Author(s): Jakob J. Metzger, Ragnar Fleischmann, and Theo Geisel

Waves traveling through random media exhibit random focusing that leads to extremely high wave intensities even in the absence of nonlinearities. Although such extreme events are present in a wide variety of physical systems and the statistics of the highest waves is important for their analysis and...

[Phys. Rev. Lett. 112, 203903] Published Fri May 23, 2014

Author(s): D. Schlippert, J. Hartwig, H. Albers, L. L. Richardson, C. Schubert, A. Roura, W. P. Schleich, W. Ertmer, and E. M. Rasel

A new experiment using matter-wave interferometry confirms that different atoms free fall in gravity at the same rate.

[Phys. Rev. Lett. 112, 203002] Published Thu May 22, 2014

Author(s): Yanqing Hu, Shlomo Havlin, and Hernán A. Makse

Social networks experience viral spreading, in which a small group of pioneering individuals can popularize movements and ideas. Scientists use physical modeling and empirical validation to trace how networks shrink and grow depending on the actions of both random nodes and well-connected nodes.

[Phys. Rev. X 4, 021031] Published Tue May 20, 2014

Author(s): O. Lozan, M. Perrin, B. Ea-Kim, J. M. Rampnoux, S. Dilhaire, and P. Lalanne

Experiments looking at surface-bound light emanating from a thin slit find less of the light is absorbed by the surface material than expected.

[Phys. Rev. Lett. 112, 193903] Published Fri May 16, 2014

Author(s): Shang-Chi Jiang, Xiang Xiong, Yuan-Sheng Hu, Yu-Hui Hu, Guo-Bin Ma, Ru-Wen Peng, Cheng Sun, and Mu Wang

Metamaterials, artificial structures with unexpected properties, only function over a limited spectral window. Scientists have recently determined that the technique of combining a metallic metamaterial with a dielectric interlayer creates a device that modulates light over a wide range of frequencies.

[Phys. Rev. X 4, 021026] Published Thu May 15, 2014

Anthropogenic electromagnetic noise disrupts magnetic compass orientation in a migratory bird

Nature 509, 7500 (2014). doi:10.1038/nature13290

Authors: Svenja Engels, Nils-Lasse Schneider, Nele Lefeldt, Christine Maira Hein, Manuela Zapka, Andreas Michalik, Dana Elbers, Achim Kittel, P. J. Hore & Henrik Mouritsen

Electromagnetic noise is emitted everywhere humans use electronic devices. For decades, it has been hotly debated whether man-made electric and magnetic fields affect biological processes, including human health. So far, no putative effect of anthropogenic electromagnetic noise at intensities below the guidelines adopted by the World Health Organization has withstood the test of independent replication under truly blinded experimental conditions. No effect has therefore been widely accepted as scientifically proven. Here we show that migratory birds are unable to use their magnetic compass in the presence of urban electromagnetic noise. When European robins, Erithacus rubecula, were exposed to the background electromagnetic noise present in unscreened wooden huts at the University of Oldenburg campus, they could not orient using their magnetic compass. Their magnetic orientation capabilities reappeared in electrically grounded, aluminium-screened huts, which attenuated electromagnetic noise in the frequency range from 50 kHz to 5 MHz by approximately two orders of magnitude. When the grounding was removed or when broadband electromagnetic noise was deliberately generated inside the screened and grounded huts, the birds again lost their magnetic orientation capabilities. The disruptive effect of radiofrequency electromagnetic fields is not confined to a narrow frequency band and birds tested far from sources of electromagnetic noise required no screening to orient with their magnetic compass. These fully double-blinded tests document a reproducible effect of anthropogenic electromagnetic noise on the behaviour of an intact vertebrate.

An accident waiting to happen

Nature 509, 7500 (2014). doi:10.1038/509259a

The release of radioactive material at a US nuclear-waste repository reveals an all-too-common picture of complacency over safety and a gradual downgrading of regulations.

