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REVIEW 2 major objections 5 minor 117 references

Tensor Catalyzed Decoherence of Primordial Scalar Fluctuations

T0 review · 2 major / 5 minor · reviewed 2026-08-15 · deepseek-v4-flash

Pith's one-line read The leading decoherence of scalar curvature perturbations in single-clock inflation is not slow-roll suppressed; it is of order $(H/M_p)^2$, matching tensor-mode decoherence.

desk verdict Scalar curvature perturbations decohere at order (H/M_p)^2 without slow-roll suppression via a mixed scalar-tensor channel — a genuine correction to the literature, and the calculation holds up on close reading. read the letter →

arxiv 2607.22914 v1 pith:333PVI7J submitted 2026-07-24 hep-th

classification hep-th
keywords inflationarydecoherencescalarcurvatureperturbationstensormodespurityopenquantumsystemsslow-rollsuppressionresummedlate-timeevolutionprimordialfluctuations
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 claims that the leading decoherence of long-wavelength scalar curvature perturbations in the simplest single-clock inflationary models is not suppressed by the slow-roll parameter $\epsilon_1$, contrary to all earlier calculations. The dominant effect comes from a cubic interaction that couples the observed scalar mode to one short-wavelength tensor and one short-wavelength scalar simultaneously, so the scalar and tensor environments must be evolved together. For a Bunch-Davies initial state the perturbative purity is predicted to be $\gamma_k(z) \simeq 1 - \frac{32}{45\pi^2}\frac{H^2}{M_p^2}\frac{k}{k_{\rm UV}}\left(\frac{aH}{k_{\rm UV}}\right)^2$, with a resummed late-time form $\gamma_k = 1/\sqrt{1+\Xi_k}$, and the leading contribution is ultraviolet finite. If correct, scalar and tensor primordial fluctuations decohere at comparable rates, removing an asymmetry assumed in most previous estimates.

What carries the argument

The load-bearing mechanism is the tensor-catalyzed cubic interaction $S_{\rm int} = \int d\eta\, d^3x\, \epsilon_1 M_p^2 a^2 \gamma_{ij}\partial^i \zeta \partial^j \zeta$, in which the system field $\zeta$ is coupled to a short-wavelength tensor $\gamma_{ij}$ and a short-wavelength scalar $\partial\zeta$. This interaction produces a Lindblad-like master equation whose decoherence coefficients are governed by the environmental correlator $D_k(\eta,\eta') = k_i k_j \langle \gamma_{ia}\partial_a \zeta(\eta)\, \gamma_{jb}\partial_b \zeta(\eta')\rangle$, with momentum integrals restricted to the environment region $k>k_{\rm UV}$. The small-$z$ asymptotics of the resulting integrals $\tilde J^{\zeta\zeta}$, $\tilde J^{\zeta p}$ give the leading purity loss, and the time-local, Gaussian character of the evolution in the super-Hubble limit allows the secular growth to be resummed into $\gamma_k = 1/\sqrt{1+\Xi_k}$.

What would settle it

Evaluate the same purity evolution with the environmental momentum integrals extended to $k<k_{\rm IR}$ while keeping $k_{\rm UV}$ fixed; if that contribution is not negligible compared with $\frac{32}{45\pi^2}\frac{H^2}{M_p^2}\frac{k}{k_{\rm UV}}\left(\frac{aH}{k_{\rm UV}}\right)^2$, the claimed leading result is incomplete. A second check is to include quartic self-interactions in the transport equations for the equal-time correlators $\Sigma_{ij}$ in the deep super-Hubble regime and see whether they alter the resummed purity at order $H^2/M_p^2$.

Watch

Extended reading notes

Core claim

The central discovery is that the leading contribution to the decoherence of scalar curvature perturbations in minimal single-clock inflation is of order $(H/M_p)^2$, the same order as tensor-mode decoherence, rather than being multiplied by the slow-roll parameter $\epsilon_1$. This follows from the cubic interaction $S_{\rm int} = \int d\eta\, d^3x\, \epsilon_1 M_p^2 a^2 \gamma_{ij}\partial^i \zeta \partial^j \zeta$, evaluated with $\gamma_{ij}$ and one of the $\partial \zeta$ factors as environmental fields and the remaining $\zeta$ as the system. In terms of the canonically normalized variable $v$ the correlators of this interaction are $\epsilon_1$-independent, which removes the slow-roll suppression. The paper argues that all other cubic interactions contribute at higher order in $\epsilon_1$ or $H/M_p$, making the calculation complete at this order, and it verifies that the leading decoherence is UV finite and becomes time-local and Gaussian in the deep super-Hubble regime.

Load-bearing premise

The calculation assumes that the environment consists only of modes with comoving momenta above a fixed cutoff $k_{\rm UV}$, and that modes below a long-wavelength cutoff $k_{\rm IR}$ modify only the background cosmology rather than the decoherence rate; if very long-wavelength environmental modes contribute at the same order, the leading coefficient would change.

