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In recent years, inflationary models have been studied from different perspectives using different conditions. Now, in this paper, we want to investigate the inverse monomial Inflation (IMI) on the brane. We limit our results to the potentials of the form M 4+σ/ϕσ, where M and σ are constants. We calculate some cosmological parameters and then we investigate the satisfaction of the model with some conjectures of the swampland program. We will check the model’s compatibility with the refined dS swampland conjecture (RDSSC), further refining the de Sitter swampland conjecture (FRSDC), scalar weak gravity (SWGC), and strong scalar weak gravity conjecture (SSWGC). Despite the incompatibility with (DSSC), We find a specific region of compatibility with other ones which means it satisfied the (FRDSSC) for example with a = 0.982873, b = 0.017127, and q = 2.2. Also, the model is compatible with the (SWGC) with the (ϕ ≤ σ + 2) condition and consistent with the (SSWGC) with the ϕ ≤ √(σ + 2)(σ + 1) condition. Since, IMI on the brane could satisfy some swampland conjecture simultaneously, it has the potential to be a “real” inflation model of the universe. [ABSTRACT FROM AUTHOR]

In this paper, we investigate hypergeometric stringy corrections in the swampland program for rescaled gravity. Precisely, we study inflationary models from Gauss–Bonnet hypergeometric scalar couplings via the falsification scenario. We first derive generalized exponential potentials from such hypergeometric behaviors. Then, we examine certain selected scalar potentials by computing the relevant cosmological quantities using the slow-roll mechanism. Choosing specific points in the corresponding moduli space, we provide viable findings corroborated by Planck observational data and checked by the swampland criteria. [ABSTRACT FROM AUTHOR]

In this work, we discuss the de Sitter swampland conjectures in the context of the generalized Chaplygin-inspired inflationary model. We demonstrate that these conjectures can be satisfied, but only in the region of the parameter space far away from the General Relativity limit. The cosmic microwave background data had already been found to restrict the allowed inflationary potentials of this model. Our results impose a further limitation on the possible potentials. [ABSTRACT FROM AUTHOR]

A theory of nonassociative geometric flows is formulated as an extension of a string‐inspired model of nonassociative gravity determined by star product. The nonassociative Ricci tensor and curvature scalar defined by (non) symmetric metric structures and generalized (non) linear connections are used for defining nonassociative versions of Grigori Perelman F‐ and W‐functionals for Ricci flows and computing associated thermodynamic variables. The anholonomic frame and connection deformation method, AFCDM, which allows us to construct exact and parametric solutions describing nonassociative geometric flow evolution scenarios and modified Ricci soliton configurations with quasi‐stationary generic off‐diagonal metrics are developed and applied. There are provided explicit examples of solutions modeling geometric and statistical thermodynamic evolution on a temperature‐like parameter of modified black hole configurations encoding nonassociative star‐product and R‐flux deformation data. Further perspectives of the paper are motivated by nonassociative off‐diagonal geometric flow extensions of the swampland program, related conjectures and claims on geometric and physical properties of new classes of quasi‐stationary Ricci flow and black hole solutions. [ABSTRACT FROM AUTHOR]

The compatibility between the de Sitter Swampland conjecture and Hořava–Lifshitz F (R ¯) theories with a flat FLRW metric is studied. We first study the standard f (R) theories and show that the only way in which the dS conjecture can be made independent of R is by considering a power law of the form f (R) ∼ R γ . The conjecture and the consistency of the theory puts restrictions on γ to be greater but close to one. For F (R ¯) theories described by its two parameters λ and μ , we use the equations of motion to construct the function starting with an ansatz for the scale factor in the Jordan frame of the power law form. By performing a conformal transformation on the three metric to the Einstein frame, we can obtain an action of gravity plus a scalar field by relating the parameters of the theory. The non-projectable and projectable cases are studied and the differences are outlined. The obtained F (R ¯) function consists of terms of the form R ¯ γ with the possibility of having negative power terms. The dS conjecture leads to inequalities for the λ parameter; in both versions, it becomes restricted to be greater but close to 1 / 3 . We can also study the general case in which μ and λ are considered as independent. The obtained F function has the same form as before. The consistency of the theory and the dS conjecture lead to a set of inequalities on both parameters that are studied numerically. In all cases, λ is restricted by μ around 1 / 3 , and we obtain λ → 1 / 3 if μ → 0 . We consider the f (R) limit μ , λ → 1 and we obtain consistent results. Finally, we study the case of a constant Hubble parameter. The dS conjecture can be fulfilled by restricting the parameters of the theory; however, the constraint makes this compatibility exclusive to these kinds of theories. [ABSTRACT FROM AUTHOR]

