Archive for 'Improbable investigators'

Up in the air, junior bird man: from Ireland to Africa, lawnmower-ly

Sunday, August 14th, 2016

With a spirit somewhat akin to that of Ig Nobel Prize winner Troy (built a suit of armor to protect against grizzly bears) Hurtubise, comes “One man’s dream project to fly from Ireland to Africa by lawnmower gets under way this week“. The story is reported, with that headline, in The Journal:


A FEW MONTHS back, we brought you the story of 52-year-old Oisín Creagh – the Dublin-born, Cork-based architect with a slightly-odd project on the go.

Yes, Oisín is a paramotorist – a form of aviation basically involving the equivalent of a lawnmower engine and a parachute and precious little else. He’s planning to fly one of these things to north Africa, a trip-distance of 3,000 kilometres, to raise money for Gorta-Self Help Africa and its operations in drought-ravaged Ethiopia.

And it all kicks off this week.

Oisín is set to fly his ‘wing’ (as a paramotor is known within the sport) across the English channel before turning south and heading across the Straits of Gibraltar to Africa.

The entire trip should take him a month, flying at an average of 1,500 feet, in three-hour, 150 km bursts.

BONUS: A performance of the beloved song “Up in the Air, Junior Birdmen!“:

Mathematics, Failure, and the World’s Most Famous Walking Event

Friday, August 12th, 2016

Have you ever calculated your chances of being allowed to participate in an event? As at least one study demonstrates, you might be surprised.
The 100th International Four Days Marches Nijmegen, the world’s most famous walking event, took place last month. Over 40,000 people participated, and there are various ways that somebody can be allowed to participate in this march in a given year. As Antoine AmarilliMarc BeunardeauRémi Géraud, and David Naccache demonstrated mathematically using probability theory (see their recent preprint) when pondering the rules in 2013, until a recent rules change, the best chance of being allowed to participate in the 100th event would occur if one failed that year’s event. See the transition graph below from Fig. 1 of their paper.




Nominative determinism: Dr. No Kwak

Sunday, July 3rd, 2016

In the United States, and in some other countries, no doctor wants to be called “a quack“. (An entire web site called Quackwatch devotes itself to reporting on doctors who are, in the view of Quackwatch, quacks.)

Doctors who fear being called “a quack” can but envy No Kwak, MD. Everyone can happily agree that this physician is No Kwak.

NoKwakDr. No Kwak practices medicine in the state of New York, specializing in vascular and interventional radiology.  Dr. No Kwak co-authored the study “Case Report: Two Cases of Uretero-Iliac Artery Fistula Managed with Endovascular Therapy,” which was published in 2015 in the OMICS Journal of Radiology. So far as we have determined, Dr. No Kwak is the only physician whom that journal has ever specifically said is No Kwak.

Dr. No Kwak is affiliated with Glen Cove Hospital, with Huntington Hospital, with Lenox Hill Hospital, with Long Island Jewish Forest Hills, with Long Island Jewish Medical Center, with Long Island Jewish Valley Stream, with North Shore University Hospital, with Plainview Hospital, with Southside Hospital, and with Syosset Hospital. So far as we have determined, Dr. No Kwak is the only physician whom each and every one of those institutions has ever specifically said is No Kwak.

(Thanks to Ivan Oransky, who has often brought quacks to our attention, for bringing No Kwak to our attention.)

The Hercules Number: How a Dimensionless Physical Parameter Got Its Name

Tuesday, June 14th, 2016

I did not conceive or give birth to the Hercules Number. But I did name it. Here’s the story.

In science and mathematics, we often get to name things. To help with exposition, sometimes we essentially have to name them, because it can help us do a better job of explaining things. In fact, we also enjoy naming things. To borrow some words from the computer game Beyond Zork, we often want a scientific idea to “bask in the glow of a new-forged synonym.”

And we get to name all sorts of things—concepts, theorems, examples, equations, groups, graphs, manifolds, numbers, physical parameters, and more. Sometimes we name them after people—ideally after somebody other than ourselves, and occasionally even after the person who actually had the idea first—and other times we get to be more creative. Naturally, the same object can go by more than one name, especially when multiple scientific fields are involved. On occasion, we fail miserably in our naming adventures. In abstract algebra, for example, there are so-called extra special groups. (My abstract algebra professor at Caltech couldn’t tell us about them without giggling over the name, so that is how you should read the previous sentence.)

