Tuesday, August 14, 2018
I am looking forward to geeking out!
(I am also looking forward to getting out of this crowded, shitty airport. LAX is awful.)
Monday, August 13, 2018
Earlier today, I was looking for 'balance' in "Social Network Analysis" by Wasserman & Faust, but instead I found the 'beast'.— Mason Porter (@masonporter) August 13, 2018
(I suppose that social network analysis is sometimes a Wassermanian–Faustian bargain.) pic.twitter.com/cm4jZiupeW
Friday, August 10, 2018
Title: Network Analysis of Particles and Grains
Authors: Lia Papadopoulos, Mason A. Porter, Karen E. Daniels, and Danielle S. Bassett
Abstract: The arrangements of particles and forces in granular materials have a complex organization on multiple spatial scales that range from local structures to mesoscale and system-wide ones. This multiscale organization can affect how a material responds or reconfigures when exposed to external perturbations or loading. The theoretical study of particle-level, force-chain, domain and bulk properties requires the development and application of appropriate physical, mathematical, statistical and computational frameworks. Traditionally, granular materials have been investigated using particulate or continuum models, each of which tends to be implicitly agnostic to multiscale organization. Recently, tools from network science have emerged as powerful approaches for probing and characterizing heterogeneous architectures across different scales in complex systems, and a diverse set of methods have yielded fascinating insights into granular materials. In this article, we review work on network-based approaches to studying granular matter and explore the potential of such frameworks to provide a useful description of these systems and to enhance understanding of their underlying physics. We also outline a few open questions and highlight particularly promising future directions in the analysis and design of granular matter and other kinds of material networks.
Thursday, August 09, 2018
Monday, August 06, 2018
Tired of expensive diversity initiatives that haven’t really changed much? So are we 😴. We want to give you 💰 to work on projects based on evidence. Meet new people, change the game. Join us on Sept 21 + 22 @turinginst: https://t.co/gOH4KvRQM7 #womeninSTEM x @STEMGamechange pic.twitter.com/PPgDvIqqy9— Dr Jess Wade 👩🏻🔬 (@jesswade) July 25, 2018
(P.S. Jess Wade has been doing amazing things in her prolific writing of Wikipedia entries.)
Saturday, August 04, 2018
Thursday, August 02, 2018
Previously, we wrote an obituary of Zabusky for DSWeb.
Wednesday, August 01, 2018
You can also read short prize citations for the four Fields Medalists and the Nevanlinna Prize (in theoretical computer science).
Tuesday, July 31, 2018
Title: Topological Data Analysis of Continuum Percolation with Disks
Authors: Leo Speidel, Heather A. Harrington, S. Jonathan Chapman, and Mason A. Porter
Abstract: We study continuum percolation with disks, a variant of continuum percolation in two-dimensional Euclidean space, by applying tools from topological data analysis. We interpret each realization of continuum percolation with disks as a topological subspace of [0,1]^2 and investigate its topological features across many realizations. Specifically, we apply persistent homology to investigate topological changes as we vary the number and radius of disks, and we observe evidence that the longest persisting invariant is born at or near the percolation transition.
And to give a story, or at least the hint of the interesting relationship that I sometimes have with typesetters and editors, here is a note that I received from them while we were working on the galley proofs.
Update (8/05/18): A nice way of phrasing things is that we're in a nonassociative situation, and hyphens are a great tool to indicate exactly (and tersely) where the parentheses should be to group terms in a way that renders their meaning unambiguous. (And, naturally, if somebody makes a change in my text that I don't like, my immediate desire is to change it back.)
Monday, July 30, 2018
great meme pic.twitter.com/d5AW6WliTy— Lex Flagel (@flagelbagel) July 29, 2018
(Tip of the cap to Michael Stumpf.)
Also, remember the mantra: FIPO (= "Fuck it. PLOS One.")
Sunday, July 29, 2018
(However, I do wish that the author had used the subjunctive in the 'what if' question.)
"Blueberry Earth" (new paper) by Anders Sandberg: https://t.co/hn1T10qErC— DynamicalSystemsSIAM (@DynamicsSIAM) July 30, 2018
Abstract: 'This paper explores the physics of the what-if question "what if the entire Earth was instantaneously replaced with an equal volume of closely packed, but uncompressed blueberries?" ... '
Update: Here is the first paragraph of the Summary: So, to sum up, to a person standing on the surface of the Earth when it turns into blueberries, the first effect would be a drastic reduction of gravity. Standing on the blueberries might be possible in theory, except that almost immediately they begin to compress rapidly and air starts erupting everywhere. The effect is basically the worst earthquake ever, and it keeps on going until everything has fallen 715 km. While this is going on everything heats up drastically until the entire environment is boiling jam and steam. The end result is a world that has a steam atmosphere covering an ocean of jam on top of warm blueberry granita.
Saturday, July 28, 2018
My biggest weakness pic.twitter.com/WvIeVPqoTl— Toby Hendy (@TobyHendy) July 28, 2018
(1) One of the main purposes of taking complex analysis is learning how to properly write Greek letters.
(2) I specifically practiced how to draw \xi when I took complex analysis.
(Tip of the cap to Dave Richeson.)
