Saturday, February 17, 2018

Cool Integral

From KarlMagnus Petersson‏ on Twitter:


In the same way, you can show (I think) that


which is also cool, but not as cool, since "3" is not as cool as "e."

Note: 1/3 < 1/e. This makes sense, since for 0 < x <1, sqrt(x) < cuberoot(x) < fourthroot(x), etc.

Note II: Speaking of e, one of my best friends, a colleague in graduate school (we had the same advisor, and have gotten even closer since), once wrote a paper that contained the number e^e, which I think is about the coolest thing ever published in physics. I wrote about it here for Physics World.

Wednesday, February 07, 2018

Global Warming in Ursula Le Guin's 1969 Novel "The Left Hand of Darkness"

The science fiction writer Ursula Le Guin recently died (she lived in Portland, Oregon for decades), and since I hadn't read anything by her I thought I better get started. So I picked The Left Hand of Darkness, her breakthrough book published in 1969. She was on the ball, because even then she knew about CO2 and global warming. Here she writes about her fictional planet of Gethen.
Eskichwe rem ir Her hypothesized that the volcanic activity in N.W. Orgoreyn and the Archipelago has been increasing during the last ten or twenty millennia, and presages the end of the Ice, or at least a recession of it and an interglacial period. CO2 released by the volcanoes into the atmosphere will in time serve as an insulator, holding in the longwave heat-energy reflected from the earth, while permitting direct solar heat to enter undiminished. The average world temperature, he says, would in the end be raised some thirty degrees, till it attains 72°. I am glad I shall not be present. Ai says that similar theories have been propounded by Terran scholars to explain the still incomplete recession of their last Age of Ice. All such theories remain largely irrefutable and unprovable; no one knows certainly why the ice comes, why it goes. The Snow of Ignorance remains untrodden.
It's interesting that she associated CO2 warming with the Ice Ages, as science did for a good while back then, I think, while it grappled with understanding the Pleistocene.

More Humor from SpaceX

(Besides the orbiting red roadster, I mean)

Saturday, February 03, 2018