A note from our fearless leader Peter Andrews:

If you have been in the lounge this morning you will have seen the bread
laid out on the table as a reminder that our end-of-term party is coming
up this afternoon. I hope you will all be able to come by for at least
a short while and preferably a long while!

As you probably know, Bert Reed and Greg Ronsse are both retiring at the
end of this term. Greg has stated publicly that he will be back a few times
in the spring and that he would rather we held any formal recognition until
sometime in the spring. I'll keep you posted.

If there are any others of you planning to retire in the next 3 weeks,
please let me know!!

Take a whiff of the bread and come by the center tower at 4:00 to sample
each loaf -- and then some!!

Thanks for another term -- furlough free!! Happy Finals, Happy Grading,
and finally Happy Holidays.

Anyone within the sound of this message is invited to attend.

James Garfield's Proof of the Pythagorean Theorem

James Garfield, the 20th President of the United States, gave the following simple proof of the Pythagorean theorem



It begins by constructing the trapezoid with parallel sides of height a and b and with base a + b. The area is given by the base times the average height or

A = (1/2)(a+b)².

On the other hand, we may compute the area of the three nonintersecting interior (and necessarily right) triangles

A = (1/2)(ab + ab + c²),

where c is the hypotenuse.
Setting up the equation for the two equal area calculations we have


(1/2)(a² + 2 a b + b²) = (1/2)(2 a b + c²),

or
a² + b² = c².

Yevgenia Movshovich to Give December 4th Colloquium

Yevgenia Movshovich will give the final coloquium of the semester today.

A pdf abstract can be found on the department website
The talk will concern positive harmonic functions on Dirichlet domains.