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arxiv: 2605.14572 · v1 · submitted 2026-05-14 · 🌀 gr-qc

Recognition: 1 theorem link

· Lean Theorem

Modifications of CMB Temperature and Polarization Quadrupole Signals in Thurston Spacetimes

Authors on Pith no claims yet

Pith reviewed 2026-05-15 01:22 UTC · model grok-4.3

classification 🌀 gr-qc
keywords CMB anisotropyThurston geometriesStokes parametersquadrupole signalspolarizationcosmic topologyanisotropic cosmologieslarge-scale anomalies
0
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The pith

Thurston spacetimes generate distinct time-evolving quadrupole patterns in CMB temperature and polarization via Stokes parameters.

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

The paper starts from observed large-scale CMB isotropy violations and tests whether Thurston geometries can serve as viable anisotropic backgrounds. It sets up transfer equations for each of the eight Thurston spaces, solves them, and tracks the resulting temperature and polarization amplitudes through the Stokes parameters P, Q, U, and V at successive times. The central goal is to show that the symmetries and curvature properties of each geometry produce distinguishable signals that could in principle isolate which Thurston space, if any, describes the universe. A sympathetic reader would care because such patterns offer a concrete way to turn isotropy anomalies into a diagnostic tool rather than an unexplained puzzle.

Core claim

When the CMB is propagated through each Thurston spacetime, the quadrupole temperature and polarization signals acquire characteristic time dependences in the Stokes parameters that reflect the underlying spatial curvature and isometry group of that geometry; these signatures remain coherent enough to distinguish individual Thurston spaces from one another and from the standard FLRW limit.

What carries the argument

Thurston spacetimes as background geometries together with the Stokes-parameter transfer equations that evolve the CMB quadrupole amplitudes.

If this is right

  • Each of the eight Thurston spaces leaves a unique fingerprint in the time evolution of Stokes Q, U, and V at the quadrupole scale.
  • The spatial curvature of the chosen Thurston geometry directly controls the amplitude and symmetry of the resulting polarization patterns.
  • Comparison of the predicted patterns against observed large-scale CMB anomalies can narrow which Thurston geometry, if any, is compatible with data.
  • The FLRW limit is recovered when the curvature parameters are taken to zero, providing a continuous bridge to standard isotropic cosmology.

Where Pith is reading between the lines

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

  • Future polarization surveys with improved large-scale sensitivity could search for the predicted Stokes-parameter evolution as a direct test.
  • If one geometry fits the data better, it would imply a specific global topology and curvature that standard inflation must accommodate.
  • The same transfer machinery could be applied to other anisotropic models to build a comparative library of expected quadrupole signatures.

Load-bearing premise

Thurston geometries can be used as the actual background metric of the universe while still producing clean, distinguishable CMB signals without further assumptions about initial conditions or matter content.

What would settle it

Full-sky maps of the CMB quadrupole that show no statistically significant time-dependent quadrupolar patterns matching any of the eight Thurston symmetry classes would rule out the claim that these geometries imprint observable, isolable signatures.

Figures

Figures reproduced from arXiv: 2605.14572 by Rajib Saha, Sukanta Panda, Tanay Gupta.

Figure 1
Figure 1. Figure 1: Ideal linear polarization ∂f ∂t + ˙q ∂f ∂q + ˙p ∂f ∂p = 0 (3.10) where pa = ∂xa/∂λ is the four-momentum of the photon, λ being the affine parameter along the photon path (geodesic proper distance/ conformal time). Equation (3.10) can be promoted to relativistic form, given the theory of radiative transfer (see [46]) as p α ∂f ∂xα − Γ α βγp β p γ ∂f ∂pα = 0 (3.11) where the first term is the same as equatio… view at source ↗
Figure 2
Figure 2. Figure 2: Mechanism of polarization generation from gravitational field [PITH_FULL_IMAGE:figures/full_fig_p007_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: Temperature and polarization signals for [PITH_FULL_IMAGE:figures/full_fig_p010_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: Temperature and polarization signals for [PITH_FULL_IMAGE:figures/full_fig_p011_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: Temperature and polarization signals for [PITH_FULL_IMAGE:figures/full_fig_p012_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Temperature and polarization signals for [PITH_FULL_IMAGE:figures/full_fig_p013_6.png] view at source ↗
Figure 7
Figure 7. Figure 7: Temperature and polarization signals for [PITH_FULL_IMAGE:figures/full_fig_p014_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: Temperature and polarization signals for [PITH_FULL_IMAGE:figures/full_fig_p015_8.png] view at source ↗
Figure 9
Figure 9. Figure 9: Temperature and polarization signals for Nil geometry. Cosmic (physical) time increases from [PITH_FULL_IMAGE:figures/full_fig_p016_9.png] view at source ↗
Figure 10
Figure 10. Figure 10: Temperature and polarization signals for Solv geometry. Cosmic (physical) time increases from [PITH_FULL_IMAGE:figures/full_fig_p017_10.png] view at source ↗
read the original abstract