Homophobia and HIV research: Under siege

Nature 509, 7500 (2014). http://www.nature.com/doifinder/10.1038/509274a

Author: Linda Nordling

A wave of anti-gay laws and homophobia in Africa is hampering efforts to study and curb the spread of HIV.

What if Au Bon Pain lost this lawsuit and had to pay the plaintiff $2 undecillion?

—Kevin Underhill

The bakery-cafe chain Au Bon Pain (with a few other organizations) is being sued. This is how much money the person suing them is demanding:

This is how much sellable stuff there is in the world:

This is the estimated economic value of all goods and services produced by humanity since we first evolved:

Even if Au Bon Pain conquers the planet and puts everyone to work for them from now until the stars die, they wouldn't make a dent in the bill.

Maybe people just aren't that valuable. The EPA currently values a human life at $8.7 million, although they go to great lengths to point out that technically this is not actually the value any specific person places on another person's individual life.[1]Note that they don't say whether they assume that amount would be higher or lower. In any case, by their measure, the total value we place on all the world's humans is only about $60 quadrillion.[2]The world's combined oil reserves are only worth a few hundred trillion, which suggests that purely from an accounting standpoint, the "no blood for oil" slogan makes a lot of sense.

But while people may be worthless,[3]I'm rounding down. we're hardly all there is on the planet. Out of all the Earth's atoms, only 1 out of every 10 trillion is part of a human.

The Earth's crust contains a bunch of atoms,^{[citation needed]} some of which are valuable. If you extracted all the elements, purified them,[4]This is just one of many reasons that this idea wouldn't make sense in practice. The reason many elements (like U-235) are valuable is that it's hard to manufacture or purify them, not just because they're rare. and sold them, the market would crash.[5]Both in the sense that the supply would cause a drop in prices, and the sense that the market is like 20 miles above the mantle and you just removed the crust supporting it. But if you somehow sold them at their current market price, they would be worth ...

Oddly, most of this value comes from potassium and calcium, and most of the rest comes from sodium and iron. If you're going to sell the Earth's crust for scrap, those are probably the ones you should sift out.

Sadly, even selling the crust for scrap doesn't get us close to the numbers we need.

We could include the core,[6]It's down there. which is iron and nickel with a dash of precious metals, but it turns out it wouldn't help. The amount demanded from Au Bon Pain is just too large. In fact, an Earth made of solid gold wouldn't be enough. The Sun's weight in platinum wouldn't be, either.

By weight, the single most valuable thing that's been bought and sold on an open market is probably the Treskilling Yellow postage stamp. There's only one known copy of it, and in 2010 it sold for \$2,300,000. That works out to about \$30 billion per kilogram of stamps. If the Earth's weight were entirely postage stamps, it would still not be enough to pay off Au Bon Pain's potential debt.[7]Also, the stamps would probably be less valuable now that there is literally an entire planet of them, but that's the least of Au Bon Pain's problems.

If Au Bon Pain & co decided to be intentionally difficult, and pay their debt entirely in pennies, they would form a sphere that would squeeze inside the orbit of Mercury.[8]The fate of this sphere of pennies is left as an exercise for the reader. The fate of Mercury is that it would fall into the pennies and disintegrate. The bottom line is that paying this settlement would be, in almost any sense of the word, impossible.

Fortunately, Au Bon Pain has a better option.

Kevin, who asked this question, is a lawyer and author of the legal humor blog that reported on the Au Bon Pain case.[9]And which we encountered in Question #90. He told me that the world's most highly-paid lawyer—on an hourly basis—is probably former Solicitor General Ted Olson, who recently disclosed in bankruptcy filings that he charges $1,800 per hour.

Suppose there are 40 billion habitable planets in our galaxy, and every one of them hosts an Earth-sized population of 7 billion Ted Olsons.

If Au Bon Pain hired every Ted Olson in the galaxy to defend them in this case, and had them all work 80-hour weeks, 52 weeks a year, for a thousand generations[10]This scenario assumes that the former Solicitor General reproduces asexually....

