Matt Ridley’s Thesis: When Ideas Have Sex

Watched When ideas have sex by Matt Ridley from
At TEDGlobal 2010, author Matt Ridley shows how, throughout history, the engine of human progress has been the meeting and mating of ideas to make new ideas. It's not important how clever individuals are, he says; what really matters is how smart the collective brain is.
When extrapolated a bit, this thesis is one of the best arguments for why Twitter and other methods of social media are so useful.  There really is a great idea at the core of this presentation.

Paul Halmos on Prerequisites

Definitely the quote of the day:

Paul Halmos (1916 – 2006, Hungarian-born American mathematician
in Measure Theory (1950)


This is essentially the mathematician’s equivalent of the adage “Fake it ’til you make it.”

Nicholas Bourbaki and Serge Lang

Replied to Scientific Fiction – The Bourbaki Mystery by Sue Vazakas (The Sheridan Libraries Blog)

In the 1930s, a French mathematician began writing journal articles and books. His name was Nicolas Bourbaki. He didn’t exist.

Bourbaki was and is actually a group of brilliant and influential mathematicians, mostly French but not all, whose membership changes but whose collective purpose remains the same: to write about mathematical topics they deem important. Between 1939 and 1967 “he” wrote a series of influential books about these selected topics, collectively called Elements of Mathematics.

A mysterious, mostly anonymous group of writers publishing momentous things under a single name is just really cool. But don’t try to read any of his stuff unless you are an expert mathematician.

Instead, read a wonderful story by novelist and award-winning chemist Carl Djerassi, called The Bourbaki Gambit. What do you think happens when a group of scientists, being discriminated against for various reasons, team up and use the “Bourbaki” approach to try to get their latest discovery taken seriously?

There’s an old mathematicians’ joke that goes like this:

Q: When did Nicholas Bourbaki quit writing books about mathematics?

A: When (t)he(y) realized that Serge Lang was only one person!

Global classical solutions of the Boltzmann equation with long-range interactions

Bookmarked Global classical solutions of the Boltzmann equation with long-range interactions (
Finally, after 140 years, Robert Strain and Philip Gressman at the University of Pennsylvania have found a mathematical proof of Boltzmann’s equation, which predicts the motion of gas molecules.


This is a brief announcement of our recent proof of global existence and rapid decay to equilibrium of classical solutions to the Boltzmann equation without any angular cutoff, that is, for long-range interactions. We consider perturbations of the Maxwellian equilibrium states and include the physical cross-sections arising from an inverse-power intermolecular potential r-(p-1) with p > 2, and more generally. We present here a mathematical framework for unique global in time solutions for all of these potentials. We consider it remarkable that this equation, derived by Boltzmann (1) in 1872 and Maxwell (2) in 1867, grants a basic example where a range of geometric fractional derivatives occur in a physical model of the natural world. Our methods provide a new understanding of the effects due to grazing collisions.



In Law Schools, Grades Go Up, Just Like That

Bookmarked In Law Schools, Grades Go Up, Just Like That (New York Times)
In the last two years, at least 10 law schools have made their grading systems more lenient to give their students a better chance in a soft job market.

Is GPA tampering and grade inflation going too far with changes like this?

First U.S. stem cells transplanted into spinal cord |

Bookmarked First U.S. stem cells transplanted into spinal cord by Miriam Falco, CNN Medical News Managing Editor (
For the first time in the United States, stem cells have been directly injected into the spinal cord of a patient, researchers announced Thursday.
A recent article announcing the first stem cells being transplanted into a human patient in the United States. I worked with the researchers and surgeon in this experiment and built the microinjectors that were used in the lead up experiments as well as for this first patient.

