Links

2021 April 26

Music

Talos Principle OST - When in Rome

Philip Glass - Koyaanisqatsi

Moon OST - Welcome to Lunar Industries

Ayreon - Ride the comet

Scrope v Grosvenor was a 1389 dispute between two English families using the same coat of arms, azure, a bend or (a gold band across a blue background). The motifs and traditions developed over the previous century had only recently been solidified into heraldic law; both coats of arms had already been in use for some time. 700 years later a Grosvenor descendent named their son Bendor Grosvenor in recognition of the coat of arms they had lost the authority to use. Another member of the family owned the champion racehorse Bend Or.

Tennessee was the last state to ratify the 15th amendment, which protected the right to vote from denial “on account of race, color, or previous condition of servitude”… in 1997.

Stabbed while crocheting, “unspecified” spacecraft accident, and other bizarre causes of death recently given official codes in ICD-10. The stock photo of a shocked doctor is appropriate.

The plastic number

\rho = \sqrt[3]{\frac {9 + \sqrt{69}}{18}} + \sqrt[3]{\frac {9 - \sqrt{69}}{18}} = 1.3247\ldots

is the smallest number bigger than one whose exponents get closer to being integral (in the sense that the difference between \alpha^n and its nearest integer is \ell_2); such numbers are Pisot numbers. Specifically, \rho is a root of x^3 - x - 1, so if you construct the sequence r_0 = 1, r_1 = 1, r_2 = 2 with the “sub-Fibonacci” recurrence r_n = r_{n - 2} + r_{n - 3}, then \rho^n - r_n goes to zero as n becomes large. As \rho is quite close to 1, its conjugates are also close to 1, so the convergence \rho^n - r_n \to 0 is slow, but still exponential. Surprisingly \rho is not an accumulation point of the Pisot numbers: in fact, their smallest accumulation point is the golden ratio \phi = \frac {1 + \sqrt{5}}2 = 1.618\ldots, which is a root of x^2 - x - 1 and so whose powers approach the Fibonacci sequence. The fourth-smallest Pisot number is the “supergolden ratio” \psi, a root of x^3 - x^2 - 1, again with a corresponding recurrence. The term plastic number was coined by a Dutch architect who used it in designing the proportions of a church.

Covid articles: A fascinating, in-depth breakdown of the supply chains in the manufacture of the covid vaccines gives insight into the globalization of manufacturing. A summary of a study on evolution of spike proteins in a common cold coronavirus demonstrating a tendency towards immune escape on the time scale of decades. A primer on basic facts about covid vaccines written by a doctor. A potential adverse side effect of covid vaccines: one patient developed a heart arrhythmia after receiving a covid vaccine and being struck by lightning.

A Brief, Incomplete, and Mostly Wrong History of Programming Languages

Kasparov versus the World: current world chess champion Garry Kasparov played a game of chess in 1999 against the “World Team”, whose moves were decided by majority vote from all 50 000 people who chose to participate. Each ply took 24 hours. World Team was guided by four skilled chess players, and discussion was facilitated by an online forum, bringing with it every bit as much drama and controversy that one could expect. Kasparov called it the best and most-analyzed game of chess ever played.

Svg is far more featureful and complex than one might expect… remarkably, here is a website written entirely in svg. (There’s nothing particularly of note in the content in the website, and I never would have guessed that it is secretly just an svg file.) In fact, here is the full source code of the home page:

<!DOCTYPE html>
<html lang=en-US>
   <head>
      <link rel="icon" href="favicon.ico">
      <meta charset="UTF-8">
      <meta name = "description" content = "The latest news and blog posts from High Tower Games">
      <link rel="stylesheet" type="text/css" href="common/common.css">
      <title>High Tower Games ♜ News &amp; Blog ♜</title>
   </head>
   
   <body>
      <div class = "content">
         <div class = "svg_container">
            <object type="image/svg+xml" data="news.svg">
            </object>
         </div>
      </div>
   </body>
</html>

Videos

Violinist breaks a string during a concert performance, immediately switches to playing the same note on a different string and the violin gets passed down the violinist hierarchy to be restrung.

A heat pump is a device that spends energy to move heat from a cold side to a warm side: air conditioners, fridges, and freezers are all common examples of heat pumps. By simply turning an air conditioner around, one obtains a heat pump that heats a home instead of cooling it. Such consumer heat pumps tend to be use about one-fifth the energy of standard resistive heating (or natural gas heating), but are very rarely used for home heating in the US, whereas they are common in Europe and parts of Asia. Technology Connections has an introductory run down on heat pumps in a home setting, and their advantages and limitations. There is also a follow up discussing ground-sink heat pumps.

Oscillations in the frequency of the eastern US’s power grid caused by a blackout that took place in Florida.

Garson Hampfield, crossword inker.

Images

Near the southern-most point of Iceland.

The pompadour was named after Madame de Pompadour (above), who never wore one.

An adversarial attack on an image classifier.

A vantage point tree, from here.

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