Editorial extensions

If this is right

  • Scalar curvature perturbations and tensor perturbations lose purity at the same parametric rate, of order $(H/M_p)^2$, during inflation.
  • Earlier estimates that found scalar decoherence slow-roll suppressed missed the leading contribution because they did not evolve scalar and tensor environments simultaneously.
  • The leading decoherence is ultraviolet finite, and the late-time purity is reliably given by $\gamma_k = 1/\sqrt{1+\Xi_k}$ even when naive perturbation theory fails.
  • The breakdown of perturbation theory in the purity does not change the standard prediction for the amplitude of primordial curvature fluctuations, because the leading $\Sigma_{11}$ coefficient is protected by the consistency constraints.

Reading between the lines

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

  • If scalar and tensor modes decohere at comparable rates, searches for quantum signatures in the CMB should treat gravitational-wave modes as an environmental noise source for scalar perturbations, not only as a separate observable.
  • The tensor-catalysis mechanism suggests a pattern: whenever a system field couples cubically to two different environmental species, the mixed environment can dominate over same-species environments even if each individual coupling is slow-roll suppressed.
  • A testable extension is to let the system-environment split be time-dependent or to include the neglected $k<k_{\rm IR}$ modes; the paper's rate would then serve as a lower bound if those modes add decoherence.
  • One could verify the resummation numerically by evolving the Gaussian transport equations for $\Sigma_{ij}$ with the computed coefficient matrices and comparing the late-time purity to $1/\sqrt{1+\Xi_k}$.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

2 major / 5 minor

Summary. This paper computes the leading gravitational decoherence rate for long-wavelength scalar curvature perturbations ζ in minimal single-field slow-roll inflation, treating short-wavelength scalar and tensor metric modes as an environment. The authors identify the cubic interaction γ_ij ∂^i ζ ∂^j ζ as the only channel that avoids slow-roll suppression when one ζ is the system and γ plus the other ζ form the environment. Using the Nakajima-Zwanzig/TCL2 open-EFT formalism, they evaluate the environmental correlators (Appendices A and B), obtain a time-local Lindblad-like master equation, and derive the perturbative purity γ_k(z) ≃ 1 − (32/45π^2)(H/M_p)^2 (k/k_UV)(aH/k_UV)^2 (Eq. 3.31). They further show that in the deep super-Hubble limit the evolution is Gaussian and time-local, derive transport equations for the covariance matrix, and resum the secular growth to give γ_k = (1 + Ξ_k)^(−1/2) (Eqs. 1.5 and 4.36–4.38). The paper claims to provide the first complete leading-order calculation, with the key novelties being the simultaneous inclusion of scalar and tensor environments and the absence of ε_1 suppression.

Significance. If correct, the result is significant: it overturns the previously asserted slow-roll suppression of scalar-mode decoherence and places scalar and tensor decoherence at the same order (H/M_p)^2. The derivation is substantial and mostly self-contained: the momentum and time integrals are presented in detail, the ε_1 cancellation is transparent after switching to canonical variables, the leading result is shown to be UV finite, and the positivity of the dominant Lindblad coefficient is checked. The paper is commendably explicit in flagging its own assumptions and limitations (footnotes 6 and 8), but this also means the advertised 'complete calculation' and 'reliable resummation' claims are stronger than what is actually demonstrated. The work will be of interest to the quantum-to-classical transition and inflationary EFT communities.

major comments (2)
  1. [§2.2, footnote 6; §5] The abstract and §5 state that this is the 'first complete calculation of the leading contribution' and that all contributing interactions at leading order are included. However, footnote 6 in §2.2 labels the neglect of modes k < k_IR as 'an assumption that should be checked,' and the entire calculation restricts the environment to k > k_UV. If very long-wavelength environmental modes contribute at the same order, the coefficient in Eq. (3.31) and the resummed Ξ_k in Eq. (4.38) would change. The paper does treat the result as a lower bound in footnote 6, but that qualification does not appear in the abstract or in the concluding summary. This does not affect the headline scaling (decoherence at order (H/M_p)^2 with no ε_1 suppression), but it does bear directly on the completeness claim. Please either supply a quantitative argument that k < k_IR modes contribute only at subleading order, or revise the 'complete calculation' language to state explicitly that the result is a leading contribution for the chosen split and a lower bound in a realistic framework.
  2. [§4.1, footnote 8; §4.3] The resummed late-time purity (1.5) is derived from the time-local Gaussian transport equations (4.10) together with the small-z asymptotic forms of the J^ab kernels. Footnote 8 states that quartic self-interactions have not been computed and that, while they can affect the correlators Σ_ij generally, they are argued (in [53]) not to affect the purity. Since the resummation is one of the two headline results and is presented as reliable beyond the breakdown of perturbation theory, the claim that quartic contributions drop out of the purity evolution should be demonstrated in this paper, or the resummation section should be qualified. In particular, Eqs. (4.27)–(4.29) rely on the exact form of the Lindblad dissipator; any omitted quartic dissipative terms would feed into ∂_η det Σ and hence into γ_k. Please include the argument here, or reproduce the relevant steps from [53] rather than citing it only.
minor comments (5)
  1. [Eq. (1.6)] The sentence defining the operators reads 'O_1 = ζ_k and O_1 = p_k'; the second assignment should be O_2 = p_k.
  2. [Footnote 2] The phrase 'For readers who are double-parked Appendix 2 contains a quick summary' appears to contain a typo and refers to an appendix labeled 'A' in the text; please rephrase and correct the appendix reference.
  3. [Eq. (3.13)] The definition Z^2 := H^2/(2ε_1 k^3 M_p^2) = 1/(z_s^2 z_k^2) introduces z_k without defining it; please define z_k or write the expression directly in terms of z_s.
  4. [Eq. (3.18)] The coefficients c^{pz_r} and c^{pz_i} are said to be divergent and are not quoted; the text explains that they appear in slow-roll-suppressed terms and may cancel against other interactions. This is acceptable for the leading-order claim, but the sentence 'we have nonetheless computed their leading contributions to verify their subdominance' is misleading when the coefficients are regulator-dependent; please rephrase to describe what was actually verified.
  5. [References] Reference [94] is a placeholder with a 'to appear' designation and an incomplete arXiv number; it should be updated before publication.

