Pith. sign in

REVIEW 4 major objections 4 minor 62 references

Observational Restrictions and Slow-Roll D-brane Inflation in the Special $F(\phi,T)$ Gravity

T0 review · 4 major / 4 minor · reviewed 2026-08-06 · deepseek-v4-flash

Pith's one-line read The paper claims that a D-brane inflation model in F(φ,T) modified gravity, with a specific non-minimal coupling and potential, produces scalar spectral index and tensor-to-scalar ratio values that fall inside the Planck 2018 1σ and 2σ…

desk verdict Routine F(φ,T) extension with hand-tuned parameters; algebra errors and an unverified η_V make the quoted ns/r values unreliable. read the letter →

arxiv 2507.23321 v1 pith:2AAECBQH submitted 2025-07-31 gr-qc hep-th

classification gr-qchep-th PACS 04.50.Kd98.80.Cq
keywords D-braneinflationF(phiT)gravitymodifiedslow-rollparametersscalarspectralindextensor-to-scalarratioPlanck2018datareheating
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

This paper tries to establish that the D-brane inflationary model, embedded in the modified gravity $F(\phi,T)$ with a non-minimal coupling $\beta F(\phi)T$, can reproduce the Planck 2018 constraints on the scalar spectral index $n_s$ and the tensor-to-scalar ratio $r$ – in particular, it claims the model 'accurately covers the left-hand side of the Planck data and the D-brane inflation.' The authors choose $F(\phi)=\phi^5/\mu\,(1-m^4/\phi^4)$ and $V(\phi)=V_0(1-m^4/\phi^4)$, compute the slow-roll parameters, $n_s$ and $r$ for 50–60 e-folds, and show that with small negative $\beta$ and suitable $\mu$ the predictions fall inside the Planck 1$\sigma$–2$\sigma$ contours with $r$ between $10^{-6}$ and $10^{-4}$. They also analyze reheating and find temperatures and e-fold durations that respect the big-bang nucleosynthesis bound. If correct, the work extends D-brane inflation into the $F(\phi,T)$ framework and offers a string-motivated route to the low-$r$ region of the Planck data.

What carries the argument

The central object is the non-minimal coupling term $\beta F(\phi)T$ in the action (2.1), where $T=g^{\mu\nu}T_{\mu\nu}$ is the trace of the energy-momentum tensor; with $F(\phi)=\phi^5/\mu\,(1-m^4/\phi^4)$ and $V(\phi)=V_0(1-m^4/\phi^4)$, this coupling reshapes the Friedmann equations and the scalar-field equation of motion (2.12)–(2.15). From those equations the paper builds the slow-roll parameters $\epsilon_V$ and $\eta_V$, then maps them to observables through $n_s\simeq1+2\eta_V-6\epsilon_V$ and $r\simeq16\epsilon_V$, and finally uses the e-fold integral (2.20) to determine the field value at horizon crossing for $N=50$ or $60$. The same modified Friedmann equation drives the reheating calculation, relating the decay rate $\Gamma_\phi$ to the reheating temperature $T_{reh}$ and the number of reheating e-folds $N_{reh}$.

What would settle it

Recompute $n_s$ and $r$ using the directly varied field equation (2.9) in place of (2.15) and check whether the resulting points remain inside the Planck 2018 1$\sigma$–2$\sigma$ contours; until the two routes to the equation of motion are reconciled, the fit is not uniquely determined.

Watch

Extended reading notes

Core claim

The paper's central claim, stated on its own terms, is that the action (2.1), namely Einstein gravity plus $\beta F(\phi)T$ with the D-brane-inspired functions $F(\phi)=\phi^5\mu^{-1}(1-m^4\phi^{-4})$ and $V(\phi)=V_0(1-m^4\phi^{-4})$, yields an inflationary dynamics whose observables $n_s$ and $r$ agree with the Planck 2018 data and specifically populate the left-hand (low-$r$) side of the $(n_s,r)$ plane. The paper derives the slow-roll parameters $\epsilon_V$ and $\eta_V$, the e-fold number $N$, and the resulting observables for $N=50$–$60$, reporting $n_s$ roughly in $0.95$–$0.97$ and $r$ from $10^{-6}$ to about $2\times10^{-4}$, all consistent with the BICEP/Keck 2021 bound $r<0.036$. In the limit $\beta\to0$, these predictions reduce to the standard simplest D-brane inflation in Einstein gravity, and for other parameter choices the same model can also cover the right-hand side of the Planck contours.

