pith. sign in

arxiv: 2602.12347 · v2 · pith:IEUZIUNQnew · submitted 2026-02-12 · 🌌 astro-ph.CO · gr-qc· hep-ph· hep-th

Sign-Switching Dark Energy: Smooth Transitions with Recent DESI DR2 Observations

Pith reviewed 2026-05-16 05:15 UTC · model grok-4.3

classification 🌌 astro-ph.CO gr-qchep-phhep-th
keywords sign-switching dark energyHubble tensionDESI DR2baryon acoustic oscillationsType Ia supernovaeΛCDM comparisoncosmological expansion
0
0 comments X

The pith

Sign-switching dark energy models reduce the Hubble tension and fit DESI DR2 observations better than standard ΛCDM.

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

The paper examines cosmological models where dark energy changes sign at a specific transition redshift. This change alters the universe's expansion rate in the late universe without needing extra fields or tuned conditions. By analyzing data from Planck CMB, DESI DR2 BAO, and Pantheon+ supernovae with MCMC methods, the models yield a higher Hubble constant and better statistical scores than the standard model. A sympathetic reader would care because this provides a simple way to address the mismatch between early and late universe measurements of the expansion rate.

Core claim

Sign-switching dark energy provides a novel mechanism for modifying the late-time expansion history of the Universe without invoking additional fields or finely tuned initial conditions. In this class of background-level cosmological models, the dark energy contribution changes sign at a transition redshift z†, producing a sharp deviation from standard ΛCDM dynamics. Confronted with Planck 18 CMB, DESI DR2 BAO, and Pantheon+ & SH0ES SN data via MCMC, these models significantly alleviate the Hubble tension and are preferred over ΛCDM by Akaike and Bayesian information criteria.

What carries the argument

The sign switch of the dark energy contribution at transition redshift z†, which allows it to change from positive to negative or vice versa and modify the expansion history.

If this is right

  • The inferred value of the Hubble constant increases, easing the tension with local measurements.
  • Statistical comparison shows the sign-switching models are favored over ΛCDM by AIC and BIC.
  • The approach remains physically economical, requiring no additional fields.
  • Background evolution fits improve with recent BAO data from DESI DR2.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • If the background-only analysis holds, future surveys could test the transition redshift directly through expansion rate measurements.
  • Extending to perturbation level might reveal effects on galaxy clustering or weak lensing that could confirm or rule out the model.
  • Similar sign-switching mechanisms could be explored in other cosmological parameters to address additional tensions.

Load-bearing premise

The perturbations around the sign switch do not spoil the fit or create new tensions with structure-formation data.

What would settle it

A future observation of the growth rate of cosmic structure or a precise local Hubble measurement that falls outside the range allowed by the sign-switching models would falsify the scenario.

Figures

Figures reproduced from arXiv: 2602.12347 by Be\~nat Ibarra-Uriondo, Mariam Bouhmadi-L\'opez.

Figure 1
Figure 1. Figure 1: Two-dimensional posterior distributions for the sign-switching models, using the latest DESI DR2 (BAO) release, Planck18 (CMB) and Pantheon+ & SH0ES (SN) datasets. The contours correspond to the 68% and 95% confidence levels (C.L.). 4. CMB and BAO constraints Data Combination IV includes the CMB and BAO observations introduced in the previous section. This combination provides stronger constraints on the s… view at source ↗
Figure 2
Figure 2. Figure 2: Two-dimensional posterior distributions for the sign-switching models, using the combinations DESI DR2 (BAO) + Planck18 (CMB) and DESI DR2 (BAO) + Planck18 (CMB) + Pantheon+ & SH0ES (SN) datasets. The contours correspond to the 68% and 95% confidence levels (C.L.). rapid, thereby closely mimicking the ΛsCDM behaviour in this case. 5. CMB, BAO and SN constraints Data Combination V incorporates all previousl… view at source ↗
Figure 3
Figure 3. Figure 3: Reconstructed EoS, energy density normalized to the current value, Hubble parameter, deceleration parameter and jerk for the SSCDM models with Planck18 + DESI DR2 + Pantheon+ & SH0ES (left-most column), and with Planck18 + DESI DR2 (central column) and the Planck18 (right-most column). We also plot the reconstructed Hubble rate and energy density normalized to the Planck PR4 values for ΛCDM, for which Ωm0 … view at source ↗
Figure 4
Figure 4. Figure 4: Reconstructed EoS, energy density normalized to the current value, deceleration parameter and jerk for the ECDM model with Planck18 + DESI DR2 + PantheonPlus & SH0ES (left-most column), and with Planck18 + DESI DR2 (central column) and the Planck18 (right-most column). We also plot the reconstructed Hubble rate and energy density normalized to the Planck PR4 values for ΛCDM, for which Ωm0 = 0.315 and H0 = … view at source ↗
read the original abstract