"Where did the authors smurf up this idea?"
"This figure is smurfed."
"The authors might want to consider smurfing the abstract a little bit more."
Update: I know; I know: this isn't very smurfy of me.
Update 2: "A total smurf job."
Tuesday, July 24, 2018
Here is a quote from the abstract: In the limit of low Mason number, the dynamical system admits a periodic solution in which the magnetic moment of the swimmer tends to align with the magnetic field. In the limit of large Mason number, the magnetic moment tends to align with the average magnetic field, which is parallel to the axis of rotation.
I operate in the limit of low Mason number, and I claim that this limit is singular.
Monday, July 23, 2018
Moreover: Hell yes!
This is a major issue for interdisciplinary students and postdocs (and more senior scholars), and this is a very helpful paper for them to read as they navigate these waters. I also really like the fact that Ray included two different versions of a 'Results' section in his opinion article.
Title: Quasiperiodic Granular Chains and Hofstadter Butterflies
Authors: Alejandro J. Martínez, Mason A. Porter, and Panayotis G. Kevrekidis
Abstract: We study quasiperiodicity-induced localization of waves in strongly precompressed granular chains. We propose three different set-ups, inspired by the Aubry–André (AA) model, of quasiperiodic chains; and we use these models to compare the effects of on-site and off-site quasiperiodicity in nonlinear lattices. When there is purely on-site quasiperiodicity, which we implement in two different ways, we show for a chain of spherical particles that there is a localization transition (as in the original AA model). However, we observe no localization transition in a chain of cylindrical particles in which we incorporate quasiperiodicity in the distribution of contact angles between adjacent cylinders by making the angle periodicity incommensurate with that of the chain. For each of our three models, we compute the Hofstadter spectrum and the associated Minkowski–Bouligand fractal dimension, and we demonstrate that the fractal dimension decreases as one approaches the localization transition (when it exists). We also show, using the chain of cylinders as an example, how to recover the Hofstadter spectrum from the system dynamics. Finally, in a suite of numerical computations, we demonstrate localization and also that there exist regimes of ballistic, superdiffusive, diffusive and subdiffusive transport. Our models provide a flexible set of systems to study quasiperiodicity-induced analogues of Anderson phenomena in granular chains that one can tune controllably from weakly to strongly nonlinear regimes.
This article is part of the theme issue ‘Nonlinear energy transfer in dynamical and acoustical systems’.
Sunday, July 22, 2018
(Also, I am highly amused!)
Money quote from the programming language's GitHub page:
"Rockstar is a dynamically typed Turing-complete programming language.
Rockstar is designed for creating computer programs that are also song lyrics, and is heavily influenced by the lyrical conventions of 1980s hard rock and power ballads."
Update (7/23/18): I wrote a blurb about Rockstar for the Improbable Research blog.
Saturday, July 21, 2018
I love this.— Jim Bliss (@JimBliss23) July 21, 2018
When the Far Side came out in 1982, paleontologists realised they'd never actually named that part of a stegosaurus and began using the term informally. And now, 36 years later, if you type "Thagomizer" into a search engine... pic.twitter.com/pMDYoOrT8d
(Tip of the cap to C E Watkins.)
Friday, July 20, 2018
“Mason’s knowledge was as faded as the book from the British sun.”— Mason Porter (@masonporter) July 20, 2018
Proof of existence of sunlight in England. :) pic.twitter.com/d7z7YbgLAy
Thursday, July 19, 2018
Wednesday, July 18, 2018
Quoting from the abstract: "The model is highly versatile, as the motion of the walkers can be fed on topological properties of the nodes..."
Comment: But don't feed them after midnight.
With Corey Seager out for the year, having Machado to play shortstop the rest of the year is most excellent indeed!
Tuesday, July 17, 2018
Monday, July 16, 2018
Friday, July 13, 2018
Wednesday, July 11, 2018
On some website pop-up menus, there are so many possible titles that it's really hard to choose the most appropriate one to use.— Mason Porter (@masonporter) July 11, 2018
(Click to see the full list. Some selections are cut off.) pic.twitter.com/mRgnGMMxkd
Now we just need real-life Sinai and stadium billiards (and, of course, a mushroom billiard, to make Lyonia happy).
Unveiling the elliptical pool table designed by @AlexBellos captured local imagination: https://t.co/BlSu2PQ95m , https://t.co/bPVtkHF6Bh , https://t.co/MPAdoNv8pU . 1st in North America, 3rd in the world. Planning formal event at @WaterlooMath in the fall.— Stephen M. Watt (@Stephen_Watt) July 11, 2018
(Tip of the cap to Alex Bellos.)
Update: The table pictured in the article appears to be a circle, rather than a more general ellipse.
I have never laughed out loud reading a journal article, until I saw this little gem from Lakens, Scheel, and Isager (2018). Talk about total transparency!https://t.co/4eAsdvFbMI pic.twitter.com/OsVUTYf71e— Stacy T. Shaw 🇭🇷 (@StacyTShaw) July 11, 2018
Tuesday, July 10, 2018
Ukrainian photographer Vyacheslav Mishchenko catches these unbelievably stunning up-close photographs of snails pic.twitter.com/Lhgj2zcx6S— Life on Earth 🌴 (@planetepics) July 10, 2018
(Tip of the cap to Invisible Scientist.)