Load-bearing premise

The computed $n_s$ and $r$ values rest on equation (2.15) being the correct equation of motion for the scalar field in this action; every numerical comparison with the Planck contours depends on that one dynamical input.

Editorial extensions

If this is right

  • For the parameter sets in Tables 1 and 2 with $N=50$–$60$, the predicted $(n_s,r)$ points lie inside the Planck 2018 1$\sigma$–2$\sigma$ regions, giving a modified-gravity realization of D-brane inflation that is consistent with current CMB data.
  • The predicted tensor-to-scalar ratio is very small, $r\sim10^{-6}$–$10^{-4}$, far below the BICEP/Keck 2021 bound $r<0.036$, so future $B$-mode searches could test the model.
  • At $\beta=0$ the model reduces continuously to the simplest D-brane inflation in Einstein gravity, so the modified gravity is an extension of the known Einstein-gravity result.
  • The reheating analysis gives $T_{reh}$ between $10^5$ and $10^{15}\,\mathrm{GeV}$ and $N_{reh}$ between 1 and 60, consistent with the big-bang nucleosynthesis lower bound of roughly 1 MeV.
  • With other parameter choices the same model can also cover the right-hand side of the Planck data, so the paper claims the $F(\phi,T)$ coupling can populate the whole currently allowed $(n_s,r)$ plane.

Reading between the lines

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

  • A direct consistency check a reader can perform is to compare the scalar-field equation of motion obtained from varying the action (2.9) with the one obtained from the continuity equation (2.11) and with equation (2.15); the three routes are not identical, so the reported $(n_s,r)$ values are conditional on which equation is the correct dynamics.
  • The same $F(\phi)T$ construction could be applied to other brane-inspired potentials, such as the KKLT form (3.2) or $\alpha$-attractor potentials, to see whether the low-$r$ coverage is generic to the coupling rather than a special feature of the chosen $F(\phi)$.
  • The reheating temperature range invites a consistency check against gravitino or modulus constraints from the underlying string compactification; the paper does not specify the inflaton decay channels or the matter-sector couplings, so an explicit particle-physics model would complete the argument.
  • If the slow-roll equation is corrected, the reported parameter ranges for $\beta$, $\mu$, and $m$ would need to be retuned; a systematic scan of this parameter space would show which regions of the Planck contours are genuinely accessible.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 4 minor

Summary. The manuscript studies single-field slow-roll inflation in the F(φ,T) modified-gravity framework, using a D-brane-inspired potential V(φ)=V0(1−m^4/φ^4) and a coupling F(φ)=(φ^5/μ)(1−m^4/φ^4). It derives Friedman equations and slow-roll parameters, computes the scalar spectral index n_s and the tensor-to-scalar ratio r for grids of β, μ, m and N, compares the results with Planck 2018 and BICEP/Keck contours, and includes a reheating analysis. The central claim is that this specific model accurately covers the left-hand side of the Planck n_s–r region.

Significance. If the derivation were secure and the comparison restrictive, the model could be a useful string-motivated example of F(φ,T) inflation, and the reheating analysis would add value. The paper presents explicit analytical forms for the slow-roll parameters and reports numerical scans over the parameter space. However, the central claim is not currently established: the field equations contain internal inconsistencies, the key slow-roll parameter η_V is asserted without derivation, and the parameter comparison is explicitly described as capable of producing any desirable values of n_s and r. These issues undermine the claimed agreement with the Planck data.

