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Science and Technology links (January 16th 2021)

7 thoughts on “Science and Technology links (January 16th 2021)”

  1. Florian Habermacher says:

    Line 2. gave me the (admitedly vague) intuition there were various orders of magnitude fewer galaxies than originally thought. The article’s text then implies there may be something like, e.g., 4 or 5 times less than we had thought (original belief = 90% beyond detection, vs. now ca. half beyond detection). Given the somewhat difficult to grasp numbers of stars out there (and presumable uncertainties), one might even rather call this update a moderate change instead – and the universe thus being ‘relatively small’ thus also felt a bit like a stretch to me.

    1. If you were told that you hotel room was $500 a night and later learned that it was only $100 a night, would you agree that the cost is far cheaper than you thought and that the price is now relatively cheap?

      Being off by 4x or 5x is a large error in most things.

      1. Andrew Dalke says:

        The New Horizon press release has been corrected. “A prior version of this release indicated that the New Horizons observations were inconsistent with an earlier study that estimated there are 2 trillion galaxies in the universe. The New Horizons observations do not place a constraint on the total number of galaxies but rather do constrain the total amount of light all galaxies emit in the ultraviolet-optical bandpass”

        The new version says “Their result sets an upper limit to the starlight emitted by faint, unresolved galaxies, showing that there is about twice as much optical light permeating space as can be accounted for by all known galaxies.”

        1. Thank you. I have edited the blog post and effectively retired this point.

  2. A.M. says:

    The visible universe is less populated than previous estimates (10^11 rather than 10^12). The population of the entire universe, i.e. beyond the distance light has been able to travel since the Big Bang, remains unknown and cannot be measured by these methods.

  3. Pelle Bert says:

    While I’m definitely not an expert in the area, I just want to point out that some of the authors of the Cholesterol paper (the nordic ones) have previously also worked with known pseudo scientists and are also covid-19 skeptics. So it is probably best to read it with a skeptical eye.

    1. While I’m definitely not an expert in the area, I just want to point out that some of the authors of the Cholesterol paper (the nordic ones) have previously also worked with known pseudo scientists and are also covid-19 skeptics. So it is probably best to read it with a skeptical eye.

      Though you are welcome to make such comments, I would like to point out that it is an ad hominem attack. That is, you attack the authors and not the conclusion themselves (pseudo scientists, covid-19 skeptics). McCully in particular has been under a lifetime of personal attacks. See this 1997 article in the New York Times which concludes

      Worse, the political and economic forces that undid McCully back then may be more intense today. Last April, The New England Journal of Medicine published an article titled ”The Messenger Under Attack — Intimidation of Researchers by Special-Interest Groups,” which detailed three cases of harassment by advocacy groups, physicians’ associations or academic consultants who often failed to disclose their ties to drug companies. With more and more pressure groups weighing in on what research gets financed and promoted, the article said, ”such attacks may become more frequent and acrimonious.”

      I submit to you that it is a lot more interesting in science to focus on the scientific content rather than on the politics of the authors.