Tetra-quadric CY Threefold and Assisted Fibre Inflation

George K. Leontaris; Pramod Shukla; Swagata Bhattacharyya

REVIEW 4 major objections 5 minor 81 references

Tetra-quadric CY Threefold and Assisted Fibre Inflation

T0 review · 4 major / 5 minor · reviewed 2026-08-14 · deepseek-v4-flash

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Pith's one-line read Three Kähler moduli of a tetra-quadric Calabi-Yau orientifold can collectively drive fibre inflation, sharing a 5.7 M_p inflaton shift with each field moving only about 2.2 M_p.

desk verdict Real three-field assisted inflation on a concrete CY, but the mechanism rests on winding-loop corrections the authors admit the standard prescription would exclude. read the letter →

arxiv 2608.10082 v1 pith:PWV2JPRT submitted 2026-08-10 hep-th

Swagata Bhattacharyya , George K. Leontaris , Pramod Shukla This is my paper · ORCID

classification hep-th MSC 83E3083F05 PACS 11.25.-w98.80.Cq

keywords assistedinflationfibreperturbativelargevolumescenarioKählermodulistabilisationtetra-quadricCalabi-YauthreefoldtypeIIBorientifoldstring-loopcorrectionstrans-Planckianfieldexcursion

verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper aims to establish that assisted fibre inflation works in a concrete global string model: the orientifold of the tetra-quadric Calabi-Yau threefold, whose four Kähler moduli carry an $S_4$ exchange symmetry. In the perturbative large volume scenario, the overall volume modulus is stabilized first, and the three remaining Kähler moduli collectively drive inflation through sub-leading string-loop and higher-derivative corrections. The paper's central quantitative result is that an effective inflaton displacement of about $5.7\,M_p$ can be shared by three fields that each move only about $2.2\,M_p$, while the scalar power spectrum, spectral index, running, and tensor-to-scalar ratio stay inside the Planck and ACT bounds. The reason this matters is that fibre inflation normally requires a super-Planckian single-field excursion; the assisted construction gets the same cosmological outcome without pushing any individual modulus to a super-Planckian value or toward the boundary of the Kähler cone, softening concerns about the validity of the effective field theory and swampland constraints.

What carries the argument

The machinery is the perturbative large volume scenario (pLVS): the overall volume modulus $V$ is fixed at an exponentially large minimum by the BBHL $\alpha'^3$ correction plus log-loop string corrections, leaving three flat Kähler directions. Those directions are lifted by winding-type string-loop terms $V_W = -(\kappa |W_0|^2/V^3) \sum_\alpha C_W^\alpha / t_\alpha^{\cap}$, written in terms of the two-cycle volumes $t_\alpha^{\cap}$ of D7/O7 intersection curves, and by higher-derivative $F^4$ terms $V_{F_4} \propto -\lambda \kappa^2 |W_0|^4/(g_s^{3/2} V^4) \sum_\alpha \Pi_\alpha t_\alpha$. The $S_4$ symmetry of the tetra-quadric volume form $V = 2(t_1 t_2 t_3 + t_1 t_2 t_4 + t_1 t_3 t_4 + t_2 t_3 t_4)$ leaves a residual $S_3$ exchange symmetry among $t_2,t_3,t_4$, which makes isotropic minima and a flat inflationary track possible. The field-space metric in the $\{V,t_2,t_3,t_4\}$ basis has off-diagonal components that enter the distance integral $\Delta\Phi = \int \sqrt{2\epsilon_H(N)}\,dN$, which is why the three fields together cover $5.7\,M_p$ while each moves only $2.2\,M_p$.

What would settle it

A direct one-loop string computation of the Kähler-potential corrections for the tetra-quadric orientifold with $\sigma_i: x_i \to -x_i$ would settle the matter: if it gives $C_W^\alpha = 0$ for all $\alpha$, the potential in Eq. (5.1) no longer has the flat track that stabilizes $t_2,t_3,t_4$, and the claimed $\Delta\Phi \approx 5.7\,M_p$ with $\Delta\Phi_a \approx 2.2\,M_p$ would not be produced.

