Chiral global embedding of fibre inflation models

Abstract

Abstract:We construct explicit examples of fibre inflation models which are globally embedded in type IIB orientifolds with chiral matter on D7-branes and full closed string moduli stabilisation. The minimal setup involves a Calabi-Yau threefold with h 1,1 = 4 Kähler moduli which features multiple K3 fibrations and a del Pezzo divisor supporting nonperturbative effects. We perform a consistent choice of orientifold involution, brane setup and gauge fluxes which leads to chiral matter and a moduli-dependent Fayet-Iliopoulos term. After D-term stabilisation, the number of Kähler moduli is effectively reduced to 3 and the internal volume reduces to the one of fibre inflation models. The inflationary potential is generated by suitable string loop corrections in combination with higher derivative effects. We analyse the inflationary dynamics both in the single-field approximation and by numerically deriving the full multi-field evolution in detail. Interestingly, we find that the Kähler cone conditions set strong constraints on the allowed inflaton field range.

PBH dark matter from axion inflation

“…(3.27) and we also show some plots that ensure the validity of the approximations performed during this models that do not employ axions [136][137][138]. For such inflationary models explicit string theory embeddings have been built, including a controlled moduli stabilization procedure and the presence of a chiral visible sector [139,140]. 44 In this case the gauge bosons receive string scale masses.…”

De Sitter vs Quintessence in String Theory

“…Explicit global models : A fully working 4D string model, should not lead just to a dS vacuum but it should also include SM‐like chiral matter, an inflationary sector and a concrete embedding in globally consistent Calabi‐Yau compactifications with an explicit choice of the orientifold involution, the brane setup, background and gauge fluxes. A lot of progress in this direction has been made recently within the type IIB framework 10.…”

“…Sources of open string moduli fixing : Most of the dS constructions available in the literature just focus on the stabilisation of the closed string moduli but a full working model should include the stabilisation of the open string moduli as well. For a concrete global model with full closed and open string moduli stabilisation see []. In type IIB constructions with D3 and D7 branes most of the open string moduli get fixed by background fluxes.…”

“…Above all, because of the difficulty to solve the minimisation equations in the presence of a large number of complex structure and open string moduli. A lot of progress has been made in this direction (in particular models with an effective small number of complex structure moduli) but a globally consistent model with full moduli stabilisation in a controlled dS vacuum has still to be achieved. However given the existence of a very large number of flux configurations it would be very surprising if there is no solution to these equations. 6.…”

“…Hence it does not make that much sense to obtain dS vacua which cannot realise these other crucial phenomenological features. In the past few years there has been substantial progress in building global models with dS, chiral matter and inflation but a fully working model which can allow for both a realistic cosmology and particle physics is still missing. 7. F‐theory moduli stabilisation : Type IIB models are the weak coupling limit of more general F‐theory constructions.…”