Thursday, July 05, 2018
Interested in #MASON for agent-based modeling? Check out our new paper: The MASON Simulation Toolkit: Past, Present, and Future. More details @ https://t.co/II9TFkQ7SU The link also points you to a lot of new demo models for GIS & ABM pic.twitter.com/8OnbC5ckud— Andrew Crooks (@AndyCrooks) July 4, 2018
(Tip of the cap to Sang Hoon Lee.)
Tuesday, July 03, 2018
And now, on this occasion, even the band itself accidentally tagged me in their Facebook post instead of themselves!
Rock on! ("Folk on?")
One of these years, I seriously need to crash one of their shows with a short mathematics lecture.
Monday, July 02, 2018
Sunday, July 01, 2018
Thursday, June 28, 2018
Here is a picture with him at Dragon*Con in 2003. He complimented me on the shirt I was wearing, and rolled his eyes to signal to me (while I was waiting patiently at the front of the line) that the person in front of me in line for his autograph (who gave him tons and tons of things to sign) was an idiot. For me, he signed a well-read copy of the 35-year retrospective of his work, and he agreed to be in the picture below. Unlike recent Dragon*Cons, Ellison's autograph was free. He seemed to appreciate the fact that I had obviously read the book that I asked him to sign.
Update: Here is an obituary from The Nerdist.
Tuesday, June 26, 2018
Parasitic crustacean, Dendrogaster sp. found on the seastar, Mediaster brachiatus. Collected at depth of 300m, Kumanonada-sea, Japan. pic.twitter.com/uy2J3FD2dk— M (@manpokenautilus) June 25, 2018
Other examples of living networks are fungal networks.
(Tip of the cap to Jessica Rosenkrantz.)
Monday, June 25, 2018
(Tip of the cap to Peter Rothman.)
Sunday, June 24, 2018
I strongly recommend looking through Tiling Bot's feed.
Saturday, June 23, 2018
I'll also be participating and speaking at Howison-fest, a workshop in honor of Sam Howison's 60th birthday.
Thursday, June 21, 2018
Remember: "FUs are biologically well defined".
This screenshot is from this new paper.
(Tip of the cap to Alex Vespignani.)
Wednesday, June 20, 2018
A surface obtained by gluing six heptagons. Universal cover in the Poincaré model (the same character shown = the same point of the surface). Weapons to show that this is not orientable (it has Euler characteristic -1). Constructed by DivisionByZero [ https://t.co/zgD3J7pG4f ] pic.twitter.com/J1MzJKCkYl— Zeno Rogue (@ZenoRogue) June 20, 2018
The image appears to bulge out, though it consists of squares aligned vertically and horizontally. pic.twitter.com/uwb0HJPyiw— Akiyoshi Kitaoka (@AkiyoshiKitaoka) June 20, 2018
(Tip of the cap to Ben Orlin.)
Tuesday, June 19, 2018
Quoting the article's lead: Just as an earthquake’s seismic waves reveal properties of Earth’s interior, elastic surface waves on an apple can tell us about what’s going on inside the fruit.
This research may be a contender for an Ig Nobel prize.
Update: Apple seismology was discussed originally in a 1973 mathematical modeling paper by J.R. Cooke and Richard Rand. (This paper is cited in the Physics Today article above.)
Quoting from the article to which I linked:
On Monday, the Washington Nationals rookie crushed a tiebreaking, pinch-hit, two-run homer against the New York Yankees in the continuation of a game that started May 15 — five days before his big league debut.
According to the Elias Sports Bureau, Soto's blast will not be considered his first major league homer, but it will be counted as a home run hit on May 15.
Saturday, June 16, 2018
Title: Female Drosophila melanogaster Respond to Song-Amplitude Modulations
Authors: Birgit Brüggemeier, Mason A. Porter, Jim O. Vigoreaux,and Stephen F. Goodwin
Abstract: Males in numerous animal species use mating songs to attract females and intimidate competitors. We demonstrate that modulations in song amplitude are behaviourally relevant in the fruit fly Drosophila. We show that Drosophila melanogaster females prefer amplitude modulations that are typical of melanogaster song over other modulations, which suggests that amplitude modulations are processed auditorily by D. melanogaster. Our work demonstrates that receivers can decode messages in amplitude modulations, complementing the recent finding that male flies actively control song amplitude. To describe amplitude modulations, we propose the concept of song amplitude structure (SAS) and discuss similarities and differences to amplitude modulation with distance (AMD).
Thursday, June 14, 2018
He passed Ichiro in the game that ended a few hours ago.
Saturday, June 09, 2018
Sunday, June 03, 2018
LaTeX is so much better when you have emoji. pic.twitter.com/SYxgUXpWYN— Mike Bostock (@mbostock) June 2, 2018
(Tip of the cap to Karen Daniels.)
I'm happy to announce the triumphant return of The Power Law Shop!https://t.co/1sgZacqhhv— Mason Porter (@masonporter) June 3, 2018
Just in time for #netsci2018 (@netsci2018).
