We Have A Testable Candidate For The Theory Of Everything!

For the past few hundred years, many scientists have tried to understand the relationship among the fundamental forces (gravity, electromagnetism, weak nuclear force, and strong nuclear force) and the various particles (electrons, quarks, etc.) that make up the matter in the Universe. The hope is to understand all these various things as aspects of one single unified idea. This is called searching for unification or searching for ToE (Theory of Everything.)

For the past twenty years, the mainstream idea about unification is the String Theory/M-Theory. I think the extremely large number (1 followed by around 500 zeroes) of possible versions of String Theory is a fatal flaw (since it's likely impossible to find experiments that rule out all versions) and blogged about a book that points this out.

Imagine my pleasure in seeing that there's an alternative candidate that can be either verified or refuted. I saw a headline called "Surfer dude stuns physicists with theory of everything" and my first reaction was he is probably another crank. Anyway, quite a few good physicists think the paper is not a joke, so I went to download it here (An Exceptionally Simple Theory of Everything).

My higher theoretical physics is extremely rusty but the paper sounds plausible. Most importantly, we will be able to check whether it's right or wrong in the next few years when suitable experiments are performed. From the paper:

The theory proposed in this paper represents a comprehensive unification program, describing all fields of the standard model and gravity as parts of a uniquely beautiful mathematical structure. The principal bundle connection and its curvature describe how the E8 manifold twists and turns over spacetime, reproducing all known fields and dynamics through pure geometry. Some aspects of this theory are not yet completely understood, anduntil they are it should be treated with appropriate skepticism. However, the current match to the standard model and gravity is very good. Future work will either strengthen the correlation to known physics and produce successful predictions for the LHC, or the theory will encounter a fatal contradiction with nature. The lack of extraneous structures and freeparameters ensures testable predictions, so it will either succeed or fail spectacularly. If E8 theory is fully successful as a theory of everything, our universe is an exceptionally beautiful shape.

Hey, maybe I will see warpdrives before I die after all!

"Not Even Wrong" And How My Mathematical Mediocrity Accidentally Saved Me A Lot Of Grief

Not Even Wrong* by Peter Woit is a book about how string theory monopolizes the attention and resources of theoretical particle physics for the past 20 years while producing no testable prediction to decide whether the idea is correct or not. I have just finished reading the book this week, and found it to be a very interesting book. Aspiring physic students should definitely read it before they choose their research fields**.

To understand the overview of the history of particle physics in the first half of the book, the reader should be a layman interested in physics or has at least an undergraduate science training. However, any rational, scientifically-minded person can follow the conclusion of the book. The most striking passage of the book that I found is:

"Now matter how things turn out, the story of superstring theory is an episode with no real parallel in the history of modern physical science. More than twenty years of intensive research by thousands of the best scientists in the world producing tens of thousands of scientific papers has not led to a single testable experimental prediction of the theory. This unprecedented situation leads one to ask whether one can really described superstring theory research as scientific research in the field of physics. This question tends to take on two different forms. One form of the question that many physicists ask is whether superstring theory should not perhaps be described as mathematics rather than physics. A second form of the question asks whether the theory is a science at all."

In 1990, I was a junior physics undergrad at Caltech and was contemplating whether I should go into theoretical particle physics or not. At the time, string theory seemed to be the only game in town for particle theorists who want to have any chance of a tenure professorship. After a lot of investigation, I just could not see the internal beauty of the theory as claimed by many, many smarter people advocating the theory. To me, with my mediocre mathematical skills, it just seemed very complex and difficult, with no accessible physical interpretation. I decided to go into biomedical physics and software instead and followed the theoretical ideas from the sideline.

That decision turned out to be good for me in the long run. I had enough time to explore a wider range of human knowledge such as computer science, evolution, history, signal processing, statistical inference, handgunning, and Buddha's discovery. I didn't have a chance to discover the ultimate building blocks of the universe, but given that thousands of smarter people working for two decades and failing to have any testable prediction, I doubt that I would have done any better.

Well, the morals of the story are:

1. Even if you don't have great skills, you can be quite happy doing what you find personally interesting;
2. A scientific theory must make predictions that can be tested by experiments or observations. If it cannot do so, we cannot know whether it's correct or not;
3. There are infinitely many internally consistent mathematical objects. To know which one corresponds to our physical reality, we should humbly ask Nature through suitable experiments;
4. Monoculture, for living things and for ideas, is harmful. For monocultured living things, a single strand of virus can wipe out the entire population. For monocultured ideas, a fashionable but misguided idea can do a lot of damages, even to geniuses among us.

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*The famous physicist Wolfgang Pauli (of Pauli Exclusion Principle) usually proclaimed "wrong" (falsch) or "utterly wrong" (ganz falsch) when he disagreed with a scientific idea. He reserved "That is not even wrong" (Das ist nicht einmal falsch) for vague ideas that could not be confirmed or refuted, and therefore did not belong in science.

**My first blog post was about options that a highschool/college student might want to know about.