Sign-switching dark energy provides a novel mechanism for modifying the late-time expansion history of the Universe without invoking additional fields or finely tuned initial conditions. In this work, we investigate a class of background--level cosmological models in which the dark energy contribution changes sign at a transition redshift $z_\dagger$, producing a sharp deviation from standard $\Lambda$CDM dynamics. We confront these models with a comprehensive set of cosmological observations, including Planck 18 cosmic microwave background (CMB) measurements, DESI DR2 Baryonic Acoustic Oscillation (BAO) data and the Pantheon+ $\&$ SH0ES Type Ia supernova sample (SN). Using a full Markov Chain Monte Carlo (MCMC) analysis, we find that the sign-switching scenario significantly alleviates the Hubble tension while obtaining better results when statistically comparing with $\Lambda$CDM, as quantified by the Akaike and Bayesian information Criteria. Although the model is explored only at the background level, the improvement in the inferred Hubble constant demonstrates that sign-switching dark energy offers a promising and physically economical pathway toward resolving late-universe discrepancies.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

3 major / 1 minor

Summary. The paper introduces a sign-switching dark energy model in which the dark energy density changes sign at a transition redshift z_†. Using MCMC analysis with Planck 2018 CMB distance priors, DESI DR2 BAO data, and Pantheon+ & SH0ES supernovae, it claims that this model significantly alleviates the Hubble tension and provides better statistical fits than ΛCDM as measured by AIC and BIC.

Significance. If the background-level results hold under full perturbation analysis, the model offers a simple modification to the late-time expansion history that improves the Hubble constant inference without additional fields. The incorporation of recent DESI DR2 data and the quantitative AIC/BIC comparison provide a clear basis for assessing preference over ΛCDM.

major comments (3)
  1. [Model and Results] The transition redshift z_† is a free parameter whose value is determined by the fit to improve the Hubble constant; this makes the reported alleviation of the tension partly by construction rather than an independent prediction (see model definition and results sections).
  2. [Analysis and Discussion] The analysis is performed only at the background level. No check is reported on whether perturbations around the sign switch remain stable or compatible with CMB power spectra and growth data when inserted into a Boltzmann solver; a sign change in ρ_DE generically modifies the perturbation equations (e.g., via sound speed or gravitational slip).
  3. [Abstract and Methods] The abstract and methods provide insufficient details on priors for z_† and the sign-switch amplitude, MCMC convergence diagnostics, or the exact parameterization of the transition, leaving the quantitative support for the central claim only moderately grounded.
minor comments (1)
  1. [Title and Abstract] The title refers to 'Smooth Transitions' while the abstract describes a 'sharp deviation'; clarify the transition form for consistency.

Simulated Author's Rebuttal

3 responses · 0 unresolved

We thank the referee for their detailed and constructive report. We address each major comment below and have made revisions to strengthen the manuscript where possible, while remaining honest about the scope of the current background-level analysis.

read point-by-point responses
  1. Referee: The transition redshift z_† is a free parameter whose value is determined by the fit to improve the Hubble constant; this makes the reported alleviation of the tension partly by construction rather than an independent prediction (see model definition and results sections).

    Authors: We acknowledge that z_† is a free parameter whose posterior is informed by the data. However, the sign-switching model is not an arbitrary construction: it imposes a specific functional form for the dark energy density evolution (a sign change at z_† with a fixed amplitude parameter), and the joint fit to Planck 2018 distance priors, DESI DR2 BAO, and Pantheon+ & SH0ES supernovae must simultaneously satisfy all three datasets. The resulting best-fit z_† emerges naturally from this multi-probe constraint and yields statistically preferred fits (lower AIC/BIC) compared to ΛCDM. We have added a paragraph in the discussion clarifying that the Hubble-constant improvement is a derived consequence of the model's ability to accommodate the observed late-time expansion history, not an imposed outcome. revision: partial

  2. Referee: The analysis is performed only at the background level. No check is reported on whether perturbations around the sign switch remain stable or compatible with CMB power spectra and growth data when inserted into a Boltzmann solver; a sign change in ρ_DE generically modifies the perturbation equations (e.g., via sound speed or gravitational slip).

    Authors: This is a fair and important point. The present work is explicitly limited to background evolution, as stated in the abstract. A complete perturbation analysis would require implementing the sign-switching prescription in a Boltzmann solver to verify stability, sound-speed behavior, and consistency with CMB spectra and growth data. We have expanded the discussion section to explicitly note this limitation, state that perturbations around the transition require separate treatment, and indicate that such an analysis is planned for follow-up work. No claim is made that the background-level results automatically extend to the perturbative regime. revision: partial

  3. Referee: The abstract and methods provide insufficient details on priors for z_† and the sign-switch amplitude, MCMC convergence diagnostics, or the exact parameterization of the transition, leaving the quantitative support for the central claim only moderately grounded.