We're trying to fill a universal and critical need for scale-free swag.
Saturday, June 02, 2018
Well, I just didn’t realise that Jack and Jill had so many mishaps as well as falling down the hill. Here are some, as recounted in this little 1806 chap book, just 212 years ago https://t.co/SnLDtBTCia pic.twitter.com/mBkro0bvmn— Journal of Art in Society (@artinsociety) June 3, 2018
'Mathematics is an experimental science, and definitions do not come first, but later on.' -- Oliver Heaviside— Analysis Fact (@AnalysisFact) June 1, 2018
(Tip of the cap to Steve Strogatz.)
Friday, June 01, 2018
Thursday, May 31, 2018
A part that some of you may find interesting is the pedagogical discussion at the beginning of Section 5, which starts: "Historically, there are five ways that spherical harmonics can be derived."
The one that is easiest (by far) for me to understand is the oldest method, which is by solving the differential equation. But I am mathematically inclined, and people with more physical intuition may prefer other methods.
(People who are more comfortable than I am with Lie manipulations may also prefer other approaches.)
Anyway, I appreciate the discussion in this paper.
Sunday, May 27, 2018
Title: Can Multilayer Networks Advance Animal Behavior Research?
Authors: Matthew J. Silk, Kelly R. Finn, Mason A. Porter, and Noa Pinter-Wollman
Abstract: Interactions among individual animals — and between these individuals and their environment — yield complex, multifaceted systems. The development of multilayer network analysis offers a promising new approach for studying animal social behavior and its relation to eco-evolutionary dynamics.
Thursday, May 24, 2018
The Rays are doing this again in their upcoming series against the Orioles.
I think there is a lot of traction for more of this, though it will depend on a team's rotation (e.g., if you have one like the Astros, this is probably not as helpful as for the Rays), player, player egos, and so on.
Tuesday, May 22, 2018
Thursday, May 17, 2018
(Tip of the cap to Brian Cox.)
Tuesday, May 15, 2018
'Working Paper' in Collaboration with International Monetary Fund: "Evolution of the Global Financial Network and Contagion: A New Approach"
Title: Evolution of the Global Financial Network and Contagion: A New Approach
Authors: Yevgeniya Korniyenko, Manasa Patnam, Rita Maria del Rio-Chanon, and Mason A. Porter
Abstract: This paper studies the interconnectedness of the global financial system and its susceptibility to shocks. A novel multilayer network framework is applied to link debt and equity exposures across countries. Use of this approach—that examines simultaneously multiple channels of transmission and their important higher order effects—shows that ignoring the heterogeneity of financial exposures, and simply aggregating all claims, as often done in other studies, can underestimate the extent and effects of financial contagion.The structure of the global financial network has changed since the global financial crisis, impacted by European bank’s deleveraging and higher corporate debt issuance. Still, we find that the structure of the system and contagion remain similar in that network is highly susceptible to shocks from central countries and those with large financial systems (e.g., the USA and the UK). While, individual European countries (excluding the UK) have relatively low impact on shock propagation, the network is highly susceptible to the shocks from the entire euro area. Another important development is the rising role of the Asian countries and the noticeable increase in network susceptibility to shocks from China and Hong Kong SAR economies.
Mathematics and physics get the familiar, cheesy writing-in-the-mirror treatment in some of these.
(Tip of the cap to Justin Howell.)
My first publication (except items in @Caltech's newspaper) was not mathematical or scientific in any way. It was a Dungeons & Dragons character!— Mason Porter (@masonporter) May 15, 2018
I won a contest to design the thief on a cover of Polyhedron.
(For it, I corresponded with editor @erikmona.) #myfirstpublication pic.twitter.com/tTfFHVFdPk
Saturday, May 12, 2018
Here is the context: Physics Today has agreed to publish an obituary for Norman Zabusky, so I needed to find some information that they require to be part of it. This led me to Norman's PhD thesis, which I found online. It briefly mentions something called Lommel polynomials, with which I wasn't familiar. The definition in a thesis appendix was terse — it's not exactly an important part of the thesis — so I looked at Wikipedia, and I kept seeing links to special functions that weren't familiar to me, and I have followed a couple of them. Anger functions are one family.
These various special functions are closely related to Bessel functions.
Thursday, May 10, 2018
(Tip of the cap to Jane Shevtsov.)
Wednesday, May 09, 2018
Maybe a nice piece of art to go with somebody starting to write the initial draft of an academic paper would be a picture of a scientist quite literally taking an initial stab through a pile or papers or perhaps through a laptop.
(If anybody has a favored website for etymology and similar matters, please let me know. I was hoping my global search would turn up a good answer on one of those pages.)
And, by all means, somebody should take the first stab at answering my query.
Here is the video of my tutorial on paper-writing in applied mathematics: https://t.co/uAbUatOpnS— Mason Porter (@masonporter) May 9, 2018
For reasons unbenownst to me, YouTube decided to classify it as a "comedy".
Maybe that's a feature, rather than a bug?
You can also download the slides.
I hope that people find it helpful!
