## Sixth Linkfest

This weekend I attended the Midwest Model Theory Conference right here at Ohio State University. Everybody gave really awesome talks (I would have given one, but model theory isn’t my specialty). I was glad to meet a lot of different mathematicians. It was interesting listening to senior logicians discussing foundational issues of mathematics with each other. There was some overlap with the graduate student logic conference I attended a couple weeks ago in Chicago, and it was great to “follow up” with some of the folks I’d met there (and return the favor of hosting).

Doing these linkfests is sort of cathartic. Like reading notes before class is beneficial, so too is “reviewing” articles I’ve read over the past couple weeks, after my mind has had a chance to sleep on them a bit. Today I was totally exhausted after a four hour teaching-and-tutoring spree, and it was good to have something like this to preoccupy me. I’m a bit more rested now, and should be able to get on with my research. Meanwhile, I hope you like this fortnight’s batch of links!

The previous linkfest was Linkfest 5.

## Technical

Ngô Quốc Anh: The Nehari manifold

John Armstrong: Another Existence Proof (of the convergence of the Picard iteration), Gronwall’s Inequality, Lie Algebras

Jeremy Avigad: Uncomputably noisy ergodic limits (PDF)

Bati: Exchangeable Random Partitions, Fundamental Theorem of Algebra and Brownian Motion, Von Neumann’s proof of Radon-Nikodym

Alexandre Borovik: Infinity in Haskell, Prime Numbers and the Periodic Table

Lieven le Bruyn: What have quivers done to students?, Who dreamed up the primes=knots analogy?, Penrose tilings and noncommutative geometry

Ryan Budney: MO-problems: codimension zero embeddings

David Corfield: Making Things Simpler by Duality

Joel Hamkins, David Linetsky and Jonas Reitz: Pointwise Definable Models of Set Theory

Hilbertthm90: Heights of p-divisible Groups, Hodge and de Rham Cohomology Revisited, Problems with de Rham and l-adic cohomology

JSE: Maples on Cohen-Lenstra for matrices with iid entries

Tanya Khovanova and Alex Ryba: Enemies and Friends (a problem from the Gillis Math Olympiad)

Emmanuel Kowalski: Subtile finesse de la notation…

Dick Lipton: A Possible Polymath Project? (on a problem of Erdős about colorings), Close Encounters of the Proof Kind, More On Coloring The Plane

Akhil Mathew: Formal smoothness, The cotangent complex I: group objects in categories of algebras

George Metcalfe and Nicola Olivetti: Towards a Proof Theory of Gödel Modal Logics (PDF)

Daniel Moskovich: In search of the best Mapping Class Group presentation- Part I

Terence Tao: Stein’s maximal principle, Stein’s spherical maximal theorem, Locally compact topological vector spaces

Willie Wong: Decay of waves IIa: Minkowski background, homogeneous case

## Non-Technical

Alexandre Borovik: Time Lag in Learning Mathematics

Matthew Belinkie: Eurovision 2011: The Big Five Preview, Clichemageddon 3D

Kareem Carr: (Preparing for) The Unexpected

Nathan Eady: Rejected Ideas for Library Summer Reading Promotional Themes

Barbara Edwards and Michael Ward: Surprises from Mathematics Education Research: Student (Mis)use of Mathematical Definitions (PDF)

John Ewing: Mathematical Intimidation: Driven by the Data (PDF)

Lance Fortnow: Cell Phones versus Drunk Driving

William Gasarch feat. Lauren Cowles: On demand Publishing (of paper books)

Forrest Higgs: Winding up the (reprap) String Wars

Lorne Kates: The Might of the PEN

Tanya Khovanova: The Hidden Agenda Revealed

Mark Lee: Statistical Analysis of Movie Title Lengths

Luke O’Neil: Wtf does a moderately successful rockstar do all day?

Orchid64: Will Miss #318: laughing in all the “wrong” places

Alex Papadimoulis: Faulty by Design, The Special Test Page, The Brains of the Operation

The Physicist: Q: If we meet aliens, will they have the same math and physics that we do?

Adriana Salerno: Discovering the Small-World Network (or: getting a job at a small liberal arts school after getting used to big research universities)

Sonic Charmer: The Most Annoying Scene In The Action Movie, Wrong Kind of Argument pt. 2 (or: a baseball card analogy to argue against Krugman)

## Pictures and Photography

Avoision: Vintage Bazaar, Pilsen, Chicago Street Art Show @ Chicago Urban Art Society

Bradley Garrett: Las Vegas Undercity

Locohama: Tweet-up at a Maid Cafe in Akihabara

Alex Papadimoulis: Labview Spaghetti

Telefunker: I-Beton B: Abandoned concrete factory in Belgium, Zeche L: Abandoned coal mine somewhere in Germany

Urbex Israel: Tel Aviv University Tunnels