Category Archives: Mathematics

When adding a third filter lets through MORE light

3Blue1Brown with minutephysics: Some light quantum mechanics. “This is a simple primer for how the math of quantum mechanics, specifically in the context of polarized light, relates to the math of classical waves, specifically classical electromagnetic waves.”

minutephysics with 3Blue1Brown: Bell’s Theorem: The Quantum Venn Diagram Paradox. “This video is about Bell’s Theorem, one of the most fascinating results in 20th century physics. Even though Albert Einstein (together with collaborators in the EPR Paradox paper) wanted to show that quantum mechanics must be incomplete because it was nonlocal (he didn’t like “spooky action at a distance”), John Bell managed to prove that any local real hidden variable theory would have to satisfy certain simple statistical properties that quantum mechanical experiments (and the theory that describes them) violate. Since then, GHZ and others have managed to extend the theoretical work, and Alain Aspect performed the first Bell test experiment in the late 1980s.”

Rechenschwäche?

Süddeutsche Zeitung: Sind die Gene schuld – oder die Lehrer?

“Mathe ist doof. Das werden viele Kinder gedacht haben, als sie am Schuljahresende ihr Zeugnis gesehen haben. Manche von ihnen hätten für eine bessere Note vielleicht nur mehr üben müssen. Andere haben genau das getan – bis sogar Mama und Papa an 25 plus 17 verzweifelt sind.”

“Kinder mit Dyskalkulie werden behandelt, als sei ihnen nichts beizubringen”.

“Dabei sei es möglich, jedem Kind Grundlagen im Rechnen zu vermitteln, sagt [der Mathematikdidaktiker Wolfram Meyerhöfer]. Er hält die Rechenstörung für eine Ausrede der Schulen.”

Although the aircraft itself does not break the sound barrier, some of the air rushing around the curves of its wings goes supersonic.

The New York Times: Cathleen Morawetz, Mathematician With Real-World Impact, Dies at 94.

“Cathleen S. Morawetz, a mathematician whose theorems often found use in solving real-world engineering problems, died on Tuesday at her home in Manhattan. She was 94.

Her death was reported by New York University, where she had been a professor.

Much of Dr. Morawetz’s research centered on equations that describe the motion of fluids and waves — in water, sound, light and vibrating solids. One of her first notable papers helped explain the flow of air around airplanes flying close to the speed of sound.”

Aaron Numbers

“One reason why many mathematicians really like baseball: At the base of it, if you watch it on television, it’s a fairly boring game. It’s slow-moving, and it’s filled with numbers.”

Numberphile: Aaron Numbers. “A story of baseball, number theory, and serendipity. […] Featuring Carl Pomerance from the Department of Mathematics at Dartmouth College.”

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