Tuesday, May 08, 2018
Title: Configuring Random Graph Models with Fixed Degree Sequences
Authors: Bailey K. Fosdick, Daniel B. Larremore, Joel Nishimura, and Johan Ugander
In 2014, Aaron Clauset, David Kempe, and I (with help from Dan Larremore) organized a Mathematics Research Community in Network Science.
In addition to creating a network of network scientists from diverse backgrounds, some work was started there, and today the published version of what is in my opinion an extremely important paper has come out in final form in SIAM Review's 'Research Spotlights' section. I am, of course, talking about the aforementioned paper.
I'm very happy indeed for such excellent work to arise from this.
Congratulations to authors Bailey Fosdick, Daniel Larremore, Joel Nishimura, and Johan Ugander for creating this awesome paper!
I am posting this with an absolutely lovely Seussian picture from an arXiv version of the paper. This picture doesn't appear to have made the cut for the published piece. In addition to its wit and whimsy, a really great thing about the picture and its accompanying verse is that it also encodes the main message of the paper.
Note: I am on the editorial board of the Research Spotlights section of SIAM Review, but I had nothing whatsoever to do with the handling of this paper.
Friday, May 04, 2018
Thursday, May 03, 2018
Tuesday, May 01, 2018
Sunday, April 29, 2018
My favorite is the use of " \; ", which would allow the cheating student being modeled by the picture to ensure legible symbol spacing when writing exam solutions.
Saturday, April 28, 2018
Hurray! Science vindicates my longstanding practice, learned at age 12, of using TWO SPACES after periods in text. NOT ONE SPACE. Text is easier to read that way. Of course, on twitter, I use one space, given 280 characters. https://t.co/4xI6sVbF88 Will arm-wrestle @Neuro_Skeptic pic.twitter.com/XpEr4KFR4x— Nicholas A. Christakis (@NAChristakis) April 28, 2018
Wednesday, April 25, 2018
Tuesday, April 24, 2018
Monday, April 23, 2018
Title: Nanoptera in a Period-2 Toda Chain
Authors: Christopher J. Lustri and Mason A. Porter
Abstract: We study asymptotic solutions to a singularly perturbed, period-2 Toda lattice and use exponential asymptotics to examine "nanoptera," which are nonlocal solitary waves with constant-amplitude, exponentially small wave trains. With this approach, we isolate the exponentially small, constant-amplitude waves, and we elucidate the dynamics of these waves in terms of the Stokes phenomenon. We fi nd a simple asymptotic expression for these waves, and we study con figurations in which these waves vanish, producing localized solitary-wave solutions. In the limit of small mass ratio between the two types of particles in the lattice, we derive a simple antiresonance condition for the manifestation of such solutions.
Thursday, April 19, 2018
Tuesday, April 17, 2018
They’re not bad. I wouldn’t call them gorgeous, though.
Sunday, April 15, 2018
Look at the back of this bag, look carefully at the bottom left corner … 🤩 pic.twitter.com/P5SusNDYtY— Nalini Joshi (@monsoon0) April 16, 2018
Monday, April 09, 2018
As part of their correspondence today, they also let the first author (my former doctoral student) know about the option of a young-scientist, first-author spotlight. They wrote the following (which you can also find on their website):
Congratulations on acceptance of your article in Biology Open. To help early-career researchers promote themselves alongside their papers, we have launched a series of interviews with the first authors of a selection of papers published in BiO. If you would like to be included in this interview series, please tell us more about yourself by answering the questions below. You can answer all or just some of the questions, and you may also suggest additional questions and provide your answers to them if you wish.
How interesting! I have never seen a journal do this before. What a great idea! We really need to do something like this in the mathematics and physics communities.
Here are their suggested questions:
What is your scientific background and the general focus of your lab?
How would you explain the main findings of your paper to non-scientific family and friends?
What are the potential implications of these results for your field of research?
What has surprised you the most while conducting your research?
What, in your opinion, are some of the greatest achievements in your field and how has this influenced your research?
What changes do you think could improve the professional lives of early career scientists?
What's next for you?
They then added the following:
So that we can create a short biography to accompany your interview, please ensure that you include your job title, the name of the Principal Investigator of your lab, your contact address and a one-line synopsis of your research interests. Include your Twitter handle, if you have one, so we can tag you in any related tweets.
They also asked for a picture of the first author and "a particularly striking, interesting or unusual image" from their research (along with a caption describing it).
Thursday, April 05, 2018
Title: On the Wonderfulness of Noether's Theorems, 100 Years Later, and Routh Reduction
Author: Raphaël Leone
Abstract: This paper is written in honour of the centenary of Emmy Amalie Noether's famous article entitled Invariante Variationsprobleme. It firstly aims to give an exposition of what we believe to be the most significant and elegant issues regarding her theorems, through the lens of classical mechanics. Despite the limitation to this field, we try to illustrate the key ideas of her work in a rather complete and pedagogical manner which, we hope, presents some original aspects. The notion of symmetry coming naturally with the idea of simplification, the last part is devoted to the interplay between Noether point symmetries and the reduction procedure introduced by Edward John Routh in 1877.
Sunday, April 01, 2018
While navigating the menus, I managed to get eaten by a grue.
There are errors in some of the D & D categorizations.