major comments (4)
  1. [Section 2, Eqs. (2.9), (2.11), (2.15)] The scalar field equation is stated in three mutually inconsistent forms. Direct variation of the action (2.1) with respect to φ gives Eq. (2.11), which contains a term βF_{,φ} φdot^2 and a factor (1+2βF) multiplying (φddot+3Hφdot). Eq. (2.9) instead has a coefficient 2βF_{,φ} φdot^2, and Eq. (2.15) drops the factor (1+2βF) from the φddot term. The terms that differ are dropped in the slow-roll limit, so the three forms reduce to the same Eq. (2.17), but the presence of algebra errors in two of the three versions means that the derivation of the slow-roll system was not checked and must be repaired.
  2. [Section 2, Eq. (2.19)] The formula for η_V is load-bearing because Eq. (2.26) gives n_s = 1 + 2η_V − 6ε_V, and all entries in Tables 1 and 2 and Figure 3 follow from it. Yet Eq. (2.19) is presented without derivation, and it is algebraically complex enough that an error would directly change all reported n_s values. Since the same derivation path produced the incorrect Eqs. (2.9) and (2.15), the authors should derive Eq. (2.19) step by step from the full scalar equation and verify the substituted form (3.7), for example by numerically integrating the background equations and comparing with the slow-roll approximation.
  3. [Section 3, paragraph after Eq. (3.9)] The sentence 'By adjusting appropriate values for the parameters, it is feasible to receive any desirable values for n_s and r' concedes that the five free parameters β, μ, m, V0 and N are tuned to reproduce the observed pair. No likelihood, chi-squared statistic, or parameter constraints are reported, and no physical priors are imposed. The agreement with the Planck contours is therefore an exercise in curve-fitting rather than an observational restriction on the model.
  4. [Section 2, Eqs. (2.21)–(2.28)] The scalar and tensor power spectra are obtained by inserting the modified Hubble parameter and potential into the standard single-field general-relativity formulas for A_s, n_s, r and n_t. The action (2.1) contains a non-minimal coupling of φ to the trace T, which can modify the quadratic action for curvature perturbations beyond the background replacement. Without a derivation of the perturbation equations in F(φ,T) gravity, the numerical values in Tables 1–2 and Figure 3 are not grounded in the theory.
minor comments (4)
  1. [Section 2, Eq. (2.20)] The e-fold integral appears to be an expansion to first order in β; the order of the approximation should be stated explicitly, and the smallness of βF in the parameter ranges used in the tables should be verified.
  2. [Section 3, Tables 1–2] The dimensions of the parameters β, μ, m and V0 are not specified; the authors should state whether these are measured in Planck units so that the numerical ranges are meaningful.
  3. [Section 3, Figure 3] The blue and pink curves in Figure 3 are not identified with their parameter ranges in the caption; a legend or explicit reference to Tables 1 and 2 would improve readability.
  4. [Section 3, Eqs. (3.10)–(3.19)] The notation ω_φ in Eq. (3.10) and ω_reh in Eq. (3.19) should be distinguished; as written, ω_reh is an effective equation-of-state parameter for the reheating epoch and should not be confused with the constant ω_φ used in Eq. (3.17).

Circularity Check

1 steps flagged · score 6.0 of 10

The Planck-coverage claim is a post-hoc parameter fit: the paper states that any desired (ns, r) can be obtained by adjusting free parameters, so the agreement is not an independent prediction.

  1. fitted input called prediction [Sec. 3, paragraph between Eq. (3.9) and Table 1]
    "By adjusting appropriate values for the parameters, it is feasible to receive any desirable values for “ ns” and “ r”."

    After computing ns and r from the slow-roll formulas, the paper explicitly states that any desired values of ns and r can be obtained by adjusting the free parameters β, μ, m, and N. Consequently, the subsequent claim that the model “covers the left-hand side of the Planck data” does not test the model: the parameter values in Tables 1–2 and Figure 3 are chosen so that the output lands in the target region. The agreement is therefore a restatement of the fitting procedure, not an independent prediction derived from first principles. The same procedure appears in the Conclusions: “By choosing suitable numerical values for ‘β’ and ‘μ’ we can also cover the entire Planck data surface,” confirming that the comparison is a parameter fit rather than a falsifiable prediction.