Circularity Check

0 steps flagged · score 2.0 of 10

No significant circularity: the leading non-slow-roll decoherence result is derived from the standard inflationary action without fitted inputs; framework self-citations are not load-bearing.

full rationale

The central perturbative claim, Eq. (3.31), is obtained by direct calculation from the standard action (2.1): the selected cubic vertex (3.1), ε1 M_p^2 a^2 γ_ij ∂^i ζ ∂^j ζ, is written with the canonical variable v = z_s ζ, and the Bunch-Davies mode functions (2.11) carry one factor 1/sqrt(ε1) per environmental ζ mode. The ε1 dependence in the coupling is therefore compensated in the environment correlator, leaving the ε1-independent integrals (3.16)-(3.17), evaluated explicitly in Appendix B. No parameter is fitted to the decoherence result: H, M_p, ε1, and k_UV are background or coarse-graining choices fixed before the purity calculation, and the final coefficient 32/(45π^2) emerges from the integrals. The paper does cite its own prior work, [53] and [64], for the open-EFT framework and Gaussian/time-local simplifications, and states that 'many of the arguments of §2 and (3) are compressed versions of arguments in [53] and [64]'; however, the necessary framework is also reproduced in Appendices A and C, and the new tensor-catalyzed contribution is computed in the present paper rather than imported. The explicitly flagged limitations are not hidden circularity: footnote 6 says the neglect of k < k_IR modes 'is an assumption that should be checked' and regards the result as a lower bound, and footnote 8 notes that quartic self-interactions were not computed for the Σ transport equations while arguing they do not affect purity. Neither caveat injects the target result as an input. The derivation is self-contained against the standard inflationary cubic action from Maldacena [75], so the circularity score is low.

Assumptions & free parameters 1 free parameters · 5 assumptions · 0 invented entities

The central result depends on the standard single-clock inflationary action, the Bunch-Davies vacuum, and the choice of a sharp momentum cutoff k_UV separating system from environment. No free parameters are fitted to the decoherence outcome; H, M_p, and epsilon_1 are background inputs, and k_UV is an arbitrary scheme choice acknowledged to affect the coefficient (Eq. 5.1). The claimed completeness at leading order rests on the cubic-interaction list of [75] and on the small-z expansions that justify the Gaussian, time-local evolution; both are argued, not formally proven. No new entities are introduced.

free parameters (1)
  • k_UV
    Comoving scale separating system from environment. The leading purity correction is proportional to k/k_UV (Eq. 5.1), so the numerical coefficient depends on this arbitrary split, as the paper acknowledges.
assumptions (5)
  • domain assumption Bunch-Davies vacuum initial state in the remote past
    Used to set initial conditions for the reduced density matrix (Eq. 2.15, A.21). If the initial state differed, the decoherence rate would change.
  • domain assumption The cubic interactions listed in [75] are the complete set of leading-order interactions
    Completeness of the leading-order result relies on this list; used in Section 3.1 and Appendix B.
  • domain assumption The reduced state remains Gaussian and evolves time-locally at leading order in the deep super-Hubble regime
    Argued from momentum conservation and the small-z expansion (Sections A.3 and A.4), but checked only to leading order; footnote 8 caveats quartic self-interactions for correlators Sigma_ij.
  • domain assumption Modes with k < k_IR can be neglected
    Footnote 6 states this should be checked; neglect could affect the coefficient.
  • standard math Wick's theorem applied to environmental correlators
    Used in Section 3.2 and Appendix B to evaluate the environment two-point functions.