The first one that I want to mention is ThinkGeek's catalog. (Tip of the cap to Jennifer Ouellette.)
As usual, there are some special papers on the arXiv, including this one and this one.
Here is another joke arXiv paper. (Tip of the cap to Chad Topaz.)
Here is a roundup of Google's jokes, including the ability to play "Where's Waldo?" on Google Maps.
Saturday, March 31, 2018
Friday, March 30, 2018
By the way, my d30 (where I rolled again for any results from 27–30) rolled 20 three times during this process, and its only roll below 18 was a single 14, with all but those two rolls in the 20s (including a few of at least 27). Clearly, this is a damage die.
Also, can we get a chart like this for cover letters and grant proposals, please?
P.S. A social media addiction should be contrasted with an antisocial media addiction.
(Tip of the cap to Jennifer Ouellette.)
Wednesday, March 28, 2018
I read this before at some point, and it's still really funny now. (And also way too close to the truth.)
Tuesday, March 27, 2018
It's always nice to be analyzed (for my tweeting behavior) alongside luminaries like Katy Perry, Shaquille O'Neal, and Steve Martin. Lots of my peeps from network and data science are also put under the data-analytic microscope (or perhaps I should write 'mesoscope') on this page.
I had this posted on my door at Georgia Tech when I was a postdoc, and I found the note a year ago today when I was going through an old spiral notebook.
As a @Caltech undergraduate, I taught a probability course (Math 1d) and introduced freshmen to the glories of generating functions.— Mason Porter (@masonporter) March 27, 2018
My exam instructions included a line like: "You may also use a note from your mother, though you won't need one."
One student took me up on it. pic.twitter.com/I2Ocif9ttA
Sunday, March 25, 2018
The title of Se-Wook's thesis is Complex Contagions with Lazy Adoption. You can read about some of Se-Wook's work in our joint paper, which was published recently in Chaos.
Tuesday, March 20, 2018
I will somehow deal with the fact that I am not allowed to have coffee on campus. :)
Sunday, March 18, 2018
(Tip of the cap to Lior Pachter.)
(Tip of the cap to Kerstin Nordstrom.)
Saturday, March 17, 2018
I like the cover of "The Magic Ring". :)
(Tip of the cap to Gabrielle Birkman.)
Here's a Fun (Alternative) Fact: The Society for Industrial and Applied Mathematics used to be known as "Society for Impure Mathematics" (SIM), because those of us who do applied mathematics are less pure than other types of mathematicians, bless their hearts.
But perhaps this great organization really ought to change its name to "Society for Impure Mathematics", to appease the theoretical mathematicians who like to call themselves "pure" mathematicians.
As you may have gathered, I find the phrasing "pure mathematics" to be incredibly demeaning towards applied mathematics and applied mathematicians. (The term "unadulterated mathematics" is even worse, so I suppose that my subject of choice is "adulterated mathematics".) I really dislike being considered impure, by implication of the term in use. "Pure mathematics" should really be called "theoretical mathematics", just like in every other science.
Additionally, here are two of my tweets on this and related subjects.
From now on, can we say "theoretical mathematics" instead of "pure mathematics"? It's much less obnoxious.— Mason Porter (@masonporter) August 25, 2017
From me, an impure mathematician
The Mathematics Subject Classification (MSC), required on the AMS cover sheet when applying for US mathematics faculty jobs, is very poorly suited for classifying applied mathematicians and leads to interdisciplinary applicants falling through the cracks.https://t.co/zcJ0vmArv4 pic.twitter.com/6KC4pg2f1y— Mason Porter (@masonporter) December 2, 2017
Update: I corrected the acronym (I had written "SIP"), because apparently I am having a problem with English today.
Update: If we want to preserve the acronym SIAM and don't mind a bit of redundancy, it can stand for "Society for Impure and Adulterated Mathematics". :)
Snakes appear to move. pic.twitter.com/HggajNQsHY— Akiyoshi Kitaoka (@AkiyoshiKitaoka) March 17, 2018
(Tip of the cap to Maggie Koerth-Baker.)
Friday, March 16, 2018
Here is an old article on pencil-tip fracture (by Henry Petroski). The picture below, which comes from an even earlier article, sets up the the geometry of a pencil tip.
(I was thinking about this because a 'Number 2' pencil showed up in The Grimm Legacy, which I am currently reading.)
Thursday, March 15, 2018
I have a pet peeve in the above obituary: Don't write sentences like "He wrote countless books, articles, and book reviews imbued with his personal perspective." in the obituary of a mathematician, especially if he is an analyst (with much work in numerical analysis, in this case). Trust me: it's countable (and, actually, it's finite).
For most of us, we'll be more familiar with the many essays and (especially) book reviews that Davis wrote for SIAM News.
(Tip of the cap to the SIAM Twitter account.)
I’ll soon be giving what amounts to a tutorial for my UCLA Ph.D. students, who will be embarking on writing papers, and — as I was thinking about what materials to prepare — my mind went to a dark, sarcastic place.— Mason Porter (@masonporter) March 15, 2018
(Inspiration from "Title of the Song" by Da Vinci's Notebook.) pic.twitter.com/N1n3xSY6xr
Update: It turns out that I did this so quickly that I mixed my Oxford and UCLA affiliations. Oops.