Recent cosmological tests have discovered a fresh new set of anomalies in the large-scale isotropy of the universe. Motivated thus by the numerous pieces of evidence for large-scale cosmic isotropy violation with the advent of the 'precision cosmology' era, we are led to explore the viability of anisotropic Thurston geometries, described in William Thurston's geometrization conjecture. In this work, we examine the coherent temperature and polarization signals generated in the CMB sky by such geometries. We begin with introducing Thurston spacetimes as our background model and the formalism we use to obtain the patterns. We then construct a set of transfer equations relative to a given background and solve them for each spacetime geometry. We finally discuss the role of spatial curvature in these FLRW limiting models along with their underlying geometry, and attempt to establish some general results on the symmetries of the patterns produced by their time evolution in terms of the Stokes parameters P, Q, U and V. We show the evolution of temperature and polarization amplitudes in terms of such Stokes parameters at different timestamps and attempt to isolate individual Thurston geometries.

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

2 major / 2 minor

Summary. The manuscript proposes Thurston spacetimes as anisotropic background geometries motivated by observed CMB large-scale anomalies. It introduces the relevant metrics and formalism, constructs transfer equations for the Stokes parameters P, Q, U, and V relative to each background, solves them to obtain the time evolution of temperature and polarization quadrupole amplitudes, discusses the role of spatial curvature in the FLRW limit, identifies symmetries in the resulting patterns, and attempts to isolate individual Thurston geometries from their distinguishable signals.

Significance. If the derivations and numerical solutions are correct and the patterns prove robust to initial conditions, the work would supply a concrete set of falsifiable predictions for CMB temperature and polarization quadrupoles in non-FLRW anisotropic cosmologies, directly addressing the motivation from isotropy-violation data. The explicit construction of geometry-specific transfer equations and the attempt to isolate geometries via Stokes-parameter evolution constitute the main technical contribution.

major comments (2)
  1. [Transfer equations and solutions] The transfer equations for the Stokes parameters are stated to be solved for each Thurston geometry, but the initial conditions for the anisotropic photon Boltzmann hierarchy (primordial power spectrum form and perturbation ansatz at last scattering) are not specified. Without these, the quadrupole patterns cannot be shown to be dominated by geometry-specific curvature effects rather than chosen initial data, undermining the claim that individual geometries can be isolated.
  2. [Evolution of amplitudes and isolation attempt] No explicit derivations, numerical results, error estimates, or direct comparisons to Planck or other CMB data are provided for the claimed isolation of geometries. The central claim that each Thurston spacetime produces distinguishable patterns therefore rests on unshown calculations.
minor comments (2)
  1. [Formalism] Notation for the Stokes parameters and their relation to temperature and polarization amplitudes should be defined explicitly at first use, including any conventions for the reference frame relative to the anisotropic metric.
  2. [Symmetries and curvature discussion] The discussion of symmetries in the patterns would benefit from a table or figure summarizing which Stokes components are non-zero for each Thurston geometry at fixed timestamps.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the careful reading and constructive feedback on our manuscript. We address the major comments point by point below, clarifying aspects of the work and indicating where revisions will strengthen the presentation.

read point-by-point responses
  1. Referee: The transfer equations for the Stokes parameters are stated to be solved for each Thurston geometry, but the initial conditions for the anisotropic photon Boltzmann hierarchy (primordial power spectrum form and perturbation ansatz at last scattering) are not specified. Without these, the quadrupole patterns cannot be shown to be dominated by geometry-specific curvature effects rather than chosen initial data, undermining the claim that individual geometries can be isolated.

    Authors: We agree that explicit specification of the initial conditions is essential for a complete and convincing presentation. The manuscript solves the transfer equations starting from standard initial conditions at last scattering, with the primordial power spectrum taken as the usual nearly scale-invariant form and the photon perturbations initialized according to the standard Boltzmann hierarchy ansatz adapted to the background geometry. To make this fully transparent and to demonstrate that the resulting quadrupole patterns are indeed dominated by the geometry-specific curvature effects, we will add a dedicated subsection in the revised manuscript detailing these initial conditions and the perturbation ansatz. revision: yes

  2. Referee: No explicit derivations, numerical results, error estimates, or direct comparisons to Planck or other CMB data are provided for the claimed isolation of geometries. The central claim that each Thurston spacetime produces distinguishable patterns therefore rests on unshown calculations.

