Thursday, March 23, 2017

"The Multilayer Nature of Ecological Networks"

Our perspective paper on multilayer networks in ecology is out in final form today! Here are the details.

Title: The Multilayer Nature of Ecological Networks

Authors: Shai Pilosof, Mason A. Porter, Mercedes Pascual, and Sonia Kéfi

Abstract: Although networks provide a powerful approach to study a large variety of ecological systems, their formulation does not typically account for multiple interaction types, interactions that vary in space and time, and interconnected systems such as networks of networks. The emergent field of ‘multilayer networks’ provides a natural framework for extending analyses of ecological systems to include such multiple layers of complexity, as it specifically allows one to differentiate and model 'intralayer' and 'interlayer' connectivity. The framework provides a set of concepts and tools that can be adapted and applied to ecology, facilitating research on high-dimensional, heterogeneous systems in nature. Here, we formally define ecological multilayer networks based on a review of previous, related approaches; illustrate their application and potential with analyses of existing data; and discuss limitations, challenges, and future applications. The integration of multilayer network theory into ecology offers largely untapped potential to investigate ecological complexity and provide new theoretical and empirical insights into the architecture and dynamics of ecological systems.

Wednesday, March 22, 2017

An Evans Function: A Wronskian on Crack

Definition: An Evans function is a Wronskian on crack.

I'm pretty sure that this is the official definition that you'll find in many mathematics books.

In case you're interested in these objects, see Todd Kapitula's primer. And here is a new article by Chris Jones that reminded me of the above definition.

Actually, I'm pretty sure I once heard someone — maybe even Chris? — joking call an Evans function "a Wronskian on steroids" during a seminar. I remember thinking that 'on steroids' probably wasn't doing justice to the function.

An "Unsung" Collection of Songs

I love how words evolve: a collection of things that literally are sung are now "unsung" masterpieces, and it makes perfect sense.

Oh, what the bards of yore have wrought.

Tuesday, March 21, 2017

Yves Meyer Wins 2017 Abel Prize!

Yves Meyer has won the 2017 Abel Prize for his work on the theory of wavelets. Here is an article in Nature about it.

I am puzzled as to why Ingrid Daubechies didn't share this prize.

Update: Terry Tao has written a short blog post about the prize. Among other things (and I hadn't caught this), note the following text from Tao: Daubechies also made extremely important contributions to the theory of wavelets, but my understanding is that due to a conflict of interest arising from Daubechies’ presidency of the International Mathematical Union (which nominates members of the Abel prize committee) from 2011 to 2014, she was not eligible for the prize this year, and so I do not think this prize should be necessarily construed as a judgement on the relative contributions of Meyer and Daubechies to this field.

Wednesday, March 15, 2017

Oxford Comma: The Revenge

And, sometimes, the lack of an Oxford comma might determine the outcome of a court case.

Also see previous blog entries of mine, such as this one, this one, and this one.

Vindication is mine!

(Tip of the cap to Jaideep Taggart Singh.)

Update: Aaron Clements pointed me to this Washington Post article.

The Tensor: A Reboot of The Matrix

I assume that the reboot of The Matrix will be called "The Tensor".

Also see my Facebook post about this for witty repartee, other suggested names, and possible prequels (e.g., "The Vector").

(Tip of the cap to Sammy Kline for the information about the reboot.)

We Studied Network Structure, and Then the Murders Began

This article on The Daily Dot suggests adding the phrase "and then the murders began" to the first sentence of the book that one is reading. This can change the tone of the book in very amusing ways.

As a twist on this, I decided to look at the first sentence of the preface of one of my books. This yields the following sentence: "Traditionally, much of the study of networks has focused on structural features, and then the murders began."

Unfortunately, the tense of the sentence hurts things, so I am going to change one letter ("s" to "d" in the word "has") to produce the following sentence: "Traditionally, much of the study of networks had focused on structural features, and then the murders began."

Much better! (And highly amusing.)

(Tip of the cap to Keith Fraser.)

"Best-Tasting Colors"

I don't completely agree with the new XKCD, but there is some truth here.

I would move "cherry" way over to the right.

I did recently have an experience with eating a pink Starburst and expecting strawberry but getting watermelon instead. It was unpleasant.

Even more unpleasant are past experiences of eating red with the hope that it's cherry but then getting cinnamon instead.


Tuesday, March 14, 2017

Happy Pi Day!

Today is, of course, Pi Day. And I love how the Colorado Rockies celebrated it today!

(Tip of the cap to Jeremy Stell.)

Update (3/19/17): I forgot to mention that I found out a few days ago that there was some Photoshopping in the above picture. It's still very cool, though not quite as cool as before.

Sonyalytic Acquired by Spotify

OK, but what does that have to do with me?

Well, Martin Gould is CEO of Sonalytic, which was just acquired by Spotify! Very well done!

Saturday, March 11, 2017

"Artistic Expressions of Math Over Seven Centuries"

My favorite picture in this article (in Hyperallergic) by Allison Meier is "Garden of Mathematical Sciences". So sweet!

This article, which has lots of great pictures of mathematical art, is a review of the exhibit Picturing Math at the Metropolitan Museum of Art in New York City.

(Tip of the cap to James Tanton.)

Thursday, March 09, 2017

What Happens in Houston Stays in Houston

Today I am flying out to Houston to give the mathematics colloquium tomorrow at University of Houston, Downtown.