Recently a swampland criterion has been proposed that rules out de Sitter vacua in string theory. Such should hold at all points the field space and especially where system is on-shell. However there not any attempt to examine against explicit equations of motion. In this paper we study four-dimensional quasi-de solutions using dimensionally reduced M-theory. While on one hand classical sources could allow for with isometries are ruled out, quantum corrections, other hand, found provided...

The late-time behavior of our universe is one accelerated expansion, or that a de Sitter space, and therefore motivates us to look for time-dependent backgrounds. Finding such backgrounds in string theory has always been challenging problem. An even harder problem find allow positive dark energies. As first step handle scenarios, we study background type IIB theory, with four-dimensional isometries, by uplifting it M-theory then realizing as coherent, squeezed-coherent, state over an...

We evaluate the backreaction of O6-planes in scale-separated $\text{AdS}_3$ flux vacua massive Type IIA. Using appropriate scaling we show that corrections to various background fields and moduli are controlled subleading when going from smeared localized sources. Similarly, scalar potential parametrically small scale-separation limit, assuming always near-O6-plane singularities will find a resolution within string theory, even presence Romans mass. Our analysis is based on equations motion...

It has been recently argued that inserting a probe anti-D3-brane in flux background breaks supersymmetry spontaneously instead of explicitly, as previously thought. In this paper we argue such spontaneous breaking persists even when the is kept curved with an internal space doesn't have to be Calabi-Yau manifold. To show take specific generated by fractional three-branes and fluxes on non-Kahler resolved conifold where appears directly from certain world-volume fermions becoming massive....

We prove that charged gravitini cannot have parametrically small or vanishing Lagrangian mass in de Sitter vacua of extended supergravity while respecting the magnetic weak gravity conjecture. This places large classes solutions gauged swampland, including all known stable N=2 theory. illustrate this result by analyzing a variety critical points matter-coupled also include new solutions. Our results provide concrete evidence (quasi) with light should belong to which strongly resonates...

We derive the 3D N = 1 superpotential for closed string sector of type IIB supergravity on toroidal O5 orientifolds with co-calibrated G2 structure and RR background flux. find that such compactifications can provide full moduli stabilization supersymmetric $$\hbox {AdS}_3$$ vacua, once we include brane-supersymmetry-breaking also indication existence classical de Sitter solutions. The latter however are rather difficult to reconcile "shape" flux quantization. discuss possibility achieving...

We investigate the possible appearance of composite states goldstino in models with four-dimensional non-linear supersymmetry and we provide a description their dynamics terms K\"ahler potential superpotential. Our analysis shows that critical point corresponding to Volkov-Akulov model is unstable. Similarly, find uplifted stable de Sitter KKLT shifted acquires tachyonic instability. findings indicate existence potentially dangerous instability shared by all anti-brane uplifts.

We study the possibility of realizing scale-separated type IIB Anti-de Sitter and de compactifications within a controlled effective field theory regime defined by low-energy large (but scale-separated) compactification volume. The approach we use views theories as truncations full quantum equations motion expanded in trans-series around this asymptotic regime. By studying scalings all possible perturbative non-perturbative corrections identify effects that have right scaling to allow for...

We argue that, in the presence of time-dependent fluxes and quantum corrections, four-dimensional de Sitter solutions should appear type IIB string landscape not swampland. Our construction considers generic choices local non-local terms satisfies no-go swampland criteria, latter being recently upgraded using trans-Planckian cosmic censorship. Interestingly, both time-independent Newton constant moduli stabilization may be achieved such backgrounds even internal spaces. However, once...

We study the interplay between extrema of axion potentials, Kahler moduli stabilization and swampland criteria. argue that moving away from minima non-perturbatively generated potentials can lead to a runaway behavior govern couplings in effective field theory. The proper inclusion these degrees freedom resolves conflict periodic gradient de Sitter criterion, without need invoke refined criterion. investigate possibility including this direction as model quintessence satisfies Using single...

