Archive for the 'Mathematics' Category

Happy Thanksgiving!

Thursday, November 23rd, 2017

Here, have some mathed potatoes, green bean matherole with Borromean onion rings and, of course, a Thanksgiving Turduckenen-duckenen!

“Extremely likely” means a probability between 95 and 100%

Friday, November 3rd, 2017

If baffles me that there are still people denying the human influence on climate even though many studies show that it is extremely likely. I mean, if it is extremely likely that you will sustain serious injuries or die when jumping out of a third floor window, would you take the chances and jump?!

Part of the problem seems to be that many people don’t know enough about statistics, and that some politicians don’t trust the scientific method.

NPR The Two-Way: Massive Government Report Says Climate Is Warming And Humans Are The Cause.

“It is “extremely likely” that human activities are the “dominant cause” of global warming, according to the the most comprehensive study ever of climate science by U.S. government researchers.

The climate report, obtained by NPR, notes that the past 115 years are “the warmest in the history of modern civilization.” The global average temperature has increased by about 1.8 degree Fahrenheit over that period. Greenhouse gases from industry and agriculture are by far the biggest contributor to warming.

The findings contradict statements by President Trump and many of his Cabinet members, who have openly questioned the role humans play in changing the climate.

“I believe that measuring with precision human activity on the climate is something very challenging to do,” EPA Administrator Scott Pruitt said in an interview earlier this year. “There’s tremendous disagreement about the degree of impact.”

That is not consistent with the conclusions of the 600-plus page Climate Science Special Report, which is part of an even larger scientific review known as the fourth National Climate Assessment.
[…]
The report states that the global climate will continue to warm. How much, it says, “will depend primarily on the amount of greenhouse gases (especially carbon dioxide) emitted globally.” Without major reductions in emissions, it says, the increase in annual average global temperature could reach 9 degrees Fahrenheit relative to pre-industrial times. Efforts to reduce emissions, it says, would slow the rate of warming.
[…]
The report has been submitted to the Office of Science and Technology Policy at the White House. Trump has yet to choose anyone to run that office; it remains one of the last unfilled senior positions in the White House staff.”

When adding a third filter lets through MORE light

Monday, October 16th, 2017

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?

Tuesday, August 22nd, 2017

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.

Wednesday, August 16th, 2017

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.”