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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

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