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arxiv: astro-ph/9812133 · v1 · submitted 1998-12-08 · 🌌 astro-ph · hep-ex· hep-ph

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Measurements of Omega and Lambda from 42 High-Redshift Supernovae

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Pith reviewed 2026-05-10 19:59 UTC · model grok-4.3

classification 🌌 astro-ph hep-exhep-ph
keywords Type Ia supernovaecosmological constantOmega_MOmega_Lambdamagnitude-redshift relationaccelerating expansionflat cosmologysupernova survey
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The pith

The analysis of 42 high-redshift Type Ia supernovae indicates that the cosmological constant is non-zero and positive.

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

This paper reports measurements of the universe's mass density Omega_M and cosmological constant density Omega_Lambda based on 42 Type Ia supernovae discovered at redshifts from 0.18 to 0.83. These are standardized using the lightcurve width-luminosity relation and compared to nearby supernovae to fit the magnitude-redshift relation. The fit gives a relation between the densities and shows strong inconsistency with models having zero cosmological constant. If correct, this means the expansion of the universe is accelerating due to a positive Lambda term.

Core claim

The magnitude-redshift data for these SNe are fit jointly with a set of SNe from the Calan/Tololo Supernova Survey to yield values for the cosmological parameters. The measurement yields a joint probability distribution approximated by 0.8 Omega_M - 0.6 Omega_Lambda ~= -0.2 +/- 0.1. For a flat cosmology the data give Omega_M = 0.28 with statistical and systematic errors. The data are strongly inconsistent with a Lambda = 0 flat cosmology and indicate the cosmological constant is non-zero and positive with 99% confidence.

What carries the argument

Type Ia supernovae standardized by the lightcurve width-luminosity relation serving as standard candles for the magnitude-redshift relation.

If this is right

  • In a flat universe, Omega_M is about 0.28 and Omega_Lambda about 0.72.
  • The age of the universe is 14.9 Gyr scaled by 0.63/h.
  • Open Lambda=0 cosmologies do not fit the data well.
  • Statistical tests show no significant differences in host reddening or Malmquist bias between samples.

Where Pith is reading between the lines

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

  • The result supports the idea of a dominant energy component causing acceleration at the present epoch.
  • It suggests that combining supernova data with other observations like galaxy clustering could further constrain the parameters.
  • Higher redshift supernovae could probe whether the acceleration has been constant or varied over time.

Load-bearing premise

That Type Ia supernovae at high redshift can be standardized to the same intrinsic luminosity as local ones using the lightcurve width-luminosity relation, with no significant evolutionary changes or unrecognized systematics between the samples.

What would settle it

An observation that the lightcurve width-luminosity relation fails to standardize high-redshift supernovae in the same way as local ones, or that there are unrecognized differences in their host environments affecting the magnitudes.

read the original abstract

We report measurements of the mass density, Omega_M, and cosmological-constant energy density, Omega_Lambda, of the universe based on the analysis of 42 Type Ia supernovae discovered by the Supernova Cosmology Project. The magnitude-redshift data for these SNe, at redshifts between 0.18 and 0.83, are fit jointly with a set of SNe from the Calan/Tololo Supernova Survey, at redshifts below 0.1, to yield values for the cosmological parameters. All SN peak magnitudes are standardized using a SN Ia lightcurve width-luminosity relation. The measurement yields a joint probability distribution of the cosmological parameters that is approximated by the relation 0.8 Omega_M - 0.6 Omega_Lambda ~= -0.2 +/- 0.1 in the region of interest (Omega_M <~ 1.5). For a flat (Omega_M + Omega_Lambda = 1) cosmology we find Omega_M = 0.28{+0.09,-0.08} (1 sigma statistical) {+0.05,-0.04} (identified systematics). The data are strongly inconsistent with a Lambda = 0 flat cosmology, the simplest inflationary universe model. An open, Lambda = 0 cosmology also does not fit the data well: the data indicate that the cosmological constant is non-zero and positive, with a confidence of P(Lambda > 0) = 99%, including the identified systematic uncertainties. The best-fit age of the universe relative to the Hubble time is t_0 = 14.9{+1.4,-1.1} (0.63/h) Gyr for a flat cosmology. The size of our sample allows us to perform a variety of statistical tests to check for possible systematic errors and biases. We find no significant differences in either the host reddening distribution or Malmquist bias between the low-redshift Calan/Tololo sample and our high-redshift sample. The conclusions are robust whether or not a width-luminosity relation is used to standardize the SN peak magnitudes.