full rationale

The derivation of ns and r from the action is algebraically substantive: Eqs. (2.18)–(2.26) produce slow-roll expressions modified by F(φ) and β, and those formulas do not reduce at the equation level to the Planck contours. However, the paper's own operational test is a fit, not a prediction. After presenting r and ns, it states that any desirable values can be achieved by adjusting the parameters, and the chosen potentials are described as guaranteeing Planck-data compatibility. The tables and Figure 3 are therefore demonstrations of model flexibility with free parameters, not independent outcomes that could confirm or rule out the model. This is the fitted-input-called-prediction pattern. No load-bearing self-citation was found: references to the authors' earlier works are contextual and do not support the central claim. The inconsistency among Eqs. (2.9), (2.11), and (2.15), and the unproved ηV expression (2.19), are correctness risks that should be independently checked, but they are not circularity because they concern the internal validity of the derivation rather than the reduction of outputs to inputs. Overall, the central claim of Planck coverage reduces to a post-hoc fit, so a partial-circularity score of 6 is appropriate.

Assumptions & free parameters 5 free parameters · 4 assumptions · 0 invented entities

The central claim rests on several free parameters (β, µ, m, V0, N) and on an action whose field equations are mutually inconsistent. The specific forms of F(ϕ) and V(ϕ) are ad hoc choices justified only by the desire to fit Planck data.

free parameters (5)
  • β (coupling constant) = -0.004, -0.001, -0.0001
    Chosen by hand to shift predictions to the left side of the Planck ns-r plane; no independent theoretical determination.
  • µ (cut-off scale) = 1 to 200
    Scanned over a wide range to make the model cover the Planck 2018 1σ region; paper states that parameters can be adjusted to get any desired ns and r.
  • m (mass parameter) = 0.02, 0.08, 0.1, 0.3
    Tuned to adjust the shape of the D-brane potential and the resulting ns.
  • V0 (potential amplitude) = not fixed
    The overall scale cancels in ns and r, so it is left free; the Planck amplitude constraint As is quoted but not used to fix V0.
  • N (number of e-folds) = 50 to 60
    Conventionally chosen; the paper scans this range rather than deriving it from the model.
assumptions (4)
  • domain assumption The action S = ∫√-g[R/(2κ) + βF(ϕ)T + L_m] is a valid starting point for inflation.
    The F(ϕ)T coupling is motivated by modified gravity and string theory, but is introduced as an assumption.
  • standard math The slow-roll approximation φdot^2 << V, |φddot| << |3Hφdot|, and F,ϕ φdot^2 << Hφdot holds during inflation.
    Standard inflation technique.
  • ad hoc to paper The specific forms V(ϕ)=V0(1-m^4/ϕ^4) and F(ϕ)=(ϕ^5/µ)(1-m^4/ϕ^4) capture the D-brane dynamics.
    These forms are chosen to match Planck data rather than derived from a complete string theory construction; the paper provides only heuristic justifications.
  • ad hoc to paper The modified Klein-Gordon equation (2.15) is correct despite conflicting with Eq. (2.9) and (2.11).
    The paper uses (2.15) for slow-roll but does not resolve its inconsistency with the other two equations.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Observational Restrictions and Slow-Roll D-brane Inflation in the Special $F(\phi,T)$ Gravity." pith.science (2026). https://pith.science/paper/2AAECBQH

@misc{pith2026250723321,
  author       = {Pith},
  title        = {Pith review of: Observational Restrictions and Slow-Roll D-brane Inflation in the Special $F(\phi,T)$ Gravity},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/2AAECBQH}},
  note         = {Machine review of arXiv:2507.23321}
}
abstract

We shall investigate the inflation for the D-brane model, motivated by the modified gravity $F(\phi,T)$. This gravity has been recently introduced in the literature. The feasibility of the D-brane inflation theory in the $F(\phi,T)$-gravity has been studied in conjunction with the most recent Planck data. We shall analyze the slow-roll inflation in the context of the $F(\phi)T$-gravity, via the D-brane model. Then, we shall calculate the inflation dynamics to obtain the scalar spectral index ``$n_s$'' and the tensor-to-scalar ratio ``$r$''. Besides, we investigate the dynamics of the reheating for this model. Our model accurately covers the left-hand side of the Planck data and the D-brane inflation.

Figures

Figures reproduced from arXiv: 2507.23321 by the authors.

