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From Computational Complexity

A(nother) nice use of Gen Functions

In a prior post I tried to give a simple example of a proof that uses Gen Functions where there was no other way to do it. For better or worse, before I posted...

From Computational Complexity

DUMP YOUR TABLES! (the moral of my story that started with a hat problem)

Recall from my last post: PROBLEM 1: There are n people sitting on chairs in a row. Call them p1,...,pn. They will soon have HATS put on their heads, RED or BLUE...

From Computational Complexity

A problem and later a story and a point.

I have (1) a math problem to tell you about (though I suspect many readers already know it), (2) a story about it, and (3) a point to make. TODAY I'll just do the...

From Computational Complexity

Combinatorics use to not get any respect. But because of Erdos...

(This blog is based on things I heard at the Erdos 100th Bday Conference) I have spend the last week at the Erdos 100th bday conference. One point that was made...

From Computational Complexity

Quantum Tecniques/Gen Functions- don't be afraid of new techniques

Ronald de Wolf gave a GREAT talk at CCC on the uses of Quantum techniques to Classical Problems. He made the analogy of using the Prob Method to prove non-prob...

From Computational Complexity

Fraud or not ?

For each of these, are they frauds? The Turk was a chess playing ``computer'' (around 1770) that was later discovered to be cheating--- a human made the moves...

From Computational Complexity

STOC: Some NON-radical ideas

At the STOC business meeting Joan Feigenbaum (PC chair) raised some very good points. There was no real discussion (or perhaps the burning car was the discussion)...

From Computational Complexity

Do you KNOW how you KNOW what you KNOW? I don't KNOW.

When watching Jeopardy with Darling if I get a question correct that is NOT in my usual store of knowledge (that is NOT Ramsey Theory, NOT Vice Presidents, NOTHow...

From Computational Complexity

Mother's Day Math

Problem: On Mothers day (May 12 this year) restaurants are very crowded because many people take their mothers, grandmothers, great-grandmothers, etc out to lunch...

From Computational Complexity

Are you smarter than a fifth grader? I'm not.

My darling sometimes watches TV in the middle of the night when she can't sleep.So I found myself watching (actually listening) to the quiz show Are You Smarter...

From Computational Complexity

Computer Assisted Proofs- still controversial?

Kenneth Appel, of Appel-Haken Four Color Theorem Fame, died recently. See here for an obit. In 1972 I read that the four-color theorem was an open problem.here...

From Computational Complexity

Oh, I remember/recorded/DVRed it well

You can now wear a device, Memoto that will take a picture every 30 seconds. Do you really have a Kodak Moment every 30 seconds? No, but this way when you do have...

From Computational Complexity

Post Mordem on an April Fool's day joke

Recall that on April Fools Day I had a post about R(5) being discovered via a collaboration of Math and History. Many readers emailed me asking how many people...

From Computational Complexity

You should apply for STOC and/or CCC travel money (students)

Once again there is some money from ACM and from NSF for students to goto STOC, and I am the one to send the applications to. The link for info on how to apply...

From Computational Complexity

Is the rule of threes a meta-urban legend?

Roger Ebert died on April 4, 2013 Margaret Thatcher died on April 8, 2013. I have heard the urban legend that celebrities die in threes. Does anyone really believe...

From Computational Complexity

A nice case of interdisciplinary research

All of the math and history in this post is elaborated on in my paper here. Are there any interesting applications of PURE math to the Social Sciences or History...

From Computational Complexity

Counting Descriptions- a ``new'' complexity class

Let nσ(w) is the number of σ's in w. We often ask our students about languages like { w | na(w) = 2nb(w) } (CFL but not REG). Lets formally define languages that...

From Computational Complexity

Will they use EasyPope to pick the Pope in 2050?

AP press 2050: The new pope was elected in just 2 hours using EasyPope, the software based on EasyChair, software designed to deciding which papers get into a conference...

From Computational Complexity

What if they gave an exam and nobody came?

A professor tells the class that he will use the highest grade to set the curve. The students all conspire to NOT take the exam, so the highest score is 0, so they...

From Computational Complexity

Do we ever NEED the adv pumping lemma for Reg langs?

Recall the Pumping Lemma and the Advanced Pumping Lemma for Regular languages: Pump. Lemma: If L is regular and infinite then there exists n such that for all...
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