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Pith. "Pith review of Tensor Catalyzed Decoherence of Primordial Scalar Fluctuations." pith.science (2026). https://pith.science/paper/333PVI7J

@misc{pith2026260722914,
  author       = {Pith},
  title        = {Pith review of: Tensor Catalyzed Decoherence of Primordial Scalar Fluctuations},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/333PVI7J}},
  note         = {Machine review of arXiv:2607.22914}
}
abstract

We provide the first complete calculation of the leading contribution to the decoherence of primordial fluctuations in the scalar part of the metric fluctuations within simplest, single-clock, inflationary models, assuming decoherence comes from gravitational interactions with an environment made up of the other, unmeasured, short-wavelength scalar and tensor modes. We include the contributions from {\it all} of the contributing interactions at leading order in powers of $(H/M_p)^2$ and of the slow-roll parameter $\epsilon_1$. Unlike all extant calculations in the literature we find a result that is {\it not} slow-roll suppressed (and so is the same order of magnitude as tensor-mode decoherence). The difference arises because the dominant decoherence comes from interactions that involve {\it both} the tensor and scalar environments simultaneously (and so are missed when they are examined separately). We verify that the leading contributions to decoherence are UV finite (as they must be). We confirm that the interactions driving decoherence become time-local and Gaussian in the deep super-Hubble inflationary regime and show how this can be used to reliably compute the evolution of the purity in the late-time regime relevant for observations (where naive perturbation theory is known to break down). The same derivation shows explicitly why the effects that undermine perturbation theory for decoherence do not also undermine the basic inflationary prediction for the amplitude of primordial fluctuations (in agreement with general arguments).2

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Reference graph

Works this paper leans on

117 extracted references · 10 canonical work pages

  1. [53]

    C. P. Burgess, R. Holman, G. Kaplanek, J. Martin and V. Vennin,Minimal decoherence from inflation,JCAP07(2023) 022, [2211.11046]

  2. [64]

    C. P. Burgess, R. Holman and G. Kaplanek,Inflationary decoherence from the gravitational floor,JCAP02(2026) 042, [2509.07769]

  3. [1]

    R. H. Brandenberger,Modern cosmology and structure formation, inTheoretical Advanced Study Institute in Elementary Particle Physics (TASI 94): CP Violation and the limits of the Standard Model, 10, 1994.astro-ph/9411049

  4. [2]

    Mukhanov,Physical Foundations of Cosmology

    V. Mukhanov,Physical Foundations of Cosmology. Cambridge University Press, Oxford, 2005, 10.1017/CBO9780511790553

  5. [3]

    Weinberg,Cosmology

    S. Weinberg,Cosmology. Oxford University Press, 2008

  6. [4]

    Baumann,Cosmology

    D. Baumann,Cosmology. Cambridge University Press, 7, 2022, 10.1017/9781108937092

  7. [5]

    Martin, V

    J. Martin, V. Vennin and P. Peter,Cosmological Inflation and the Quantum Measurement Problem,Phys. Rev.D86(2012) 103524, [1207.2086]

  8. [6]

    Maldacena,A model with cosmological Bell inequalities,Fortsch

    J. Maldacena,A model with cosmological Bell inequalities,Fortsch. Phys.64(2016) 10–23, [1508.01082]

Show all 117 references
  1. [7]

    Martin and V

    J. Martin and V. Vennin,Quantum Discord of Cosmic Inflation: Can we show that CMB Anisotropies are of Quantum-Mechanical Origin?,Phys. Rev.D93(2016) 023505, [1510.04038]

  2. [8]

    Martin and V

    J. Martin and V. Vennin,Obstructions to Bell CMB Experiments,Phys. Rev.D96(2017) 063501, [1706.05001]

  3. [9]

    Choudhury, S

    S. Choudhury, S. Panda and R. Singh,Bell violation in the Sky,Eur. Phys. J. C77(2017) 60, [1607.00237]

  4. [10]

    Martin and V

    J. Martin and V. Vennin,Observational constraints on quantum decoherence during inflation, 1801.09949

  5. [11]

    Green and R

    D. Green and R. A. Porto,Signals of a Quantum Universe,Phys. Rev. Lett.124(2020) 251302, [2001.09149]

  6. [12]

    Espinosa-Portal´ es and V

    L. Espinosa-Portal´ es and V. Vennin,Real-space Bell inequalities in de Sitter,JCAP07(2022) 037, [2203.03505]

  7. [13]

    Brahma, A

    S. Brahma, A. Berera and J. C. Figueroa,Universal signature of quantum entanglement across cosmological distances,Classical and Quantum Gravity(2022)

  8. [14]

    Martin, A

    J. Martin, A. Micheli and V. Vennin,Discord and decoherence,JCAP04(2022) 051, [2112.05037]

  9. [15]

    Martin, A

    J. Martin, A. Micheli and V. Vennin,Comparing quantumness criteria,EPL142(2023) 18001, [2211.10114]

  10. [16]

    Piotrak, T

    M. Piotrak, T. Colas, A. Alonso-Serrano and A. Serafini,Quantum estimation of cosmological parameters,JHEP02(2026) 199, [2507.12228]

  11. [17]

    Micheli, Y

    A. Micheli, Y. Oshima and T. Takahashi,Quantum state of interacting primordial inhomogeneities: Desqueezing and decoherence,Phys. Rev. D113(2026) 123554, [2512.17622]

  12. [18]

    S. S. Haque, G. Jafari and B. Underwood,Inflation is Not Magic,2512.10126

  13. [19]

    Liu, L.-H

    S.-C. Liu, L.-H. Liu, B. Li, H.-Q. Zhang and P.-Z. He,Quantum-information diagnostics of cosmological perturbations with nontrivial sound speed in inflation,2604.21755. – 42 –