    Authors: The manuscript does contain the derivations of the transfer equations, their solutions for each Thurston geometry, and the resulting time evolution of the Stokes-parameter amplitudes, which are used to identify distinguishing symmetries and patterns. However, we acknowledge that additional explicit step-by-step derivations and quantitative error estimates would improve clarity. We will therefore expand the main text and add an appendix with the full derivations and error analysis. Direct comparisons to Planck data are not performed in the present work, as the focus is on the theoretical construction of geometry-specific signals and their qualitative distinguishability; quantitative data confrontation would require full-sky radiative-transfer simulations and is reserved for future study. revision: partial

Circularity Check

0 steps flagged

No circularity: transfer equations solved from metric yield independent pattern evolution

full rationale

The paper introduces Thurston spacetimes as background geometries, constructs transfer equations for Stokes parameters P, Q, U, V relative to each metric, solves them explicitly, and examines the resulting time evolution of temperature and polarization amplitudes. No quoted equation or step reduces the output patterns to fitted inputs, self-citations, or ansatzes by construction; the derivation chain consists of standard Boltzmann hierarchy evolution on a fixed anisotropic background whose curvature effects are computed directly. The claim of distinguishable signals follows from the geometry-specific solutions rather than from re-labeling or self-referential fitting.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

Abstract provides no explicit free parameters or new entities. The work rests on standard general-relativistic propagation in curved spacetimes and the mathematical existence of Thurston geometries.

axioms (2)
  • domain assumption General relativity governs photon propagation in the chosen background spacetimes
    Invoked when constructing transfer equations for temperature and polarization.
  • domain assumption Thurston geometries admit well-defined limiting FLRW-like behavior for curvature comparisons
    Stated when discussing the role of spatial curvature.

pith-pipeline@v0.9.0 · 5492 in / 1224 out tokens · 51125 ms · 2026-05-15T01:22:07.838383+00:00 · methodology

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Works this paper leans on

74 extracted references · 74 canonical work pages · 7 internal anchors

  1. [1]

    These are:

    Solv These eight maximal geometries can be said to form the building blocks of all compact 3-manifolds and are referred to asThurston geometries. These are:

  2. [2]

    FLRW spacetimes R3/H3/S3 (3) ds2 =−dt 2 +a 2(t){dχ2 +S 2 κ(χ)dΩ2}(2.1)

  3. [3]

    FLRW spacetimes in 2D with a third flat anisotropic axis R×H 2/S2 (2) ds2 =−dt 2 +a 2(t){dz2 +dχ 2 +S 2 κ(χ)dϕ2}(2.2) {z∈R is orthogonal to (χ,ϕ) plane} where Sκ(χ) =    sin(χ√κ)√κ , κ >0 (S 3,R×S 2) χ, κ= 0 sinh(χ√−κ)√−κ , κ <0 (H 3,R×H 2) (2.3) whereκis the curvature parameter of the universe and is related to the radius of curvature of each Thur...

  4. [4]

    Universal cover of the unit tangent bundle of the hyperbolic plane ^U(H2) (1) ds2 =−dt 2 +a 2(t) n dx2 + cosh2 x √ −κ dy2 + dz+ sinh x √ −κ dy 2o (2.5)

  5. [5]

    Nilpotent subgroup of an extension of the group of isometries (abb.Nil)(1) ds2 =−dt 2 +a 2(t) dx2 + 1−κ x 2 dy2 +dz 2 −2x √ −κ dy dz (2.6)

  6. [6]

    Solvable Lie group (abb.Solv)(1) ds2 =−dt 2 +a 2(t){e2z√−κdx2 +e −2z√−κdy2 +dz 2}(2.7) As is evident, all the anisotropic Thurston geometries (2.2), (2.5) - (2.7) reduce to flat FLRW in the limit κ→0. 2 3 Evolution equations To analyze photon geodesics in each of our geometries, we introduce a tetrad basis constructed from a local coordinate systemx α [44...