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

1 major / 0 minor

Summary. The paper reports measurements of Omega_M and Omega_Lambda from magnitude-redshift data of 42 high-redshift Type Ia supernovae (0.18 < z < 0.83) discovered by the Supernova Cosmology Project, jointly fit with low-redshift SNe from the Calan/Tololo survey. All peak magnitudes are standardized via a lightcurve width-luminosity relation. For a flat universe the fit yields Omega_M = 0.28^{+0.09}_{-0.08} (1 sigma statistical) ^{+0.05}_{-0.04} (identified systematics). The data are stated to be strongly inconsistent with a flat Lambda=0 cosmology and to indicate P(Lambda > 0) = 99% including systematics; the constraints are summarized by the approximate relation 0.8 Omega_M - 0.6 Omega_Lambda ~ -0.2 +/- 0.1. Multiple statistical tests for biases are reported, with no significant differences found in host reddening or Malmquist bias distributions, and results claimed to be robust with or without the width-luminosity correction.

Significance. If the standardization assumption holds without significant redshift-dependent evolution, the result provides the first direct supernova evidence for a positive cosmological constant, ruling out the simplest flat Lambda=0 inflationary model at high confidence and implying an accelerating universe. The large sample size enabling explicit bias checks and the presentation of the joint probability distribution via the linear degeneracy relation are strengths that make the constraints more transparent and testable.

major comments (1)
  1. [Abstract and analysis of standardization robustness] The central claim that the data indicate P(Lambda > 0) = 99% rests on the standardization of all SNe via the width-luminosity relation and the assertion that conclusions remain robust without it. However, the reported checks (no significant differences in host reddening or Malmquist bias distributions between the Calan/Tololo and high-z samples) do not directly constrain possible redshift evolution in the slope or zero-point of the width-luminosity relation itself. Such evolution would shift the entire magnitude-redshift locus and could move the best-fit point along the reported degeneracy direction (0.8 Omega_M - 0.6 Omega_Lambda ~ -0.2) enough to weaken the Lambda > 0 preference.

Simulated Author's Rebuttal

1 responses · 0 unresolved

We thank the referee for their careful and constructive review of our manuscript. We address the major comment below and indicate the revisions we will make to strengthen the presentation of our robustness tests.

read point-by-point responses
  1. Referee: The central claim that the data indicate P(Lambda > 0) = 99% rests on the standardization of all SNe via the width-luminosity relation and the assertion that conclusions remain robust without it. However, the reported checks (no significant differences in host reddening or Malmquist bias distributions between the Calan/Tololo and high-z samples) do not directly constrain possible redshift evolution in the slope or zero-point of the width-luminosity relation itself. Such evolution would shift the entire magnitude-redshift locus and could move the best-fit point along the reported degeneracy direction (0.8 Omega_M - 0.6 Omega_Lambda ~ -0.2) enough to weaken the Lambda > 0 preference.

    Authors: We agree that the checks on host reddening and Malmquist bias distributions do not directly constrain possible redshift evolution in the parameters of the width-luminosity relation. However, the manuscript already reports that the cosmological conclusions are robust when the width-luminosity relation is not applied at all. In this uncorrected analysis, no standardization is performed and therefore no assumption is made about the slope or zero-point of the relation or any possible redshift dependence. Even without the correction, the high-redshift supernovae lie systematically below the magnitude-redshift relation expected for a flat Lambda=0 cosmology, yielding a comparable preference for positive Omega_Lambda. We will revise the manuscript to explicitly highlight this distinction and to note that the no-correction results are independent of uncertainties in the width-luminosity relation, thereby addressing the referee's concern about potential evolution. revision: yes

Circularity Check

0 steps flagged

No significant circularity: cosmological parameters obtained via direct data fit

full rationale

The paper derives Omega_M and Omega_Lambda by jointly fitting the magnitude-redshift relation of 42 high-z SNe Ia (standardized with the lightcurve width-luminosity relation) and the Calan/Tololo low-z sample to the standard FLRW luminosity-distance formula. The resulting degeneracy relation 0.8 Omega_M - 0.6 Omega_Lambda ~ -0.2 is the direct output of this chi-squared minimization on the observed data points; the 99% confidence for Lambda > 0 is the integral over the likelihood surface. The paper states that results are robust without the width-luminosity correction and reports no significant differences in host reddening or Malmquist bias distributions between samples. No step reduces the claimed result to its inputs by definition, by renaming a fitted parameter as a prediction, or by load-bearing self-citation of an unverified uniqueness theorem. The derivation is therefore self-contained against the supernova observations within the assumed cosmological model.

