Vacuum stability in heterotic M theory

Abstract

The problem of the stabilization of moduli is discussed within the context of compactified strongly coupled heterotic string theory. It is shown that all geometric, vector bundle and five-brane moduli are completely fixed, within a phenomenologically acceptable range, by non-perturbative physics. This result requires, in addition to the full space of moduli, non-vanishing Neveu-Schwarz flux, gaugino condensation with threshold corrections and the explicit form of the Pfaffians in string instanton superpotentials. The stable vacuum presented here has a negative cosmological constant. The possibility of "lifting" this to a metastable vacuum with positive cosmological constant is briefly discussed.

Inflation and String Theory

“…One problem with this modular picture, as we explain in detail in §4.2, is that geometric separation does not imply complete decoupling of two sectors. At the very least, the supersymmetry-breaking sector interacts with the remaining fields by its coupling to the overall compactification volume V: any source S of positive energy 33 in the four-dimensional theory must be negligible in the limit V → ∞, and so must enter the Lagrangian as [292,293,[401][402][403][404][405][406][407][408][409][410], while for proposals in the heterotic string, see [411][412][413][414][415]. See [416] for an early construction of de Sitter vacua in supercritical string theory, i.e.…”

Flux, gaugino condensation, and antibranes in heterotic M theory

“…One of these can always be set to zero, if so required. 3 In terms of these new quantities, the complete square in the five-dimensional action simply becomes a kinetic term for X α , as can be seen using equation (1). Therefore, the only place where the condensate explicitly appears is in the Bianchi identity of X α .…”

“…The second term is the expansion parameter which controls the size of the CalabiYau Kaluza-Klein modes. Using (3) and (12), we see that…”

“…For now, we simply note that the harmonic flux includes a (0, 3) form component Gābc y , which can give a non-zero contribution to a superpotential W GV W ∝ M 7 Ω ∧ G when combined with the holomorphic (3,0) form Ω. The reader should not think that the above index structure considerations imply that only one of the 2(h 2,1 + 1) flux parameters, that corresponding to the H 0,3 component, contributes to the superpotential.…”

Stable and metastable cosmic strings in heterotic M-theory

“…For the purposes of this paper they can be taken to be constants. The coefficient τ 1 was estimated in [19] and found to be of order 250. Since we do not have any five-branes wrapped on cycles whose area is controlled by ReT 2 , the term W np (T 2 ) is given by…”