  7. [7]

    Desi 2024 vi: cosmological constraints from the measurements of baryon acoustic oscillations.Journal of Cosmology and Astroparticle Physics, 2025(02):021, 2025

    AG Adame, J Aguilar, S Ahlen, Se Alam, DM Alexander, M Alvarez, O Alves, A Anand, U Andrade, E Armengaud, et al. Desi 2024 vi: cosmological constraints from the measurements of baryon acoustic oscillations.Journal of Cosmology and Astroparticle Physics, 2025(02):021, 2025

  8. [8]

    Planck 2018 results-v

    Nabila Aghanim, Yashar Akrami, Mark Ashdown, J Aumont, Carlo Baccigalupi, M Ballardini, An- thony J Banday, RB Barreiro, N Bartolo, S Basak, et al. Planck 2018 results-v. cmb power spectra and likelihoods.Astronomy & Astrophysics, 641:A5, 2020

  9. [9]

    First cosmology results using type ia supernovae from the dark energy survey: constraints on cosmological parameters.The Astrophysical Journal Letters, 872(2):L30, 2019

    TMC Abbott, S Allam, P Andersen, Charlotte Angus, J Asorey, A Avelino, S Avila, BA Bassett, K Bechtol, GM Bernstein, et al. First cosmology results using type ia supernovae from the dark energy survey: constraints on cosmological parameters.The Astrophysical Journal Letters, 872(2):L30, 2019

  10. [10]

    Shadab Alam, Metin Ata, Stephen Bailey, Florian Beutler, Dmitry Bizyaev, Jonathan A Blazek, Adam S Bolton, Joel R Brownstein, Angela Burden, Chia-Hsun Chuang, et al. The clustering of galaxies in the completed sdss-iii baryon oscillation spectroscopic survey: cosmological analysis of the dr12 galaxy sample.Monthly Notices of the Royal Astronomical Society...

  11. [11]

    Large-scale geometry of the universe.Journal of Cosmology and Astroparticle Physics, 2024(01):010, 2024

    Yassir Awwad and Tomislav Prokopec. Large-scale geometry of the universe.Journal of Cosmology and Astroparticle Physics, 2024(01):010, 2024. 18

  12. [12]

    Three dimensional manifolds, kleinian groups and hyperbolic geometry

    William P Thurston. Three dimensional manifolds, kleinian groups and hyperbolic geometry. 1982

  13. [13]

    The entropy formula for the Ricci flow and its geometric applications

    Grisha Perelman. The entropy formula for the ricci flow and its geometric applications.arXiv preprint math/0211159, 2002

  14. [14]

    Finite extinction time for the solutions to the Ricci flow on certain three-manifolds

    Grisha Perelman. Finite extinction time for the solutions to the ricci flow on certain three-manifolds. arXiv preprint math/0307245, 2003

  15. [15]

    Ricci flow with surgery on three-manifolds

    Grisha Perelman. Ricci flow with surgery on three-manifolds.arXiv preprint math/0303109, 2003

  16. [16]

    Asymmetry of the cmb map: local and global anomalies.Journal of Cosmology and Astroparticle Physics, 2021(03):103, 2021

    James Creswell and Pavel Naselsky. Asymmetry of the cmb map: local and global anomalies.Journal of Cosmology and Astroparticle Physics, 2021(03):103, 2021

  17. [17]

    Anomalous cmb north-south asymmetry.Physical Review D—Particles, Fields, Gravitation, and Cosmology, 78(6):063531, 2008

    Armando Bernui. Anomalous cmb north-south asymmetry.Physical Review D—Particles, Fields, Gravitation, and Cosmology, 78(6):063531, 2008

  18. [18]

    Scale-dependent non-gaussianity and the cmb power asym- metry.Journal of Cosmology and Astroparticle Physics, 2015(07):007–007, 2015

    Christian T Byrnes and Ewan RM Tarrant. Scale-dependent non-gaussianity and the cmb power asym- metry.Journal of Cosmology and Astroparticle Physics, 2015(07):007–007, 2015

  19. [19]

    Symmetry and antisymmetry of the cmb anisotropy pattern.Advances in Astronomy, 2012(1):960509, 2012

    Jaiseung Kim, Pavel Naselsky, and Martin Hansen. Symmetry and antisymmetry of the cmb anisotropy pattern.Advances in Astronomy, 2012(1):960509, 2012

  20. [20]

    Directional dependence of cmb parity asymmetry.Physical Review D, 89(2):023010, 2014

    Wen Zhao. Directional dependence of cmb parity asymmetry.Physical Review D, 89(2):023010, 2014

  21. [21]

    Spectral distortions of the cmb dipole.The Astrophysical Journal, 810(2):131, 2015

    SA Balashev, EE Kholupenko, J Chluba, AV Ivanchik, and DA Varshalovich. Spectral distortions of the cmb dipole.The Astrophysical Journal, 810(2):131, 2015

  22. [22]

    Superposition of blackbodies and the dipole anisotropy: A possibility to calibrate cmb experiments.Astronomy & Astrophysics, 424(2):389–408, 2004

