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Physics Week in Review (Pi Day Edition): March 14, 2015

Today we celebrate the Pi Day of the Century: March 14, 2015, is the first five digits of pi, or 3.1415.  It’s also Albert Einstein’s birthday, so Sean Carroll reminded us how they are intimately connected; yes, Pi has something to do with gravity.

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Today we celebrate the Pi Day of the Century: March 14, 2015, is the first five digits of pi, or 3.1415. It's also Albert Einstein's birthday, so Sean Carroll reminded us how they are intimately connected; yes, Pi has something to do with gravity. So did Rhett Allain over at Dot Physics: Why is Pi squared about equal to g (9.8 N/kg)? There actually is a reason. Related: Don’t Recite Digits to Celebrate Pi. Recite Its Continued Fraction Instead. Also: American Pi: Why the Day Belongs to the U.S. (and Belize): "because they are the only ones (if Wikipedia is correct) to shorthand their date format so that it can match the first few digits of pi (3.1415), or March 14, 2015." But Wales has its own claim to Pi, per Alex Bellos:

"Events in Wales have been encouraged by the Welsh government, which declared it Pi Day Cymru as a way of honouring the Anglesey-born mathematician William Jones, who came up with the idea of pi in 1706. Jones was not the first person to realise that the circumference of a circle divided by the diameter is a number that defies easy calculation. But he was the first to denote the ratio by the symbol π, suggesting it in a book as an abbreviation of either the word periphery or perimeter."

The Perimeter Institute marked the occasion by profiling a few Pioneering Women of Physics; io9 did the same with These 17 Women Changed The Face Of Physics. Related: Hypatia and the Double-Edged Sword of Women’s Science History. "What a bizarre, wonderful, utterly unconventional human being Hypatia must have been. Yet her accomplishments in life will always be overshadowed by the brutality of her death. Just as she represents the reality of female genius, she is also a reminder that it can come at a hefty price." Also: No Name, No Patent: Acknowledging the Black Women that Science Has Exploited. Bonus: a classic xkcd comic with Zombie Marie Curie. Finally: Find Inspiration From These Women Working With Science In Public.


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He ate all the pi : Japanese man memorises π to 111,700 digits. Akira Haraguchi, 69, is a legend among memory masters, having memorised more of pi’s digits than anyone else. And courtesy of the Perimeter Institute, we have this charming video of "standup mathematician" Matt Parker and PI's Tibra Ali going head-to-head in a battle to concisely describe the ratio of a circle's circumference to its diameter.

Experiments record "splash" events from the injector tests at the Large Hadron Collider. Related: Large Hadron Collider ramps up to shed light on dark matter. LHC will run at double its previous energy, smashing protons to open up the subatomic world and look for more varieties of Higgs boson. Also: Number-crunching the Higgs boson: meet the world's largest distributed computer grid.

Mathematicians Chase Moonshine’s Shadow: Researchers are on the trail of a mysterious connection between number theory, algebra and string theory.

Gamma Rays May Provide a Clue on Dark Matter.

Freeze! Watching alloys change from liquid to solid could lead to better metals. "If you put a camera in the ice machine and watched water turn into ice, the process would look simple. But the mechanism behind liquids turning to solids is actually quite complex, and understanding it better could improve design and production of metals." Related: Shape-Shifting Metal is a Tiny T-1000 Terminator IRL. "Researchers at Tsinghua University in Beijing, China have discovered a synthetic liquid metal motor that eats aluminum for fuel and alters its form to passes through various environments."

The Man Who Is Obsessed with Glass: “Glass is surprising because it’s so rigid, but when you measure its molecular properties, it looks exactly like a liquid.”

What Your Bones Have In Common With The Eiffel Tower. "The Eiffel tower is incredibly well optimized to do what it was designed to do, to stand tall and stand strong, while using a minimum of material. Rather than hide its inner workings with a facade, Eiffel exposed the skeleton of his masterpiece. In doing so, he revealed its “hidden rules of harmony”, many of the same rules that give your skeleton its lightweight strength."

The secret of wrinkling, folding, and creasing. New research provides a general formula for understanding how layered materials form different surface patterns.

Inside Graphene City, Birthplace of a Wonder Material. Related: From Baby Teeth to Aerogel: Take a Tour of a Library of Materials in London.