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Extended reading notes

Core claim

On its own terms, the paper claims that the tetra-quadric hypersurface in $P^2 \times P^2 \times P^2 \times P^2$, with $h^{1,1}=4$, all coordinate divisors K3, and intersection polynomial $2(D_1 D_2 D_3 + D_1 D_2 D_4 + D_1 D_3 D_4 + D_2 D_3 D_4)$, admits an orientifold involution $\sigma_i: x_i \to -x_i$ with O7-planes and no O3-planes. With the overall volume $V$ stabilized by BBHL and log-loop corrections at an exponentially large value, the sub-leading winding-type loop corrections together with higher-derivative $F^4$ corrections stabilize $t_2,t_3,t_4$ in an $S_3$-symmetric minimum. Numerically integrating the multi-field equations with $N=54$ e-folds for the benchmark Model B gives $P_s = 2.19\times 10^{-9}$, $n_s = 0.9733$, $\alpha_s = 1.56\times 10^{-4}$, $r = 7.44\times 10^{-3}$, an effective field excursion $\Delta\Phi = 5.71\,M_p$, and individual excursions $\Delta\Phi_a = 2.20\,M_p$ for $a=2,3,4$. The paper interprets the fact that $\Delta\Phi_a$ is smaller than $\Delta\Phi/\sqrt{3} \simeq 3.30\,M_p$ as evidence that the off-diagonal terms in the field-space metric make the assistance more effective than the canonical Pythagorean estimate.

Load-bearing premise

The whole construction depends on assuming that winding-type string-loop corrections of the assumed form $V_W = -(\kappa |W_0|^2/V^3) \sum_\alpha C_W^\alpha / t_\alpha^{\cap}$ appear for the chosen orientifold involutions, even though the usual prescription says none should appear; if they are absent or have a different field dependence, the flat inflationary track disappears.

Editorial extensions

If this is right

Model B reproduces Planck-ACT/DESI-compatible observables, $P_s \approx 2.2\times 10^{-9}$, $n_s \approx 0.973$, $\alpha_s \approx 1.6\times 10^{-4}$, and $r \approx 0.0074$, without invoking any non-perturbative superpotential.
Individual canonical displacements of about $2.2\,M_p$ keep each field below the naive single-field trans-Planckian threshold, so the $5.7\,M_p$ effective shift is obtained without a single modulus crossing a super-Planckian range.
The same perturbative potential fixes all four Kähler moduli simultaneously, so the assisted-inflation mechanism does not rely on exceptional divisors or non-perturbative instantons.
The mass hierarchy $m_a < H < V^{1/4} < m_{3/2} < M_{KK} < M_s < M_p$ is maintained throughout inflation, supporting the decoupling of the heavy overall-volume mode.
Because the assistance beats the $\Delta\Phi/\sqrt{n}$ Pythagorean estimate, the effective excursion in a multi-field model is not the right quantity for judging swampland-distance or EFT control; the individual excursions are.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

A natural next test is to scan other Calabi-Yau orientifolds with $h^{1,1} > 4$ and larger discrete symmetries; if the off-diagonal metric effect grows with the number of moduli, individual excursions could fall well below $2\,M_p$.
The load-bearing assumption that winding-type corrections are present despite the stated absence under the standard prescription could be checked by an explicit one-loop string computation; if the coefficients vanish, the model would need a different sub-leading effect to create the flat track.
The authors' own observation that a KK scale approaches the string scale near the minimum suggests a concrete robustness test: check whether higher-order $\alpha'$ corrections or open-string states modify the potential in the last few e-folds, which would change the predicted $n_s$ and $r$.
The 'better than $\sqrt{n}$' behaviour implies the Pythagorean estimate used in earlier assisted-inflation arguments is not a fundamental bound; a model with larger off-diagonal metric entries might achieve near-equal sharing with even smaller per-field displacements.

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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Desk Editor's Note

read the letter

Short version: the paper does what it says, on its own terms. The tetra-quadric construction is concrete, the three-field assisted mechanism works in the numerics, and the individual-excursion reduction (2.2 vs 5.7 Mp) is a genuine effect of the non-diagonal field-space metric, not just the Pythagorean n^{-1/2} scaling. That is a real step beyond the two-field model in [33]. The authors also put the full potential, benchmark parameters, and consistency checks (mass hierarchy, KK scales) on the table. Credit where due: the topological data are explicit and the calculation is reproducible enough to check.