    Authors: We thank the referee for highlighting this lack of clarity. We have revised the methods section to specify: (i) the exact functional form of the transition (a smooth but rapid switch in ρ_DE controlled by a transition width parameter), (ii) the priors (flat prior on z_† ∈ [0, 3] and on the amplitude parameter), and (iii) MCMC convergence diagnostics (Gelman-Rubin R−1 < 0.01 for all chains). The abstract has been updated with a brief reference to the robustness of the sampling. These additions directly address the concern and strengthen the quantitative grounding of the results. revision: yes

Circularity Check

0 steps flagged

No significant circularity: model parameters fitted via standard MCMC to external data; AIC/BIC penalization keeps comparison independent of inputs

full rationale

The paper defines a background-level sign-switching DE model with free parameters (including transition redshift z†) and performs MCMC fitting to Planck CMB priors, DESI DR2 BAO, and Pantheon+SH0ES data. The reported alleviation of the Hubble tension and improved AIC/BIC scores versus ΛCDM are direct outputs of this fit after standard information-criterion penalization for extra degrees of freedom. No equation reduces to its own input by construction, no fitted parameter is relabeled as an independent prediction, and no load-bearing step relies on self-citation chains or imported uniqueness theorems. The derivation chain is self-contained against the supplied observational datasets and does not exhibit any of the enumerated circularity patterns.

Axiom & Free-Parameter Ledger

2 free parameters · 2 axioms · 1 invented entities

The central claim rests on one new transition parameter fitted to data, standard FLRW background equations, and the assumption that background-only dynamics suffice for the Hubble-tension test.

free parameters (2)
  • transition redshift z_†
    Redshift at which dark energy changes sign; its value is determined by the fit to observations.
  • sign-switch amplitude
    Magnitude of the dark-energy term before and after the transition; fitted to data.
axioms (2)
  • domain assumption Background FLRW expansion history governs the observables used
    Invoked throughout the MCMC analysis of CMB, BAO, and SN distances.
  • ad hoc to paper Perturbations around the sign switch do not alter the background fit appreciably
    Required because the model is studied only at background level.
invented entities (1)
  • sign-switching dark energy no independent evidence
    purpose: To produce a sharp but smooth deviation from ΛCDM expansion without extra fields
    Postulated mechanism whose only support is the improved statistical fit; no independent falsifiable signature is provided.

pith-pipeline@v0.9.0 · 5508 in / 1474 out tokens · 49988 ms · 2026-05-16T05:15:21.548155+00:00 · methodology

discussion (0)

Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.

Lean theorems connected to this paper

Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

What do these tags mean?
matches
The paper's claim is directly supported by a theorem in the formal canon.
supports
The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
extends
The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
uses
The paper appears to rely on the theorem as machinery.
contradicts
The paper's claim conflicts with a theorem or certificate in the canon.
unclear
Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.

Forward citations

Cited by 4 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Signatures of Modified Gravity Below $\mathcal{O}(10)$ Mpc in a Dynamical Dark Energy Background

    astro-ph.CO 2026-05 unverdicted novelty 5.0

    Modified gravity below O(10) Mpc in a CPL dynamical dark energy background is required to suppress structure growth at low redshifts while satisfying CMB constraints from ISW and lensing.

  2. Do equation of state parametrizations of dark energy faithfully capture the dynamics of the late universe?

    astro-ph.CO 2026-04 unverdicted novelty 5.0

    Node-based reconstruction of cosmic expansion prefers stronger deceleration at z≈1.7 than smooth DE EoS parametrizations, isolating z~1.5-2 as a window where the latter may compress localized kinematic features permit...

  3. Exploring the interplay of late-time dynamical dark energy and new physics before recombination

    astro-ph.CO 2026-03 unverdicted novelty 5.0

    Model-independent reconstruction finds 96.7-98.5% probability of phantom crossing if recombination is standard, but early new physics to ease Hubble tension weakens this preference while requiring unrealistically high...

  4. Constraints on Coupled Dark Energy in the DESI Era

    astro-ph.CO 2026-04 unverdicted novelty 4.0

    New cosmological data mildly favor a small coupling between dark matter and a scalar dark energy field at |β| ≈ 0.03 while allowing an effective phantom-crossing equation of state.

Reference graph

Works this paper leans on

124 extracted references · 124 canonical work pages · cited by 4 Pith papers · 48 internal anchors

  1. [1]

    Although BAO data are also sensitive to Ω m, an additional prior is required to fully break the degeneracy between the expansion rate and the sound-horizon scale

    Big Bang Nucleosynthesis (BBN) prior onΩ b0h2 In the absence of an external determination of the sound horizon at the drag epoch,r d, BAO measurements provide an uncalibrated standard ruler and therefore con- strain the combinationH 0 rd, rather thanH 0 andr d sep- arately. Although BAO data are also sensitive to Ω m, an additional prior is required to fu...

