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From Computational Complexity

Why does pi come up so often? I don't know either but ...

 Here is how history DID unfold:1) People noticed that the ratio of the circumference to the diameter of ANY circle is always the same, it's a number between 3this...

From Computational Complexity

The Betty White Award for 2022

In Dec 2021 I noted in this post, which was my 1000th post ever (according to Ken Regan, see here) that Betty White had the misfortune of dying on Dec 31, 2021,...

From Computational Complexity

ChatGPT tried to write an obit for Martin Davis. What it got right, wrong, and what to make of it.

When Martin Davis passed away Lance emailed me what he got from using ChatGPT to do an obit. Here it is and I also note what it got wrong.----------------------...

From Computational Complexity

Martin Davis Passed Away on Jan 1, 2023

As you probably already know from other sources, Martin Davis passed away on Jan 1, 2023, at the age of 94. His wife Virginia died a few hours later.He majoredOccasionally...

From Computational Complexity

Voter Suppression, Harvard Style

The following appeared on Harry Lewis's blog, here, hence it is written in his voice, though it is a co-authored. You'll see why later.  I then have some comments...

From Computational Complexity

Commercials are not logical. FTX edition.

Some people asked me to comment on FTX since I teach Crypto. My insights are no better than anyone else; however, I have wanted to do a blog post about the illogic...

From Computational Complexity

Harry Lewis's talk on The Birth of Binary on Dec 8 (Thats today!)

 More on the information on Harry Lewis's  talk is in his blog post about it:here1) On Dec 8, 2022 Harry Lewis is giving the annual Thoraf Skolem Memorial Lecture...

From Computational Complexity

Would you be more productive if you didn't log on? It worked for Christopher Havens!

There are times when NOT having computer access (is that possible anymore?) can make you MORE productive. 1) I did a lot of my Muffin Work when I was in MexicoTexas...

From Computational Complexity

Who first thought of the notion of Polynomial Time?

(Updated version of  Computational Intractability: A Guide to Algorithmic Lower Bound by Demaine-Gasarch-Hajiaghayi is here)Any question like who first though of...

From Computational Complexity

Euclidean TSP is NP-hard but not known to be in NP. Why not known?

BILL: Lance, I was looking into TSP, metric TSP, Euclidean TSP since I am going to teach about P, NP, NPC, and approximating NPC problems and I came across theThe...

From Computational Complexity

Does the Physics Nobel Prize Winner understand their own work (guest post)

 David Marcus was a Math major a year ahead of my at SUNY Stonybrook (he graduated in 1979,I graduated in 1980). He then got a PhD from MIT in Math, and is a reader...

From Computational Complexity

The Media Coverage of the Matrix result is Terrible (though not worse than usual)

 BILL: A computer program (or an AI or an ML or whatever) found a BETTER way to do matrix mult! Its in the same spirit as Strassen. I've always wondered if Strassen...

From Computational Complexity

BYTE LYNX- an awesome video game/Am I an influencer?

Tucker Bane is a friend of mine who has an AWESOME video game availablethat is called BYTE LYNX.I am curious- Can I be an INFLUENCER!Lets find out!At the link below...

From Computational Complexity

Will Strassen's Matrix Mult Alg ever be practical?

All time bounds are asymptotic and really O-of.Recall that Strassen found a clever way to multiple two 2x2 matrices with 7 mults (and lots of adds)  leading tohere...

From Computational Complexity

Is it okay for a paper or book to say `for more on this topic see Wikipedia Entry BLAH.

 One of the proofreaders for Computational Intractability: A Guide to Algorithmic Lower Bounds(available here)made the following objection, which raises some questions...

From Computational Complexity

Is the complexity of approximating Vertex Cover of degree 3 open?

 RECALL:A max-problem f has a A P Time App Scheme (PTAS) if there is an algorithm ALG such that ALG(\epsilon) \ge (1-\epsilon)f(x).A min-problem f has a A P Time...

From Computational Complexity

POSTED UPDATED VERSION OF Computers and Intractability: A guide to Algorithmic Lower Bounds posted (New title)

We have posted a revised version of Computational Intractability: A Guide to Algorithmic Lower Boundsby Demaine-Gasarch-HajiaghayiThe book is here.(For the original...

From Computational Complexity

There are two different definitions of Integer Programming. Why?

Alice and Bob have the following conversation.===============================ALICE: In your book you define INT PROG as, given a matrix A and vectors b,c,find the...

From Computational Complexity

Monarachy: A Problem with Definitions

 As I am sure you know, Queen Elizabeth II passed away at the age of 96 recently.  I am not a royal-watcher, but I am a royal-watcher-watcher. That is, the question...

From Computational Complexity

Computers and Intractability: A Guide to Algorithmic Lower Bounds. First draft available! Comments Welcome!

(This post is written by Erik Demaine, William Gasarch, and Mohammad Hajiaghayi)In 1979 Garey and Johnson published the classic        Computers and Intractability...
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