The soft spot is exactly the one the stress-test note flags. In Sec. 4.3 they state that for the chosen involutions there should be no winding-type contributions under the standard prescription, then include them anyway based on generic arguments in [24,28,57]. These corrections stabilize t2,t3,t4 and generate the flat plateau; without them the model does not inflate. That is not a minor technicality. To the authors' credit they do not hide it, and they cite a recent paper that may offer a BHP-free regime. Still, the benchmark coefficients Cw and ~Cw are free inputs, and the advertised predictions are compatibility demonstrations more than parameter-free derivations. The field-distance estimate also uses the tree-level metric, and the authors themselves note the KK masses approach the string scale near the minimum, so the EFT is not as clean as one would like.

Nothing here is fatal if the goal is to show what assisted inflation could look like in a concrete CY. The paper is transparent about its assumptions, and the numerics are laid out carefully. What it does not do is justify the existence of the winding corrections from the compactification. A referee should press on that point.

This paper deserves a serious referee. I would send it out and ask for a response to the winding-correction objection, and maybe for one-parameter sensitivity of the benchmark choices. It is a reading-group-worthy paper for string cosmologists, and I would cite it as the three-field assisted inflation model if I worked on that topic.

Referee Report

4 major / 5 minor

Summary. The paper constructs a global type IIB orientifold model of assisted fibre inflation on the tetra-quadric Calabi-Yau threefold, which has h^{1,1}=4 and an S_4 permutation symmetry. The overall volume modulus is stabilized in the perturbative large-volume scenario using BBHL alpha'-corrections and log-loop terms, while the remaining three Kähler moduli t_2, t_3, t_4 are claimed to drive assisted fibre inflation through sub-leading winding-type string-loop and F^4 corrections. Two benchmark models are presented, with moduli stabilized numerically and inflationary dynamics evolved in a three-field system; the resulting power spectrum amplitude P_s, spectral index n_s, running alpha_s, and tensor-to-scalar ratio r are compared with Planck and ACT data. The central headline claim is that an effective inflaton shift of about 5.7 M_p can be achieved with individual shifts of only about 2.2 M_p for each of the three inflaton moduli, improving on the naive sqrt(3) Pythagorean estimate.

Significance. If the construction is valid, the paper would be a valuable explicit global embedding of assisted inflation in string theory, showing that multiple Kähler moduli can collectively source the large effective field excursion needed for fibre inflation while keeping each individual field sub-Planckian. The work is technically substantial: it uses concrete Calabi-Yau data, computes the field-space metric and connections, performs four-field moduli stabilization, and gives a full numerical inflationary evolution with mass hierarchy checks. The benchmark observables are in reasonable ranges and the two models illustrate both Planck-compatible and ACT-compatible parameter choices. The main significance, however, is conditional on the presence of the assumed winding-type string-loop corrections, a point that the paper itself flags as not following from the standard prescription for the chosen involutions. The headline assistance effect is therefore an interesting proposal whose microphysical basis remains to be established.

major comments (4)

[§4.3, Eq. (4.15)] The winding-type loop correction V_W = -(κ|W0|^2/V^3) Σ C_W^α / t_α^∩ is the load-bearing ingredient of the model, entering the benchmark potential (5.1), the moduli VEVs (5.6), and the inflationary dynamics of Section 6. Yet the text states explicitly that for the involutions σ_i 'there should be no Winding-type contributions a la prescription of [23,25-27,56]', and the corrections are included only on the basis of generic arguments from [24,28,57]. For a global orientifold model claiming to realize assisted fibre inflation, the presence and moduli dependence of these corrections must be derived or at least explicitly justified for this brane setting; citing generic expectations is not sufficient. If these corrections are absent, the three remaining moduli stay flat, the benchmark minima of Section 5.2 disappear, and the assisted-inflation mechanism does not operate.
[§5.2, Tables 4 and 5] The benchmark models depend on a substantial set of freely chosen parameters: C_w, C̃_w, λ, W_0, g_s, C_up, and the horizon-exit values t_a*. The paper does not demonstrate that these values are realizable by flux choices satisfying D3/D7 tadpole cancellation and flux quantization in the tetra-quadric orientifold. Consequently the agreement with Planck/ACT data is a demonstration of compatibility rather than a prediction. This tuning alone does not invalidate the construction, but it should be stated more carefully in the conclusions, where the results are described as reproducing observational constraints.
[§6.3, Table 5] The headline reduction of individual field excursions is based on the quantities ΔΦ_a computed 'by considering the motion of one modulus while keeping the other two at their respective minima', whereas ΔΦ is computed along the actual multi-field trajectory using Eq. (6.6). These are conceptually different measures: ΔΦ_a is a single-field distance at fixed other fields, not the displacement of that field during the assisted evolution. The paper should clarify whether the individual displacements along the actual trajectory are indeed about 2.2 M_p, or whether that number is only a single-field estimate at fixed companions.
[§6.4 and §7] The authors note that towards the minimum one of the KK scales becomes comparable to the string mass and conclude that the EFT description 'may not be as clean and robust as one would like it to be'. Since the whole point of the construction is to avoid trans-Planckian individual excursions while retaining a controlled EFT, the paper should quantify the degree of control during the last 50 e-folds: for example, give the ratios M_KK/H, M_s/H, and m_3/2/H over the full observable range, and specify where the KK-string crossover occurs relative to the end of inflation. As written, the validity of the supergravity approximation at the relevant scales is asserted rather than demonstrated.

