Talk:Hubble’s law: Difference between revisions

	Hubble’s law was one of the Natural sciences good articles, but it has been removed from the list. There are suggestions below for improving the article to meet the good article criteria. Once these issues have been addressed, the article can be renominated. Editors may also seek a reassessment of the decision if they believe there was a mistake.
Current status: Delisted good article

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This article has previously been nominated to be moved. Please review the prior discussions if you are considering re-nomination. Discussions: RM, Hubble’s law → Hubble–Lemaître law, Not moved, 1 November 2018, discussion RM, Hubble’s law → Hubble–Lemaître law, Not moved, 1 January 2023, discussion

The article states: “after Hubble confirmed cosmic expansion and determined a more precise value for it two years later”. It may have been more precise, but Hubble’s estimate was wildly inaccurate (classic example of confusing precision and accuracy!). His published estimate was 500 km/s/Mpc, giving an age for the universe of 2 billion years – very problematic as the Earth was known to be older than that! Astronomers weren’t bothered by the discrepancy, as they could see the idea of the law was correct even if the value was wrong, they just had to wait for better data. Hubble had more data points than Lemaitre, as he was extending the data Lemaitre had used (Strömberg’s list, which included some measurements by Hubble). Aarghdvaark (talk) 09:43, 12 August 2025 (UTC)[reply]

Do you have a suggested change to the article with a source for it? Johnjbarton (talk) 13:53, 12 August 2025 (UTC)[reply]

Talk:Hubble’s law/Archive 4 – Wikipedia See previous discussion on this. Banedon (talk) 04:41, 13 August 2025 (UTC)[reply]

Thanks, that clears that up in that we’re reflecting the IAU. Aarghdvaark (talk) Aarghdvaark (talk) 05:36, 17 August 2025 (UTC)[reply]

https://www.google.com/search?q=1%252F((67.8+km%252Fs)%252FMpc)
returns 251,711,776 years. 73.147.27.140 (talk) 16:04, 14 August 2025 (UTC)[reply]

Since around the beginning of this year, Google calculator now gives blatantly wrong answers for calculations involving parsecs. Here’s the same expression using a calculator that works: https://gutcalc.com/?q=MS8oNjcuOCBrbS9zL01wYykgaW4geXI= Aseyhe (talk) 08:38, 15 August 2025 (UTC)[reply]

As best I can tell, you are pointing to the output of an LLM. Don’t do that, see WP:LLM, LLMs are not authoritative and have no place on Wikipedia. And even at that, you seem to have misinterpreted the summary paragraph, 1/67.8 km/s/Mpc. If you click “show more” on that LLM’s output, you see that it actually does the arithmetic (or quotes someone who does) to come up with 14.4 billion years. — Preceding unsigned comment added by Tarl N. (talk • contribs)

Could someone please kindly add the following improvements to the excellent big picture ‘Landscape of H0’ table located opposite the paragraph titled ‘Reducing systematic errors’:

1. Give the table a title name e.g. ‘The Landscape of the Hubble Tension’;
2. Show with sub-headings that CMB measurements are ΛCDM model dependent, and the remainder like all the SNe and galaxy cluster types are Independent of the ΛCDM model;
3. Clarify under the sub-heading ‘Optimistic Average’ whether the di Valentino Average (Mean) includes CMB or not? Because it looks like it does not;
4. Show under the sub-heading’Optimistic Average’ the Chen & Ratra older mean result of H0=68 ^[1] And add the above citations to the references;
5. Update table by adding new post-2021 published results, including references; and
6. At the bottom of the table add the new sub-heading ‘Means of All Tabled Measurements’, and calculate and provide the mean values with respective sub-heading for:
   1. All CMB Tabled Measurements;
   2. All TRGB-SNeIa Tabled Measurements;
   3. All Non CBM & TRGB-SNeIa Tabled Measurements; and
   4. Mean of All Tabled Measurements

Include the mean error bars if possible.
Thanks 49.186.235.55 (talk) 01:06, 1 September 2025 (UTC)[reply]

As suggested by @Spartan S58, once this paper has appeared in a reviewed journal we can add

• In 2025 the TDCOSMO collaboration, using a dataset of mostly quasars, published a result of 71.6+3.9
  −3.3 (km/s)/Mpc (superseding 2020 results whose assumptions were found to be overly strong).
• Collaboration, TDCOSMO; et al. (2025). “TDCOSMO 2025: Cosmological constraints from strong lensing time delays”. arXiv:2506.03023 [astro-ph.CO].

Johnjbarton (talk) 16:23, 24 October 2025 (UTC)[reply]

While frequency does have 1/s units, not everything with 1/s units is a frequency. Only periodic, or at least close to periodic, things have frequencies. Gah4 (talk) 11:26, 20 November 2025 (UTC)[reply]

What is this comment in reference to? Johnjbarton (talk) 17:27, 20 November 2025 (UTC)[reply]

@Johnjbarton: My guess: The fact that the article refers to ${\displaystyle H_{0}}$ as a “frequency”, without making it clear why that’s a sensible thing to do. The only place in the article that mentions this is the last paragraph of the lede; it is not referred to again in the article body and that part doesn’t have a citation. Our article frequency would indeed imply that it refers to a repeating event, and it is not self-evident what is repeating at a frequency of ${\displaystyle H_{0}}$. Since it’s not self evident, we need a reference (and I am tagging it as such). Renerpho (talk) 02:21, 21 November 2025 (UTC)[reply]