Physics Buzz

Why does a change in the seasons always seem to creep up on us? Winter has a way of seeming like it'll never end, like every day closer to springtime brings only another minute of sunlight—and then, nearly all at once, you're enjoying a sunset at 7 PM in nothing more than a light jacket.

Quantum is one of those words that's a godsend if you're a lazy science-fiction author in need of a plot device, or someone trying to scam people into buying your  crappy, overpriced jewelry . It evokes scientific knowledge and mystery all at once; it lets things be in two places at the same time, or jump to alternate universes.

Last week, Joe from Massachusetts wrote in to ask: Life is possible through the transfer of the sun's energy, through photosynthesis, and animals eating and us eating them. Is it possible to measure how much energy a person receives from the sun in order to live an average life, say 85 years being the average? Tall order, yes?

At the intersection of physics and philosophy, there's a question that's weighed on the minds of great thinkers for centuries: Is there truly such a thing as free will? When we make a choice, are we fundamentally any different than a calculator "choosing" which segments of its display to light up when the = button is pressed?

Allow me to take a moment to introduce myself and tell you a bit about my background. I am the new APS science writing intern. Currently, I hold four bachelor's degrees and am working on a master's.  My first bachelor's was in English from Florida Gulf Coast University. Last May (2017) I graduated from Florida State University with three Bachelor of Science degrees in astrophysics, meteorology, and biomathematics. This past fall I started my master's degree in space studies through the University of North Dakota.

Chemistry, in one form or another, has been practiced for thousands of years—but for most of that time, it was more akin to wizardry than the hard science we know today. The alchemists of old wielded a strange and marvelous power, to mix two substances and create something entirely new, something that couldn't be separated back into its original parts...except by more alchemy. Through trial and error, mixing up ingredients that seemed like they might be powerful—smelly sulfur, or metals like mercury—we slowly gathered enough pieces of the puzzle that clever people began to see the outlines of the whole shape: the Periodic Table.

This week, Andrew from Quincy, WA wrote in to ask: I'm writing a book, and trying to think of small-scale power sources—I want the ideas to be at least theoretically possible. Is it theoretically possible to slightly compress an atom to cause the electrons to vibrate? Also could that cause heat as well, and could you harness either of those to produce electricity?

Many physicists have a moment they can point to as the moment they decided to study physics. Often it is a teacher, or an experiment, or a demo show that made them think physics was the most interesting and fascinating subject. Others might be inspired to follow the path of a favorite author or television character. For me, Dana Scully was that character. I grew up watching the X-Files and for the first time I saw someone like me (well, not exactly like me, I'll never be that well put together or able to walk in heels) as a scientist. For many from my generation she was the first time we saw a female lead on TV that was not a sidekick and was treated as a full and engaging character. She also happened to be a physicist. This made me feel like I could do that, too.

Once in a rare while, the moon turns red—because the sky is blue. That might sound like nonsense, but it's the simplest accurate way to explain what happened early this morning, when the moon disappeared from view before returning with an eerie, rusty cast to it.

Last week, reader James from Melbourne wrote in: I was having a discussion with a colleague about what would hit the ground first if it fell from a plane (let’s say 15,000 ft). An elephant (let’s say African) or a standard brick. Curious to know your thoughts. Thanks! 

With the first parts of this series (read part I , part II , and part III ), we've built up the idea that the electric charge of a particle is very closely analogous to the angular momentum of an eddy in a fluid. Alike-spinning whirlpools repel, while opposite-spinning ones attract and, when they meet, annihilate one another—with the energy they contained radiating away as waves , just like matter and antimatter. But the surface of a pond is only two-dimensional, so to find out just how far this analogy goes, we're going to have to stretch our imaginations into higher spaces. Let's dive in.

Seeing bare tree branches silhouetted against a sunset sky is one of the best things about winter. Bereft of leaves, the trees reveal their intricate skeletons—almost fractal, reminiscent of neurons, or the network of blood vessels that perfuse the body. These complex patterns of growth and branching are produced by an invisible algorithm—less a blueprint than a computer program—encoded in the tree’s DNA, optimized over millions of years of evolution. Taking data on sunlight, airflow, and proximity to other branches, the tree regulates the expression of growth hormones to ensure that it’s making the most of its space. With all the care that goes into their creation, it’s no surprise that the patterns they produce come out so marvelously complex.

When magnetic fields clash, they can rapidly unleash powerful explosions. Now scientists may have solved the decades-old mystery behind how these outbursts can happen so quickly. The findings could one day help explain the origins of the most powerful explosions in the universe and point to ways to build stable nuclear fusion reactors.

This post is part of a series, (read Part I and Part II ) introducing a heuristic method for thinking about spacetime and charge that I like to call "the pond". Electromagnetic waves are often described as being similar to waves on water, and it turns out the analogy can be extended—if photons are waves, charged particles are like whirlpools: excitations with a little bit of angular momentum to them which allows them to persist.

"A good idea is useless if does not convince others. An idea that is only convincing to oneself is dead." These wise words represent a hard-learned lesson for Dr. Ramon Ferrer-i-Cancho, a scientist in the Complexity and Quantitative Linguistics lab at the Universitat Politècnica de Catalunya. Ferrer-i-Cancho has spent nearly two decades fleshing out a mathematical theory to describe the natural elegance of languages, fighting skepticism and intellectual inertia every step of the way. Now, with a publication in the American Physical Society's journal  Physical Review E , he hopes to both refute and convert his dissenters once and for all.

In our last post , we introduced the pond —the surface of a body of water serving as an intriguing analogy for spacetime—with waves as a transient expression of energy, much like photons or gravitational waves, and eddies representing charged particles like protons and electrons. We found that two whirlpools spinning the same direction will repel one another, much like two particles of the same charge—but what about ones spinning opposite directions?

When physicists try to describe spacetime and its interactions with matter, the analogy we invariably seem to fall back on involves an elastic sheet, with bowling balls creating curvature on it and marbles orbiting those bowling balls like planets around a sun.

This week, Amandeep from Toronto wrote in to ask: According to Einstein’s theory of relativity time slows down as speed of the object increases. What is the rate of change of time? E.g. if time was being measured by a simple clock, can we see the hands of the clock slowing down at a certain rate as a result of increase in speed? Thanks, Amandeep

Chirps, short bursts of (often annoying) high-pitched sounds, are generally a way of conveying information. Birds chirp to warn their feathered friends of impending danger. Male crickets chirp to announce their intentions to females. Smoke alarms chirp to keep you awake all night until you finally get up and change that low battery.

Knowing more about how a metal tube crumples might improve the design of everything from beer cans to space rockets. Now scientists find that poking such cylinders in the side could help predict when they might buckle from weights or pressure from above.