Scale-separated AdS compactifications of string theory can be constructed at the two-derivative supergravity level in presence smeared orientifold planes. The unsmearing corrections are known to leading order large volume, weak coupling limit. However, first-order perturbative approximations non-linear problems often produce spurious solutions, which only weeded out by additional consistency conditions imposed higher orders. In this work, we revisit procedure and present obtained from second...

The known supergravity solution for wrapped D5-branes on the two-cycle of a Kähler resolved conifold is in general ISD but not supersymmetric, with supersymmetry being broken by presence (1, 2) fluxes. However if we allow non-Kähler metric conifold, can easily be restored. vanishing fluxes here corresponds to, under certain conformal rescalings metric, torsion class constraints. We construct explicit metrics satisfying All this also studied from M-theory, where and branes become...

Abstract The dynamics of certain string configurations in a class fivebrane supertube backgrounds is studied. In the decoupling limit fivebranes, these solutions are known to admit an exact description worldsheet theory and propagation integrable. For asymptotically flat solutions, by using analytic tools classical Hamiltonian systems, non‐integrability motion proved. This suggests that circular geometries exhibit regime chaotic behavior.

The ultraviolet completion of a large $N$ QCD model requires introducing new degrees freedom at certain scale so that the UV behavior may become asymptotically conformal with no Landau poles and divergences Wilson loops. These are represented by antibranes arranged on blown-up sphere warped resolved conifold in way they separated from other set branes control IR theory. This separation creates instability Further complications arise curvature ambient space. We show that, despite these...

We present two types of obstacles for constructing de Sitter space in supersymmetric theories that appear as effective quantum gravity. The first obstacle concerns critical points extended supergravity with charged massless gravitini. show all such have a Hubble scale the same order or above UV cutoff dictated by magnetic Weak Gravity Conjecture. second dynamics goldstino models non-linearly realized supersymmetry, string involving anti-branes. show, using an exact renormalization group...

A bstract Scale-separated AdS compactifications of string theory can be constructed at the two-derivative supergravity level in presence smeared orientifold planes. The unsmearing corrections are known to leading order large volume, weak coupling limit. However, first-order perturbative approximations non-linear problems often produce spurious solutions, which only weeded out by additional consistency conditions imposed higher orders. In this work, we revisit procedure and present obtained...

Gravity duals for a class of UV complete minimally supersymmetric nonconformal gauge theories require deformed conifolds with fluxes. However these manifolds do not allow the standard Kähler or conformally metrics on them, instead are fully non-Kähler. We take generic such configuration non-Kähler conifold fluxes and ask what constraints supersymmetry impose in baryonic branch. study conditions show that correct choices vielbeins complex structure all equations may be consistently solved....

In this review we argue that four-dimensional effective field theory descriptions with de Sitter isometries are allowed in the presence of time-dependent internal degrees freedom type IIB string landscape. Both moduli stabilizations and time-independent Newton constants possible such backgrounds. However once time-dependences switched off, there appear no possibilities these backgrounds swampland.

We study the dynamics of certain string configurations in a class fivebrane supertube backgrounds. In decoupling limit fivebranes, these solutions are known to admit an exact description worldsheet theory and propagation is integrable. For asymptotically flat solutions, we prove, by using analytic tools classical Hamiltonian systems, non-integrability motion. This suggests that circular geometries exhibit regime chaotic behaviour.

Gravity duals for a class of UV complete minimally supersymmetric non-conformal gauge theories require deformed conifolds with fluxes. However these manifolds do not allow the standard Kahler or conformally metrics on them, instead are fully non-Kahler. We take generic such configuration non-Kahler conifold fluxes and ask what constraints supersymmetry impose in Baryonic branch. study conditions show that correct choices vielbeins complex structure all equations may be consistently solved....

We present two types of obstacles for constructing de Sitter space in supersymmetric theories that appear as effective quantum gravity. The first obstacle concerns critical points extended supergravity with charged massless gravitini. show all such have a Hubble scale the same order or above UV cutoff dictated by magnetic Weak Gravity Conjecture. second dynamics goldstino models non-linearly realized supersymmetry, string involving anti-branes. show, using an exact renormalization group...