Tuesday, May 31, 2016

Monday, May 30, 2016

Kershaw's Strikeout:Walk Dominance

Clayton Kershaw has been especially dominant so far this year and last night reached 100 strikeouts with only 5 walks, the fewest walks with 100 strikeouts in the modern (i.e., post-1900) era. Wow!

Kershaw's career has been historically dominant so far.

Note: The use of 'modern' is a hedge, simply because Major League Baseball record-keeping was much sketchier before 1900. It's not that we know another player did this, but basically that people don't know and are being cautious about the phrasing.

Saturday, May 28, 2016

Top Spelling Queries by U.S. State

This map of the top spelling queries by U.S. state is great. Notice the fixed point in the northeast! (Also notice the entry for Alaska.)

Note: The article title calls them spelling "mistakes", but it appears instead to be spelling queries.

Pedestrian Standoffs and Symmetry Breaking

My latest post for the Improbable Research blog concerns pedestrian standoffs and symmetry breaking.

Thursday, May 26, 2016

Meanwhile, in Wales...

I am highly amused by this headline, which I have reproduced for the screenshot below.


And then maybe we'll get a sequel to the movie Black Sheep.

Note: One can also find comments like the following online: "The 'psychotic sheep' story is fake. It's the UK media at its very worst. It is dishonest reporting based on distortion of one stupid farmer's delusional ideas. It never happened." Nevertheless, I find the headline to be very amusing.

Wednesday, May 25, 2016

"Scattering of Waves by Impurities in Precompressed Granular Chains"

You may have heard of the Ramsaur–Townsend resonance from scattering problems. The simplest version of it (by examing a particle in a square well) is one of the canonical textbook problems in quantum mechanics.

This is one of the important effects illustrating the need for a notion of wave mechanics.

It turns out that one can also get an RT resonance in a macroscopic, classical system.

The discovery of this classical RT effect (in granular crystals) is the subject of a paper by my collaborators and me, out in final form in Physical Review E today. Here are the details of the article.


Title: "Scattering of Waves by Impurities in Precompressed Granular Chains"

Authors: Alejandro J. Martínez, Hiromi Yasuda, Eunho Kim, P. G. Kevrekidis, Mason A. Porter, and Jinkyu Yang

Abstract: We study scattering of waves by impurities in strongly precompressed granular chains. We explore the linear scattering of plane waves and identify a closed-form expression for the reflection and transmission coefficients for the scattering of the waves from both a single impurity and a double impurity. For single-impurity chains, we show that, within the transmission band of the host granular chain, high-frequency waves are strongly attenuated (such that the transmission coefficient vanishes as the wavenumber k → ±π), whereas low-frequency waves are well-transmitted through the impurity. For double-impurity chains, we identify a resonance—enabling full transmission at a particular frequency—in a manner that is analogous to the Ramsauer–Townsend (RT) resonance from quantum physics. We also demonstrate that one can tune the frequency of the RT resonance to any value in the pass band of the host chain. We corroborate our theoretical predictions both numerically and experimentally, and we directly observe almost complete transmission for frequencies close to the RT resonance frequency. Finally, we show how this RT resonance can lead to the existence of reflectionless modes in granular chains (including disordered ones) with multiple double impurities.

Tuesday, May 24, 2016

Infographics on Shakespearian Deaths

I love these Tufte-ian infographics on deaths in Shakespearean tragedies, especially the one for the bloodbath Titus Andronicus.

As I mentioned previously on my blog, Shakespearean deaths have also been tabulated in pie-chart form.

Sunday, May 22, 2016

"Eye of the Tiger": Homework Marking Edition

The first song that played today as I started marking homework assignments was "Eye of the Tiger". I can already imagine the music video!

Sadly, I wasn't done with my marking by the end of the song, as surely would have been the case were this actually a movie montage. Damn.

Saturday, May 21, 2016

Inference Club

The Mathematical Institute at University of Oxford now has an "Inference Club".

Which leads me to... First Rule of Inference Club: you ought to be able to figure it out.

Friday, May 20, 2016

R-Rated Version of Real Analysis

The new SMBC shows you what you learn when you take the R-rated version of real analysis.

Wednesday, May 18, 2016

A Spectacular Rejection Letter for Einstein (but Unfortunately it's Fake)

Albert Einstein once received this spectacular rejection letter. Wow!

(Tip of the cap to Nelson Fernández.)