minor comments (5)

[§4.1] The text refers to the 'Kreutzer-Skarke' database; the standard name is Kreuzer-Skarke.
[§3.2, Eq. (3.17)] The notation in the canonical field definitions is inconsistent: the third line mixes φ_3 and ϕ_3, and the second line uses ϕ_3 as well. Please unify the symbol φ vs ϕ throughout the paper.
[§5.1, Eq. (5.6)] The expression for ⟨t_a⟩ drops the e^{K_cs} factor contained in κ = g_s e^{K_cs}/2. If this factor is absorbed into the definition of W_0 or λ, that convention should be stated explicitly, since it affects the numerical benchmark values.
[§6] There is a typo 'symetry' in the sentence introducing the residual symmetry 2↔3↔4.
[Figures 4-9] Several figure axes are difficult to interpret: for example, Fig. 4 plots 'V(N)·10^10' but the vertical axis label reads '1.6 1.8 2.0 2.2 2.4' without units, and Fig. 9 has an axis labeled 'αs' with values 0.00-0.04, which appears inconsistent with the running values reported in Table 4. Please add clear axis labels and legends.

Circularity Check

0 steps flagged · score 1.0 of 10

No circular derivation: the assisted-shift and cosmological numbers are computed from an explicit potential, not restated inputs; the acknowledged winding-loop assumption is an unverified premise, not a circular step.

full rationale

The paper's central derivation chain is self-contained. The benchmark scalar potential in Eq. (5.1) is an explicit function of the Kähler moduli, the moduli VEVs and Hessian in Eqs. (5.6)-(5.7) follow from minimization of that potential, and the inflationary trajectories are obtained by numerically integrating the multi-field equations (6.1) with the field-space metric and connections given in Appendix A. The headline numbers in Table 5 are computed from the path-length integral ΔΦ = ∫ sqrt(2ϵ_H) dN in Eq. (6.6) and from the individual-distance estimate defined in Section 6.3; they are not restatements of the input parameters C_W, λ, W0, or Cup. The cosmological observables in Table 4 are evaluated from the standard formulas in Eq. (2.26) after the benchmark parameters are selected, and the paper describes them as 'reproduces' rather than as independent forecasts; that is a fitting/model-compatibility caveat, not a circular reduction. The main physical weakness is the winding-type loop potential in Eq. (4.15): Section 4.3 explicitly says that for the chosen involutions 'there should be no Winding-type contributions a la prescription of [23,25-27,56]' and that the terms are included only on generic arguments. This is a load-bearing assumption and a correctness risk, but it is an input assumption, not a claim that reduces to its own output. The heavy reliance on prior work by the same authors, especially [33] and [71], supplies the pLVS and assisted-fibre-inflation framework, but the four-field computation performed here is explicit and does not reduce to those citations. Overall, no step in the derivation is circular by construction.

Assumptions & free parameters 8 free parameters · 7 assumptions · 0 invented entities

The central dynamics depend on several model-dependent parameters and on assumed forms of sub-leading perturbative corrections. The most fragile input is the winding-type loop correction, whose standard prescription predicts absence for the chosen involution; the authors proceed on a generic expectation. The field-space distance is computed with the tree-level metric, and the benchmark parameters are tuned to match cosmological observables.

