The Great Wall of China, as seen from the space shuttle. Contrary to popular belief, an unaided viewer cannot see it from the moon. One shuttle astronaut said, “We can see things as small as airport runways, [but] the Great Wall is almost invisible from only 180 miles up.” An Apollo astronaut said no human structures were visible at a distance of a few thousand miles. And — most tellingly — Chinese astronaut Yang Liwei couldn’t see it at all.
Incomprehensible math jokes:
Q: What is lavender and commutes?
A: An Abelian semigrape.
Q: What’s yellow, linear, normed, and complete?
A: A Bananach space.
Q: What’s the value of a contour integral around Western Europe?
A: Zero, because all the Poles are in Eastern Europe.
Q: What do you get when you cross a mountain climber with a mosquito?
A. Nothing: you can’t cross a scaler with a vector.
Q: What’s hot, chunky, and acts on a polygon?
A: Dihedral soup.
Q: What sound does a drowning analytic number theorist make?
A: “Log log log log …”
Q: What’s sour, yellow, and equivalent to the axiom of choice?
A: Zorn’s lemon.
“Mathematicians are like Frenchmen,” wrote Goethe. “Whatever you say to them they translate into their own language, and forthwith it is something entirely different.”
Werner Heisenberg gets pulled over for speeding.
The cop says, “Do you know how fast you were going?”
Heisenberg says, “No, but I know where I am.”
a = b
a2 = ab
a2 – b2 = ab – b2
(a – b)(a + b) = b(a – b)
a + b = b
b + b = b
2b = b
2 = 1
Two atoms are walking down the street.
One says, “Wait, I think I lost an electron.”
The other says, “Are you sure?”
The first one says, “Yeah, I’m positive.”
Asteroids named after fictional characters:
Strangely, 2309 Mr. Spock caused an uproar when the asteroid’s discoverer, James Gibson, revealed that he’d actually named it after his cat (he called the cat Spock because it was “imperturbable, logical, intelligent, and had pointed ears”). The International Astronomical Union officially discouraged any more pet animal names, but people are still fine — asteroids have been named after Carlos Santana, Mister Rogers, all four Beatles and all six members of Monty Python.
Proof that one dollar equals one cent:
$1 = 100¢
= (10¢)2
= ($0.10)2
= $0.01
= 1¢
If there are 23 people in a room, then there is a slightly more than 50:50 chance that at least two of them will have the same birthday. For 60 or more people, the probability is greater than 99 percent.
eπ ≅ πe
Yup, that’s a brick.
It’s sitting on Aerogel, “frozen smoke,” the world’s lowest-density solid. The stuff is 99.8% air but can support 2,000 times its own weight, and it holds 15 entries in the Guinness Book of Records.
Most amazingly, it was first created in 1931.