Axiom & Free-Parameter Ledger

2 free parameters · 2 axioms · 0 invented entities

The central claim rests on the standardization of supernovae magnitudes and the standard FLRW cosmological model; the fitted parameters are the direct output of the data analysis.

free parameters (2)
  • Omega_M = 0.28 +0.09 -0.08
    Fitted directly from the joint magnitude-redshift data for the flat cosmology case.
  • Omega_Lambda = 0.72
    Inferred from the flatness constraint and the data fit.
axioms (2)
  • domain assumption Type Ia supernovae peak magnitudes can be standardized using a lightcurve width-luminosity relation that holds across the observed redshift range
    Invoked to correct all peak magnitudes before fitting the cosmological model.
  • standard math The magnitude-redshift relation is described by the Friedmann equation in a homogeneous isotropic universe containing matter and a cosmological constant
    Used as the model to which the standardized supernova data are fit.

pith-pipeline@v0.9.0 · 5871 in / 1510 out tokens · 66985 ms · 2026-05-10T19:59:03.841360+00:00 · methodology

discussion (0)

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Reference graph

Works this paper leans on

13 extracted references · 13 canonical work pages · cited by 46 Pith papers · 2 internal anchors

  1. [1]

    A., & Fan, X

    Baade 1938, ApJ, 88, 285 Bahcall, N. A., & Fan, X. 1998, Ap.J. (also available at astro-ph/9803277), in press Bernstein, G., & Tyson, J. A. 1998, http://www.astro.lsa.umich.edu/btc/user.html Branch, D. 1998, Ann. Rev. Astro. Astrophys., 36, 17 Branch, D., Lacy, C. H., McCall, M. L., Sutherland, P. G., Uomoto, A., Wheeler, J. C., & Wills, B. J. 1983, ApJ, ...

  2. [2]

    6: Supernovae, The Netherlands: ESA Cardelli, J

    IUE - ULDA Access Guide No. 6: Supernovae, The Netherlands: ESA Cardelli, J. A., Clayton, G. C., & Mathis, J. S. 1989, ApJ, 345, 245 Carlberg, R. G. 1997, astro-ph/9708054 Carlberg, R. G., et al. 1998, astro-ph/9804312 Carlberg, R. G., Yee, H. K. C., Ellingson, E., Abraham, R., Gravel, P., Morris, S., & Pritchet, C. J. 1996, ApJ, 462, 32 Carroll, S. M., P...

  3. [3]

    Ruiz-Lapuente, R

    In Presentations at the NATO ASI i n Aiguablava, Spain, LBL-38400, page III.1; also published in Thermonuclear Supernova, P. Ruiz-Lapuente, R. Canal, and J.Isern, editors, Dordrecht: Kluwer, page 777 (1997) Goldhaber, G., et al. 1998, Ap.J., in preparation Goobar, A., & Perlmutter, S. 1995, ApJ, 450, 14 Gordon, K. D., & Clayton, G. C. 1998, ApJ, 500, 816 ...

  4. [4]

    1996, A&A, 318,

    Kayser, R., Helbig, P., & Schramm T. 1996, A&A, 318,

  5. [5]

    1998, ApJ, in preparation Kim, A., Goobar, A., & Perlmutter, S

    Kim, A., et al. 1998, ApJ, in preparation Kim, A., Goobar, A., & Perlmutter, S. 1996, PASP, 108, 190 Kirshner, R., et al. 1993, ApJ, 415, 589 Kirshner, R., & Oke, J. 1975, ApJ, 200, 574 Kochanek, C. S. 1996, ApJ, 466, 638 Leibundgut, B., et al. 1996a, Ap.J.Lett., 466, L21 Leibundgut B. et al. 1996b, Ap.J.Lett., 371, L23 Lineweaver, C. H. 1998, ApJ, Lett.,...