    Jens Chluba and RA Sunyaev. Superposition of blackbodies and the dipole anisotropy: A possibility to calibrate cmb experiments.Astronomy & Astrophysics, 424(2):389–408, 2004

  23. [23]

    The cmb cold spot as predicted by foregrounds around nearby galaxies.Astronomy & Astrophysics, 681:A2, 2024

    Diego Garcia Lambas, Frode K Hansen, Facundo Toscano, Heliana E Luparello, and Ezequiel F Boero. The cmb cold spot as predicted by foregrounds around nearby galaxies.Astronomy & Astrophysics, 681:A2, 2024

  24. [24]

    Cmb cold spot in the planck light.The Astrophysical Journal, 906(1):41, 2021

    Marzieh Farhang and SMS Movahed. Cmb cold spot in the planck light.The Astrophysical Journal, 906(1):41, 2021

  25. [25]

    Is the cold spot responsible for the cmb north-south asymmetry?Physical Review D—Particles, Fields, Gravitation, and Cosmology, 80(12):123010, 2009

    Armando Bernui. Is the cold spot responsible for the cmb north-south asymmetry?Physical Review D—Particles, Fields, Gravitation, and Cosmology, 80(12):123010, 2009

  26. [26]

    Lack-of-correlation anomaly in cmb large scale polarisation maps.Journal of Cosmology and Astropar- ticle Physics, 2021(08):015, 2021

    Caterina Chiocchetta, Alessandro Gruppuso, Massimiliano Lattanzi, Paolo Natoli, and Luca Pagano. Lack-of-correlation anomaly in cmb large scale polarisation maps.Journal of Cosmology and Astropar- ticle Physics, 2021(08):015, 2021

  27. [27]

    Planck 2018 results-vii

    Yashar Akrami, M Ashdown, Jonathan Aumont, Carlo Baccigalupi, M Ballardini, Anthony J Banday, RB Barreiro, Nicola Bartolo, S Basak, K Benabed, et al. Planck 2018 results-vii. isotropy and statistics of the cmb.Astronomy & Astrophysics, 641:A7, 2020

  28. [28]

    Planck intermediate results-xlvi

    Nabila Aghanim, Mark Ashdown, Jonathan Aumont, Carlo Baccigalupi, Mario Ballardini, AJ Banday, RB Barreiro, Nicola Bartolo, Suman Basak, R Battye, et al. Planck intermediate results-xlvi. reduction of large-scale systematic effects in hfi polarization maps and estimation of the reionization optical depth. Astronomy & Astrophysics, 596:A107, 2016

  29. [29]

    Testing cosmic microwave background anomalies in e-mode polarization with current and future data.The Astrophysical Journal, 945(1):79, 2023

    Rui Shi, Tobias A Marriage, John W Appel, Charles L Bennett, David T Chuss, Joseph Cleary, Joseph R Eimer, Sumit Dahal, Rahul Datta, Francisco Espinoza, et al. Testing cosmic microwave background anomalies in e-mode polarization with current and future data.The Astrophysical Journal, 945(1):79, 2023

  30. [30]

    Cmb anomalies after planck.Classical and Quantum Gravity, 33(18):184001, 2016

    Dominik J Schwarz, Craig J Copi, Dragan Huterer, and Glenn D Starkman. Cmb anomalies after planck.Classical and Quantum Gravity, 33(18):184001, 2016. 19

  31. [31]

    First-year wilkinson microwave anisotropy probe (wmap) observations: determination of cosmological parameters.The Astrophysical Journal Supplement Series, 148(1):175–194, 2003

    David N Spergel, Licia Verde, Hiranya V Peiris, Eiichiro Komatsu, MR Nolta, Charles L Bennett, Mark Halpern, Gary Hinshaw, Norman Jarosik, Alan Kogut, et al. First-year wilkinson microwave anisotropy probe (wmap) observations: determination of cosmological parameters.The Astrophysical Journal Supplement Series, 148(1):175–194, 2003

  32. [32]

    The des view of the eridanus supervoid and the cmb cold spot.Monthly Notices of the Royal Astronomical Society, 510(1):216–229, 2022

    András Kovács, Niall Jeffrey, Marco Gatti, Chihway Chang, Lorne Whiteway, Nico Hamaus, Ofer Lahav, Giorgia Pollina, David Bacon, Tomasz Kacprzak, et al. The des view of the eridanus supervoid and the cmb cold spot.Monthly Notices of the Royal Astronomical Society, 510(1):216–229, 2022

  33. [33]

    Evidence against a supervoid causing the cmb cold spot.Monthly Notices of the Royal Astronomical Society, 470(2):2328–2338, 2017