This paper reviews the theoretical and phenomenological implications of the swampland conjectures from the perspective of inflationary cosmology, focusing on warm inflation. We demonstrate how the swampland conjectures appear to favor the strong dissipative regime, giving warm inflation a competitive edge over standard inflation. Additionally, we ponder the possible deeper implications of dissipation for constructing successful inflation models from string theory. [ABSTRACT FROM AUTHOR]

We explore the swampland conjectures of quintessence and tachyon scalar field models in f (T) and Einstein gravities, respectively. In f (T) gravity, we consider cold and warm (by assuming generalized dissipative coefficient) inflationary scenarios and develop constraints on de-Sitter conjectures through Bekenstein entropy relation. In usual inflation, the de-Sitter conjecture constraint becomes constant (in terms of models constant parameters) which can be easily analyzed for its validity (i.e., | V ′ | V ≤ O (1)). However, in warm inflation, we analyze the de-Sitter conjecture constraint through τ ′ V τ V ′ , i.e., if τ ′ V τ V ′ < 1 then | V ′ | V ≤ O (1) and hence we can obtain the required result. For evaluating this condition, we choose three well-known potentials such as monomial chaotic, hilltop and generalized exponential. It is observed that the condition τ ′ V τ V ′ < 1 satisfied for all three potentials in both regimes of dissipative coefficient for specific choice of constants. We also obtain satisfactory results of de-Sitter conjecture for tachyon and polytropic (with quintessence scalar field) in general relativity. We investigate the consistency of assumed potentials through inflationary parameters n s and r comparing with Planck's observational data 2018 and found them compatible with the recent observations. [ABSTRACT FROM AUTHOR]

Swampland conjectures have attracted quite some interest in the cosmological community. They have been shown to have wide ranging implications, like constraints on inflationary models, primordial black holes, dark energy to name a few. Particularly, their implications on single-field inflationary models in general relativity-based cosmology have gathered huge attention. Swampland conjectures in their usual form have been shown to be incompatible with these kinds of single-field models, or have been shown to induce severe fine tuning in these inflationary models for them to be consistent with the conjectures. In this work, we show that a large class of single-field inflationary models can in fact bypass the problems faced by inflationary paradigms in GR-Based cosmology. We use the exact solution approach to inflation for the same purpose and show how string theoretic motivations of the swampland conjectures can be in perfect symphony with various single-field inflationary models in nonstandard cosmological scenarios. [ABSTRACT FROM AUTHOR]

In this paper, we study the inflationary scenario in the realm of k-essence model and swampland conjectures. Taking into account three models of Chaplygin gas, such as generalized, modified, and generalized cosmic Chaplygin gas models, we discuss the equation of state (EoS) parameter ω , slow roll parameters (ϵ (ϕ) , η (ϕ)) , curvature perturbation (P s) , tensor to scalar ratio (r) , and scalar spectral index (n s) . As regards the k-essence model, the coupling function as a function of scalar field L (ϕ) is used. We investigate the swampland conjecture and then find the value of ζ (ϕ) , i.e., bound of second conjecture for these three models by unifying swampland conjecture and k-essence. We plot the EoS parameter ω , inflationary parameters plane r − n s and bound of swampland conjecture ζ (ϕ) − ϕ , which determine that the values of ω < − 1 for each model, r, are r < 0.0094 , r ≤ 0.0065 , r ≤ 0.0067 , and ranges for n s are [ 0.934 , 0.999 ] , [ 0.9 , 0.999 ] , [ 0.9 , 0.992 ] for generalized, modified, and generalized cosmic Chaplygin gas models, respectively, and compare their compatibility with the Planck data from 2018. Furthermore, we determine the bound for swampland conjecture as ζ (ϕ) ≤ 0.992 , ζ (ϕ) ≤ 0.964 , ζ (ϕ) ≤ 0.964 for generalized, modified and generalized cosmic Chaplygin gas models, respectively. [ABSTRACT FROM AUTHOR]