Astronomers Create 3-D Printed Model of Colliding Stellar Winds. Displaying the data from complex astrophysical simulations is always hard. So astronomers came up with a solution: they 3-D printed the data so they could hold it in their hands.

Fictional Images of the Universe Made From Scanning Household Items and Food by Navid Baraty. "Using an Epson photo scanner, Baraty carefully positions various household items, many of which are edible, on the document table. Cooking ingredients like baking soda, sugar and cinnamon act as distant stars and nebulas while glasses containing milk, water and food coloring create the planets. Once everything is aligned properly Baraty hits the scan button."

Why does E=mc^2? Einstein’s most famous equation works out more neatly than you’d expect. Related: You’ve heard of Einstein’s E=mc2, but what does it mean?

This year marks the 100th anniversary of Einstein's Theory of Relativity, so the American Institute of Physics' history celebrates with a nifty slideshow. Related: Of Relativity and The Other Man: Ruminations on a Classic Lecture by Arthur Eddington. "The particulars of exactly how space and time are warped for a particular observer, the specific shape acquired by spacetime as it curves around matter - those are details. The richness of the theory comes from no one single scenario, but the fact that it envelops an almost inexhaustible number of possibilities each with its own set of unique characteristics." Also: A Very Early Bibliography on the Theory of Special Relativity.

What nefarious goings-on lurk inside a quantum-mechanical wave function?

Is anything in the universe truly random? After centuries pondering whether we are fortune's fools, we are still struggling to work out if the cosmos is predictable or ruled by chance. [Subscription required]

New thin plastic film changes colors when you stretch it. Twisting the film changes the spacing between tiny embedded silicon beams, altering the color of light they reflect.

Foiled by science. Student counters fencing advice with sharp experiments.

How computer science was used to reveal Gauguin’s printmaking techniques.

A flowchart of theoretical physics: "I made this yesterday instead of doing research."

Quantum weirdness passes the atomic walk test.

Why does time only run forwards?

Symmetry, A Dance and Opera Film Recorded Inside the CERN Large Hadron Collider:

SYMMETRY - dance & opera film inside CERN from TRUTH.IO on Vimeo.

The man who turned paper into pixels: From blackjack to binary code: how Claude Shannon’s predilection for probability led to the information age. Related: The "Harvard Sentences" Secretly Shaped the Development of Audio Tech.

Chameleons change their colors by rearranging nanocrystals in their skin. Related: Geckos Shed Water Droplets Through a Novel Mechanism That Resembles Popping Popcorn. Also: Snail Shells Are Inspiring Tomorrow's Toughest Materials.

Slime mold builds an ancient road network. "A paper entitled 'Slime Mould Imitates Development of Roman Roads in the Balkans' has just been published in the Journal of Archaeological Science: Reports. The unique heuristic abilities of the slime mould, Plasmodium polycephalum, inspired the scientists to apply the method for the first time in archaeology."

SLAC particle accelerator facility finds new ways to be cutting edge. As particle physics has shifted to CERN, the facility keeps humming along.

Nine Historical Mysteries Solved By Astronomy. "Astrophysicist and forensic astronomer Donald W. Olson and his team at Texas State University use their astronomical tools to solve all manner of mystery. You can read about more of their investigations, and get more details on each of these mysteries, in Olson's book Celestial Sleuth."

Superluminal sweeps and photonics booms: If you sweep a laser pointer across the moon, will the spot move faster than the speed of light?

Monster Flare Explodes From the Sun With Energy of Millions of H-Bombs.

Scientists find rare dwarf satellite galaxy candidates that could present them with more opportunities to search for signatures of dark matter.

Scientists have found a way to make the strongest spider silk fibers.

The Physics of Chad Orzel's Back Gate. "It’s winter, and as usually happens in winter, I’m having a hard time opening the gate to our back yard. Why? It’s not the snow, it’s physics."

Very cool. The Science of a 3D Printed Piezoelectric Violin, in which, "applied pressure is converted directly into an electric signal. This electric signal is then amplified and converted into sound through a speaker." Related: Why violin-makers adopted the f-shaped hole.