One of the peculiar traditions in continuum mechanics (and especially in fluid mechanics) is the incessant naming of dimensionless physical parameters: the Reynolds number, the Rayleigh number, the Prandtl number, the Péclet number, and myriad others. If one states all of these numbers quickly one after another, one would almost have a George Carlin routine, except with a lot less cussing.

Illustration of (a) why it is really hard to separate two interleaved books and (b) the dimensionless parameter now known as the Hercules number. This is figure 2, and the associated caption, in a quick study in Phys. Today 69, 6, 74 (2016).

Illustration of (a) why it is really hard to separate two interleaved books and (b) the dimensionless parameter now known as the Hercules number. [This illustration is Figure 2, and its associated caption, from a quick study in Phys. Today 69, 6, 74 (2016).]

 A recently-introduced dimensionless parameter that caught my eye was the Repunzel number from ponytail physics (the subject of the 2012 Ig Nobel Prize in physics). And the naming of this number was very much on my mind a few months ago when I wrote an entry in the Improbable Research blog about a very cool new paper in Physical Review Letters (PRL) on how hard it is to pull apart two interleaved phone books. The authors of the paper had introduced a dimensionless parameter, but it didn’t have a name. And it clearly required a Herculean effort to pull apart those phone books, so I knew what name I wanted to attach to that dimensionless parameter. So with inspiration that was part Herculean, part Oxonian (I have spent the last 9 years in Oxford surrounded by applied mathematicians who study continuum mechanics), and part Repunzelian, I wrote the following sentence:

Restagno and colleagues also fit the data to a curve of force versus a dimensionless amplification parameter—following the continuum-mechanics tradition of using cute names for dimensionless parameters, let’s call it the “Hercules number”—that depends on the number of pages, the page thickness, and the size of the overlap region between the books.

The authors of the PRL paper enjoyed the new monicker—one might even say that the Hercules number was basking in the glow of its new-forged synonym—and they mentioned it to me via Twitter. And now Kari Dalnoki-VeressThomas Salez, and Frédéric Restagno (three of the authors of the original PRL paper) have written a “quick study” in the June 2016 issue of Physics Today. As you’ll notice, they use the name Hercules number, and of course I am very pleased about that. I am always happy to contribute to mathematics and physics with my wit and snark.

Bonus: When it comes to naming a scientific idea after a person (and whether or not one has chosen the correct one), I would like to invoke the “Three Laws of Discovery” that are listed among the quotations on Ig Nobel laureate Michael Berry’s website:

  1. Discoveries are rarely attributed to the correct person. (Arnold’s Law, which is of course self-referential)
  2. Nothing is ever discovered for the first time. (Berry’s Law)
  3. Everything of importance has been said before by someone who did not discover it. (Whitehead’s Law, though I am not sure which Whitehead it is. I assume it is one of the mathematical ones.)

Another Bonus: The story of the penguin diagram in nuclear physics is absolutely lovely. (That name came about substantially through the efforts of Melissa Franklin, whom you may have heard on Improbable Research podcasts.)

A Third Bonus: In mathematics, there is a problem called the Ten Martini Problem.

Quantifying the Smell of Urban Areas

Tuesday, June 7th, 2016

Data analysis has led to numerous insights into a diverse variety of complex systems. A new paper that gives a whiff of such insights is The Emotional and Chromatic Layers of Urban Smells by Daniele Quercia of Bell Labs, Luca Maria Aiello of Yahoo Labs, and Rossano Schifanella of University of Turin.

Quercia et al. write the following in their abstract:

People are able to detect up to 1 trillion odors. Yet, city planning is concerned only with a few bad odors, mainly because odors are currently captured only through complaints made by urban dwellers. To capture both good and bad odors, we resort to a methodology that has been recently proposed and relies on tagging information of geo-referenced pictures. In doing so for the cities of London and Barcelona, this work makes three new contributions. We study 1) how the urban smellscape changes in time and space; 2) which emotions people share at places with specific smells; and 3) what is the color of a smell, if it exists. Without social media data, insights about those three aspects have been dicult to produce in the past, further delaying the creation of urban restorative experiences.

As we can see from this work, no matter whether one is spending time in London or in Barcelona, a city by any other name would smell just as… uh, sweet. And perhaps be associated with just as much joy, trust, anticipation, or surprise?


A figure from the paper by Quercia et al. that examines the correlation between various types of emotions and various types of smells.

Clearly, this is research that we need to savor.