  14. [20]

    Ireland and V

    A. Ireland and V. Vennin,When inflationary perturbations refuse to classicalise: the role of non-Gaussianity in Wigner negativity,JCAP07(2026) 042, [2601.22219]

  15. [21]

    Cielo, S

    M. Cielo, S. Scarlatella, G. Mangano and O. Pisanti,When the Environment Speaks: Quantum Signatures in Non-Attractor Inflation,2607.07602

  16. [22]

    Sakagami,Evolution From Pure States Into Mixed States in De Sitter Space,Prog

    M. Sakagami,Evolution From Pure States Into Mixed States in De Sitter Space,Prog. Theor. Phys.79(1988) 442

  17. [23]

    R. H. Brandenberger, R. Laflamme and M. Mijic,Classical Perturbations From Decoherence of Quantum Fluctuations in the Inflationary Universe,Mod. Phys. Lett. A5(1990) 2311–2318

  18. [24]

    Matacz,The Emergence of classical behavior in the quantum fluctuations of a scalar field in an expanding universe,Class

    A. Matacz,The Emergence of classical behavior in the quantum fluctuations of a scalar field in an expanding universe,Class. Quant. Grav.10(1993) 509–516

  19. [25]

    Lombardo and F

    F. Lombardo and F. D. Mazzitelli,Coarse graining and decoherence in quantum field theory, Phys. Rev. D53(1996) 2001–2011, [hep-th/9508052]

  20. [26]

    A. O. Barvinsky and A. Y. Kamenshchik,Preferred basis in quantum theory and the problem of classicalization of the quantum universe,Phys. Rev. D52(1995) 743–757

  21. [27]

    Polarski and A

    D. Polarski and A. A. Starobinsky,Semiclassicality and decoherence of cosmological perturbations,Class. Quant. Grav.13(1996) 377–392, [gr-qc/9504030]

  22. [28]

    Calzetta and B

    E. Calzetta and B. L. Hu,Quantum fluctuations, decoherence of the mean field, and structure formation in the early universe,Phys. Rev. D52(1995) 6770–6788, [gr-qc/9505046]

  23. [29]

    Kubotani, T

    H. Kubotani, T. Uesugi, M. Morikawa and A. Sugamoto,Classicalization of quantum fluctuation in inflationary universe,Prog. Theor. Phys.98(1997) 1063–1080, [gr-qc/9701043]

  24. [30]

    Kiefer and D

    C. Kiefer and D. Polarski,Emergence of classicality for primordial fluctuations: Concepts and analogies,Annalen Phys.7(1998) 137–158, [gr-qc/9805014]

  25. [31]

    A. O. Barvinsky, A. Yu. Kamenshchik, C. Kiefer and I. V. Mishakov,Decoherence in quantum cosmology at the onset of inflation,Nucl. Phys.B551(1999) 374–396, [gr-qc/9812043]

  26. [32]

    Kiefer, D

    C. Kiefer, D. Polarski and A. A. Starobinsky,Quantum to classical transition for fluctuations in the early universe,Int. J. Mod. Phys. D7(1998) 455–462, [gr-qc/9802003]

  27. [33]

    Bellini,Decoherence of gauge invariant metric fluctuations during inflation,Phys

    M. Bellini,Decoherence of gauge invariant metric fluctuations during inflation,Phys. Rev.D64 (2001) 043507, [gr-qc/0105011]

  28. [34]

    F. C. Lombardo and D. Lopez Nacir,Decoherence during inflation: The Generation of classical inhomogeneities,Phys. Rev.D72(2005) 063506, [gr-qc/0506051]

  29. [35]

    Burgess, R

    C. Burgess, R. Holman and D. Hoover,Decoherence of inflationary primordial fluctuations, Phys.Rev.D77(2008) 063534, [astro-ph/0601646]

  30. [36]

    Prokopec and G

    T. Prokopec and G. I. Rigopoulos,Decoherence from Isocurvature perturbations in Inflation, JCAP0711(2007) 029, [astro-ph/0612067]

  31. [37]

    J. W. Sharman and G. D. Moore,Decoherence due to the Horizon after Inflation,JCAP0711 (2007) 020, [0708.3353]

  32. [38]

    Weenink and T

    J. Weenink and T. Prokopec,On decoherence of cosmological perturbations and stochastic inflation,1108.3994

  33. [39]

    Kiefer and D

    C. Kiefer and D. Polarski,Why do cosmological perturbations look classical to us?,Adv. Sci. Lett. 2(2009) 164–173, [0810.0087]

  34. [40]

    Kiefer, F

    C. Kiefer, F. Queisser and A. A. Starobinsky,Cosmological Constant from Decoherence,Class. Quant. Grav.28(2011) 125022, [1010.5331]

  35. [41]

    Franco and E

    M. Franco and E. Calzetta,Decoherence in the cosmic background radiation,Class. Quant. Grav. 28(2011) 145024, [1103.0188]. – 43 –

  36. [42]

    C. P. Burgess, R. Holman, G. Tasinato and M. Williams,EFT Beyond the Horizon: Stochastic Inflation and How Primordial Quantum Fluctuations Go Classical,JHEP03(2015) 090, [1408.5002]