  2. [2]

    Baryon Acoustic Oscillations BAO constitute a powerful observational probe for constraining cosmological parameters, particularly when combined with complementary datasets such as the CMB. The characteristic BAO feature imprinted in the matter power spectrum provides measurements of the Hubble expansion rate;H(z), and cosmological distance measures, there...

  3. [3]

    Cosmic Microwave Background The CMB is one of the most powerful observational tools for studying the early Universe, carrying detailed information about cosmological evolution from the epoch of photon decoupling to the present day. Although the full temperature and polarisation power spectra depend on a wide range of physical effects, their sensitivity to...

  4. [4]

    Fitting the models to these data reveals a significant shift in the inferred value ofH 0 relative to ΛCDM

    CMB constraints Combination I consists solely of CMB data. Fitting the models to these data reveals a significant shift in the inferred value ofH 0 relative to ΛCDM. In particular, sign-switching models favour higher values ofH 0, espe- cially in their smooth realisations. The discontinuous models, abrupt Λ sCDM and LΛCDM, favour higher inferred values of...

  5. [5]

    The parametersH 0 and Ω m0 appear to increase across all models relative to ΛCDM, particularly in LΛCDM and SSCDM

    BAO constraints Data Combination II probes the evolution of the BAO measurements. The parametersH 0 and Ω m0 appear to increase across all models relative to ΛCDM, particularly in LΛCDM and SSCDM. Regarding the additional parameters, the models ex- hibit mildly different behaviour. For abrupt Λ sCDM, the transition redshift lies beyond the range currently...

  6. [6]

    SN constraints Data Combination III relies only on SN observations. When fitted to these data, both the Hubble constant H0 and the matter density Ωm0 are similarly constrained across all models, exhibiting nearly identical central val- ues and uncertainties. This dataset alone has limited constraining power on the additional parameters, failing to constra...

  7. [7]

    This combination provides stronger constraints on the sign- switching redshift

    CMB and BAO constraints Data Combination IV includes the CMB and BAO observations introduced in the previous section. This combination provides stronger constraints on the sign- switching redshift. For the Hubble constantH 0 and the matter density Ωm0, all sign-switching models favour slightly higher val- ues than those inferred under ΛCDM. By contrast, t...

  8. [8]

    CMB, BAO and SN constraints Data Combination V incorporates all previously con- sidered datasets, namely CMB, BAO, and SN. When fit- ted to this full dataset, all sign-switching models favour higher inferred values ofH 0 and Ωm0 than ΛCDM, while the baryon density is inferred to be lower, reflecting the impact of the sign-switching behaviour. The transiti...

  9. [9]

    Further discussions Exploring alternative prior choices reveals that, in some cases, the width of the prior significantly impacts the resulting posterior distribution. For the parameter ηin the ECDM model, extending the upper bound of the prior beyondU(0.1,30) removes the preference for slower transition speeds, instead producing a plateau for η≳3.3. In p...

  10. [10]

    The SSCDM model For the SSCDM model, the EoS parameter remains close to−1, exhibiting a significant deviation only dur- ing the sign-switching phase. From the evolution off d(z) andρ d(z)/ρΛ0, we infer that the transition region is rel- atively broad for data Combinations I and IV, becoming significantly more constrained only in Combination V. From the ev...

  11. [11]

    hysteresis type phenomenon

    The ECDM model The ECDM model exhibits a qualitatively similar phe- nomenology to SSCDM, and we therefore refrain from repeating the full discussion. In this case, however, the transition redshift is better constrained, which leads to more clearly defined dynamical features. In particu- lar, the crossing of the deceleration parameter threshold q(z) = 0 ap...

  12. [12]

    A. G. Riesset al.(Supernova Search Team), Observa- tional evidence from supernovae for an accelerating uni- verse and a cosmological constant, Astron. J.116, 1009 17 (1998), arXiv:astro-ph/9805201

  13. [13]

    Perlmutteret al.(Supernova Cosmology Project), Measurements of Ω and Λ from 42 High Redshift Super- novae, Astrophys

    S. Perlmutteret al.(Supernova Cosmology Project), Measurements of Ω and Λ from 42 High Redshift Su- pernovae, Astrophys. J.517, 565 (1999), arXiv:astro- ph/9812133

  14. [14]

    D. J. Eisensteinet al., Detection of the baryon acous- tic peak in the large-scale correlation function of sdss luminous red galaxies, The Astrophysical Journal633, 560 (2005)

  15. [15]

    S. Coleet al., The 2df galaxy redshift survey: Power- spectrum analysis of the final data set and cosmological implications, Monthly Notices of the Royal Astronom- ical Society362, 505 (2005)

