Who created God?".
In reality, the believers are more likely to burn you at stake if you ask the latter blasphemous question. Only the annoying question about M-theory is allowed to be asked, as a trick to sling mud at it, while God remains protected against questions. ;-)
But if they don't burn you at stake and if they even try to answer something to your question about God's pedigree, it's damn clear that whatever (nonsense) they will have answered, can also be used for M-theory. You just use their very explanation and change the term "God" to "M-theory" throughout this explanation. And you will get an equally meaningful - or, more precisely, equally meaningless - answer to the question "Who created M-theory?".
So this whole discussion about the "creator of M-theory" is just a biased method to obscure the fact that M-theory is indeed starting to replace God even when it comes to the creation event. I realize that this is a bitter pill to swallow for the believers. But that's how the world works.
As Feynman said in Davies' and Brown's book, Superstrings, God is hiding in places that we have not yet understood. Once we understand something, the living room for God shrinks. And that's currently the case of the birth of the Universe, too.
And that's the memo.