Physics Week in Review: December 2, 2017

This week's physics highlights: does hot water really freeze faster than cold, and could cold water heat up faster than hot; scientists reverse the arrow of time; and a new quantum simulator holds experimental promise.

When Cold Warms Faster Than Hot. Does hot water really freeze faster than cold? My latest article for Physics World describes what could be a new theoretical understanding for the so-called Mpemba effect - and why it predicts that cold water could even heat up faster than warm water.

And speaking of weird counter-intuitive physics, Scientists Reversed the Arrow of Time in a New Quantum Experiment. It "shows that, unlike heat dissipating from your coffee cup on a cold day, quantum particles can transfer heat energy away from cold particles and toward hotter ones, a reversal of the second law." Related: Think there's no time like the present? Modern physics begs to differ.

Dice Become Ordered When Stirred, Not Shaken. A jumble of thousands of cubic dice, agitated by an oscillating rotation, can rapidly become completely ordered, a result that is hard to produce with more conventional shaking.

Gravity Signals Could Speedily Warn of Big Quakes and Save Lives. The trick lies in capturing the weak gravitational shifts in the ground.

Secret Link Uncovered Between Pure Math and Physics. "In mathematics, the simplest things are often the hardest to understand. They're simple like a sheer wall, without crannies or ledges or obvious properties you can grab ahold of."

Two Incredible New Quantum Machines Have Made Actual Science Discoveries. Best-yet quantum simulator with 53 qubits could really be useful.

MIT scientists created a new method to mix oil and water.

Particle Accelerator Peers Inside Ancient Girl Mummy.

Physicists show that thunderstorms trigger nuclear reactions in the atmosphere. A streak of lightning in the skies over Japan has generated positrons - the antimatter equivalents of electrons - and radioactive carbon-14.

Dark Matter Is Not Dead. "scientists are taking issue with a hyped-up new paper that claims it can eliminate the need for dark matter or dark energy in our Universe."

A physicist explains the science of hyperspace-and why Star Wars isn't entirely fiction.

LIDAR Just Got Way Better-But It's Still Too Expensive for Your Car. See also my 2012 blog post about LIDAR. Related: See the Strange, Beautiful Landscapes Revealed by Lasers (LIDAR). Technology unearths a world hidden beneath the lush forests of the Pacific Northwest. [Image: A landslide covered with vegetation near Deming, Washington is revealed with LIDAR. Courtesy of Washington Geological Survey]

A Physicist's Physicist Ponders the Nature of Reality. Edward Witten reflects on the meaning of dualities in physics and math, emergent space-time, and the pursuit of a complete description of nature.

LHC data: How it's made. protons become new particles, which become energy and light, which become data.

1965: Rabbits versus relativity. Rabbits also seem to have an uncanny ability to land on their feet.

New NASA visualization uses data from NASA satellites combined with a model of physics and meteorology to track recent hurricanes and associated aerosols: dust, smoke, sea salt.

Why Chemical Rockets and Interstellar Travel Don't Mix. A toothpick proves that nobody's getting to the stars very quickly using conventional rocketry.

54 years after Fi(C)licette's flight, the first (and only) cat in space is finally getting a memorial.

Would you go to grad school to learn how to mine in space? The Colorado School of Mines Wants to Launch the First-Ever Space Mining Program.

What Is Multispectral Imaging And How Is It Changing Archaeology And Digital Humanities Today?

First Nuclear Chain Reaction Changed the World 75 Years Ago Today. Related: The Atomic Age: Far More Than Explosions and Electricity. Also: The atomic age began with a secret test 75 years ago. Meet the last surviving witness.

Five Ways to Fix Statistics. As debate rumbles on about how and how much poor statistics is to blame for poor reproducibility, Nature asked influential statisticians to recommend one change to improve science. The common theme? The problem is not our maths, but ourselves.

How Do You Charge Your DC Phone With an AC Source? This simple demo shows you how.

This Is The Science Behind Super Mario Odyssey's Weird Food Volcano.

A Flat Earther's Steamy Attempt at Proof. Plus, why some flat earth enthusiasts claim forests aren't real. Seriously. Flat Earth Researcher Told He Can't Blast Himself Into the Sky at 500 MPH on Public Lands. Related: Hey, Flat Earther, no need to launch a rocket to test your ideas. You don't need to build a rocket to prove the Earth isn't flat - here's the simple science. Also: Understanding the (Really Ridiculous) Core Tenets of the Flat Earth Hypothesis.

Watch colorful iron shavings pulse to music in real time. Roman De Giuli created Matereality, his latest in series of abstract films of chemical and physical reactions shot in extreme closeup.

Pioneering Physicist Enrico Fermi on the "Utility" of Science, the Aim of Knowledge, and Our Ultimate Responsibility to Nature.

The Physics Behind the Strange Interstellar Asteroid 'Oumuamua. Related: Rebecca Boyle on the interstellar interloper nicknamed 'Oumuamua, Arthur C. Clarke, and why science fiction can be a window into reality.

When cream hits coffee, the math is magical. "Cream and coffee obviously mix, but when they first come into contact, the cream actually tends to hover briefly on the hot surface-and researchers just figured out exactly how it works."

Black holes are simpler than forests and science has its limits.

The Koch Snowflake: A look at the most festive fractal.

When a droplet falls on a pool, we expect it to coalesce, but millimeter-sized droplets stick around for far longer than it seems like they should.

"One of the reasons I became a chemical physicist is I liked working at that interface with the chemistry and physics, not so much about the distinction." Scott Bembenek, author of The Cosmic Machine was a guest on Cara Santa Maria's Talk Nerdy podcast.

Metaphysics of metamorphosis: The swarming, ever-changing character of the living world challenges our deepest assumptions about the nature of reality.

Fractions: Where It All Goes Wrong. Why to Americans have such trouble with fractions-and what can be done?

The Best Way to Test Students? Make Them Explain It On Video. "You will be surprised how quickly a short video conveys just what students know-or don't know-about the subject. I can tell how well they understand a concept simply by looking at the problem they choose to solve."

Liquid Sand Hot Tub: Making a giant fluidized bed of sand. "After creating 25 failed homemade versions of this experiment, former NASA JPL engineer Mark Rober succeeds in making a giant fluidized bed of sand inside an old hot tub."