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seen Jun 27 at 12:10

I am a postdoc in mathematics, but have my degree in theoretical physics. My work is about mathematical structures motivated from quantum field theory and string theory. For more see here.


Jul
13
comment String theory and the SM spectrum
@Michael Brown, yes, I think back in the 20th century many hopes were just as irrational as many supposed debunkings are these days. It would be good if the grander theoretical physics community had a better sense of the logical foundations of its subject, such as to then be able to make objective, substantive judgements. Much of the criticism of string theory is based on confusion already about QFT (such as the common "string theory doesn't work because the perturbation series does not converge" or "because it doesn't have a unique vacuum").
Jul
12
comment String theory and the SM spectrum
It's not about being a "fan" or a "stringer". It's about logical reasoning in science. String theory might be wrong, but not because it has more than one vacuum and not because it doesn't uniquely predict the observed elementary mass spectrum. That's not a logically sensible criticism. You might as well complain that it doesn't predict your telephone number. I would like to see people concentrate and have decent arguments about string theory. Feel free to try to trash it, that's what science is about, but know some good reasons.
Jul
12
awarded  Editor
Jul
12
revised String theory and the SM spectrum
deleted 4 characters in body
Jul
12
answered String theory and the SM spectrum
Jul
12
comment String theory and the SM spectrum
Why do you even believe that mass ratios can be derived from first principles? Kepler thought for a while the ratios of the distances of the planets could be derived from first principles. That was wrong, too.
Jul
10
comment The divergence in QCD Series— How many are they, and what do they mean?
To amplify drake's answer to Graviton's question from the opposite angle: an asymptotic series can well be the perturbative expansion of a non-pertrubatively defined fundamental theory of nature. Having the asymptotic perturbation series is not yet having the "fundamental theory", but it can be a step in that direction.
Jul
7
awarded  Announcer
Jul
5
comment Realization of Witten-type topological quantum field theory in condensed matter physics
Well, the Landau-Ginzburg theory is an old model for superconductivity and the behaviour of its potential term is what gives the Landau-Ginzburg model its name. But yeah, otherwise the relation is not super-close, I agree.
Jul
5
awarded  Revival
Jul
5
answered Realization of Witten-type topological quantum field theory in condensed matter physics
Jul
5
answered What object is quantized in quantum gravity?
Jul
5
comment The General Relativity from String Theory Point of View
The principle of quantum physics underlies all of this. Within quantum physics there are fundamental and there are effective theories. Think of a simple example of the quantum mechanics of a neutron in a potenial well (say as in arxiv.org/abs/1207.2953). Fundamentally the neutron is a highly complicated QFT bound state, but neverthess its center of mass point motion is described by simple quantum mechanics.
Jul
5
answered The General Relativity from String Theory Point of View
Jul
4
comment Is String Theory proven to be finite?
I have been expanding the relevant nLab entries a little more, also adding more pointers, see here: ncatlab.org/nlab/show/…
Jul
4
comment Is String Theory proven to be finite?
Mr. Graviton, this may be a shock now: also QCD perturbation theory is divergent. See for instance this Physics.SE discussion: physics.stackexchange.com/q/30105/5603 . Every sensible QFT diverges perturbatively.
Jul
4
comment Is String Theory proven to be finite?
As the next sentence says, the perturbation series of any sensible QFT has vanishing radius of convergence. So, no, this divergence of the sum is a sign that string perturbation theory is healthy, convergence here would be unrealistic. See ncatlab.org/nlab/show/…
Jul
4
answered Is String Theory proven to be finite?
Jul
4
awarded  Critic
Jan
11
awarded  Enlightened