Sign In

Communications of the ACM

Blogroll



From Computational Complexity

Presidential Quiz: Three ways to take it

 Every four years around the time of the inaugural I post a presidential Quiz! I do that today, and I will post the answers on Monday.  I am tempted to joke that...

From Computational Complexity

The ACM History Committee call for proposals looks wrong

 In November I (and prob everyone in the ACM) got an email that was a call for proposal from the ACM History committee. Here is a pointer to it. One of the passages...

From Computational Complexity

My Survey on Hilbert's 10th for particular (d,n) is ready for you to help me on!

 Hilbert's 10th problem is  (in modern terminology) to find an algorithm that will, given a poly p(x1,...,xn) in Z[x1,...,xn], determine if it has a solution in...

From Computational Complexity

Dr Jill Biden

(I was helped on this post by Gorjan Alagic, Andrew Childs,  Tom Goldstein, Daniel Gottsman, Clyde Kruskal,  Jon Katz. I emailed them for their thoughts on thehere...

From Computational Complexity

Quarterly Th. Wksp `at' Northwestern, and thoughts inspired by it

 On the Northwestern CS Theory Group there is a set of Quarterly Theory Workshops. There is one coming up on Dec 17-18, 2020, called the Junior Theorists Workshop...

From Computational Complexity

In 1974 Planarity was O(V) time and could do 900 node graphs in 12 seconds! Fast then...

In 1974  Hopcroft and Tarjan showed that Planarity is in polynomial time. That is an understatement- they actually have an O(V) algorithm which one can actually...

From Computational Complexity

James Randi, Magicians-Author-Skeptic, passed away at the age of 92

James The Amazing Randi died on October 20, 2020, at the age of 92. He is survived byhis husband Jose Alvarez.  His Wikipedia page is here A few Randi Points: 0)...

From Computational Complexity

Fun with birthdays, inspired by Nov 20

 On Nov 20, 2020  the Google Doodle was of Benoit Mandelbrot for his 96th birthday. Why have a Doodle on his 96th bday? Anyway, the Doodle is here.  On Nov 20,here...

From Computational Complexity

Alex Trebek/What is today's post about?

 Alex Trebek, long time host of the TV show Jeopardy! (the exclamation point is part of the name, though I will omit it for the rest of the post), passed away in...

From Computational Complexity

Random Thoughts on the Election (2020)

1) Biden will be the oldest president (measuring by when they take the oath of office), at 78. The next two are Trump 70 and Reagan 69. Biden will be older entering...

From Computational Complexity

I polled my class about the election

 In 2016 I had the Sophomore discrete math class do a poll of who they wanted for president.In 2020 I had the  both my  Senior Crypto class and Clyde's Sophomore...

From Computational Complexity

Do not become obsessed with the Polls unless...

I know someone who checks the polls 3 times a day to see who looks like they will be elected prez. She cares A LOT about the election. It is irrelevant to this...

From Computational Complexity

Nature vs Nurture close to my birthday

 Since I was born on Oct 1, 1960 (that's not true---if I posted  my real birthday I might get my  identity stolen), I will do a nature vs nurture post based onhere...

From Computational Complexity

Hugh Woodin, Kurt Godel, Dwayne `The Rock' Johnson, Robert De Niro, David Frum, Tom Selleck: Do I care what they think? Should I?

 MATH:My last post on CH mentioned that Hugh Woodin used to think NOT(CH) but now thinks CH. In both cases his reasons have some math content to them. Also, note...

From Computational Complexity

Revisiting the Continuum Hypothesis

I have been thinking about CH lately for two reasons1) I reread the articleHilbert's First Problem: The Continuum Hypothesis by Donald Martin from Proceedings of...

From Computational Complexity

A Quote from Testla which is very predictive in one way, and perhaps not in another way

 Nikola Testla, famous inventor, who lived 1856--1943 said the following:When wireless is perfectly applied the whole earth will be converted intoa huge brain,...

From Computational Complexity

Baseball can go on forever, it doesn't just seem that way

 Most games have some way to make sure they cannot go on forever.1) Chess: I had thought there was a 50-move rule and a 3-times-same-position rule, but its a byte...

From Computational Complexity

An interesting serendipitous number

 Last seek I blogged about two math problems of interest to me here.One of them two people posted answers, which was great since I didn't know how to solve them...

From Computational Complexity

When are both x^2+3y and y^2+3y both squares, and a more general question

 In my last post (see here) I asked two math questions. In this post I discuss one of them. (I will discuss the other one later, probably Monday Sept 14.)For which...

From Computational Complexity

Two Math Problems of interest (at least to me)

 I will give two math problems that are of interest to me.These are not new problems, however you will have more fun if you work on them yourself and leave comments...
Sign In for Full Access
» Forgot Password? » Create an ACM Web Account