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Usual content below – Weblog weiter unten

Tomorrow the General Data Protection Regulation will be implemented. I had to make some changes to this weblog because of this. You should see a notification about cookies as well as information about data storage and handling when posting comments. The old theme I’ve been using for years and years didn’t seem to be able to cope with some of the updates, so I decided to go for a whole new look. I might still tinker with it during the next few days, but then again I might not.

Please let me know if you run into any problems or see something that doesn’t work, or if you have any general comments or tips for me. Thanks!

Morgen tritt die Datenschutz-Grundverordnung in Kraft. Deshalb musste ich einige Änderungen an diesem Weblog vornehmen. Leser sollten jetzt eine Benachrichtigung über das Speichern von Cookies bekommen und außerdem beim Kommentieren über Datenspeicherung und -verarbeitung in Kenntnis gesetzt werden. Das alte Layout, das ich seit Jahren verwendet habe, kam mit einigen dieser Aktualisierungen nicht zurecht, daher habe ich kurzerhand ein ganz neues gewählt, an dem ich vielleicht in den nächsten Tagen noch ein wenig herumbasteln werde.

Über Hinweise, falls etwas nicht funktioniert oder nicht so aussieht, wie es sollte, sowie für generelle Tipps und Vorschläge zum Design oder zum Datenschutz freue ich mich. Danke!

It’s a spherical video in a mathematically triplified space with symmetry in space-time

Vihart: Peace for Triple Piano. (YouTube 3D video, 4:15min)

This has got to be one of the most amazing things done with a 3D camera I’ve ever seen. Pro tip: Watch this in fullscreen mode on your phone so you can look around by moving the entire phone, and use headphones to get the full 3D sound effect as well.

Make sure to also watch

Henry Segerman: The Making of “Peace for Triple Piano”. (YouTube video, 13:52min including a “flat” version of the above 3D video).

In this video Vi Hart and Henry Sergerman explain how the video works: how they made one grand piano and one Vi look like three, but one Henry look like only two at the same time.

Vi writes a little more about this project on her weblog: Vihart.com: Peace for Triple Piano.

(This was published back in February, but I only now realized that the RSS feed of this YouTube channel stopped working.)

“Are you sure there isn’t something else we could calculate?”

XKCD What if: Earth-Moon Fire Pole. “My son (5y) asked me today: If there were a kind of a fireman’s pole from the Moon down to the Earth, how long would it take to slide all the way from the Moon to the Earth? – Ramon Schönborn, Germany”

I loved this and am tempted to use it in one of my next physics lessons…

Link via MetaFilter.

Researchers in U.S., U.K. measure volume of automated tweets, find that bots may have contributed to, even tipped, elections.

Bloomberg: Twitter Bots Helped Trump and Brexit Win, Economic Study Says.

“Twitter bots may have altered the outcome of two of the world’s most consequential elections in recent years, according to an economic study.

Automated tweeting played a small but potentially decisive role in the 2016 Brexit vote and Donald Trump’s presidential victory, the National Bureau of Economic Research working paper showed this month. Their rough calculations suggest bots added 1.76 percentage point to the pro-“leave” vote share as Britain weighed whether to remain in the European Union, and may explain 3.23 percentage points of the actual vote for Trump in the U.S. presidential race.

“Our results suggest that, given narrow margins of victories in each vote, bots’ effect was likely marginal but possibly large enough to affect the outcomes,””

Link via MetaFilter.

“When the actions of the parents, neighbors, and school fail, there remains one last backstop: The state.”

The Atlantic: The Futility of Trying to Prevent More School Shootings in America. “As long as there is easy access to guns, there’s no way parents, teachers, and other specialists can thwart every violent teenager.”

“Details are only beginning to emerge about the gunman, and now it seems he kept his plans to himself, described in his personal journal. This would be unusual. In many of the other 21 (by CNN’s count) school shootings this year, there were clues to what would come to pass, to varying degrees. Typically, someone—a parent, a classmate, a teacher, a neighbor—had a hunch as to what would happen. Sometimes it was clear the child was mentally ill. Sometimes he had overtly displayed psychopathic traits. Sometimes other students steered clear of that particular boy at lunch in the hallway, because he was just plain scary. As Mary Ellen O’Toole, a retired FBI agent who’s an expert on school shootings, notes: “They never come out of the blue.”

If the clues were there, couldn’t these teens have been stopped? Faced with a dangerous child, families, schools, and police can do their utmost, and their utmost frequently staves off tragedy. But events like this point to a discomforting reality: Even though many potentially violent children can be treated and do get better, it’s impossible to ensure that every dangerous child will be reached. And, in the end, there’s not much that anyone can do to stop a determined shooter, aside from preventing him from getting a gun in the first place.”