TY - JOUR

T1 - Extra-dimensional curvature suppression of the effective four-dimensional vacuum energy density

AU - Guendelman, E. I.

PY - 2012/5/21

Y1 - 2012/5/21

N2 - Considering a very large number of extra dimensions, N → , we show that in the effective four-dimensional picture, to leading order in N, both the cosmological constant in N + 4 dimensions and the curvature of the extra dimensions (curved as spheres) give the same type of contributions. Furthermore, in this limit, the extra-dimensional curvature naturally suppresses the effect of a positive cosmological constant, so that the resulting effective potential governing the vacuum energy in the effective 4 D picture has a leading 1/N dependence (i.e. vanishing in the large N limit). We can understand qualitatively this effect in a heuristic picture by thinking that both visible and extra dimensions have an equal sharing of the curvature caused by Λ. In this case when increasing the overall number of dimensions by adding N extra dimensions, then if N is large, the visible dimensions do not have to curve too much; hence, a small four-dimensional vacuum energy follows. In the large N picture, the potential can also be stabilized by a small (i.e. vanishing at large N) expectation value of a four-index field strength.

AB - Considering a very large number of extra dimensions, N → , we show that in the effective four-dimensional picture, to leading order in N, both the cosmological constant in N + 4 dimensions and the curvature of the extra dimensions (curved as spheres) give the same type of contributions. Furthermore, in this limit, the extra-dimensional curvature naturally suppresses the effect of a positive cosmological constant, so that the resulting effective potential governing the vacuum energy in the effective 4 D picture has a leading 1/N dependence (i.e. vanishing in the large N limit). We can understand qualitatively this effect in a heuristic picture by thinking that both visible and extra dimensions have an equal sharing of the curvature caused by Λ. In this case when increasing the overall number of dimensions by adding N extra dimensions, then if N is large, the visible dimensions do not have to curve too much; hence, a small four-dimensional vacuum energy follows. In the large N picture, the potential can also be stabilized by a small (i.e. vanishing at large N) expectation value of a four-index field strength.

UR - http://www.scopus.com/inward/record.url?scp=84860665923&partnerID=8YFLogxK

U2 - 10.1088/0264-9381/29/10/105007

DO - 10.1088/0264-9381/29/10/105007

M3 - Article

AN - SCOPUS:84860665923

VL - 29

JO - Classical and Quantum Gravity

JF - Classical and Quantum Gravity

SN - 0264-9381

IS - 10

M1 - 105007

ER -