## Thursday, April 26, 2018 ... /////

### Volumes of higher-dimensional balls from Gaussians: the coolness and conceptual implications

Bill Zajc has agreed with me that the derivation of the volume of an $N$-dimensional ball$V_N (R) = \frac{\pi^{N/2} } { \zav{\frac N2}! } R^N$ where $X!$ is the generalized factorial i.e. $X! = X\cdot (X-1)!$, $0!=1$, $(-1/2)!=\sqrt{\pi}$, is something that simply has to impress a kid who has a mathematical heart, especially the kind of a mathematical heart that is relevant for theoretical physics.

I will try to discuss the derivation including some comments why it's so cool and what one learns.

First, at some moment, the kid learns that the exponential with the base $e\approx 2.718$ is the most natural function needed to write powers. Along with its inverse, the natural logarithm, it may be used to write down a general power:$x^y = \exp(y \log x).$ That's cool. On top of that, $\exp(x)$ has itself as the derivative. We may differentiate and integrate $\exp(x)$ easily as in the joke about the functions that walk on the street and they're terrified to death when the derivative emerges in front of them. Only one function seems courageous. "Aren't you terrified of me?" the derivative asks. "No, I am the exponential."

### Why 1 isn't prime

Natalie Wolchover is among those who believe that one should be considered a prime integer:

Well, she's wrong. One isn't prime exactly because it's not a building block of natural numbers. More precisely, it's totally useless as a building block.

Or as a follower of hers wrote:

The point is that the factor "one" isn't needed to write the prime integer decomposition of an integer. You may always add "times one" whereover you want but it changes nothing.

## Wednesday, April 25, 2018 ... /////

### Germany bans Jews in the streets, demands worshiping of electric cars

The ongoing cultural transformation of Germany is rather amazing. Bavaria, self-confident Germany's Texas, seems to be the only adult Bundesland in the room. For example, to fight against de-Christianization, the heavily Catholic state's government has ordered crosses onto walls of all government buildings. It's legal because the cross isn't installed to show the power of any church; it is not a symbol of any particular church, it is the symbol for Hermitian conjugation.

The rest of Germany follows very different trends, however.

Last week, Arab Israeli Adam Armoush didn't want to believe claims that it was dangerous to walk in the streets of Berlin with a yarmulka (that's our Slavic name for the skullcap, originally used in Polish and Ukrainian and then Yiddish; it's also called kippah which means a dome), a brimless traditional cap that believing male Jews have to wear in order not to insult a deity (well, HaShem) that watches them from above at all times. The orthodox rules are tough – you can't walk for more than 4 units of distance without the yarmulka, you can only remove it for "Amen" during your wedding etc.

So Adam took a yarmulka, gave another one to his pal, and they went. They were quickly attacked by a similarly looking Syrian "refugee" with a belt (who screamed "Yahudi" i.e. "Jude" etc.) and the incident was filmed by the victim. All men are around 20 years old.

## Tuesday, April 24, 2018 ... /////

### It's wrong to summarize the multiverse as "left-wing"

And Keating's proposed Nobel prize reforms are left-wing lunacy

Nick has asked whether Brian Keating, the designer of BICEP1 and the author of "Losing the Nobel Prize" (which will be released today), was conservative. At least according to some methodologies, the answer is Yes.

His 50-minute interview in Whiskey Politics, a right-wing podcast, has shown that he had the courage to hang the picture of George W. Bush in his University of California office – where most of his colleagues would prefer to hang Bush himself. Well, he didn't support Trump throughout most of his campaign, however.

He deplored the Che Café at UCSD where lots of taxpayer money is being spent to renovate the business and celebrate the mass killer by drinking coffee (which is a carcinogenic substance according to the Californian law but I guess that Che's café may get an exemption). And Keating has also followed me on Twitter so he can't be too left-wing. ;-)

## Monday, April 23, 2018 ... /////

### For SJWs in education, I became a template for villains

Since the February 14th conference, the media have approached the "revolutionary methods to teach" in a somewhat more balanced way – equivalently, a conflict of a sort continued. H-mat.cz is the website promoting Hejný's method or the VOBS method (the acronym means "Education Oriented to the Building of Schemes" in Czech) and they post various press releases.

Several recent press releases are dedicated to the debate about the right ways to teach mathematics.

The newest one reposts some text published in Lidovky, the global pseudointellectuals' preferred daily, on Thursday. The daily chose a following title:

Children have to be pressured to do some math, critics of the playful method claim
LOL, that's a textbook example of a manipulative title. Needless to say, they quote your humble correspondent to justify the title.

## Sunday, April 22, 2018 ... /////

### Brian Keating's Nobel prize obsession surprised me

Brian Keating will release his first book, "Losing the Nobel Prize", on April 24th. I don't own it and I haven't read it. But I was still intrigued by some of the discussions about it.

Backreation wrote a review and Keating responded.

I used to think that the title was just a trick to emphasize the importance of Keating's work: He has done work that could have led to a Nobel prize but Nature wasn't generous enough, it has seemed for some 3 years. But the two articles linked to in the previous paragraph suggest that Keating is much more obsessed with the Nobel prize. That's ironic because the book seems to say that Keating is not obsessed, and he doesn't even want such a lame prize, but it's his colleagues, the spherical bastards, who are obsessed. ;-)

## Saturday, April 21, 2018 ... /////

### Tractor, paint, and what kids should learn about pi

Days ago, Czech kids who are 14-15 years old were trying to pass their high school entry exams designed by CERMAT, a centralized institution producing exams for schools. The most difficult problem was an exercise involving a tractor and a tube of paint in mathematics.