  16. [16]

    W. J. Percivalet al., Baryon acoustic oscillations in the sloan digital sky survey data release 7 galaxy sample, Monthly Notices of the Royal Astronomical Society401, 2148 (2010)

  17. [17]

    Tegmarket al., The three-dimensional power spec- trum of galaxies from the sloan digital sky survey, The Astrophysical Journal606, 702 (2004)

    M. Tegmarket al., The three-dimensional power spec- trum of galaxies from the sloan digital sky survey, The Astrophysical Journal606, 702 (2004)

  18. [18]

    B. A. Reidet al., Cosmological constraints from the clustering of the sloan digital sky survey dr7 luminous red galaxies, Monthly Notices of the Royal Astronomical Society404, 60 (2010)

  19. [19]

    C. L. Bennettet al., First-year wilkinson microwave an- isotropy probe (wmap) observations: Preliminary maps and basic results, The Astrophysical Journal Supple- ment Series148, 1 (2003)

  20. [20]

    Komatsuet al., Seven-year wilkinson microwave anisotropy probe (wmap) observations: Cosmological interpretation, The Astrophysical Journal Supplement Series192, 18 (2011)

    E. Komatsuet al., Seven-year wilkinson microwave anisotropy probe (wmap) observations: Cosmological interpretation, The Astrophysical Journal Supplement Series192, 18 (2011)

  21. [21]

    Collaboration, Planck 2013 results

    P. Collaboration, Planck 2013 results. xvi. cosmolo- gical parameters, Astronomy & Astrophysics571, A16 (2014)

  22. [22]

    Planck 2018 results. VI. Cosmological parameters

    N. Aghanimet al.(Planck), Planck 2018 results. VI. Cosmological parameters, Astron. Astrophys.641, A6 (2020), [Erratum: Astron.Astrophys. 652, C4 (2021)], arXiv:1807.06209 [astro-ph.CO]

  23. [23]

    Sanchez-Cidet al.(DES), Dark Energy Survey Year 6 Results: Weak Lensing and Galaxy Clustering Cos- mological Analysis Framework (2026), arXiv:2601.14859 [astro-ph.CO]

    D. Sanchez-Cidet al.(DES), Dark Energy Survey Year 6 Results: Weak Lensing and Galaxy Clustering Cos- mological Analysis Framework (2026), arXiv:2601.14859 [astro-ph.CO]

  24. [24]

    Weinberg, The cosmological constant problem, Rev

    S. Weinberg, The cosmological constant problem, Rev. Mod. Phys.61, 1 (1989)

  25. [25]

    The Case for a Positive Cosmological Lambda-term

    V. Sahni and A. A. Starobinsky, The Case for a positive cosmological Lambda term, Int. J. Mod. Phys. D09, 373 (2000), arXiv:astro-ph/9904398

  26. [26]

    S. M. Carroll, The Cosmological constant, Living Rev. Rel.4, 1 (2001), arXiv:astro-ph/0004075

  27. [27]

    Padmanabhan, Cosmological constant: The Weight of the vacuum, Phys

    T. Padmanabhan, Cosmological constant: The Weight of the vacuum, Phys. Rept.380, 235 (2003), arXiv:hep- th/0212290

  28. [28]

    Ratra and P

    B. Ratra and P. J. E. Peebles, Cosmological con- sequences of a rolling homogeneous scalar field, Phys. Rev. D37, 3406 (1988)

  29. [29]

    Armendariz-Picon, V

    C. Armendariz-Picon, V. Mukhanov, and P. J. Stein- hardt, Essentials of k-essence, Phys. Rev. D63, 103510 (2001)

  30. [30]

    Dark energy from the string axiverse

    M. Kamionkowski, J. Pradler, and D. G. E. Walker, Dark energy from the string axiverse, Phys. Rev. Lett. 113, 251302 (2014), arXiv:1409.0549 [hep-ph]

  31. [31]

    Cosmological tests of an axiverse-inspired quintessence field

    R. Emami, D. Grin, J. Pradler, A. Raccanelli, and M. Kamionkowski, Cosmological tests of an axiverse- inspired quintessence field, Phys. Rev. D93, 123005 (2016), arXiv:1603.04851 [astro-ph.CO]

  32. [32]

    Chiang, C

    H.-W. Chiang, C. G. Boiza, and M. Bouhmadi- L´ opez, Observational constraints on generalised axion- like potentials for the late Universe, JCAP08, 064, arXiv:2503.04898 [astro-ph.CO]

  33. [33]

    A. Y. Kamenshchik, U. Moschella, and V. Pasquier, An Alternative to quintessence, Phys. Lett. B511, 265 (2001), arXiv:gr-qc/0103004

  34. [34]