This paper investigates the inflationary phase of the FRW universe within the context of generalized Chaplygin gas. We explore modified cosmological scenarios incorporating two entropy corrections, namely Tsallis and Barrow. These proposed entropies lead to modifications in the Friedmann equations. By incorporating the generalized Chaplygin gas into these equations, we determine various parameters including the slow roll parameters, number of e-folds, curvature perturbation, tensor-to-scalar ratio, and spectral index. We observe variations in the values of the tensor-to-scalar ratio r and the scalar spectral index n s with respect to the Tsallis and Barrow parameters. Additionally, we plot the r − n s plane. For the Tsallis entropy, we obtain r ≤ 0. 012 , r ≤ 0. 027 , and r ≤ 0. 008 , with n s lying between (0. 961 , 0. 964) , (0. 957 , 0. 966) , and (0. 956 , 0. 964) , respectively. In Barrow cosmology, we find r ≤ 0. 0037 , r ≤ 0. 12 , and r ≤ 0. 010 , while n s falls within (0. 92 , 0. 97) , (0. 855 , 0. 995) , and (0. 960 , 0. 966) for the chaotic, SFI, and exponential potentials, respectively. These graphical analyses demonstrate the compatibility of our models with the latest Planck data. Moreover, by considering these entropy corrections, we determine the bounds of the Swampland de Sitter conjecture for generalized Chaplygin gas. In all cases, this bound remains less than unity, satisfying the required condition for the Swampland de Sitter conjecture. [ABSTRACT FROM AUTHOR]

Swampland Conjectures have attracted quite some interest in the Cosmological Community. They have been shown to have wide ranging implications, like constraints on inflationary models, primordial black holes, etc. to name a few. A particularly revealing insight on dark energy also shows that one can have the dark energy equation-of-state for a quintessence scenario to be significantly different than − 1 after one takes into account the refined dS conjecture. Another interesting issue with the swampland conjectures is that they have been shown to be incompatible with single field inflationary models in GR-based cosmology. In our previous work, we have, however, shown that single field inflationary models are quite compatible with swampland conjectures in their usual string theoretic form in a large class of modified cosmological scenarios. Building on that work, we now show that in modified cosmological scenarios where the early universe expansion was driven by single field inflation, one can have the dark energy equation of state to be significantly different from − 1 even if we just take into account the original dS conjecture, let alone the refined form of that. We thereby show that one does not need to apply a step function approach towards inflation in order to have an observable distinction between constant and non-constant dark energy models in the context of the swampland conjectures. [ABSTRACT FROM AUTHOR]

We investigate the consequences of combining swampland conjectures with the requirement of asymptotic safety. To this end, we explore the infrared regime of asymptotically safe gravity in the quadratic one-loop approximation, and we identify the hypersurface spanned by the endpoints of asymptotically safe renormalization group trajectories. These comprise the allowed values of higher-derivative couplings, as well as standard logarithmic form factors. We determine the intersection of this hypersurface with the regions of parameter space allowed by the weak-gravity conjecture, the swampland de Sitter conjecture, and the trans-Planckian censorship conjecture. The latter two depend on some order-one constants, for generic values of which we show that the overlap region is a proper subspace of the asymptotically safe hypersurface. Moreover, the latter lies inside the region allowed by the weak gravity conjecture assuming electromagnetic duality. Our results suggest a non-trivial interplay between the consistency conditions stemming from ultraviolet completeness of the renormalization group flow, black hole physics, and cosmology. [ABSTRACT FROM AUTHOR]

On the basis of the idea that gravity defines a universal UV‐completion and using a form of UV/IR correspondence we revisit some Swampland conjectures, in particular de Sitter and infinite distance conjectures, from the point of view of renormalization group energy flow. The rol and limitations of non perturbative instanton effects to define a metastable cosmological constant are briefly discussed in this context. On the basis of the idea that gravity defines a universal UV‐completion and using a form of UV/IR correspondence some Swampland conjectures are revisited, in particular de Sitter and infinite distance conjectures, from the point of view of renormalization group energy flow. The role and limitations of non perturbative instanton effects to define a metastable cosmological constant are briefly discussed in this context. [ABSTRACT FROM AUTHOR]

In this short note, we pointed out that Warm inflationary scenario remains to be favoured over its cold counterpart by the recently proposed conjectures, which aim to overrule de Sitter like constructions in String Landscapes. On the other hand, the canonical cold (single-field slow-roll) inflationary models, which were in tension with the previously proposed de Sitter conjecture, have now become even more unlikely to realise in String Landscapes as these scenarios fail to cope up with both the conjectures, de Sitter and trans-Planckian censorship, at one go. [ABSTRACT FROM AUTHOR]