Twitter Changes Rules on Users. No Auto-Follow. | Kyle Lacy

Replied to Twitter Changes Rules on Users. No Auto-Follow. by Kyle Lacy (
(hat tip to ZDNEt and Chris McEvoy for the lead) From ZDNet: “With no notice, Twitter yesterday “pulled the rug out from under its developers” one developer says, by discouraging auto-following and imposing 1,000 person-per-day following limits.” Now… this is not news to me because of the “pulling the rug out from under its developers” thing or the 1,000 person-per-day following limit… The news to me as a Twitter user… I don’t really remember getting a message or alert that the new limits were going to be enacted. I use Twitter on a daily basis. It seems fairly odd that I would not know about the change.
I’m personally glad they’d be implementing something like this and wish they had done it about a month ago. Eventually without any controls the site would have become a waste land. In the spirit of using it as the tool it has become, they needed to implement changes like this as the site scaled up to more and more people. It’s very similar to the changes they instituted in the fall of 2008 when they created a cap of being able to follow more than 2000 people when your own number of followers wasn’t commensurate with that number. As a game theorist, I’m sure that people will somehow find some other way to artificially game the system.

As a separate note, who really wants to waste the time building thousands and thousands of followers when none of them are really going to ever pay attention to you? Yes, it’s great to have a high number, but really what is your ultimate reach? How many people are you engaging?

Bookmarked The structure of degradable quantum channels by Toby S. Cubitt, Mary Beth Ruskai, Graeme Smith (Journal of Mathematical Physics 49, 102104 (2008))
Degradable quantum channels are among the only channels whose quantum and private classical capacities are known. As such, determining the structure of these channels is a pressing open question in quantum information theory. We give a comprehensive review of what is currently known about the structure of degradable quantum channels, including a number of new results as well as alternate proofs of some known results. In the case of qubits, we provide a complete characterization of all degradable channels with two dimensional output, give a new proof that a qubit channel with two Kraus operators is either degradable or anti-degradable, and present a complete description of anti-degradable unital qubit channels with a new proof. For higher output dimensions we explore the relationship between the output and environment dimensions (dB and dE, respectively) of degradable channels. For several broad classes of channels we show that they can be modeled with an environment that is “small” in the sense of ΦC. Such channels include all those with qubit or qutrit output, those that map some pure state to an output with full rank, and all those which can be represented using simultaneously diagonal Kraus operators, even in a non-orthogonal basis. Perhaps surprisingly, we also present examples of degradable channels with “large” environments, in the sense that the minimal dimension dE>dB. Indeed, one can have dE>14d2B. These examples can also be used to give a negative answer to the question of whether additivity of the coherent information is helpful for establishing additivity for the Holevo capacity of a pair of channels. In the case of channels with diagonal Kraus operators, we describe the subclasses that are complements of entanglement breaking channels. We also obtain a number of results for channels in the convex hull of conjugations with generalized Pauli matrices. However, a number of open questions remain about these channels and the more general case of random unitary channels.
Alternate version on arXiv: 

📅 DrupalCampLA | September 13-14, 2008

RSVPed Attending BarCamp / DrupalCampLA
Dates: September 13-14, 2008; 10am - 6pm, both days Los Angeles Convention Center, 1201 South Figueroa Street Los Angeles, California 90015 Still FREE Registration is Open until September 10th, 2008. Please visit our official site for more details and to sign up!

PESOS post from Lanyrd prior to its shutdown.

Bookmarked Automated on-chip rapid microscopy, phenotyping and sorting of C. elegans. by Kwanghun Chung, Matthew M. Crane, Hang Lu (Nature Methods [22 Jun 2008, 5(7):637-643])
Microscopy, phenotyping and visual screens are frequently applied to model organisms in combination with genetics. Although widely used, these techniques for multicellular organisms have mostly remained manual and low-throughput. Here we report the complete automation of sample handling, high-resolution microscopy, phenotyping and sorting of Caenorhabditis elegans. The engineered microfluidic system, coupled with customized software, has enabled high-throughput, high-resolution microscopy and sorting with no human intervention and may be combined with any microscopy setup. The microchip is capable of robust local temperature control, self-regulated sample-loading and automatic sample-positioning, while the integrated software performs imaging and classification of worms based on morphological and intensity features. We demonstrate the ability to perform sensitive and quantitative screens based on cellular and subcellular phenotypes with over 95% accuracy per round and a rate of several hundred worms per hour. Screening time can be reduced by orders of magnitude; moreover, screening is completely automated.