    T. S. Koivisto and N. J. Nunes, Inflation and dark en- ergy from three-forms, Phys. Rev. D80, 103509 (2009), arXiv:0908.0920 [astro-ph.CO]

  35. [35]

    T. S. Koivisto and N. J. Nunes, Three-form cosmology, Phys. Lett. B685, 105 (2010), arXiv:0907.3883 [astro- ph.CO]

  36. [36]

    Interacting 3-form dark energy models: distinguishing interactions and avoiding the Little Sibling of the Big Rip

    J. Morais, M. Bouhmadi-L´ opez, K. Sravan Kumar, J. Marto, and Y. Tavakoli, Interacting 3-form dark en- ergy models: distinguishing interactions and avoiding the Little Sibling of the Big Rip, Phys. Dark Univ.15, 7 (2017), arXiv:1608.01679 [gr-qc]

  37. [37]

    Cosmic infinity: A dynamical system approach

    M. Bouhmadi-L´ opez, J. Marto, J. Morais, and C. M. Silva, Cosmic infinity: A dynamical system approach, JCAP03, 042, arXiv:1611.03100 [gr-qc]

  38. [38]

    Bouhmadi-López, H.-W

    M. Bouhmadi-L´ opez, H.-W. Chiang, C. G. Boiza, and P. Chen, Observational constraints on 3-forms dark en- ergy (2025), arXiv:2512.09991 [astro-ph.CO]

  39. [39]

    Horndeski theory and beyond: a review

    T. Kobayashi, Horndeski theory and beyond: a review, Rept. Prog. Phys.82, 086901 (2019), arXiv:1901.07183 [gr-qc]

  40. [40]

    Imperfect Dark Energy from Kinetic Gravity Braiding

    C. Deffayet, O. Pujolas, I. Sawicki, and A. Vikman, Imperfect Dark Energy from Kinetic Gravity Braiding, JCAP10, 026, arXiv:1008.0048 [hep-th]

  41. [41]

    The Imperfect Fluid behind Kinetic Gravity Braiding

    O. Pujolas, I. Sawicki, and A. Vikman, The Imperfect Fluid behind Kinetic Gravity Braiding, JHEP11, 156, arXiv:1103.5360 [hep-th]

  42. [42]

    Borislavov Vasilev, M

    T. Borislavov Vasilev, M. Bouhmadi-L´ opez, and P. Mart´ ın-Moruno, Phantom attractors in kinetic grav- ity braiding theories: a dynamical system approach, JCAP06, 026, arXiv:2212.02547 [gr-qc]

  43. [43]

    Borislavov Vasilev, M

    T. Borislavov Vasilev, M. Bouhmadi-L´ opez, and P. Mart´ ın-Moruno, Dark energy with a shift-symmetric scalar field: Obstacles, loophole hunting and dead ends, Phys. Dark Univ.46, 101679 (2024), arXiv:2406.12576 [gr-qc]

  44. [44]

    T. P. Sotiriou and V. Faraoni, f(R) Theories Of Gravity, Rev. Mod. Phys.82, 451 (2010), arXiv:0805.1726 [gr- qc]

  45. [45]

    Extended Theories of Gravity

    S. Capozziello and M. De Laurentis, Extended The- ories of Gravity, Phys. Rept.509, 167 (2011), arXiv:1108.6266 [gr-qc]

  46. [46]

    Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models

    S. Nojiri and S. D. Odintsov, Unified cosmic history in modified gravity: from F(R) theory to Lorentz non-invariant models, Phys. Rept.505, 59 (2011), arXiv:1011.0544 [gr-qc]

  47. [47]

    Modified Gravity Theories on a Nutshell: Inflation, Bounce and Late-time Evolution

    S. Nojiri, S. D. Odintsov, and V. K. Oikonomou, Mod- ified Gravity Theories on a Nutshell: Inflation, Bounce and Late-time Evolution, Phys. Rept.692, 1 (2017), arXiv:1705.11098 [gr-qc]

  48. [48]

    G. R. Bengochea and R. Ferraro, Dark torsion as the cosmic speed-up, Phys. Rev. D79, 124019 (2009), arXiv:0812.1205 [astro-ph]

  49. [49]

    Modified teleparallel gravity: inflation without inflaton

    R. Ferraro and F. Fiorini, Modified teleparallel grav- ity: Inflation without inflaton, Phys. Rev. D75, 084031 (2007), arXiv:gr-qc/0610067. 18

  50. [50]

    Y.-F. Cai, S. Capozziello, M. De Laurentis, and E. N. Saridakis, f(T) teleparallel gravity and cosmology, Rept. Prog. Phys.79, 106901 (2016), arXiv:1511.07586 [gr- qc]

  51. [51]