This El Risitas parody got over 100,000 views. El Risitas' German counterpart, Adolf Hitler, was just a little bit less successful.

Zetor Major

The problem is the following:

A tractor ran over a tube of paint. The tube exploded, paint was all around, and the tractor was leaving a mark on the road every 252 centimeters. What is the height of the center of the contaminated tractor's wheel?
Many people who follow the education of mathematics agreed that it was an easy enough, well-chosen, yet "somewhat nontrivial" problem that the good enough kids really should be able to solve. Just to be sure, the solution is $252\,{\rm cm} / 2\pi \approx 40.16\,{\rm cm}$.

Tons of kids whined and claimed that it was harder than a year ago – and it was like a problem in an entry exam for a university. Oh, really?

## Friday, April 20, 2018 ... /////

### Door to door energy vendors: I actually called police

Minutes ago, I called police and complained about the door-to-door energy vendors because among dozens of similar incidents, they were by far the most aggressive ones. I have never had anything resembling a real "argument" with such visitors – and there have been many. I made a search and decided that door-to-door vendors have been banned on the whole territory of Pilsen which is why I reported it.

This approach to "connect to the people" is widespread. Jehovah's Witnesses frequently come in pairs, they ring the bell – outside the building – and they're very pleasant. I have actually allowed them to get in about 10 times in my life, both in the U.S. and in Czechia – the experience was very similar in both countries. Also, some utility and communication companies did the same thing. That's why I switched from ČEZ to Centropol (energy) a few years ago, from O2 to Czech Radiocommunications (later bought by T-Mobile, but now I use the services of UPC) also a few years ago, and so on.

## Thursday, April 19, 2018 ... /////

### A two-hour introduction to the climate change

Last night, I gave a "Science Café" public talk about global warming and climate change and stuff like that (in Czech) which was substantially longer than any previous presentation of mine about the topic – it was something like two hours plus a discussion.

One may talk about lots of the sociology and history of the movement and it's interesting – and often infuriating. But I still think it's more relevant to focus on the hard science and the physical basis of all the phenomena.

## Tuesday, April 17, 2018 ... /////

### Can kids learn to think mathematically from granddaddy's animals?

On Saturday night, we had a reunion – the end of elementary school after 30 years. Lots of beer, memories, personal stuff. I always discuss some serious topics. So one classmate (DS) holds impressive 3 bitcoins and is a full-blown hodler ;-) while your humble correspondent and another classmate (JK) were arguing why the Bitcoin pricing was a bubble and what it meant.

I asked lots of people about Hejný's method to teach mathematics. (Teachers must be silent in the method, kids must invent everything by themselves, they solve some 10+ types of problems in recreational mathematics for 8 years, without any conceptual progress, and at the end, they tell you how much they love and understand mathematics because of this method.) By the end of the exchanges, 10 people were familiar with the topic, 8 of them were familiar to start with. Only 2 were sort of positive about that "constructivist" method in education – and one of them (VK) arguably changed his mind to a large extent. The rest was highly critical, just like I am.

In March, I discussed particular problems, as seen on the matika.in website. All of them are recreational mathematics of some kind and they are supposed to be solved by guesswork – by the trial and error. That brute force strategy is a typical non-mathematical approach to the problems – mathematics is all about searching for patterns and clever things to solve otherwise hard or unsolvable problems.

## Monday, April 16, 2018 ... /////

### Einstein's amateur popularizer in Florida sketched 10D (stringy) spacetime in 1928

Thanks to Willie Soon, Paul Halpern.

St Petersburg Times, Sunday, November 11th, 1928
Guest blog by John Nations, 3141 Twenty-sixth avenue South, City (St. Petersburg), Nov. 9, 1928

Mr Nations played with glimpses of string theory in 1928 and in that year, Lonnie Johnson recorded "Playing with the strings" about that achievement.

Open forum (on the right side from the picture)
UNDERSTANDING EINSTEIN

Editor The Times:

A lot of people believe that Einstein is as transparent as boiler iron, one able authority estimating roughly that at least eight people in the world understand him.

## Sunday, April 15, 2018 ... /////

### Green fanaticism kills, fossil fuels prolong lives

An important pro-gay-marriage New York lawyer David Buckel – who was portrayed in the 1999 movie "Boy's Don't Cry" – committed suicide by self-immolation. In his farewell letter, he claimed that he was blessed to be completely healthy (which we can't properly verify) and the act was done to protest the people's usage of fossil fuels. He prepared a graphic scenery for joggers and bicyclists in a New York park.

First, condolences to his relatives and friends.

Second, regardless of my deep disagreement with everything he wanted to promote, I have respect for a certain kind of courage that is needed for such an act. After all, Jan Palach was a Czech student who protested the 1968 Soviet-led occupation in the same way and I tend to be among those who call him a hero.

Third, this act unmasks the degree of radicalization within the movement that fights global warming. Because the green people are ready to sacrifice their own lives and the benefits seem to be non-existent, we may claim that they are as radicalized as the Islamic suicide attackers.