loop quantum gravity said:
anyway, thanks for the names' list...
it is a thought-provoking question----glad you asked. Another name that comes to mind is Don Marolf. He has done string research and also has been co-author on several key LQG papers.
but there is another aspect to this besides the people-overlap.
there is an area of research where the two approaches are so interconnected that one cannot really draw the line.
at a certain point one cannot be sure if he is doing Loop research or string.
or at least making a sharp distinction might raise controversy.
you can see this emerging if you can take the time to go over the recent (largely incomprehensible to me) paper by the prominent stringtheorists
Dijkgraaf, Neitzke, Vafa, Gukov that I cited in another thread. At some places they point to where they think Loop methods could play a role in what they call "topological Mtheory". I will try to find a quote. there is a strong example of this in their conclusions right at the end. Maybe i can find it.
yes the thread is
https://www.physicsforums.com/showthread.php?t=67709
the paper is mentioned in post #4 there
http://arxiv.org/abs/hep-th/0411073
a sample quote would be on page 56, section 10 "directions for future research"
----quote Dijkgraaf, Vafa et al----
Another natural question we have raised relates to the interpretation of the topological M-theory: does it indeed count domain walls? This is a very natural conjecture based on the links we found between form theories of gravity and the counting of black hole states. It would be important to develop this idea more thoroughly. Another question raised by our work is whether one can
reformulate the full M-theory in terms of form theories of gravity. This may not be as implausible as it may sound at first sight. For example, we do know that N = 2 supergravity in 4 dimensions, which is a low energy limit of superstrings compactified on Calabi-Yau manifolds, has a simple low energy action: it is simply the covariantized volume form on (4|4) chiral superspace [74]. In fact, more is true: we could include the Calabi-Yau internal space as and write the leading term in the effective action as the volume element in dimension (10|4). The internal volume theory in this case would coincide with that of Hitchin. Indeed, this is related to the fact that topological string amplitudes compute F-terms in the corresponding supergravity theory. Given this link it is natural to speculate that the full M-theory does admit such a low energy formulation, which could be a basis of another way to quantize M-theory — rather in tune with the notion of
quantum gravitational foam.
----end quote----
LQG is the most notable case of a form theory of gravity. I think there is a nonspecific reference to LQG/spinfoam here, which I have boldfaced to make more visible.
