This Little Book Written In The 2nd Century Makes My Train Ride At 6am A Bit More Bearable And Fun

from letterarii

feeling very normal about this

Karl Schwarzschild

He provided the first exact solution to the Einstein field equations of general relativity, for the limited case of a single spherical non-rotating mass, which he accomplished in 1915, the same year that Einstein first introduced general relativity. The Schwarzschild solution, which makes use of Schwarzschild coordinates and the Schwarzschild metric, leads to a derivation of the Schwarzschild radius, which is the size of the event horizon of a non-rotating black hole.

Schwarzschild accomplished this while serving in the German army during World War I. He died the following year from the autoimmune disease pemphigus, which he developed while at the Russian front. Various forms of the disease particularly affect people of Ashkenazi Jewish origin.

Asteroid 837 Schwarzschild is named in his honour, as is the large crater Schwarzschild, on the far side of the moon. (source) (biography) (more)

Today I found a good video about merging tubes with different angles, ellipses, phase shift of sine waves, featuring sculptures by Frank Smullin.

This video is exceptionally comprehensive.

[Shared by hardm.ix on instagram: Text says: "A little more on the analytic constructivist sculpture of Frank Smullin, a professor of mine at Duke University who combined art and engineering in a way that reminded me a little of Kenneth Snelson and Tensegrity or Buckminster Fuller and geodesic domes."]

A Drop's Shape Effects

Falling raindrops get distorted by the air rushing past them, ultimately breaking large droplets into many smaller ones. This research poster shows how variable this process is by showing two different raindrops, both of the same 8-mm initial diameter.  (Image credit: S. Dighe et al.) Read the full article

Some downloaded files on interesting topics, I keep these in my phone in case I forget my book!