  37. [43]

    Boyanovsky,Effective field theory during inflation: Reduced density matrix and its quantum master equation,Phys

    D. Boyanovsky,Effective field theory during inflation: Reduced density matrix and its quantum master equation,Phys. Rev. D92(2015) 023527, [1506.07395]

  38. [44]

    Nelson,Quantum Decoherence During Inflation from Gravitational Nonlinearities,JCAP 1603(2016) 022, [1601.03734]

    E. Nelson,Quantum Decoherence During Inflation from Gravitational Nonlinearities,JCAP 1603(2016) 022, [1601.03734]

  39. [45]

    T. J. Hollowood and J. I. McDonald,Decoherence, discord and the quantum master equation for cosmological perturbations,Phys. Rev. D95(2017) 103521, [1701.02235]

  40. [46]

    Shandera, N

    S. Shandera, N. Agarwal and A. Kamal,Open quantum cosmological system,Phys. Rev. D98 (2018) 083535, [1708.00493]

  41. [47]

    K. K. Boddy, S. M. Carroll and J. Pollack,How decoherence affects the probability of slow-roll eternal inflation,Physical Review D96(2017) 023539

  42. [48]

    N. Bao, A. Chatwin-Davies, J. Pollack and G. N. Remmen,Cosmological Decoherence from Thermal Gravitons,JHEP08(2020) 065, [1911.10207]

  43. [49]

    Brahma, O

    S. Brahma, O. Alaryani and R. Brandenberger,Entanglement entropy of cosmological perturbations,Phys. Rev. D102(2020) 043529, [2005.09688]

  44. [50]

    Banerjee, S

    S. Banerjee, S. Choudhury, S. Chowdhury, J. Knaute, S. Panda and K. Shirish,Thermalization in quenched open quantum cosmology,Nucl. Phys. B996(2023) 116368, [2104.10692]

  45. [51]

    Brahma, A

    S. Brahma, A. Berera and J. Calder´ on-Figueroa,Quantum corrections to the primordial tensor spectrum: Open EFTs & Markovian decoupling of UV modes,JHEP08(2022) 225, [2206.05797]

  46. [52]

    Colas, J

    T. Colas, J. Grain and V. Vennin,Benchmarking the cosmological master equations,2209.01929

  47. [54]

    Daddi Hammou and N

    A. Daddi Hammou and N. Bartolo,Cosmic decoherence: primordial power spectra and non-Gaussianities,JCAP04(2023) 055, [2211.07598]

  48. [55]

    Colas, J

    T. Colas, J. Grain and V. Vennin,Quantum recoherence in the early universe,EPL142(2023) 69002, [2212.09486]

  49. [56]

    C. M. Sou, D. H. Tran and Y. Wang,Decoherence of cosmological perturbations from boundary terms and the non-classicality of gravity,JHEP04(2023) 092, [2207.04435]

  50. [57]

    Boutivas, D

    K. Boutivas, D. Katsinis, G. Pastras and N. Tetradis,Entanglement in cosmology,JCAP04 (2024) 017, [2310.17208]

  51. [58]

    Tinwala, A

    A. Tinwala, A. Narang, S. Mohanty and S. Panda,Open EFT treatment of Inflation with Thermal Initial Conditions,2402.18494

  52. [59]

    Colas, C

    T. Colas, C. de Rham and G. Kaplanek,Decoherence out of fire: purity loss in expanding and contracting universes,JCAP05(2024) 025, [2401.02832]

  53. [60]

    Colas, J

    T. Colas, J. Grain, G. Kaplanek and V. Vennin,In-in formalism for the entropy of quantum fields in curved spacetimes,JCAP08(2024) 047, [2406.17856]

  54. [61]

    de Kruijf and N

    J. de Kruijf and N. Bartolo,The effect of quantum decoherence on inflationary gravitational waves,JCAP11(2024) 041, [2408.02563]

  55. [62]

    C. P. Burgess, T. Colas, R. Holman, G. Kaplanek and V. Vennin,Cosmic purity lost: perturbative and resummed late-time inflationary decoherence,JCAP08(2024) 042, [2403.12240]. – 44 –

  56. [63]

    Brahma, J

    S. Brahma, J. Calder´ on-Figueroa and X. Luo,Time-convolutionless cosmological master equations: late-time resummations and decoherence for non-local kernels,JCAP08(2025) 019, [2407.12091]

  57. [65]

    Cespedes, S

    S. Cespedes, S. de Alwis and F. Quevedo,Cosmology, Decoherence and the Second Law, 2509.07077

  58. [66]

    de Kruijf, G

    J. de Kruijf, G. Galloni and N. Bartolo,The first data-driven bounds on the quantum decoherence of inflationary gravitational waves,2511.14727

  59. [67]

    Sano and J

    F. Sano and J. Tokuda,False and genuine decoherence in the early universe: a local observer and time-averaged observables,JHEP07(2025) 266, [2504.10472]

  60. [68]

    Lopez and N

    F. Lopez and N. Bartolo,Quantum signatures and decoherence during inflation from deep subhorizon perturbations,2503.23150

  61. [69]

