TESTING ALTERNATIVE THEORIES OF GRAVITY USING THE SUN

[little_monkey]

In the study of gravity we are confronted with the theory of Relativity. We also know that in the region of low gravity, Newtonian physics is valid and is contained within Relativity. But what about other theories on gravity? This paper: here explores this possibility. It starts with Poisson’s equation. In case you’re not familiar with that. It is Newton’s law of gravity, using Gauss’ theorem. In the paper, it is equation (1). One of the weakness for the present theory is the coupling between gravity and matter. Those who are not familiar with QFT might wonder, what’s that? It is a way to measure the strength of an interaction. In the electromagnetic force, the charge e and Planck constant ℏ play a role, and the coupling constant is denoted by α. This idea of a coupling constant is incorporated into equatiion (3), which is equation (1) re-written with expansion terms. It uses the sun, its different core temperature profiles, deviations in the observed acoustic modes and solar neutrino fluxes to evaluate those extra terms in equation (3).

The idea is: postulate a theory, do some calculations, and this should give you something to go out in the real world to see if those results are confirmed. It goes under the notion of a prediction. This is science done in the old fashion way. With the development in the last 30 years in Supersymmetry and String Theory, it seems we were taken back into the medieval world when philosophers tried to conform the world to their ideas from their ivory tower. This paper is a good example of observation, theory, prediction, and verification.

[Zen Badger]

That's the trouble with String theory, it doesn't actually make any testable predictions.

So, elegant as it is, it doesn't really qualify as science.

[little_monkey]

The problems with ST are two folds:

(1) Experimentally, to probe at the Planck level, we would need an LHC the size of our galaxy, and a billion black holes to fuel it in energy. So present technology is ruled out.

(2) Theoretically, ST has developed such concepts as Kaluza-Klein compactification, Calabi-Yau manifolds, moduli stabilization to arrive at 10500 possible worlds. And the only claim the string theorist has is that one of those must be our world, which is not much of a claim considering the mental gymnastics one is required to do to get to that.

So all in all, ST remains in the domain of speculative science, and I'm being very generous with the word "science" here.