    Bouhmadi-L´ opez, C

    M. Bouhmadi-L´ opez, C. G. Boiza, M. Petroniko- lou, and E. N. Saridakis, Modified Teleparallelf(T) Gravity, DESI BAO and theH 0 Tension (2026), arXiv:2601.22225 [gr-qc]

  52. [52]

    Teleparallel Palatini theories

    J. Beltr´ an Jim´ enez, L. Heisenberg, and T. S. Koiv- isto, Teleparallel Palatini theories, JCAP08, 039, arXiv:1803.10185 [gr-qc]

  53. [53]

    Beltr´ an Jim´ enez, L

    J. Beltr´ an Jim´ enez, L. Heisenberg, T. S. Koivisto, and S. Pekar, Cosmology inf(Q) geometry, Phys. Rev. D 101, 103507 (2020), arXiv:1906.10027 [gr-qc]

  54. [54]

    Ayuso, R

    I. Ayuso, R. Lazkoz, and V. Salzano, Observational constraints on cosmological solutions off(Q) theor- ies, Phys. Rev. D103, 063505 (2021), arXiv:2012.00046 [astro-ph.CO]

  55. [55]

    C. G. Boiza, M. Petronikolou, M. Bouhmadi-L´ opez, and E. N. Saridakis, Addressing H 0 and S 8 tensions within f(Q) cosmology, JCAP12, 011, arXiv:2505.18264 [astro- ph.CO]

  56. [56]

    Ayuso, M

    I. Ayuso, M. Bouhmadi-L´ opez, C.-Y. Chen, X. Y. Chew, K. Dialektopoulos, and Y. C. Ong, Insights in f(Q) cos- mology: the relevance of the connection, JCAP11, 068, arXiv:2506.03506 [gr-qc]

  57. [57]

    Capozziello, V

    S. Capozziello, V. De Falco, and C. Ferrara, The role of the boundary term in f(Q, B) symmetric tele- parallel gravity, Eur. Phys. J. C83, 915 (2023), arXiv:2307.13280 [gr-qc]

  58. [58]

    De, T.-H

    A. De, T.-H. Loo, and E. N. Saridakis, Non-metricity with boundary terms:f(Q,C) gravity and cosmology, JCAP03, 050, arXiv:2308.00652 [gr-qc]

  59. [59]

    Modified teleparallel theories of gravity

    S. Bahamonde, C. G. B¨ ohmer, and M. Wright, Modified teleparallel theories of gravity, Phys. Rev. D92, 104042 (2015), arXiv:1508.05120 [gr-qc]

  60. [60]

    Bahamonde, K

    S. Bahamonde, K. F. Dialektopoulos, and J. Levi Said, Can Horndeski Theory be recast using Teleparal- lel Gravity?, Phys. Rev. D100, 064018 (2019), arXiv:1904.10791 [gr-qc]

  61. [61]

    Lamaaoune, Exploring the universe expansion his- tory with f(R,T) gravity: Constraints on cosmological parameters, Phys

    M. Lamaaoune, Exploring the universe expansion his- tory with f(R,T) gravity: Constraints on cosmological parameters, Phys. Lett. B873, 140134 (2026)

  62. [62]

    In the Realm of the Hubble tension $-$ a Review of Solutions

    E. Di Valentino, O. Mena, S. Pan, L. Visinelli, W. Yang, A. Melchiorri, D. F. Mota, A. G. Riess, and J. Silk, In the realm of the Hubble tension—a review of solutions, Class. Quant. Grav.38, 153001 (2021), arXiv:2103.01183 [astro-ph.CO]

  63. [63]

    Early Dark Energy Can Resolve The Hubble Tension

    V. Poulin, T. L. Smith, T. Karwal, and M. Kami- onkowski, Early Dark Energy Can Resolve The Hubble Tension, Phys. Rev. Lett.122, 221301 (2019), arXiv:1811.04083 [astro-ph.CO]

  64. [64]

    The Hubble Tension and Early Dark Energy

    M. Kamionkowski and A. G. Riess, The Hubble Tension and Early Dark Energy, Ann. Rev. Nucl. Part. Sci.73, 153 (2023), arXiv:2211.04492 [astro-ph.CO]

  65. [65]

    E. Di Valentino, Cracks in the Standard Cosmological Model: Anomalies, Tensions, and Hints of New Physics, in3rd General Meeting of the COST Action: Cosmic WISPers (CA21106)(2026) arXiv:2601.01525 [astro- ph.CO]

  66. [66]

    A. G. Riess, S. Casertano, W. Yuan, J. B. Bowers, L. Macri, J. C. Zinn, and D. Scolnic, Cosmic Distances Calibrated to 1% Precision with Gaia EDR3 Parallaxes and Hubble Space Telescope Photometry of 75 Milky Way Cepheids Confirm Tension with ΛCDM, Astro- phys. J. Lett.908, L6 (2021), arXiv:2012.08534 [astro- ph.CO]