Figure 1
Figure 1. Using the Planck data alone (the grey area), or with the BICEP2/Keck data 2014 (red), and BAO (blue) data. The marginalized joint 68% and 95% CL areas for “ns” and “r” at k = 0.002M pc−1 were compared with the theoretical predictions of specific inflationary theories. It should be noted that dns/d ln k = 0 is assumed in the combined 68% and 95% CL areas. The lines display the predictions of several models as a funct… view at source ↗
Figure 2
Figure 2. The Planck 2018 results [8] for “ns” and “r” have been compared with the predictions of the simplest D-brane inflationary model with V ∼ 1 − ( m ϕ ) 4 and the α-attractors in the 2σ region. The dark (light) blue region on the panel represents the Planck 2018 1σ (2σ) region. The data are related to the CMB. On the panel, the quadratic T-model of the α-attractors at N = 50 and N = 60 has been represented by the two ye… view at source ↗
Figure 3
Figure 3. The predicted “r” and “ns” in our model. To compare, the outcome of the Einstein’s gravity (indicated by the red bar) has been displayed, which corresponds to the D-brane inflationary model with V ∼ 1 − m4 ϕ4 . The blue color is assigned when β = −0.004, m = 0.08 and 15 ≤ µ ≤ 50, while the pink color is assigned when β = −0.0001, m = 0.3 and 7 ≤ µ ≤ 21. At k = 0.002M pc−1 , “r” and “ns” are characterized by the conf… view at source ↗
Figures from the paper (4 more)
Figure 4
Figure 4. Figure 4: The left plot illustrates that how the universe’s temperature at the end of the reheating depends on the cosmic fluid’s behavior, parameterized by ωreh, which determines the expansion rate. For a fixed number of the e-folds Nreh, a faster expansion (higher ωreh) dilute…
Figure 5
Figure 5. Figure 5: This contour plot provides a comprehensive visualization of the reheating temperature landscape, shaped by the effects of the reheating equation of state and the duration. Given the energy density at the end of the inflation, the temperature after the reheating sensiti…
Figure 6
Figure 6. Figure 6: The left figure shows that how the reheating temperature varies with the equation of state parameter ωreh . The different durations (Nreh) are fixed. A larger ωreh (with the range from −1 to 1/3) means the faster energy dilution, which reduces the temperature. The key …
Figure 7
Figure 7. Figure 7: This contour map consolidates the dependence of the reheating temperature on both the equation of state and the reheating duration. This illustrates that the full parameter space has been spanned by ωreh and Nreh. The color gradation (log scale) demonstrates how the in…

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

62 extracted references · 56 canonical work pages

  1. [1]

    A. H. Guth, Phys. Rev. D 23 (1981) 347

  2. [2]

    Linde, Inflationary Cosmology, Phys

    A.D. Linde, Inflationary Cosmology, Phys. Lett. B 108 (1982) 389

  3. [4]

    Albrecht and P.J

    A. Albrecht and P.J. Steinhardt, Phys. Rev. Lett. 48 (1982) 1220

  4. [5]

    D. H. Lyth and A. Riotto, Phys. Rept. 314 (1999) 1

  5. [6]

    Cosmological inflation and large-scale structure

    A. R. Liddle and D. H. Lyth, “ Cosmological inflation and large-scale structure ”, Cambridge University Press, UK (2000)

  6. [7]

    BICEP, Keck collaboration, Phys. Rev. Lett. 127 (2021) 151301

  7. [8]

    Planck 2018 results. VI. Cosmological parameters

    Planck Collaboration, “ Planck 2018 results. VI. Cosmological parameters ”, A&A 641, A6 (2020), [arXiv:1807.06209 [astro-ph.CO]]

  8. [9]

    Planck 2013 results. XVI. Cosmological parameters

    Planck Collaboration, “ Planck 2013 results. XVI. Cosmological parameters ”, A&A 571, A16 (2014), [arXiv:1303.5076 [astro-ph.CO]]

Show all 62 references
  1. [10]

    Boubekeur and D

    L. Boubekeur and D. Lyth, JCAP 07 (2005) 010

  2. [11]

