Can one theory explain everything?
This is the oldest objective of science. We can retrace the question to the pre-Socratics, when Thales in 585 BCE first suggested that everything was ultimately made of water, and that the apparent phases of matter were simply different states of this fundamental water, this blood of the Apsu or ichor of the gods.
What Thales was attempting was a universal theory. We have since moved on from water to the discovery of four fundamental forces: the strong nuclear force, the weak nuclear force, gravity, and electro-magnetism. Between this quartet, our understanding of the universe – however incomplete – hangs both powerfully and delicately. Can they ever be combined into a Grand Unification Theory?
Significantly, electro-magnetism was once deemed to be two separate forces, but James Clerk Maxwell, writing towards the end of the nineteenth century, united them for the scientific world.
Today we have come up with two perfectly wonderful, credible theories to tackle the nature of the universe. We have General Relativity to handle gravity, and we have the Standard Model to handle the other three. As best we can tell, both theories are correct and utterly irreconcilable with each other. It was Albert Einstein’s Holy Grail to reconcile them. He didn’t.
And so the quest continues. Yesterday in New York, seven leading physicists attended the American Museum of Natural History for the 11th annual Isaac Asimov Memorial Debate, and they discussed whether or not it was even possible to come up with the proverbial Theory of Everything.
From the article:
Many physicists say our best hope for a theory of everything is superstring theory, based on the idea that subatomic particles are actually teensy tiny loops of vibrating string. When filtered through the lens of string theory, general relativity and quantum mechanics can be made to get along
Ah yes, string theory. The radical discipline which emerged, almost out of defiance, against the scientific establishment and purported to contain the secrets to explaining everything. The hip brand of new thinking that seemed to merge science and mysticism (more on that later.)
As Brian Greene, professor of physics and mathematics at Columbia University, says, “There’s been an enormous amount of progress in string theory. There have been issues developed and resolved that I never thought, frankly, we would be able to resolve. The progress over the last 10 years has only solidified my confidence that this is a worthwhile direction to pursue.”
I will freely admit that I am a fan of superstring theory. How can you look at it and not gape at its fascinating aesthetics. It seems very Zen, the cosmological picture of simple elegance. When physicists smash particles together and get a shower of seemingly endless smaller particles, there is something enticing about a theory that states this endlessly diverse shower is nothing more than different vibration pitches of the same underlying string-like structure. I’ve attended Greene’s lectures and he is articulate and convincing — he has the Sagan touch for communicating ideas in a lucid and affecting manner.
There’s just one little problem:
Superstring theory isn’t a theory.
Since science works on theories and the ability to test those theories, string theory is a little too radical for its own good. String theory does not lend itself to being tested. It does not make quantifiable predictions. Without these important elements, it is not science by our prevailing definition. It becomes a thought experiment. A philosophy. Perhaps, even, a religion.
From the article:
Neil deGrasse Tyson, director of the museum’s Hayden Planetarium, suggested that string theory seems to have stalled, and contrasted the lack of progress of “legions” of string theorists with the seemingly short 10 years it took one man – Einstein – to transition from special relativity to general relativity.
“Are you chasing a ghost or is the collection of you just too stupid to figure this out?” deGrasse Tyson teased.
In fact, one of the chief components of string theory is that it requires 11 dimensions to work. The instant we involve higher dimensional planes, we stray into phantasmagoric territory. The addition of dimensions becomes something like spackle. Tyson’s offhand reference to ghosts is probably quite calculated and deliberate.
What do we think? If string theory is philosophy and not science, does this suggest that the tools we use are no longer practical in addressing the investigation of the cosmos? Or is it simply a matter of time before we develop those tools?