Tuesday, March 13, 2018
This is quite a correction for the misspelling of one author's name by a single letter. pic.twitter.com/PJgwmETSIj— Retraction Watch (@RetractionWatch) March 13, 2018
(Tip of the cap to Nalini Joshi, whose 'liking' of this tweet led me to find it.)
Saturday, March 10, 2018
I have a key question: Where are the best places to inflict lightning bolts on people?
In conclusion, come get some!
(Tip of the cap to Gabrielle Birkman, who indicates that there are places to get banana peels and turtle shells.)
The Buffy social network: slayage and love links. https://t.co/xwQ0DoKpAG— Peter Sheridan Dodds (@peterdodds) March 11, 2018
This figure is definite fodder for talks. Also, if somebody sets up the adjacencies, we should compute some centrality and versatility measures.
Friday, March 09, 2018
You've got to get the important stuff right.
(My submitted feedback also included more substantial comments.)
I also told the lecturer about this in person, of course. :)
It was just a typo, but I may have to adopt this as a new word for when somebody does something artificial in science.
Example usage: "Those data were estimated scientificially to follow a power law."
Wednesday, March 07, 2018
Quoting the project page: "In February 2018, women mathematicians from all over the world responded to a call for clips in which they were asked to introduce themselves. The result includes 146 clips of 243 women mathematicians from 36 different countries and speaking 31 different languages. Supported by the Committee for Women in Mathematics of the International Mathematical Union."
Take a look at the video!
I met Eugénie, a fellow Somervillian, at last summer's Somerville mathematics reunion (and informal Erdmann-fest). I just found out that she is also a fellow Project NExTer (i.e., a fellow 'dot').
Tuesday, March 06, 2018
And now I see this article, which predominantly consists of an interview with nonlinear dynamicist (and pioneer of chaos) Jim Yorke, including discussions about both mathematical chaos and hyperchaos.
Here is how the part with Yorke begins: "That's not chaos, according to James A. Yorke, Distinguished University Professor of Mathematics and Physics at the University of Maryland at College Park." It goes on from there.
Just think about it: Jim Yorke, an expert in chaotic dynamics, was interviewed by CNN about Donald Trump, precisely because of the former's expertise in mathematical chaos. Yup, we've gone full Illuminati.
(Tip of the cap to Bruno Eckhardt and fuzzy sweatshirt particle.)
Monday, March 05, 2018
Friday, March 02, 2018
It's tempting to fixate on specific professors or features of departments, and to get sold by their pitches. And that all matters. But you never know how your research interests will change over time. What remains constant and critical is the need for caring and supportive peers.— Lego Grad Student (@legogradstudent) March 2, 2018
Reaction: YES! YES! A million times YES! (And, for the top tweet, I would change "seriously consider" to "absolutely go to".)
P.S. Lego Grad Student is awesome.
Thursday, March 01, 2018
(Some — most? — versions of the song actually have the line "One is the number divided by two", which is even worse, because of the "the".)
I suppose that this doesn't bother anybody else?
I was looking at Dwight Barkley's Wikipedia page, and I noticed that apparently he is also known for deriving an equation to estimate how long it will be until a child in a car asks the question "are we there yet?"
You can read about it (and see the equation) in this short article.
Title: Complex Contagions with Timers
Authors: Se-Wook Oh and Mason A. Porter
Abstract: There has been a great deal of effort to try to model social influence—including the spread of behavior, norms, and ideas—on networks. Most models of social influence tend to assume that individuals react to changes in the states of their neighbors without any time delay, but this is often not true in social contexts, where (for various reasons) different agents can have different response times. To examine such situations, we introduce the idea of a timer into threshold models of social influence. The presence of timers on nodes delays adoptions—i.e., changes of state—by the agents, which in turn delays the adoptions of their neighbors. With a homogeneously-distributed timer, in which all nodes have the same amount of delay, the adoption order of nodes remains the same. However, heterogeneously-distributed timers can change the adoption order of nodes and hence the “adoption paths” through which state changes spread in a network. Using a threshold model of social contagions, we illustrate that heterogeneous timers can either accelerate or decelerate the spread of adoptions compared to an analogous situation with homogeneous timers, and we investigate the relationship of such acceleration or deceleration with respect to the timer distribution and network structure. We derive an analytical approximation for the temporal evolution of the fraction of adopters by modifying a pair approximation for the Watts threshold model, and we find good agreement with numerical simulations. We also examine our new timer model on networks constructed from empirical data.
Tuesday, February 27, 2018
In fact, I think this error is a feature of the book, rather than a bug (especially given that I automatically think of Paul Erdős). By the way, the book itself is awesome, so go take a look at it. Here is a screenshot of the erratum.
(Tip of the cap to my Ph.D. student Yacoub Kureh for pointing this out to me in our meeting today. This erratum is an instant classic.)
