Carlo? What was that?

This is quite upsetting. The question how Ivan Bogdanov managed to get into any football match is tied to the general security issues over the match in general. I’m blown away that UEFA has charged Albania with ‘refusing to play’. To be clear in not saying that I feel confident blaming anyone in particular (except those who ran on to attack others) but not wanting to play a game in that incredibly hostile atmosphere after a serious brawl and flares and fan invasions seems perfectly reasonable.

Reading of the Stela of Katumuwa. Aramaic. Zincircli, Turkey (ancient Sam’al), c. 735 BC.

An

Isochrone curveis the curve for which the time taken by an object sliding without friction in uniform gravity to its lowest point is independent of its starting point. The curve is a cycloid, and the time is equal to π times the square root of the radius over the acceleration of gravity.- A ball set on an Isocrone (or Tautochrone) curve will reach the bottom at the same length of time no matter where you place the ball, so long as there is no impeding friction.

[Gif] - Four balls slide down a cycloid curve from different positions, but they arrive at the bottom at the same time. The blue arrows show the points’ acceleration along the curve. On the top is the time-position diagram.

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