  6. [6]

    Freeman Nørgaard-Nielsen, et al

    Galactic Astronomy: Structure and Kinematics, 2nd ed., San Francisco: W.H. Freeman Nørgaard-Nielsen, et al. 1989, Nature, 339, 523 Nugent, P., Branch, D., Baron, E., Fisher, A., Vaughan, T., &Hauschildt, P. 1995, Phys.Rev.Lett., 75, 394, and erratum,75, 1874 Nugent, P., et al. 1998, PASP, in preparation Oke, J., et al. 1995, PASP, 107, 375 Oliver, S. J., ...

  7. [7]

    Ruiz-Lapuente, R

    In Thermon uclear Supernova, P. Ruiz-Lapuente, R. Canal, and J.Isern, editors, Dordrecht: Kluwer, page 205 Saha, A., et al. 1997, ApJ, 486, 1 Schlegel, D., Finkbeiner, D., & Davis, M. 1998, ApJ, in press Schmidt, B. P., et al. 1998, ApJ, in press Schramm, D. N

  8. [8]

    Vangioni-Flamet al., editors, Gif sur Yvette: Edition Frontiers, page 365 Sigad, Y ., Eldar, A., Dekel, A., Strauss, M

    In Astrophysical Ages and Dating Methods, E. Vangioni-Flamet al., editors, Gif sur Yvette: Edition Frontiers, page 365 Sigad, Y ., Eldar, A., Dekel, A., Strauss, M. A., & Yahil, A. 1998, ApJ, 495, 516 Smail, I., Hogg, D. W., Yan, L., & Cohen, J. G. 1995, ApJ, 449, L106 Steinhardt, P. J. 1996, Nature, 382, 768 Tammann, G. A

  9. [9]

    Macchetto, F

    In ESA/ESO Workshop on Astronomical Use s of the Space Telescope, F. Macchetto, F. Pacini, and M. Tarenghi, editors, Geneva: ESO, page 329 Tegmark, et al. 1998, astro-ph/9805117 Tripp, R. 1998, A&A, 331, 815 Turner, M. S., & White, M. 1997, Phys. Rev. D, 56, R4439 Vacca, W. D., & Leibundgut, B. 1996, ApJ, 471, L37 Wambsganss, J., Cen, R., & Ostriker, J. P...

  10. [10]

    bBayesian method of Riess et al

    Best Fit Fit Description ΩM, ΩΛ Inclusive Fits A 60 98 56 0.29 +0.09 −0.08 0.9984 0.83,1.42 All SNe B 56 60 52 0.26 +0.09 −0.08 0.9992 0.85,1.54 Fit A, but excluding 2 residual outliers and 2 stretch outliers Primary Fit C 54 56 50 0 .28+0.09 −0.08 0.9979 0.73,1.32 Fit B, but also excluding 2 likely reddened Comparison Analysis Techniques D 54 53 51 0.25 ...

  11. [11]

    stretch factor,

    (b) The magnitude resid uals from the best-fit flat cosmology for the Fit C supernova su bset, (ΩM, ΩΛ) = (0.28,0.72). The dashed curves are for a range of flat cosmological mod els: ( ΩM, ΩΛ) = (0,1) on top, (0 .5,0.5) third from bottom, (0.75,0.25) second from bottom, and (1,0) is the solid curve on bottom. The middle solid curve is for (ΩM, ΩΛ) = (0,0). N...

  12. [12]

    no big bang,

    (b) The restframe B−V color excess for the 36 high-redshift supernovae for which r estframe B−V colors were measured, also corrected for Galactic extinction. The darker shading indicates those E(B−V) measurements with uncertainties less than 0.3 mag, unshad ed boxes indicate uncertainties greater than 0.3 mag, and the light shading indicates the two super...

  13. [13]

    32 Ω Μ 1 2 0 1 2 3 Ω Λ -1 0 1 2 3 2 3 19 Gyr 14.3 Gyr accelerating decelerating 11.9 Gyr 9.5 Gyr 7.6 Gyr H0t0 63 km s-1 Mpc-1 = FIG

    only accounting for up to ΩM = 0.25 of the critical mass density, and any matter beyond that amount smoothly distributed (i.e., η rising to 0.75 at ΩM = 1). 32 Ω Μ 1 2 0 1 2 3 Ω Λ -1 0 1 2 3 2 3 19 Gyr 14.3 Gyr accelerating decelerating 11.9 Gyr 9.5 Gyr 7.6 Gyr H0t0 63 km s-1 Mpc-1 = FIG. 9.— Isochrones of constant H0t0, the age of the universe relative t...