Dear Dr. Woit, Dr. Smolin, Dr. Greene, & Dr. Dawid et al. Does string theory successfully unify quantum mechanics and general relativity? Yes or no?

Peter Woit writes that Richard Dawid argues that:

we’re supposed to consider accepting (String Theory) as the final, fundamental theory of physics, a “theory” that is not just untestable, but is a “chronically incomplete” framework based on something we can never hope to define or understand.

Brian Greene disagrees with Woit and Dawid, writing in the introduction to Einstein, Albert. *The Meaning of Relativity: Including the Relativistic Theory of the Non-Symmetric Field (Princeton Science Library) *

Superstring theory successfully merges general relativity and quantum mechanics.The full explanation for how this is accomplished is involved, but here’s a rough way to understand it. By introducing strings as the fundamental ingredients, superstring theory takes the old idea of point-particles and spreads it out—stretches it out—into the new idea of tiny filaments. This spreading of points into filaments also implies that the microscopic structure of space is spread out relative to how it was envisioned (and how it was mathematically modeled in calculations) prior to superstring theory. When strings spread space at the microscopic level, the violent undulations that were the source of the theoretical conflict between quantum mechanics and general relativity, get stretched out and hence diluted. And, as detailed calculations attest, this dilution of the violent spacetime fluctuations is just enough to allow quantum mechanics and general relativity to merge into a mathematically consistent quantum theory of gravity. —Einstein, Albert. The Meaning of Relativity: Including the Relativistic Theory of the Non-Symmetric Field(Princeton Science Library) (Kindle Locations 239-247). Princeton University Press. Kindle Edition.

So who is right?

As a student of physics, I am asking, “Does string theory successfully unify quantum mechanics and general relativity? Yes or no?”

Senior physicists have a great responsibility to answer this question fully and honestly, as it may affect the careers of thousands, as well as the advancement of physics.

For the past couple decades or so, Peter Woit has been a leading critic of String Theory and the Multiverse. Perhaps nobody has blogged more about, nor thought more about, String Theory and the Multiverse. There is likely no greater expert.

Woit explicitly states that string theory as an idea of unification hath failed, writing on his blog, “**Sorry, string theory as an idea about unification has failed, conclusively.** ” Recently Woit wrote:

I don’t think “string theorists” calling themselves whatever they want is scandalous, what’s scandalous is misleading the public about “string theory”, the way Carroll and Johnson are doing.

http://www.math.columbia.edu/~woit/wordpress/?p=10600

They’ve (Carroll & Johnson) taken to heart the post-fact environment we now live in, one where if you keep insisting something is true (string theory unification is a great idea) despite all evidence, then for all practical purposes it is true.

http://www.math.columbia.edu/~woit/wordpress/?p=10600#comment-232011

Tsetrot,

Sorry, string theory as an idea about unification has failed, conclusively. Those who promote it to the public without acknowledging that “the stuff we told you about all particles and forces being vibrations of strings doesn’t work, now we just mean an untestable idea about gravitational degrees of freedom at unobservable scales which doesn’t really quite work either, but sucks less than the competition”.

Woit writes, “**Sorry, string theory as an idea about unification has failed, conclusively.**”

Woit asserts that “String Theory has no equations to solve,” writing:

This is based on the misconception about string theory that the problem with it is that “the calculations are too hard”. The truth of the matter is that there is no actual theory, no known equations to solve, no real calculation to do.

Greene writes, “**Superstring theory successfully merges general relativity and quantum mechanics.**”

If Woit is right, that string theory has no equations, then how can string theory merge general relativity and quantum mechanics, *without any equations*?

I could find no record of Woit criticizing Greene’s statements in the introduction to Einstein’s *The Meaning of Relativity*. Does Woit agree with Greene? Why does Woit seemingly spend so much time going after the Dawids and Carrolls and Johnsons who are merely bantering on blogs, while giving Greene a free pass in the introduction to Einstein’s *Meaning of Relativity*? Does not Einstein’s *Meaning of Relativity *carry more prestige, cache, and influence than a couple of bloggers?

Perhaps if Woit had focused his energy on correcting Greene’s statements in the introduction to Einstein’s *Meaning of Relativity*, string theory would have been on its way out by now? But then again, perhaps Woit yet enjoys pondering String Theory after all these decades, and he does not really wish to see the hype fade for another couple decades more?

At any rate, who is right? Forget the games and politics and teams for a moment, and answer honestly in the way you might speak Truth to a student. Who is right?

Woit writes, “**Sorry, string theory as an idea about unification has failed, conclusively.**” (on his Columbia blog)

Greene writes, “**Superstring theory successfully merges general relativity and quantum mechanics.**” (in the introduction to Einstein’s *Meaning of Relativity*)

If Greene is right, then perhaps Woit could finally find other things to blog about? And if Woit is right, then perhaps someone could correct the introduction to Einstein’s *Meaning of Relativity* before string theory can lead billions of more taxpayer dollars and thousands of more physicists down a dead end, while displacing true physicists and physics from the academy?

Brian Greene continues in *The Meaning of Relativity: Including the Relativistic Theory of the Non-Symmetric Field (Princeton Science Library)* :

Moreover, not only does superstring theory merge general relativity with quantum mechanics, but it also has the capacity to embrace—on an equal footing—the electromagnetic force, the weak force, and the strong force. Within superstring theory, each of these forces is simply associated with a different vibrational pattern of a string. And so, like a guitar chord composed of four different notes, the four forces of nature are united within the music of superstring theory. What’s more, the same goes for all of matter as well. The electron, the quarks, the neutrinos, and all other particles are also described in superstring theory as strings undergoing different vibrational patterns. Thus, all matter and all forces are brought together under the same rubric of vibrating strings—and that’s about as unified as a unified theory could be. —Einstein, Albert.

The Meaning of Relativity: Including the Relativistic Theory of the Non-Symmetric Field (Princeton Science Library)(Kindle Locations 247-253). Princeton University Press. Kindle Edition.

Woit writes, “**Sorry, string theory as an idea about unification has failed, conclusively.**”

Greene writes, “**Superstring theory successfully merges general relativity and quantum mechanics.**”

Who is right? Or is science just an endless game of politics with teams? If so, what is the best long-term physics career plan for a physics student these days–following dead-end, failed theories or criticizing dead-end, failed theories? What is the best way to score a book deal and speaking engagements?