Universe as a domain wall

Abstract

It is shown that the effective five-dimensional theory of the strongly coupled heterotic string is a gauged version of Nϭ1 five-dimensional supergravity with four-dimensional boundaries. For the universal supermultiplets, this theory is explicitly constructed by a generalized dimensional reduction procedure on a Calabi-Yau manifold. A crucial ingredient in the reduction is the retention of a ''non-zero mode'' of the four-form field strength, leading to the gauging of the universal hypermultiplet by the graviphoton. We show that this theory has an exact three-brane domain wall solution which reduces to Witten's ''deformed'' Calabi-Yau background upon linearization. This solution consists of two parallel three-branes with sources provided by the fourdimensional boundary theories and constitutes the appropriate background for a reduction to four dimensions. Four-dimensional space-time is then identified with the three-brane world volume. ͓S0556-2821͑98͒02122-5͔

Five-brane BPS states in heterotic M-theory

“…As indicated by the notation, the multiplet Φ i (0,1) has vanishing electric charge and magnetic charge Q m = 1, whereas Φ i (−1,−1) carries both electric charge Q e = −1 and magnetic charge Q m = −1. The two BPS states in the fourth row combine to form a single, N = 2 hypermultiplet, Ψ (1,2) with Q e = 1 and Q m = 2. Finally, the last two rows each correspond to a single N = 2 hypermultiplet, denoted by Ψ (1,−1) and Ψ (2,1) , with Q e = 1, Q m = −1 and Q e = 2, Q m = 1 respectively.…”

“…We denote these hypermultiplets by Φ i (1,0) , where i = 1, 2, 3. Similarly, the second and third rows each correspond to a triplet of N = 2 hypermultiplets, which we denote by Φ i (0,1) and Φ i (−1,−1) with i = 1, 2, 3 respectively.…”

“…In a series of papers [1,2,3,4,5,6,7], it was shown that when Hořava-Witten theory [8] is compactified on Calabi-Yau threefolds, a "brane Universe" theory [1,9] of particle physics, called Heterotic M-Theory, naturally emerges. This Universe consists of a five-dimensional bulk space which is bounded by two four-dimensional BPS three-branes, one at one end of the fifth dimension and one at the other.…”

Null deformed domain wall

“…16 Let us remark that the feature ∂ + β = 0 is non generic but a consequence of the simple model we have chosen. This property allows us to integrate immediately eq.…”

“…As solutions of gauged supergravity these are conjectured to be dual to the Renormalization Group (RG) flows of field theory couplings [7,8,9,10,11,12,13]. Domain Walls are also a key ingredient of Brane world construction [14,15,16,17,18,19]. More recently, in four dimensions, these solitons have been used as a laboratory for the comprehension of mirror symmetry in flux/generalized geometry compactifications [20,21,22] and to explore transitions between the different cosmological vacua of the Landscape [23].…”