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    • CommentRowNumber1.
    • CommentAuthorUrs
    • CommentTimeMar 23rd 2019

    added this, under References – Review:


    In March 2013, following an accurate processing of available measurement data, the Planck Scientific Collaboration published the highest-resolution photograph ever of the early Universe when it was only a few hundred thousand years old. The photograph showed galactic seeds in sufficient detail to test some nontrivial theoretical predictions made more than thirty years ago. Most amazing was that all predictions were confirmed to be remarkably accurate. With no exaggeration, we may consider it established experimentally that quantum physics, which is normally assumed to be relevant on the atomic and subatomic scale, also works on the scale of the entire Universe, determining its structure with all its galaxies, stars, and planets.

    diff, v22, current

    • CommentRowNumber2.
    • CommentAuthorUrs
    • CommentTimeMar 23rd 2019

    added also pointer to video recording of the talk: video recording

    diff, v22, current

    • CommentRowNumber3.
    • CommentAuthorUrs
    • CommentTimeJul 26th 2019

    added pointer to today’s

    • L. Verde T. Treu, A.G. Riess, Tensions between the Early and the Late Universe (arXiv:1907.10625)

    something is going on.

    diff, v23, current

    • CommentRowNumber4.
    • CommentAuthorUrs
    • CommentTimeJul 26th 2019

    Or maybe not:

    arxiv.org/abs/1907.05922

    • CommentRowNumber5.
    • CommentAuthorUrs
    • CommentTimeJul 27th 2019
    • (edited Jul 27th 2019)

    gave the articles on Hubble-tension (or not) their own subsection.

    diff, v24, current

    • CommentRowNumber6.
    • CommentAuthorDavid_Corfield
    • CommentTimeJul 27th 2019

    Don’t you just love the precision of astrophysics. One knows that this “tension” will be resolved at some point, but that it’s even possible to generate such levels is a testament to the power and variety of observation techniques.

    The gulf between this and particle physics, on one side, and the likes of psychology and pharmacology, on the other, is vast.

    • CommentRowNumber7.
    • CommentAuthorUrs
    • CommentTimeJul 27th 2019
    • (edited Jul 27th 2019)

    Welcome to the exact sciences. Proudly serving precision since 1687.

    • CommentRowNumber8.
    • CommentAuthorDavid_Corfield
    • CommentTimeJul 27th 2019

    Yes, but the speed in the drop-off of exactness as we leave physics behind isn’t always recognised.

    • CommentRowNumber9.
    • CommentAuthorUrs
    • CommentTimeJul 27th 2019

    Sorry for the joking comment, that was on a whim.

    From previous discussion that we had, I can gather that what is going on with comments as in your #6 – which look a tad odd when seen without background knowledge of where you are coming from: My understanding is that you had in the past been involved in lively discussion of improper usage of statistical methods in the non-exact sciences, as practiced by non-mathematically educated “soft” scientists, and you had not before seen, or at least not got involved in to similar degree, the use of the same kind of methods in the exact sciences by practitioners who, while not pure mathematicians, are skilled in applying mathematics properly. It is the usage of the concept of statistical significances by astrophysiocist that catches your eye here as an ingredient mentioned in passing in discussion of the big “Hubble tension” issue of these days, reminding you of the occurrence of the concept that you had seen used in psychology and pharmacology.

    Taken out of this implicit personal context of yours, it may seem odd to bystanders to comment on standard astrophysics research by comparing it to, of all fields, psychology or pharmocology. We don’t usually compare any topics here to psychology or pharmacology, for their far remoteness from the main subject matter of the nLab. That stark dichotomy inspired my little joking comment above, sorry for that. But I suggest that if there is further discussion about the use and misuse of the concept of statistical significance in the excact and, if needed, also in the soft sciences, we have that in a dedicated entry.

    There is something fascinating going on here with the “Hubble tension”-issue, be it either a real effect or a systematics error, and with some luck we might get some experts maybe to join in here and share some thoughts or input.

    • CommentRowNumber10.
    • CommentAuthorUrs
    • CommentTimeFeb 18th 2020

    added pointer to today’s

    • George Efstathiou, Steven Gratton, The evidence for a spatially flat Universe (arXiv:2002.06892)

    diff, v25, current

    • CommentRowNumber11.
    • CommentAuthorGuest
    • CommentTimeAug 16th 2022

    I don’t have editing permissions on the nLab but there is this article from a few months ago:

    • Elcio Abdalla, Guillermo Franco Abellán, et al., Cosmology Intertwined: A Review of the Particle Physics, Astrophysics, and Cosmology Associated with the Cosmological Tensions and Anomalies (arXiv:2203.06142v3)
    • CommentRowNumber12.
    • CommentAuthorUrs
    • CommentTimeAug 16th 2022
    • (edited Aug 16th 2022)

    Thanks for the suggestion! I have now added the pointer here.