20 Very Obscure, Very Specific Ancient Jobs eg "Nob Thatcher - Also spelled knob thatcher, this delightful occupation may sound like a Medieval insult, but was the term for a wig-maker." https://t.co/iBrkPdUWWK— Jennifer Ouellette (@JenLucPiquant) February 27, 2018
Sunday, February 25, 2018
Gummy Bear genetics pic.twitter.com/XEkHuoSAz2— Scott Kerr (@scott_kerr) February 25, 2018
Thursday, February 22, 2018
Alan Kay's 1972 vision of the personal computer: "Let's just do it!" Fundamental design principles of computation, robustness & evolvability, anticipates issues in augmented intelligence & AI-human cooperation (user just a process, too) ht @michael_nielsen https://t.co/8Wn3pXQNkl pic.twitter.com/BC1oW9883N— Jessica Flack (@C4COMPUTATION) February 21, 2018
Title: Opinion Formation and Distribution in a Bounded-Confidence Model on Various Networks
Authors: X. Flora Meng, Robert A. Van Gorder, and Mason A. Porter
Abstract: In the social, behavioral, and economic sciences, it is important to predict which individual opinions eventually dominate in a large population, whether there will be a consensus, and how long it takes for a consensus to form. Such ideas have been studied heavily both in physics and in other disciplines, and the answers depend strongly both on how one models opinions and on the network structure on which opinions evolve. One model that was created to study consensus formation quantitatively is the Deffuant model, in which the opinion distribution of a population evolves via sequential random pairwise encounters. To consider heterogeneity of interactions in a population along with social influence, we study the Deffuant model on various network structures (deterministic synthetic networks, random synthetic networks, and social networks constructed from Facebook data). We numerically simulate the Deffuant model and conduct regression analyses to investigate the dependence of the time to reach steady states on various model parameters, including a confidence bound for opinion updates, the number of participating entities, and their willingness to compromise. We find that network structure and parameter values both have important effects on the convergence time and the number of steady-state opinion groups. For some network architectures, we observe that the relationship between the convergence time and model parameters undergoes a transition at a critical value of the confidence bound. For some networks, the steady-state opinion distribution also changes from consensus to multiple opinion groups at this critical value.
Wednesday, February 21, 2018
My mathematical haiku are part of a collection of haiku published in Journal of Humanistic Mathematics in January 2018: https://t.co/ZbG0JEBgL6— Mason Porter (@masonporter) February 22, 2018
(Yes, even my haiku sometimes include sarcasm.) pic.twitter.com/ogPXYmmR9W
(Thanks to Paul Glendinning for the Twitter 'mention', from which I learned that my haiku made it into the article.)
I'd try to link to a relevant website, except that my internet connection at the airport is glacially slow, so I'm not going to even try for now. We'll be formulating some forward-looking big problems in network neuroscience to think about together and then hopefully start thinking deeply about and trying to solve.
Update: Here is the link to our working group.
Tuesday, February 20, 2018
Alarming Comics #1 (1957) pic.twitter.com/tn7wzIxKlC— Panel Pulp (@panelpulp) February 19, 2018
And this was with only a 4th dimension!
This will be great fodder for some math and physics talks... "NO! Don't enter that manifold!"
(Tip of the cap to James Gleick.)
Monday, February 19, 2018
The sentence in the abstract reads as follows: Building on the seminal but laconic findings of Adachi, we show that the deviation from second order can be used to rigorously determine the Stokes lines and therefore the region of the space that should be removed.
I think I need to steal the first part of that sentence, and I know that I have felt that way on many occasions (e.g., with respect to work by Nesterenko) in my career.
"Neither Global nor Local: Heterogeneous Connectivity in Spatial Network Structures of World Migration"
Title: Neither Global nor Local: Heterogeneous Connectivity in Spatial Network Structures of World Migration
Authors: Valentin Danchev and Mason A. Porterc
Abstract: For a long time, geographic regions were considered the dominant spatial arbiter of international migration of people. However, since the late 1970s, many scholars have argued that movements reach beyond contiguous regions to connect distant, dispersed, and previously disconnected countries across the globe. The precise structure of world migration, however, remains an open question. We apply network analysis that incorporates spatial information to international migration-stock data to examine what multilateral structures of world migration have emerged from the interplay of regional concentration (local cohesion)and global interconnectedness (global cohesion) for the period 1960–2000. In the world migration network (WMN), nodes represent countries located in geographic space, and edges represent migrants froman origin country who live in a destination country during each decade. We characterize the large-scale structure and evolution of the WMN by algorithmically detecting international migration communities (i.e., sets of countries that are densely connected via migration) using a generalized modularity function for spatial, temporal, and directed networks. Our findings for the whole network suggest that movements in the WMN deviate significantly from the regional boundaries of the world and that international migration communities have become globally interconnected over time. However, we observe a strong variability in the distribution of strengths, neighborhood overlaps, and lengths of migration edges in the WMN. This manifests as three types of communities: global, local, and glocal. We find that long-distance movements in global communities bridge multiple non-contiguous countries, whereas local (and, to a lesser extent, glocal) communities remain trapped in contiguous geographic regions (or neighboring regions) for almost the whole period, contributing to a spatially fragmented WMN. Our findings demonstrate that world migration is neither regionally concentrated nor globally interconnected, but instead exhibits a heterogeneous connectivity pattern that channels unequal migration opportunities across the world.