physics

Credit: Allen Lane, publisher A Nottingham professor has turned his passion for physics and science communication into his first book, dedicated to a friend who inspired him. …

Suppose this parallel plate capacitor is connected to a 9-volt battery. A volt is a measure of the electric potential difference. In short, this is the electric potential energy per charge—it’s a measure of how much energy a charge would gain by moving across that potential. So, this 9-volt battery will create a 9-volt change in potential across the plates.But what would happen if you pushed one of the plates so that the distance between them decreases just a little bit? Well, since the capacitor is still connected to the…

In March 2018, researchers launched what looks like a white, cooler-sized fridge to the International Space Station. That heavy box houses a $100 million facility known as the Cold Atom Laboratory, which enables an array of atomic physics experiments to be done at freezing temperatures in the zero-g of space. With those unique conditions, scientists have now produced tiny bubbles of extremely cold gas atoms, putting them on the edge of quantum physics territory.That achievement, only possible in microgravity and at a…

A map of Ukraine, with green and red regions marking pro-West and pro-Russian, but the purple outlined regions are more relevant to the war. Credit: Massimiliano Zanin and Johann H. Martínez When reading news and analyses of the Russian invasion of Ukraine, researchers in Spain perceived many conflicting messages being transmitted. The most notable one is the theory of "two Ukraines" or the existence of ideologically pro-West…

Remember we’re dealing with the photon’s wave function here. Since the bounce doesn’t constitute a measurement, the wave function doesn’t collapse. Instead, it splits in two: Most of the wave function remains in the box, but the small, rapidly oscillating piece near where the mirror was inserted leaves the box and heads toward the detector.Because this superoscillatory piece has been plucked from the rest of the wave function, it is now identical to a photon of much higher energy. When this piece hits the detector, the…

Seismic waves from a big quake are easy to see—think of the classic image of a seismograph, pencil scratching out telltale waves on a rotating paper as the tremor arrives. Even to highly trained eyes, PEGS are just squiggles, indistinguishable from the noise. It’s hard to prove they’re there. In 2017, early identifications of PEGS in Tohoku seismic data received pushback from other seismologists.But over time, researchers have collected more observations from earthquakes around the world. “I’ve managed to convince myself…

Our planet also changes positions. In six months, the Earth will go from one side of the sun to the other. This is a change in distance of almost 300 million kilometers, and it's enough to cause a noticeable apparent position change for some of the nearest stars. In fact, parallax is an important tool for measuring the distance to these stars. (Here are the other ways to measure stellar distances.)So, yes, constellations change—but not that much.Finding Your LongitudeHere’s how to find your longitude with a clock and a…

A recent series of precise measurements of already known, standard particles and processes have threatened to shake up physics.As a physicist working at the Large Hadron Collider (LHC) at <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="<div class=glossaryItemTitle>CERN</div><div class=glossaryItemBody>Established in 1954 and headquartered in Geneva, Switzerland, CERN is a European research organization that operates the Large Hadron Collider, the largest…

Octopuses are doomed to be orphans from a very young age. After a female octopus lays her eggs, she stops eating and begins self-mutilating, tearing off her skin and biting off the tips of her tentacles.  By the time a young octopus wriggles out of its egg, its mother is already dead. A few months later, its father will die, too.The short and grim life of the octopus has long fascinated scientists. In 1944, researchers hypothesized that mating was somehow hitting a molecular "self-destruct" button within the sea…

Every time you take a step, space itself glows with a soft warmth.Called the Fulling–Davies–Unruh effect (or sometimes just Unruh effect if you're pushed for time), this eerie glow of radiation emerging from the vacuum is akin to the mysterious Hawking radiation that's thought to surround black holes.  Only in this case, it's the product of acceleration rather than gravity.Can't feel it? There's a good reason for that. You'd need to move at an impossible speed to sense even the weakest of Unruh rays.For now, the effect…