April 4: Combs and Cowlicks

Today's tidbit is about something in mathematics called the "Hairy  Ball Theorem."  No, it's not what you are thinking about, but yes, it  does apply to what you are thinking about.

April 4 is the birthday of the mathematician Hopf, who is known for a  result called the Poincare-Hopf Theorem, an example of which is the  hairy ball theorem.  It says that if you have a hairy ball (like a  really fuzzy tennis ball) and you try to comb it flat, you will always  leave a cowlick or tuft of hair at one end; you cannot have all the  hairs lay flat.

April 11: Boring?

On April 11, 1905, Albert Einstein published his special
theory of relativity.  In 1814, Napolean was exiled to Elba.  In 1888,
one of the great orchestras of the world, the Concertgebouw in
Amsterdam, was established.

Now here is the interesting bit: by searching for news events, it was
claimed that April 11, 1954 was the most boring day of the 20th
century.  A team of scientists at Cambridge University scoured through
300 million news stories to find the day with the least number of
newsworthy events.

May 6: Soaring above the wing

May 6 is an interesting date in history, lots of stuff happened:
--It was the last day  of the second world war (the documents ending the war were signed on May 7)
--The Hindenberg exploded in 1937
--Roger Bannister ran a mile under 4 minutes
--The Eiffel Tower was first opened to the public.  Gustave Eiffel's company designed and built the tower.  Eiffel was also involved in building the Statue of Liberty.  He built many bridges all over the world, and was involved in an early attempt to build the Panama Canal.  That effort failed, and after that, he "quit engineering" and devoted himself to aerodynamics. Now comes the cool part: he built a wind tunnel in 1909 and made a big discovery: that lift (produced by an airfoil/airplane wing) was not caused by an increase of pressure under the wing but instead was due to a reduction of pressure above the wing.  For this, he was awarded the James Langley medal by the Smithsonian in 1913.