    Kallosh, A

    R. Kallosh, A. D. Linde, JCAP 09 (2019) 030

  3. [12]

    C. M. Lin, JCAP 06 (2020) 015

  4. [13]

    Kohri, C

    K. Kohri, C. M. Lin and D. H. Lyth, JCAP 12 (2007) 004

  5. [14]

    Dimopoulos, Phys

    K. Dimopoulos, Phys. Lett. B 809 (2020) 135688

  6. [15]

    German, JCAP 02 (2021) 034

    G. German, JCAP 02 (2021) 034

  7. [17]

    Hoffmann, D

    J. Hoffmann, D. Sloan, Phys. Rev. D 104 (2021) 123542

  8. [18]

    K. A. Olive, Phys. Rept. 190 (1990) 307-403. 24

  9. [19]

    Tegmark et al

    M. Tegmark et al. [SDSS Collaboration], “ Cosmological parameters from SDSS and WMAP, Phys. Rev. D 69 (2004) 103501 [astro-ph/0310723]

  10. [20]

    Polchinski, Phys

    J. Polchinski, Phys. Rev. Lett. 75 (1995) 4727

  11. [21]

    Kachru, R

    S. Kachru, R. Kallosh, A. D. Linde, et al. JCAP 0310 (2003) 013; G. Dvali, Q. Shafi and S. Solganik, Phys. Lett. B 450 (2001) 72-82

  12. [22]

    C. P. Burgess, M. Majumdar, D. Nolte, F. Quevedo, G. Rajesh and R. J. Zhang, JHEP 07 (2001) 047

  13. [23]

    Garcia-Bellido, R

    J. Garcia-Bellido, R. Rabadan and F. Zamora, JHEP 01 (2002) 036

  14. [24]

    Martin, C

    J. Martin, C. Ringeval and V. Vennin, Phys. Dark Univ. 5-6 (2014) 75-235

  15. [25]

    Kallosh, A

    R. Kallosh, A. Linde and Y. Yamada, JHEP 01 (2019) 008

  16. [26]

    Kallosh, A

    R. Kallosh, A. D. Linde, and A. Roest, JHEP 198 (2013)1311

  17. [27]

    J. J. M. Carrasco, R. Kallosh and A. Linde, JHEP 10 (2015) 147

  18. [28]

    Kallosh and A

    R. Kallosh and A. Linde, Phys. Rev. D 91 (2015) 083528

  19. [29]

    Kallosh and A

    R. Kallosh and A. Linde, Phys. Lett. B 798 (2019) 134970

  20. [30]

    Galante, R

    M. Galante, R. Kallosh, A. Linde and D. Roest, Phys. Rev. Lett. 114 (2015) 141302

  21. [31]

    Planck 2018 results. X. Constraints on inflation

    Planck Collaboration, “ Planck 2018 results. X. Constraints on inflation ”, A&A 641, A10 (2020), [arXiv:1807.06211 [astro-ph.CO]]

  22. [32]

    A. D. Linde, Phys. Lett. B 129 (1983) 177

  23. [33]

    Freese, J

    K. Freese, J. A. Frieman and A. V. Olinto, Phys. Rev. Lett. 65 (1990) 3233

  24. [34]

    F. C. Adams, J. R. Bond, K. Freese, J. A. Frieman and A. V. Olinto, Phys. Rev. D 47 (1993) 426

  25. [35]

    A. A. Starobinsky, Phys. Lett. B 91 (1980) 99

  26. [36]

    V. R. Ivanov, S. V. Ketov, E. O. Pozdeeva and S. Yu. Vernov, JCAP 03 (2022) 058. 25

  27. [37]

    Goncharov and A

    A. Goncharov and A. D. Linde, Sov. Phys. JETP 59 (1984) 930; G. Dvali and S.H. Tye, Phys. Lett. B 450 (1999) 72-82

  28. [38]

    E. E. Flanagan, Phys. Rev. Lett 92 (2004) 07110

  29. [39]

    Ferraris, M

    M. Ferraris, M. Francaviglia and I. Volovich. Class. Quant. Grav. 11 (1994) 1505- 1517

  30. [40]