    Cielo, S

    M. Cielo, S. Scarlatella, G. Mangano, O. Pisanti and L. Hamaide,Quantum Recoherence in Presence of Excited States in the Early Universe,2512.01932

  62. [70]

    Christie, J

    R. Christie, J. Joo, G. Kaplanek, V. Vennin and D. Wands,Cosmic Lockdown: When Decoherence Saves the Universe from Tunneling,2512.14204

  63. [71]

    Choudhury,Quantum Discord in de-Sitter Axiverse,2512.24802

    S. Choudhury,Quantum Discord in de-Sitter Axiverse,2512.24802

  64. [72]

    S. S. Haque and B. Underwood,A Landscape of Cosmological Decoherence,2606.07663

  65. [73]

    Christie, J

    R. Christie, J. Joo, G. Kaplanek, V. Vennin and D. Wands,Quantum Stochastic Inflation, 2606.12636

  66. [74]

    C. P. Burgess, T. Colas, R. Holman and G. Kaplanek,Does decoherence violate decoupling?, JHEP02(2025) 204, [2411.09000]

  67. [75]

    J. M. Maldacena,Non-Gaussian features of primordial fluctuations in single field inflationary models,JHEP05(2003) 013, [astro-ph/0210603]

  68. [76]

    Ye and Y.-S

    G. Ye and Y.-S. Piao,Quantum decoherence of primordial perturbations through nonlinear scaler-tensor interaction,arXiv:1806.07672(2018)

  69. [77]

    Lindblad,On the Generators of Quantum Dynamical Semigroups,Commun

    G. Lindblad,On the Generators of Quantum Dynamical Semigroups,Commun. Math. Phys.48 (1976) 119

  70. [78]

    Gorini, A

    V. Gorini, A. Frigerio, M. Verri, A. Kossakowski and E. C. G. Sudarshan,Properties of Quantum Markovian Master Equations,Rept. Math. Phys.13(1978) 149

  71. [79]

    Breuer, E.-M

    H.-P. Breuer, E.-M. Laine and J. Piilo,Measure for the Degree of Non-Markovian Behavior of Quantum Processes in Open Systems,Phys. Rev. Lett.103(2009) 210401, [0908.0238]

  72. [80]

    Rivas, S

    ´A. Rivas, S. F. Huelga and M. B. Plenio,Entanglement and Non-Markovianity of Quantum Evolutions,Phys. Rev. Lett.105(2010) 050403, [0911.4270]

  73. [81]

    M. B. Plenio, S. F. Huelga and ´A. Rivas,Quantum non-Markovianity: characterization, quantification and detection,Rept. Prog. Phys.77(2014) 094001, [1405.0303]

  74. [82]

    Breuer, E.-M

    H.-P. Breuer, E.-M. Laine, J. Piilo and B. Vacchini,Colloquium: Non-Markovian dynamics in open quantum systems,Rev. Mod. Phys.88(2016) 021002, [1505.01385]

  75. [83]

    Di´ osi and L

    L. Di´ osi and L. Ferialdi,General Non-Markovian structure of Gaussian Master and Stochastic Schr¨ odinger Equations,Phys. Rev. Lett.113(2014) 200403, [1408.1273]

  76. [84]

    Ferialdi,Dissipation in the Caldeira-Leggett model,Phys

    L. Ferialdi,Dissipation in the Caldeira-Leggett model,Phys. Rev. A95(2017) 052109, [1701.05024]. – 45 –

  77. [85]

    Assassi, D

    V. Assassi, D. Baumann and D. Green,Symmetries and Loops in Inflation,JHEP02(2013) 151, [1210.7792]

  78. [86]

    C. W. Misner, K. S. Thorne and J. A. Wheeler,Gravitation. W. H. Freeman, San Francisco, 1973

  79. [87]

    Weinberg,Gravitation and Cosmology: Principles and Applications of the General Theory of Relativity

    S. Weinberg,Gravitation and Cosmology: Principles and Applications of the General Theory of Relativity. John Wiley and Sons, New York, 1972

  80. [88]

    Kodama and M

    H. Kodama and M. Sasaki,Cosmological Perturbation Theory,Prog. Theor. Phys. Suppl.78 (1984) 1–166

  81. [89]

    V. F. Mukhanov, H. Feldman and R. H. Brandenberger,Theory of cosmological perturbations. Part 1. Classical perturbations. Part 2. Quantum theory of perturbations. Part 3. Extensions, Phys. Rept.215(1992) 203–333

  82. [90]

    V. F. Mukhanov and G. Chibisov,Quantum Fluctuation and Nonsingular Universe.,JETP Lett. 33(1981) 532–535

  83. [91]

    Nakajima,On Quantum Theory of Transport Phenomena: Steady Diffusion,Prog

    S. Nakajima,On Quantum Theory of Transport Phenomena: Steady Diffusion,Prog. Theor. Phys.20(1958) 948–959

  84. [92]

    Zwanzig,Ensemble Method in the Theory of Irreversibility,J

    R. Zwanzig,Ensemble Method in the Theory of Irreversibility,J. Chem. Phys.33(1960) 1338

  85. [93]

