acm-header
Sign In

Communications of the ACM

Blogroll


bg-corner

From Computational Complexity

The two defintions of Chomsky Normal Form

I have eight  textbooks on Formal Lang Theory on my desk.  Six of them define a CFG to be in Chomsky Normal Form if every production is of the form either A-->BC...

From Computational Complexity

Barrier's for Matrx Mult Lower bound

Matrix Mult: The usual algorithm is O(n^3). Strassen surprised people by showing an O(n^{2.81}) algorithm. (Now its so well known that its not surprising. IFast...

From Computational Complexity

Why do students do this?

Before my midterm in ugrad  Theory of Computation  I gave the students a sheet of practice problems to do that I would go over before the midterm. One of them...

From Computational Complexity

Joint Center for Quantum Information and Computer Science

(Guest post by Andrew Childs who is now at the Univ of MD at College Park) We have recently launched a new Joint Center for Quantum Information and ComputerScience...

From Computational Complexity

Godel and Knuth Prize Nominations due soon. Which would you rather win? Or ...

(Alg Decision Theory conference in Kentucky: here.) Knuth Prize Nominations are due Jan 20, 2015. For info on the prize see here, if you want to nominate someone...

From Computational Complexity

Cliques are nasty but Cliques are nastier

BILL: Today we will show that finding large cliques is likely a nasty problem STUDENT: Yes! In my High School the Cliques were usually at most six people and they...

From Computational Complexity

Guest Post about Barbie `I can be an engineer' -- Sounds good but its not.

There is now a I can be an engineer Barbie. That sounds good! It's not. Imagine how this could be turned around and made sexist. What you are imagining might not...

From Computational Complexity

A Fly on the wall for a Harvard Faculty meeting: Not interesting for Gossip but interesting for a more important reason

I was recently in Boston for Mikefest (which Lance talked about  here)  and found time to talk to  my adviser Harry Lewis at Harvard (adviser? Gee, I already finished...

From Computational Complexity

Non controversial thoughts on rankings

US News has a ranking of CS depts and various subcategories. Recently MohammadTaghi Hajiaghay and Luca Trevisan have suggested alternative rankings here (Moh) and...

From Computational Complexity

A few more notes about Sipser and Sipser-60th

While Lance was AT Mikefest (Sipser's 60th Bday conference), helping to organize it, emceeing the personal statements, I was... also there. A few notes Aside...

From Computational Complexity

Guest Post by Dr. Hajiaghayi: A new way to rank departments

(This is a guest post by MohammadTaghi Hajiaghayi. His name is not a typo- the first name really is MohammadTaghi.) Due to our belief in the lack of transparency...

From Computational Complexity

Martin Gardner Centennial

Martin Gardner was born on October 21, 1914, so today is his Centennial (he died on May 22, 2010, at the age of 95). We've mentioned him in the blog before:  ...

From Computational Complexity

Algorithms that never get coded up

(There was a passing ref to this topic in the comments to one of Scott's blogs, so I thought I would pick up the theme.) When I teach Formal Lang Theory I endCould...

From Computational Complexity

Luddite or not?

My first ever guest post for Lance was on Are you a luddite. I certainly am to some extent a luddite, but there are some things where it not clear if they are luddite...

From Computational Complexity

The Complexity of NIM. Open?

Recall 1-pile NIM: Let A be a finite set of Naturals. NIM(A) is the following game: There are n stones on the board. Players I and II alternate removing a\in A...

From Computational Complexity

Dagstuhl on Algebra in Computational Complexity

(Reminder- Theory day at UMCP: here is the link. ) There was a Dagstuhl on Algebra in Computational Complexity Sept 22-26. I learned stuff in the talks, over meals...

From Computational Complexity

Gentry and Lurie and Zhang can say they are genius's without bragin'- MacArthur Genius's

(If I mispell anything in this post, well, that"s why I'm not a MacArthur Genius, or any other kind of Genius.) Craig Gentry, of homomorphic encryption fame, won...

From Computational Complexity

Maryland Theory Day October 10!

Univ of Maryland at College Park is having a Theory Day Friday October 10. Free Registration and Free Lunch! (there are no economists coming to tell us therehere...

From Computational Complexity

A Statistical oddity ?

 I keep a list of people that are famous-to-me  that are old so that if someone dies I won't be surprised. When Lauren Bacall died  recently I  (1) knew who she...

From Computational Complexity

How hard is changing fields? Ask Sheldon!

In the last season of  The Big Band Theory Sheldon wants to change field from String theory to something else (I don't recall if he settled on what it would be,...
Sign In for Full Access
» Forgot Password? » Create an ACM Web Account