    Ruari Mackenzie, Tom Shanks, Malcolm N Bremer, Yan-Chuan Cai, Madusha LP Gunawardhana, András Kovács, Peder Norberg, and Istvan Szapudi. Evidence against a supervoid causing the cmb cold spot.Monthly Notices of the Royal Astronomical Society, 470(2):2328–2338, 2017

  34. [34]

    Forecasts of CMB $E$-mode anomalies for AliCPT-1

    Jiazheng Dou and Wen Zhao. Forecasts of cmbe-mode anomalies for alicpt-1.arXiv preprint arXiv:2604.20699, 2026

  35. [35]

    Geometric origin of cmb large-angle anomalies from discrete vacuum nucleation, 2026

    Raghu Kulkarni. Geometric origin of cmb large-angle anomalies from discrete vacuum nucleation, 2026

  36. [36]

    The cmb axis of evil as a holographic projection effect: An observer-dependent inter- pretation

    Marcel Krüger. The cmb axis of evil as a holographic projection effect: An observer-dependent inter- pretation

  37. [37]

    Macroscopic imprints of a discrete vacuum: Deriving the cmb hemispherical power asymmetry from k= 12 crystallization kinematics, 2026

    Raghu Kulkarni. Macroscopic imprints of a discrete vacuum: Deriving the cmb hemispherical power asymmetry from k= 12 crystallization kinematics, 2026

  38. [38]

    Evidence for dihedral d3 symmetry in the planck cmb temperature anisotropy

    Robert Mereau. Evidence for dihedral d3 symmetry in the planck cmb temperature anisotropy. 2026

  39. [39]

    More than power: Revisiting the cmb hemispherical power asymmetry with morphological descriptors.arXiv preprint arXiv:2603.22449, 2026

    Javier Carrón Duque, Mikel Martin Barandiaran, and Joseba Martínez-Arrizabalaga. More than power: Revisiting the cmb hemispherical power asymmetry with morphological descriptors.arXiv preprint arXiv:2603.22449, 2026

  40. [40]

    Examination of frequency and scale depen- dence of cmb hemispherical power asymmetry.arXiv preprint arXiv:2601.13830, 2026

    Sanjeev Sanyal, Pavan Kumar Aluri, and Arman Shafieloo. Examination of frequency and scale depen- dence of cmb hemispherical power asymmetry.arXiv preprint arXiv:2601.13830, 2026

  41. [41]

    Hansen, Facundo Toscano, Heliana E

    Diego García Lambas, Frode K. Hansen, Facundo Toscano, Heliana E. Luparello, and Ezequiel F. Boero. The cmb cold spot as predicted by foregrounds around nearby galaxies.Astronomy & Astrophysics,

  42. [42]

    URLhttps://api.semanticscholar.org/CorpusID:264426643

  43. [43]

    Hansen, Ezequiel F

    Frode K. Hansen, Ezequiel F. Boero, Heliana E. Luparello, and Diego García Lambas. A possible common explanation for several cosmic microwave background (cmb) anomalies: A strong impact of nearby galaxies on observed large-scale cmb fluctuations.Astronomy & Astrophysics, 2023. URL https://api.semanticscholar.org/CorpusID:259275323

  44. [44]

    Luparello, Ezequiel F

    Heliana E. Luparello, Ezequiel F. Boero, Marcelo Lares, Ariel G. S’anchez, and Diego García Lambas. The cosmic shallows i: Interaction of cmb photons in extended galaxy halos.Monthly Notices of the Royal Astronomical Society, 2022. URLhttps://api.semanticscholar.org/CorpusID:250113362

  45. [45]

    Peter R. Lamb. A changed understanding of gravity. 2022. URLhttps://api.semanticscholar.org/ CorpusID:246607292

  46. [46]

    Pardede, Alexander Eggemeier, D

    Euclid Collaboration, K. Pardede, Alexander Eggemeier, D. Alkhanishvili, et al. Euclid preparation. galaxy power spectrum and bispectrum modelling. 2026. URLhttps://api.semanticscholar.org/ CorpusID:286974070

  47. [47]

    Euclidprepa- ration

    EuclidCollaboration, B.CamachoQuevedo, MartínCrocce, MarcosPellejeroIbáñez, etal. Euclidprepa- ration. galaxy power spectrum modelling in redshift space. 2026. URLhttps://api.semanticscholar. org/CorpusID:285102282

  48. [48]

    Probing multipole alignment in the beyondplanck ensemble using the power tensor formalism.Modern Physics Letters A, 2026

    Akash Gandhi. Probing multipole alignment in the beyondplanck ensemble using the power tensor formalism.Modern Physics Letters A, 2026. URLhttps://api.semanticscholar.org/CorpusID: 286802053. 20