Update: Thanks to Sam Cohen for suggesting that I look up whether this letter is fake. It is.

Tuesday, May 17, 2016

I Wonder Who's Going to Play ⊦ in the "Tetris" Movie?

Yes, that's right: in a puzzling development, there's going to be a movie based on the game "Tetris". I wonder who will be cast to play ⊦? Also, WTF?

Sunday, May 15, 2016

What Happens in Lake Como Stays in Lake Como

Today I'm flying to Italy to participate in the second Lake Como School on Complex Networks. I'll be giving a tutorial on mesoscale structures in networks.

Saturday, May 14, 2016

An Awesome 19th-Century Visualization of a Railroad Network

This 19th-century visualization of the New York and Erie Railroad is spectacular. Visually, it accentuates a possible core–periphery structure. (One expects railroad networks to have such a structure, although visualizations on their own can be very misleading, so one would need to check this to be sure.)

(Tip of the cap to Edward Tufte.)

Update: Here is an embedded version of the tweet so that you can see the picture without clicking on the link above.

Friday, May 13, 2016

The Learning Curve in 'R'

Here it is. We need a version of this cartoon that compares 'R' with Matlab, Python, etc. (Also, it's fun to make fun of 'R'.)

(Tip of the cap to Felice Jacka.)

Thursday, May 12, 2016

A Colorful Bird

Here is a gorgeous, very colorful bird.

(Tip of the cap to IFLS.)

Wednesday, May 11, 2016

Civilization VI!!!

Oh, Hell yes!!!!

Just. One. More. Turn.

(Tip of the cap to Louis Wang.)

Tales from the ArXiv: "With Inertia and Frustration"

The title of a new paper on the arXiv this morning is "Bifurcations and singularities for coupled oscillators with inertia and frustration".

I could add the phrase "with inertia and frustration" to the end of the title of just about any of my papers, and it would be accurate.

(OK, both terms have specific technical meaning in this case, but work with me.)

Monday, May 09, 2016

The 10 Unlikeliest Home Runs Ever Hit

In celebration of Bartolo Colón's epic first career homerun (which makes him the older Major League Baseball player ever to his his first career home run), David Schoenfield has compiled a list of the 10 unlikeliest home runs in Baseball history. Awesome! Colón's home-run trot is also awesome.

There are some beauties on this list of unlikely home runs (except the one by Ozzie Smith... that one should be banned).

Colón is also the "last Expo standing" (i.e., the last active Major League player to have played for the Expos). What am amazing career!

RIP Tom Apostol (1923–2016)

Caltech lost a legend today: Tom Apostol has died.

Here I quote from Kevin Hickerson's Facebook post (whence I got the news): Our department lost a great one today. Tom M. Apostol, emeritus professor of Mathematics, is well known among math and science students the world over, including 100% of all Caltech alums, for his mathematically rigorous and technically unmatched textbooks on Calculus, affectionately known as "Tommy I" and "Tommy II" (1923-2016) RIP

I never did take a class with Apostol, as he retired from teaching classes just before I got to Tech. I skipped Math 1, so I only ended up using Tommy II as a textbook.

Update (5/10/16): Caltech has posted an obituary.

Saturday, May 07, 2016

Flying with Differential Equations

Apparently, solving differential equations on a flight now can raise suspicion. Grrrrr....

In an attempt to try to turn some lemons into lemonade (and to be snarky), here is a tweet I wrote for DynamicalSystemsSIAM.



(Tip of the cap to Physics Girl for the news story.)

Friday, May 06, 2016

What Researchers Study

And, on this occasion, the bioengineers finally get to appear in the punchline. (I can already imagine their maniacal laughter.)

PLOS ONE and Donald Trump

Apparently, this is a match made in Heaven.

Wow. Just wow.

(Tip of the cap to Ernie Barreto.)

Update (5/7/16): Ashley Landrum has re-analyzed the data from the paper and come to very different conclusions (and torn the paper apart). (Tip of the cap to Sharon Lubkin.)

Tuesday, May 03, 2016

Monday, May 02, 2016

Message in a Bottle

Sending an SOS to the world pretty much is replying-all.

(And one could also bring up passive tracers.)

Sunday, May 01, 2016

2017 Research Parasite Award

There is now a call for applications for the 2017 Research Parasite Award. I approve!

(Tip of the cap to Alex Vespignani.)