    By the way, where you write

    I don’t have editing permissions on the nLab

    it sounds a little mysterious: For better or worse, hitting “edit” at the bottom of any nLab page does not require any kind of sign-in.

    diff, v28, current

    • CommentRowNumber13.
    • CommentAuthorGuest
    • CommentTimeAug 16th 2022

    I get this message whenever I try to edit the page and submit to the edits

    Hello anonymous editor. Please respond to https://nforum.ncatlab.org/discussion/14612/flood-of-unresponsive-anonymous-edits/?Focus=99880#Comment_99880 before making any further edits!

    I have no idea what is going on there, because I certainly didn’t make any of the edits mentioned there. I don’t even know what any of those topics are. I’m mostly just interested in cosmology and astrophysics and related topics.

    Might be directed towards the previous tenant who was living in this apartment, because I just moved in a few days ago.

    • CommentRowNumber14.
    • CommentAuthorUrs
    • CommentTimeAug 16th 2022

    Interesting story.

    We could look into doing something about this. If so, do you feel it is important that you remain anonymous here?

    • CommentRowNumber15.
    • CommentAuthorGuest
    • CommentTimeAug 16th 2022

    I personally don’t care about whether I remain anonymous here or not.

    But one thing I find odd about this wiki is that there is no way to distinguish between different people’s edits on the nlab. Especially with anonymous users. There is no account system like many other wikis do, such as Wikipedia, so there is no way to link up edits to some user. Relying on IP address only doesn’t really work as people move all the time, public IP addresses exist (such as at libraries, restaurants, universities et cetera), apartments constantly rotate around which tenant gets which IP address, et cetera.

    I would rather have an account system so my edits could be distinguished from others who lived at my apartment in the past.

    • CommentRowNumber16.
    • CommentAuthorGuest
    • CommentTimeAug 16th 2022
    *so I could create an account and have my edits be distinguished by the anonymous editor who seemed to be active before me.
    • CommentRowNumber17.
    • CommentAuthorUrs
    • CommentTimeAug 16th 2022

    Exactly, that’s why I am wondering if you have a name and preferably a webpage that you could sign with.

    • CommentRowNumber18.
    • CommentAuthorJ-B Vienney
    • CommentTimeAug 16th 2022
    • (edited Aug 16th 2022)

    When you make an edit, write your pseudo like this:

    ” Submit as #pseudo

    Then, all your edits will be linked to this pseudo. You can even describe yourself on the page related to this pseudo. There is no formal system of accounts but everything is like if it was the case if you always use the same pseudo. You can chose an uninformative word for your pseudo or better your real name if you accept.

    • CommentRowNumber19.
    • CommentAuthorUrs
    • CommentTimeAug 16th 2022

    That’s the default. But the user IP in question has been banned before for abusing this system (this for the first time in the history of the nLab). To lift that ban it would help to see more than a story about further anonymous tenants of unspecified apartments.

  1. adding reference

    • Michael Boylan-Kolchin, Stress Testing ΛCDM with High-redshift Galaxy Candidates, (arXiv:2208.01611)

    Anonymous

    diff, v30, current

  2. Adding reference about the Hubble tension

    Anonymous

    diff, v30, current

  3. adding reference

    • Nikita Lovyagin, Alexander Raikov, Vladimir Yershov, Yuri Lovyagin, Cosmological Model Tests with JWST. (arXiv:2212.06575)

    Anonymous

    diff, v31, current

  4. Adding reference

    Pavan Kumar Aluri, Paolo Cea, Pravabati Chingangbam, Ming-Chung Chu, Roger G. Clowes, Damien Hutsemékers, Joby P. Kochappan, Alexia M. Lopez, Lang Liu, Niels C. M. Martens, C. J. A. P. Martins, Konstantinos Migkas, Eoin Ó Colgáin, Pratyush Pranav, Lior Shamir, Ashok K. Singal, M. M. Sheikh-Jabbari, Jenny Wagner, Shao-Jiang Wang, David L. Wiltshire, Shek Yeung, Lu Yin, Wen Zhao, Is the Observable Universe Consistent with the Cosmological Principle?, Classical and Quantum Gravity, Volume 40, Number 9, 4 April 2023. (doi:10.1088/1361-6382/acbefc, arXiv:2207.05765)

    Abram

    diff, v32, current

    • CommentRowNumber24.
    • CommentAuthorUrs
    • CommentTimeJun 27th 2023

    I have cross-linked that reference to inhomogeneous cosmology (where the preprint version had been referenced earlier, but I have updated there now with the publication data)

    diff, v33, current