... it would still cost them less than if they lost.

Article

According to Noether’s theorem, every symmetry of a dynamical evolution implies a conservation law. Marvian and Spekkens show that this theorem is deficient for certain types of quantum dynamics, and they propose measures of the extent to which a quantum state breaks a symmetry.

Nature Communications doi: 10.1038/ncomms4821

Authors: Iman Marvian, Robert W Spekkens

grazie per tutto il disagio, comunque

Article

Bloch oscillations—oscillatory motions of wave packets in periodic potentials acting under constant forces—have been observed in semiconductor superlattices and photonic waveguide arrays. Here, the authors extend these ideas to plasmonics to observe Bloch oscillations and discrete diffraction.

Nature Communications doi: 10.1038/ncomms4843

Authors: A. Block, C. Etrich, T. Limboeck, F. Bleckmann, E. Soergel, C. Rockstuhl, S. Linden

Article

The use of photonic crystals to trap atoms on a chip offers unique possibilities for atom–light interactions. Advancing towards this goal, the authors realize photonic crystal waveguides where the electronic transition frequencies of localized caesium atoms are aligned with the band edges of the waveguides.

Nature Communications doi: 10.1038/ncomms4808

Authors: A. Goban, C.-L. Hung, S.-P. Yu, J.D. Hood, J.A. Muniz, J.H. Lee, M.J. Martin, A.C. McClung, K.S. Choi, D.E. Chang, O. Painter, H.J. Kimble

“Evolution of Complexes from LEGO™ Bricks in a Washing Machine“, by Ingo Althöfer, appears in the special Cloning & Evolution issue of the Annals of Improbable Research. (The article is also online.) It begins:

Disclaimers: This work has not been supported by the LEGO Group or any other brick toy company This work has not been sponsored by the Miele domestic appliance and machine manufacturing company. This work has not been supported by the artist Piet Mondrian.

Some people use their washing machine to clean LEGO bricks. No surprise, it works. But more than just cleaning occurs. Typically during the washing process, some of the bricks join together randomly, forming complexes. I observed the phenomenon (see Figure 1), and became curiously obsessed. I spent the next nineteen and a half weeks conducting many brick washing sessions.…

Author(s): E. A. Jagla, François P. Landes, and Alberto Rosso

In many complex systems a continuous input of energy over time can be suddenly relaxed in the form of avalanches. Conventional avalanche models disregard the possibility of internal dynamical effects in the interavalanche periods, and thus miss basic features observed in some real systems. We addres...

[Phys. Rev. Lett. 112, 174301] Published Wed Apr 30, 2014

The first large-scale measurements of the way humans play Rock-Paper-Scissors reveal a hidden pattern of play that opponents can exploit to gain a vital edge.

If you’ve ever played Rock-Paper-Scissors, you’ll have wondered about the strategy that is most likely to beat your opponent. And you’re not alone. Game theorists have long puzzled over this and other similar games in the hope of finding the ultimate approach.

Nature Physics 10, 394 (2014). doi:10.1038/nphys2927

Authors: Bo Peng, Şahin Kaya Özdemir, Fuchuan Lei, Faraz Monifi, Mariagiovanna Gianfreda, Gui Lu Long, Shanhui Fan, Franco Nori, Carl M. Bender & Lan Yang

Nature Physics 10, 331 (2014). doi:10.1038/nphys2963

Author: Mark Buchanan

Nature Methods 11, 467 (2014). doi:10.1038/nmeth.2937

Authors: Martin Krzywinski & Naomi Altman

Nonparametric tests robustly compare skewed or ranked data.

Author(s): Henning Krüsemann, Aljaž Godec, and Ralf Metzler

Aging, the dependence of the dynamics of a physical process on the time ta since its original preparation, is observed in systems ranging from the motion of charge carriers in amorphous semiconductors over the blinking dynamics of quantum dots to the tracer dispersion in living biological cells. Her...

[Phys. Rev. E 89, 040101] Published Mon Apr 28, 2014