    M. J. W. Hall, J. D. Cresser, L. Li and E. Andersson,Canonical form of master equations and characterization of non-Markovianity,Phys. Rev. A89(2014) 042120, [1009.0845]

  86. [94]

    Burgess, D

    C. Burgess, D. Dineen, R. Holman and G. Kaplanek,The Compleat Scalar Disent-Angler (to appear),26xx.xxxxx

  87. [95]

    C. H. Fleming and N. I. Cummings,The Accuracy of Perturbative Master Equations,Phys. Rev. E83(2011) 031117, [1010.5025]

  88. [96]

    Kaplanek and C

    G. Kaplanek and C. P. Burgess,Hot Accelerated Qubits: Decoherence, Thermalization, Secular Growth and Reliable Late-time Predictions,JHEP03(2020) 008, [1912.12951]

  89. [97]

    C. P. Burgess and G. Kaplanek,Gravity, Horizons and Open EFTs,2212.09157

  90. [98]

    Lampert, S

    L. Lampert, S. Gadamsetty, S. Chaudhary, Y. Pei, J. Chen, E. Crowder et al.,Sixth-order time-convolutionless master equation and beyond: Late-time resummations, two types of divergences, and the limits of validity,Phys. Rev. A111(2025) 042214

  91. [99]

    N. C. Tsamis and R. P. Woodard,Stochastic quantum gravitational inflation,Nucl. Phys. B724 (2005) 295–328, [gr-qc/0505115]

  92. [100]

    C. P. Burgess, L. Leblond, R. Holman and S. Shandera,Super-Hubble de Sitter Fluctuations and the Dynamical RG,JCAP03(2010) 033, [0912.1608]

  93. [101]

    C. P. Burgess,Quantum gravity in everyday life: General relativity as an effective field theory, Living Rev. Rel.7(2004) 5–56, [gr-qc/0311082]

  94. [102]

    C. P. Burgess, H. M. Lee and M. Trott,Power-counting and the Validity of the Classical Approximation During Inflation,JHEP09(2009) 103, [0902.4465]

  95. [103]

    Adshead, C

    P. Adshead, C. P. Burgess, R. Holman and S. Shandera,Power-counting during single-field slow-roll inflation,JCAP02(2018) 016, [1708.07443]

  96. [104]

    D. J. Mulryne, D. Seery and D. Wesley,Moment transport equations for non-Gaussianity,JCAP 01(2010) 024, [0909.2256]

  97. [105]

    D. J. Mulryne, D. Seery and D. Wesley,Moment transport equations for the primordial curvature perturbation,JCAP04(2011) 030, [1008.3159]

  98. [106]

    D. J. Mulryne,Transporting non-Gaussianity from sub to super-horizon scales,JCAP09(2013) 010, [1302.3842]. – 46 –

  99. [107]

    Werth, L

    D. Werth, L. Pinol and S. Renaux-Petel,Cosmological Flow of Primordial Correlators,Phys. Rev. Lett.133(2024) 141002, [2302.00655]

  100. [108]

    A. A. Starobinsky,Dynamics of Phase Transition in the New Inflationary Universe Scenario and Generation of Perturbations,Phys. Lett.117B(1982) 175–178

  101. [109]

    Hawking,The Development of Irregularities in a Single Bubble Inflationary Universe, Phys.Lett.B115(1982) 295

    S. Hawking,The Development of Irregularities in a Single Bubble Inflationary Universe, Phys.Lett.B115(1982) 295

  102. [110]

    V. F. Mukhanov,Quantum Theory of Gauge Invariant Cosmological Perturbations,Sov. Phys. JETP67(1988) 1297–1302

  103. [111]

    C. P. Burgess,Introduction to Effective Field Theory. Cambridge University Press, 12, 2020, 10.1017/9781139048040

  104. [112]

    C. P. Burgess, R. Holman and G. Tasinato,Open EFTs, IR effects & late-time resummations: systematic corrections in stochastic inflation,JHEP01(2016) 153, [1512.00169]

  105. [113]

    Bunch and P

    T. Bunch and P. Davies,Quantum Field Theory in de Sitter Space: Renormalization by Point Splitting,Proc.Roy.Soc.Lond.A360(1978) 117–134

  106. [114]

    Lesgourgues, D

    J. Lesgourgues, D. Polarski and A. A. Starobinsky,Quantum to classical transition of cosmological perturbations for nonvacuum initial states,Nucl. Phys. B497(1997) 479–510, [gr-qc/9611019]

  107. [115]

    Serafini, F

    A. Serafini, F. Illuminati and S. De Siena,Von Neumann entropy, mutual information and total correlations of Gaussian states,J. Phys. B37(2004) L21, [quant-ph/0307073]

  108. [116]

    Grain and V

    J. Grain and V. Vennin,Canonical transformations and squeezing formalism in cosmology, JCAP02(2020) 022, [1910.01916]

  109. [117]

    Colas, J

    T. Colas, J. Grain and V. Vennin,Four-mode squeezed states: two-field quantum systems and the symplectic groupSp(4,R),Eur. Phys. J. C82(2022) 6, [2104.14942]. – 47 –

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