On the boundedness of effective potentials arising from string   compactifications
  We study effective potentials coming from compactifications of string theory. We show that, under mild assumptions, such potentials are bounded from below in four dimensions, giving an affirmative answer to a conjecture proposed by the second author in arXiv:0911.3378v4 [hep-th]. We also derive some sufficient conditions for the existence of critical points. All proofs and mathematical hypotheses are discussed in the context of their relevance to the physics of the problem. 
Marcelo M. Disconzi, Michael R. Douglas, Vamsi P. Pingali
math-ph gr-qc hep-th math.DG math.MP