Skip to content

Case Against Cases

April 22, 2015


How to avoid too many cases at least some of the time

Unknown

Theon of Alexandria was history’s main editor of Euclid’s Elements.

Today I want to talk about case analysis proofs.
Read more…

Kinds of Continuity

April 15, 2015


Congratulations to John Nash and Louis Nirenberg on the 2015 Abel Prize

NashNirenberg
Combined from src1, src2.

John Nash and Louis Nirenberg have jointly won the 2015 Abel Prize for their work on partial differential equations (PDEs). They did not write any joint papers, but Nirenberg evidently got Nash excited about David Hilbert’s 19th problem during Nash’s frequent visits to New York University’s Courant Institute in the mid-1950s. Nash in return stimulated Nirenberg by his verbal approach of barraging a problem with off-kilter ideas. The Norwegian Academy of Sciences and Letters recognized their ‘great influence on each other’ in its prize announcement.

Today we congratulate both men on their joint achievement.
Read more…

A Quantum Two-Finger Exercise

April 8, 2015


More mileage than expected from a little example

CarrollBlackboard
Cropped from World Science Festival source

Sean Carroll is a cosmologist in the Department of Physics at Caltech. He also maintains a blog, “Preposterous Universe,” and writes books promoting the public understanding of science. I have recently been enjoying his 2010 book From Eternity to Here: The Quest for the Ultimate Theory of Time.

Today—yes, Carroll would agree that there is a today—I would like to share an interpretation of a little quantum computing example that occurred to me while reading his book.
Read more…

April Fool

April 1, 2015


Non-jokes on April Fool’s Day

nunspriest
Nun’s Priest’s Tale source

Faadosly Polir is the older brother of Lofa Polir. You may recall he invented new ways to apply powerful mathematical techniques to prove trivial theorems, and she once claimed a great result on integer factoring. We have heard from both since, but they haven’t given us any new April Fool’s Day material, mainly because they weren’t fooling to begin with.

Today Ken and I wished to help you enjoy April Fool’s day.
Read more…

Is It New?

March 24, 2015


How to tell algorithms apart

egdaylightSummerPic

Edgar Daylight was trained both as a computer scientist and as a historian. He writes a historical blog themed for his near-namesake Edsger Dijkstra, titled, “Dijkstra’s Rallying Cry for Generalization.” He is a co-author with Don Knuth of the 2014 book: Algorithmic Barriers Failing: P=NP?, which consists of a series of interviews of Knuth, extending their first book in 2013.

Today I wish to talk about this book, focusing on one aspect.
Read more…

Leprechauns Will Find You

March 17, 2015

And perhaps even find your hidden prime factors

 

leprechaun_256

Neil L. is a Leprechaun. He has visited me every St. Patrick’s Day since I began the blog in 2009. In fact he visited me every St. Patrick’s Day before then, but I never talked about him. Sometimes he comes after midnight the night before, or falls asleep on my sofa waiting for me to rise. But this time there was no sign of him as I came back from a long day of teaching and meetings and went out again for errands.

Today Ken and I wish you all a Happy St. Patrick’s Day, and I am glad to report that Neil did find me.
Read more…

The Other Pi Day

March 14, 2015


It’s 3/14/15, do you know how much your Π costs?

pi-tag-usa-artikel-410
source

Larry Shaw apparently created the concept of Pi Day in 1988. He was then a physicist who worked at the San Francisco Exploratorium. He and his colleagues initially celebrated by marching around in circles, and then eating pies—that is fruit pies. As Homer Simpson would say: hmm.

Today Ken and I want to add to some of the fun of Pi Day, and come back to a different Pi that has occupied us.
Read more…

Follow

Get every new post delivered to your Inbox.

Join 2,532 other followers