Pianographics--Empirical Musicology, 1895. "When a key is struck the style is deflected in such a way that the height of the deflection is proportional to the force of the pressure; the length of the deflection records the time; and finally the form of the curve gives a detailed account of the manner in which the movement was carried out."

NASA Launched a Quad of Magnetic Field Satellites This Week. "This is a group of four satellites which will fly in tetrahedron formation, measuring the magnetic field around the Earth and looking for occasional "magnetic explosions" called magnetic reconnections."

Joseph Nicéphore Niépce, The French Inventor Who Created the First Photograph. Related: How photography evolved from science to art.

A Program That Simulates the Movement of Fluid in Various Scenarios Using ASCII Characters.

New paper in Nature describes the 'beautiful' science that explains why liquid droplets dance with each other. "The drops won't dance when they are just made up of water; the researchers added a second fluid, making the drops binary or two-compound fluids."

Here's What Happens When You Screw With Isaac Newton: the feud with astronomer John Flamsteed.

A Mathematical Model of Oppression: The Petrie Multiplier. A simplified mathematical model shows why you don’t need an evil majority to have an oppressed minority.

Confessions of a mathematical Olympian: an insider view of film X+Y. "The high pressure world of international maths tournaments is brought to life in the much-anticipated British movie X+Y, which opens this weekend. Here a former contestant reveals the maths, the alcohol and the sexual intrigue of these events and tells us whether the film gets it right."

How to survive an encounter with a black hole.

A Blizzard of New Research Results in Astrobiology.

How Sarah Brightman lost her heart to the International Space Station. The recording star turned astronaut will blast off on a rocket in September to give a concert in space.

Robot vs. Robot: Can a computer forge a painting well enough that it fools the algorithms designed to detect fakes? "there’s no guarantee that the final robot-made product would look authentic to a human. Indeed, in one case, when researchers reverse-engineered images of bikinis and golden retrievers from an algorithm designed to detect the items, it spewed back an unrecognizable mess of static hues. Just because a computer can recognize something doesn't mean it can reproduce that thing. (Humans, for the record, have similar artistic limitations.)" For more on the debate over fractal patterns in the paintings of Jackson Pollock, check out my 2011 blog post on the topic.

Master paper artist Kelli Anderson has a forthcoming title called This Book is a Planetarium that literally converts into a planetarium, as well as a smartphone amplifier, and many other paper contraptions.

The Life of a Bubble: There’s more to making a soap bubble than a breath and a wand. Related: Why Does Some Coffee Get Bubbles on Top? Also: Incredible Bubble Art Created By Taiwan’s ‘Bubble Performance Master’:

Francis Galton and the Dawn of Crowd-Sourcing, 1907: "while no one participant got the correct answer spot-on, every participant together made an almost perfect guess."

Water Into Wine: "A trio of physicists at the University of Leicester, in England, got to wondering if such an act was chemically and physically possible. So they sat down and did the calculations, which are reported in the Journal of Physics Special Topics." Paper (PDF)

Flaccid Mechanics: From Penis-Size Statistics to Penis-Size Physics.

Swirl: A futuristic faucet that turns water streams into complex patterns.

Inventor and hacker Pablos Holman Wants You To Break Your Gadgets, says we should take stuff apart to find new uses for it.

A Plea for a Scientific Worldview from An Honest Liar, on Debunker James Randi. “Physicists are most easily deceived, because they deal in a real world of objects,” and their natural inclination is to take anomalies as discoveries rather than as hoaxes, he noted.

A thought-provoking speech from Anthony Pinn, child preacher turned secular humanist.

Buying into physics with Fiat Physica: String theorist Mark Jackson sets out to augment particle physics funding through crowdfunding.

The teacher who believes math equals love.

For gummy bear chemistry/physics enthusiasts: "Drying gummy beard reduce anti-matter lifetime." Paper (PDF)

Hydrothermal vents on Saturn's moon Enceladus hint at conditions for life.

Dance Meets Motion Capture In This Otherworldly Performance. Per io9: "Artists Maria Takeuchi and Frederico Phillips' Asphyxia is more than an experimental dance film; it's also one of the more creative uses of Xbox One Kinect's motion-data capture capabilities we've seen."

as·phyx·i·a from Maria Takeuchi on Vimeo.