free parameters (8)

string coupling g_s = 0.24 (Model A), 0.29 (Model B)
Chosen to control the pLVS volume VEV and the loop corrections; tuned together with other parameters so that P_s ≈ 2.1e-9 and n_s match data.
flux superpotential W0 = 2.3 (Model A), 4.0 (Model B)
Sets the overall scale of the potential; selected by hand in the benchmark models and not derived from an explicit flux choice.
winding-loop coefficient C_w = 0.13 (Model A), 0.027 (Model B)
Controls the VEV of the three inflaton moduli (Eq. 5.6) and the plateau shape; tuned to get N≈54 e-folds and the right n_s.
winding-loop coefficient tilde C_w = -0.001 (Model A), -0.0043 (Model B)
Appears in the steepening part V_W^(ii); its sign and size are adjusted to produce a sufficiently long flat track.
F4 coefficient lambda = -0.001 (Model A), -0.0001 (Model B)
Higher-derivative coupling; chosen negative to stabilize the AdS minimum and to balance the negative winding contribution during inflation.
log-loop parameters eta0 and sigma0 = eta0=8, sigma0=-6 (both models)
Set the pLVS potential and the exponentially large volume VEV; values chosen in the natural range used in prior work.
uplift coefficient C_up = 0.481727 (Model A), 1.99996 (Model B)
Adjusted to lift the AdS minimum to a near-Minkowski or de Sitter vacuum after the other parameters are fixed.
horizon-exit field values t_a* (a=2,3,4) = 9.15 (Model A), 12.7 (Model B)
Initial conditions for the numerical evolution; chosen so that N* = 3-4 e-folds before the end gives the target observables.

assumptions (7)

standard math The F-term scalar potential V = e^K (K^{AB} D_A W D_B W - 3|W|^2) and the no-scale structure hold at leading order.
Eqs. (2.1)-(2.2); standard N=1 supergravity, used to derive all potential pieces.
standard math The multi-field inflaton dynamics are governed by the second-order equations with non-trivial field-space metric and Hubble friction.
Eqs. (2.17)-(2.26); standard cosmology used for the numerics.
domain assumption The perturbative LVS potential V_pLVS = C1/V^3 (xi + 2 eta ln V - 8 eta + 2 sigma) fixes the overall volume.
Eq. (4.13); taken from the authors' earlier pLVS papers without re-derivation.
ad hoc to paper Winding-type loop corrections contribute V_W = -(kappa |W0|^2/V^3) sum C_W^alpha / t_alpha^cap, although the standard brane-setting prescription for the chosen involution predicts no such corrections.
Section 4.3; the authors include them on generic arguments from [24,28,57]. This is the load-bearing assumption for the inflationary plateau.
domain assumption F4 higher-derivative corrections take the form V_F4 = -(lambda kappa^2 |W0|^4)/(g_s^{3/2} V^4) sum Pi_alpha t_alpha with Pi_alpha = 24 for all K3 divisors.
Eq. (4.17); from [29], with model-dependent lambda treated as free.
domain assumption The tree-level Kähler potential K = -2 ln V is used for the field-space metric and connections; sub-leading corrections to the metric are neglected when computing distances.
Appendix A, Eqs. (A.1)-(A.6); affects the reported effective and individual field excursions.
domain assumption The complex structure moduli and axio-dilaton are flux-stabilized with W0 as an input; an explicit flux realization of W0=2.3 or 4.0 is assumed to exist.
Section 2.1; standard in pLVS model building, but no explicit flux construction is given.

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Cite this review

Pith. "Pith review of Tetra-quadric CY Threefold and Assisted Fibre Inflation." pith.science (2026). https://pith.science/paper/PWV2JPRT

@misc{pith2026260810082,
  author       = {Pith},
  title        = {Pith review of: Tetra-quadric CY Threefold and Assisted Fibre Inflation},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/PWV2JPRT}},
  note         = {Machine review of arXiv:2608.10082}
}

abstract

In the context of type IIB superstring compactification, we demonstrate the assisted fibre inflation proposal for a four-field model realized using the orientifold of a tetra-quadric Calabi-Yau (CY) threefold. This CY threefold has an underlying permutation symmetry $S_4$ and belongs to both the list of CY threefolds, namely the Kreuzer-Skarke (KS) database as well as the Complete Intersection Calabi-Yau (CICY) database. After fixing the overall volume modulus of the CY threefold using the framework of perturbative large volume scenario, there are three K\"ahler moduli which remain flat and assist in driving fibre inflation via sub-leading corrections. In a particular benchmark model, we show that the effective inflaton shift of around $5.7$ M$_p$, as needed for driving fibre inflation, can be successfully shared by three inflaton moduli which need to be individually shifted by nearly $2.2$ M$_p$ only ! The main motivation for the work is to show that the effective large field excursions of the inflaton field is possible without the need of pushing the individual volume moduli towards a large super-Planckian excursion or close to the boundary of the K\"ahler cone which may create various subsequent challenges for the effective field theory and supergravity approximations, especially in Swiss-Cheese based models of fibre inflation.

