Moduli stabilization in higher dimensional brane models

Abstract

We consider a class of warped higher dimensional brane models with topology M × Σ × S 1 /Z2, where Σ is a D2 dimensional manifold. Two branes of codimension one are embedded in such a bulk space-time and sit at the orbifold fixed points. We concentrate on the case where an exponential warp factor (depending on the distance along the orbifold) accompanies the Minkowski M and the internal space Σ line elements. We evaluate the moduli effective potential induced by bulk scalar fields in these models, and we show that generically this can stabilize the size of the extra dimensions. As an application, we consider a scenario where supersymmetry is broken not far below the cutoff scale, and the hierarchy between the electroweak and the effective Planck scales is generated by a combination of redshift and large volume effects. The latter is efficient due to the shrinking of Σ at the negative tension brane, where matter is placed. In this case, we find that the effective potential can stabilize the size of the extra dimensions (and the hierarchy) without fine tuning, provided that the internal space Σ is flat.

On dilatons and the LHC diphoton excess

“…This corresponds to the brane world models where the brane potentials are tuned to the bulk superpotential, for which it is well known that there are massless moduli corresponding to the positions of each brane (see e.g. [35,36]). Without supersymmetry though, these are clearly tuned models.…”

Vacuum currents in braneworlds on AdS bulk with compact dimensions

“…Motivated by these issues, the investigations of the Casimir energy and related forces on AdS bulk have attracted a great deal of attention (see, for instance, the references in [31]). The Casimir effect in higher-dimensional generalizations of the AdS spacetime with compact internal spaces has been discussed in [32][33][34][35][36][37][38][39].…”

Moduli stabilization in a de Sitter compactification model

“…A natural way to proceed is to use zeta regularization techniques. Defining the following generalized zeta function 15) where λ are the eigenvalues of the Laplacian on dS n+1 , the effective potential (3.14) can be expressed as 16) where b is the radius of a (n + 1)-dimensional sphere S n+1 . The task is then to find the analytically continued values of the zeta function and its derivative, ζ a (0) and ζ ′ a (0).…”

“…[10,11,12,13] (Related work is that of Refs. [14,15,16,17,18]). This method is valid over the whole parameter space and serves as a general way to compute the one-loop effective potential.…”