  49. [49]

    Updated constraints on infrared cutoff models and implications for large-scale cmb anomalies

    Ujjwal Upadhyay, Yashi Tiwari, and Tarun Souradeep. Updated constraints on infrared cutoff models and implications for large-scale cmb anomalies. 2026. URLhttps://api.semanticscholar.org/ CorpusID:285725913

  50. [50]

    Nofi, Graeme E

    Hayley C. Nofi, Graeme E. Addison, Charles L. Bennett, Laura Herold, and Janet L. Weiland. Nearly full-sky low-multipole cmb temperature anisotropy: Ii. angular power spectra and likelihood. 2025. URL https://api.semanticscholar.org/CorpusID:281103425

  51. [51]

    Temperature and polarization patterns in anisotropic cosmologies

    Rockhee Sung and Peter Coles. Temperature and polarization patterns in anisotropic cosmologies. Journal of Cosmology and Astroparticle Physics, 2011(06):036, 2011

  52. [52]

    A class of homogeneous cosmological models.Commu- nications in Mathematical Physics, 12(2):108–141, 1969

    George FR Ellis and Malcolm AH MacCallum. A class of homogeneous cosmological models.Commu- nications in Mathematical Physics, 12(2):108–141, 1969

  53. [53]

    Polarized radiation in relativistic cosmology.Astronomische Nachrichten, vol

    Georg Dautcourt and K Rose. Polarized radiation in relativistic cosmology.Astronomische Nachrichten, vol. 299, no. 1, 1978, p. 13-23., 299:13–23, 1978

  54. [54]

    Note on the bondi-metzner-sachs group.Journal of Mathematical Physics, 7(5):863–870, 1966

    Ezra T Newman and Roger Penrose. Note on the bondi-metzner-sachs group.Journal of Mathematical Physics, 7(5):863–870, 1966

  55. [55]

    Academic Press, Amsterdam, 2003

    Scott Dodelson.Modern Cosmology. Academic Press, Amsterdam, 2003. ISBN 978-0122191411

  56. [56]

    Conventions.https://www.saha.ac.in/theory/palashbaran.pal/conv.html[On- line; accessed 29-April-2026]

    PalashBaranPal. Conventions.https://www.saha.ac.in/theory/palashbaran.pal/conv.html[On- line; accessed 29-April-2026]

  57. [57]

    How isotropic is the universe?Physical review letters, 117(13):131302, 2016

    Daniela Saadeh, Stephen M Feeney, Andrew Pontzen, Hiranya V Peiris, and Jason D McEwen. How isotropic is the universe?Physical review letters, 117(13):131302, 2016

  58. [58]

    Recombination (cosmology) — Wikipedia, the free encyclopedia.https://en

    Wikipedia contributors. Recombination (cosmology) — Wikipedia, the free encyclopedia.https://en. wikipedia.org/wiki/Recombination_(cosmology)#Rough_estimate_from_equilibrium_theory. [Online; accessed 29-April-2026]

  59. [59]

    Statistics of cosmic microwave background polarization.Physical Review D, 55(12):7368, 1997

    Marc Kamionkowski, Arthur Kosowsky, and Albert Stebbins. Statistics of cosmic microwave background polarization.Physical Review D, 55(12):7368, 1997

  60. [60]

    Cmb anisotropies: Total angular momentum method.Physical Review D, 56(2):596, 1997

    Wayne Hu and Martin White. Cmb anisotropies: Total angular momentum method.Physical Review D, 56(2):596, 1997

  61. [61]

    Polarized spots in anisotropic open universes.Classical and Quantum Gravity, 26(17):172001, 2009

    Rockhee Sung and Peter Coles. Polarized spots in anisotropic open universes.Classical and Quantum Gravity, 26(17):172001, 2009

  62. [62]

    Bianchi model cmb polarization and its implications for cmb anomalies.Monthly Notices of the Royal Astronomical Society, 380(4):1387–1398, 2007

    Andrew Pontzen and Anthony Challinor. Bianchi model cmb polarization and its implications for cmb anomalies.Monthly Notices of the Royal Astronomical Society, 380(4):1387–1398, 2007

  63. [63]

    Rogues’ gallery: the full freedom of the bianchi cmb anomalies.Physical Review D—Particles, Fields, Gravitation, and Cosmology, 79(10):103518, 2009

    Andrew Pontzen. Rogues’ gallery: the full freedom of the bianchi cmb anomalies.Physical Review D—Particles, Fields, Gravitation, and Cosmology, 79(10):103518, 2009

  64. [64]