    G. R. Bengochea and R. Ferraro, Phys. Rev. D 79 (2009) 124019; S. Teymourtashlou and D. Kamani, Eur. Phys. J. C 81 (2021) 761, arXiv:2108.10164 [hep-th]

  31. [41]

    Nojiri and S

    S. Nojiri and S. D. Odintsov, Phys. Lett. B 631 (2005) 1-6

  32. [42]

    Harko, F

    T. Harko, F. S. N. Lobo, S. Nojiri and S. D. Odintsov, Phys. Rev. D 84 (2011) 024020

  33. [43]

    Ferraro and F

    R. Ferraro and F. Fiorini, Phys. Rev. D 75 (2007) 084031

  34. [44]

    Nojiri and S

    S. Nojiri and S. D. Odintsov, Phys. Lett. B 599 (2004) 173

  35. [45]

    Allemandi, A

    G. Allemandi, A. Borowiec, M. Francaviglia and S.D. Odintsov, Phys. Rev. D 72 (2005) 063505; H. Daniali and D. Kamani, Nucl. Phys. B 975 (2022) 115683, arXiv:2202.09347 [hep-th]

  36. [46]

    Bertolami, C

    O. Bertolami, C. G. Boehmer, T. Harko and F.S.N. Lobo, Phys. Rev. D 75 (2007) 104016

  37. [47]

    Rudra, K

    P. Rudra, K. Giri. Nucl. Phys. B 967 (2021) 115428; D. Kamani, Phys. Lett. B 564 (2003) 123-131, arXiv:hep-th/0304236

  38. [48]

    Zhang, C

    X. Zhang, C. Y. Chen and Y. Reyimuaji. Phys. Rev. D 105 (2022) 043514

  39. [49]

    Dzhunushaliev, V

    V. Dzhunushaliev, V. Folomeev, B. Kleihaus, and J. Kunz. Eur. Phys. J. C 74 (2014) 1

  40. [50]

    C. Y. Chen and Y. H. Kung. Phys. Dark Univ. 35 (2022) 100956

  41. [51]

    X. Liu, T. Harko, and S. D. Liang. Eur. Phys. J. C 76 (2016) 1. 26

  42. [52]

    Rubio and C

    J. Rubio and C. Wetterich. Phys. Rev. D 96 (2017) 063509

  43. [53]

    Belhaj, M

    A. Belhaj, M. Benali, Y. Hassouni, and M. Lamaaoune. Int. J. Mod. Phys. A 38 (2023) 2350043

  44. [54]

    M. Gamonal. Phys. Dark Univ. 31 (2021) 100768

  45. [55]

    P. A. R. Ade et al. [Planck], Astron. Astrophys. 571 (2014) A22

  46. [56]

    Improved constraints on primordial gravitational waves using Planck, WMAP, and BICEP/Keck observations through the 2018 observing season

    Ade, Peter AR, et al. “ Improved constraints on primordial gravitational waves using Planck, WMAP, and BICEP/Keck observations through the 2018 observing season ”, Phys. Rev. Lett. 127. 15 (2021), 151301

  47. [57]

    D. S. Salopek, J. R. Bond and J. M. Bardeen. Phys. Rev. D 40 (1989) 1753

  48. [58]

    Cicoli, C

    M. Cicoli, C. P. Burgess and F. Quevedo. JCAP 0903 (2009) 013

  49. [59]

    Kachru and J

    S.B Giddings, S. Kachru and J. Polchinski, Phys. Rev. D 66 (2002) 106006

  50. [60]

    Silverstein and D

    E. Silverstein and D. Tong, Phys. Rev. D 70 (2004) 103505

  51. [61]

    P Burgess, JHEP 07 (2007) 047

    C. P Burgess, JHEP 07 (2007) 047

  52. [62]

    Kachru et al

    S. Kachru et al. Phys. Rev. D 68 (2003) 046005

  53. [63]

    I. R. Klebanov and M. J. Strassler, JHEP 08 (2000) 052

  54. [64]

    Kofman et al. Phys. Rev. D 56 (1997) 3258. 27

Pith tools

Reviewed August 6, 2026 · model on record in the stance chip above.