  67. [67]

    The Pantheon+ Analysis: Cosmological Constraints

    D. Broutet al., The Pantheon+ Analysis: Cosmo- logical Constraints, Astrophys. J.938, 110 (2022), arXiv:2202.04077 [astro-ph.CO]

  68. [68]

    DESI DR2 Results II: Measurements of Baryon Acoustic Oscillations and Cosmological Constraints

    M. Abdul Karimet al.(DESI), DESI DR2 results. II. Measurements of baryon acoustic oscillations and cos- mological constraints, Phys. Rev. D112, 083515 (2025), arXiv:2503.14738 [astro-ph.CO]

  69. [69]

    Akarsu, J

    O. Akarsu, J. D. Barrow, L. A. Escamilla, and J. A. Vazquez, Graduated dark energy: Observational hints of a spontaneous sign switch in the cosmo- logical constant, Phys. Rev. D101, 063528 (2020), arXiv:1912.08751 [astro-ph.CO]

  70. [70]

    Acquaviva, Ö

    G. Acquaviva, O. Akarsu, N. Katirci, and J. A. Vazquez, Simple-graduated dark energy and spatial curvature, Phys. Rev. D104, 023505 (2021), arXiv:2104.02623 [astro-ph.CO]

  71. [71]

    Akarsu, S

    O. Akarsu, S. Kumar, E. ¨Oz¨ ulker, and J. A. Vazquez, Relaxing cosmological tensions with a sign switch- ing cosmological constant, Phys. Rev. D104, 123512 (2021), arXiv:2108.09239 [astro-ph.CO]

  72. [72]

    Akarsu, S

    O. Akarsu, S. Kumar, E. ¨Oz¨ ulker, J. A. Vazquez, and A. Yadav, Relaxing cosmological tensions with a sign switching cosmological constant: Improved results with Planck, BAO, and Pantheon data, Phys. Rev. D108, 023513 (2023), arXiv:2211.05742 [astro-ph.CO]

  73. [73]

    Akarsu, E

    O. Akarsu, E. Di Valentino, S. Kumar, R. C. Nunes, J. A. Vazquez, and A. Yadav, ΛsCDM model: A prom- ising scenario for alleviation of cosmological tensions (2023), arXiv:2307.10899 [astro-ph.CO]

  74. [74]

    E. A. Paraskevas, A. Cam, L. Perivolaropoulos, and O. Akarsu, Transition dynamics in the ΛsCDM model: Implications for bound cosmic structures, Phys. Rev. D 109, 103522 (2024), arXiv:2402.05908 [astro-ph.CO]

  75. [75]

    $\Lambda_{\rm s}$CDM cosmology from a type-II minimally modified gravity

    O. Akarsu, A. De Felice, E. Di Valentino, S. Kumar, R. C. Nunes, E. Ozulker, J. A. Vazquez, and A. Yadav, ΛsCDM cosmology from a type-II minimally modified gravity (2024), arXiv:2402.07716 [astro-ph.CO]

  76. [76]

    Akarsu, A

    O. Akarsu, A. De Felice, E. Di Valentino, S. Kumar, R. C. Nunes, E. ¨Oz¨ ulker, J. A. Vazquez, and A. Ya- dav, Cosmological constraints on ΛsCDM scenario in a type II minimally modified gravity, Phys. Rev. D110, 103527 (2024), arXiv:2406.07526 [astro-ph.CO]

  77. [77]

    Akarsu, B

    O. Akarsu, B. Bulduk, A. De Felice, N. Katırcı, and N. M. Uzun, Unexplored regions in teleparallel f(T) gravity: Sign-changing dark energy density, Phys. Rev. D112, 083532 (2025), arXiv:2410.23068 [gr-qc]

  78. [78]

    M. S. Souza, A. M. Barcelos, R. C. Nunes, O. Akarsu, and S. Kumar, Mapping the Λ sCDM Scenario to f(T) Modified Gravity: Effects on Structure Growth Rate, Universe11, 2 (2025), arXiv:2501.18031 [astro-ph.CO]

  79. [79]

    Akarsu, L

    O. Akarsu, L. Perivolaropoulos, A. Tsikoundoura, A. E. Y¨ ukselci, and A. Zhuk, Dynamical dark energy with AdS-to-dS and dS-to-dS transitions: Implications for theH 0 tension (2025), arXiv:2502.14667 [astro-ph.CO]

  80. [80]

    Akarsu, A

    ¨O. Akarsu, A. C ¸ am, E. A. Paraskevas, and L. Pe- rivolaropoulos, Linear matter density perturbations in the Λ sCDM model: Examining growth dynam- ics and addressing the S 8 tension, JCAP08, 089, arXiv:2502.20384 [astro-ph.CO]. 19

Showing first 80 references.