Archive for the 'Mathematics' Category

Das Dreikörperproblem

Wednesday, October 5th, 2016

… musste ich in meinem dritten Semester an der Uni für den Schein in theoretischer Physik Mechanik programmieren. Das sah natürlich längst nicht so schick aus wie diese Website, und davon abgesehen hatte ich einen Fehler im Programm, den ich erst nach mehreren Tagen gefunden habe – es war ein Vorzeichenfehler.

PhET Interactive Simulations, University of Colorado: My Solar System. (Flash)

You can simulate the orbits of two, three or four objects and change the mass, initial position and velocity for each one individually. Try to find stable or chaotic orbits!

Animated Math

Monday, September 12th, 2016

MetaFilter: Animated Math.

“Essence of linear algebra – “[Grant Sanderson of 3Blue1Brown (now at Khan Academy) animates] the geometric intuitions underlying linear algebra, making the many matrix and vector operations feel less arbitrary.””

I’m still working my way through these…

Brainteaser

Monday, August 8th, 2016

Physics Girl: Can you solve this pier puzzle? (YouTube)

“Can you figure it out? There are two towns near a shore. They want to build a pier on the shoreline with a path connecting the pier to each town. They want to use as little material as possible, so they need to put the pier in a location on the shoreline that minimizes the total length of both paths added together. Where should they put the pier?”

Mathematik im Abitur – oder doch nicht?

Tuesday, May 31st, 2016

Frankfurter Allgemeine Zeitung: Streit um Mathe-Abitur: Denken darf hier nur der Taschenrechner.

“Ein stumpfsinniger Stresstoleranztest: Niedersachsens Kultusministerium muss die Mathe-Klausuren der Abiturienten neu bewerten. Wie man es besser macht, zeigen die Finnen. Ein Gastbeitrag.” Von Hans-Jürgen Bandelt und Hans-Jürgen Matschull. “Hans-Jürgen Bandelt ist Professor für Mathematik an der Universität Hamburg, Hans-Jürgen Matschull lehrt Mathematik und Physik am Lichtenberg-Gymnasium in Cuxhaven.”

“Ich habe eine 113 gewürfelt…”

Saturday, April 30th, 2016

The New Yorker: The Dice You Never Knew You Needed.

“[T]wo scientists from the Dice Lab, Robert Fathauer and Henry Segerman, débuted their newest specimen, fresh from the petri dish. They had invented – or, rather, discovered; no, really they’d just inexplicably gone to the trouble of creating – a die with a hundred and twenty sides. “What do you use it for?” Fathauer asked the audience. “We have no idea,” he answered. Futility notwithstanding, the d120 is billed as the “ultimate fair die allowed by Mother Nature (i.e., mathematics!),” since a die couldn’t, practically speaking, possess more sides or more symmetry, and dice must be symmetrical to be fair.”

Watch the d120 in action on YouTube.

You can susbstitute the d120 for any dn in which n is a proper factor of 120; here’s a handy chart for this use.

Even though I don’t play any games that require more than a d6 or two and even though already own a d8, d12, d24, d30 (alphabet with 4 wildcards) and a d100 that I almost never use, I somehow feel like I need to also have a d120.

Links via MetaFilter: Or, disdyakis triacontahedron.