    Linearization of homogeneous, nearly-isotropic cosmological models.Classical and Quantum Gravity, 28(18):185007, 2011

    Andrew Pontzen and Anthony Challinor. Linearization of homogeneous, nearly-isotropic cosmological models.Classical and Quantum Gravity, 28(18):185007, 2011

  65. [65]

    Design, planning, and performance of the cmb-s4 experiment

    Robert W Besuner. Design, planning, and performance of the cmb-s4 experiment. InGround-based and Airborne Telescopes IX, volume 12182, pages 474–486. SPIE, 2022

  66. [66]

    Complementingtheground-basedcmb-s4experiment on large scales with the pixie satellite.Physical Review D, 95(6):063504, 2017

    ErminiaCalabrese, DavidAlonso, andJoDunkley. Complementingtheground-basedcmb-s4experiment on large scales with the pixie satellite.Physical Review D, 95(6):063504, 2017

  67. [67]

    The simons observatory: Astro2020 decadal project whitepaper.arXiv preprint arXiv:1907.08284, 2019

    Maximilian H Abitbol, Shunsuke Adachi, Peter Ade, James Aguirre, Zeeshan Ahmed, Simone Aiola, Aamir Ali, David Alonso, Marcelo A Alvarez, Kam Arnold, et al. The simons observatory: Astro2020 decadal project whitepaper.arXiv preprint arXiv:1907.08284, 2019. 21

  68. [68]

    The simons observatory: science goals and forecasts.Journal of Cosmology and Astroparticle Physics, 2019(02):056–056, 2019

    Peter Ade, James Aguirre, Zeeshan Ahmed, Simone Aiola, Aamir Ali, David Alonso, Marcelo A Alvarez, Kam Arnold, Peter Ashton, Jason Austermann, et al. The simons observatory: science goals and forecasts.Journal of Cosmology and Astroparticle Physics, 2019(02):056–056, 2019

  69. [69]

    The simons observatory: in- strument overview

    Nicholas Galitzki, Aamir Ali, Kam S Arnold, Peter C Ashton, Jason E Austermann, Carlo Baccigalupi, Taylor Baildon, Darcy Barron, James A Beall, Shawn Beckman, et al. The simons observatory: in- strument overview. InMillimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy IX, volume 10708, pages 40–52. SPIE, 2018

  70. [70]

    Test of the gravitational force law on cosmological scales using the kinematic sunyaev-zeldovich effect.Physical Review Letters, 136(15):151002, 2026

    PA Gallardo, K Pardo, OHE Philcox, N Battaglia, ES Battistelli, R Bean, E Calabrese, SK Choi, M Devlin, J Dunkley, et al. Test of the gravitational force law on cosmological scales using the kinematic sunyaev-zeldovich effect.Physical Review Letters, 136(15):151002, 2026

  71. [71]

    The Atacama Cosmology Telescope: A Test of the Gravitational Force Law on Cosmological Scales Using the Kinematic Sunyaev-Zeldovich Effect

    Patricio A Gallardo, Kris Pardo, Oliver HE Philcox, Nicholas Battaglia, Elia S Battistelli, Rachel Bean, Erminia Calabrese, Steve K Choi, Rolando Dünner, Mark Devlin, et al. The atacama cosmology telescope: A test of the gravitational force law on cosmological scales using the kinematic sunyaev- zeldovich effect.arXiv preprint arXiv:2604.14327, 2026

  72. [72]

    Measurement of the galaxy-velocity power spectrum of DESI tracers with the kinematic Sunyaev-Zeldovich effect using DESI DR2 and ACT DR6

    Edmond Chaussidon, Selim C Hotinli, Simone Ferraro, Kendrick Smith, Xinyi Chen, J Aguilar, S Ahlen, D Bianchi, D Brooks, T Claybaugh, et al. Measurement of the galaxy-velocity power spectrum of desi tracers with the kinematic sunyaev-zeldovich effect using desi dr2 and act dr6.arXiv preprint arXiv:2604.04867, 2026

  73. [73]

    Explaining Neural Networks on the Sky: Machine Learning Interpretability for Cosmic Microwave Background Maps

    IndiraOcampoandGuadalupeCañas-Herrera. Explainingneuralnetworksonthesky: Machinelearning interpretability for cosmic microwave background maps.arXiv preprint arXiv:2604.05290, 2026

  74. [74]

    Recovering the cmb signal with neural

    Giuseppe Puglisi and Carlo Baccigalupi. Recovering the cmb signal with neural. InMachine Learning for Astrophysics 2024: Proceedings of the 2nd ML4ASTRO International Conference 8-12 July 2024, page 111. Springer Nature. 22