Figures

Figures reproduced from arXiv: 2608.10082 by the authors.

**Figure 1.** Scalar potential (V · 1010) plotted for a single modulus at a time while assuming the other moduli to be fixed at their respective minimum. Here Φ1 is the overall volume V while Φa = {t 2 , t3 , t4} for a = {1, 2, 3} due to the underlying exchange symmetry, namely 2 ↔ 3 ↔ 4. 0.2 0.4 0.6 0.8 1.0 Φa 0.1 0.2 0.3 0.4 0.5 0.6 V(Φa) -2 2 4 6 8 Log[Φa] 1 2 3 4 V(Φa) [PITH_FULL_IMAGE:figures/full_fig_p020_1.png] view at source ↗

**Figure 2.** Scalar potential (V · 1010) plotted for the individual inflaton moduli Φa = {t 2 , t3 , t4} while assuming the overall volume V to be fixed at its respective minimum. The right side figure manifestly shows the typical single-field flat track of the fibre inflation model. 20 [PITH_FULL_IMAGE:figures/full_fig_p020_2.png] view at source ↗

**Figure 3.** Two dimensional plot of the scalar potential (V · 1010) while assuming the {t 3 , t4} moduli to be fixed at their respective minimum. The second figure plotted for (ln(V · 1010)) clearly demonstrates the minimum as compared to the first one. 6 Assisted Fibre Inflation In this section, we present the numerical analysis leading to a fibre inflation model assisted by three alike moduli, namely Φa = {t 2 , t3 , t4}, sup… view at source ↗

Figures from the paper (8 more)

**Figure 4.** Figure 4: Evolution of the scalar potential V (N) · 1010 plotted for the number of efoldings 10 20 30 40 50 N 2 4 6 8 10 12 ϕa(N) 52 53 54 55 N 0.4 0.6 0.8 1.0 1.2 ϕa(N) [PITH_FULL_IMAGE:figures/full_fig_p022_4.png]

**Figure 5.** Figure 5: Evolution of Φa (N) for a = {2, 3, 4} 22 [PITH_FULL_IMAGE:figures/full_fig_p022_5.png]

**Figure 6.** Figure 6: Evolution of slow-roll parameter ϵH(N) 10 20 30 40 50 N 0.5 1.0 1.5 2.0 ηH 51 52 53 N 0.5 1.0 1.5 2.0 ηH [PITH_FULL_IMAGE:figures/full_fig_p023_6.png]

**Figure 7.** Figure 7: Evolution of slow-roll parameter ηH(N) 2 4 6 8 10 N 2.0×10-9 2.2×10-9 2.4×10-9 Ps 2 4 6 8 10 N 0.70 0.75 0.80 0.85 0.90 0.95 ns [PITH_FULL_IMAGE:figures/full_fig_p023_7.png]

**Figure 8.** Figure 8: Evolution of Ps(N) · 109 and ns(N) with dashed lines for Ps = 2.1 · 10−9 and ns = 0.975. 6.3 Inflaton field range and assisted nature of inflation Given the moduli space metric Gab for the fields Φa , the distance is given as ds2 = Gab dΦ a dΦ b , (6.4) and subsequentl…

**Figure 9.** Figure 9: Evolution of αs(N) and r(N) using definitions in (2.27) and ϕ ≡ ϕ(N). For our purpose, given that we have already solved the inflationary trajectories in terms of the efolds N, one can take it as a good parameter to characterize the effective inflationary curve in the …

**Figure 10.** Figure 10: Evolution of scalar potential (V · 1010) and its pieces showing that the effective inflaton potential receives negative contributions from the Winding-type corrections which is compensated by the F4 corrections such that the total potential remains flat enough to driv…

**Figure 11.** Figure 11: Evolution of various mass scales during inflationary dynamics The evolution of various scales as presented in figure 11 shows that mass-hierarchy (6.11) is respected throughout the inflationary regime, i.e. till ϵH ≤ 1 corresponding to N ≃ 54.08. However, we also obse…

Discussion (0). Continue with ORCID to comment.

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