Day: March 1, 2024

Wouldn’t it be cool if you never had to charge your cell phone? I’m sure that’s what a lot of people were thinking recently, when a company called BetaVolt said it had developed a coin-sized “nuclear battery” that would last for 50 years. Is it for real? Yes it is. Will you be able to buy one of these forever phones anytime soon? Probably not, unfortunately, because—well, physics. Let’s see why.

All batteries do the same thing: They produce an electric current to do some kind of work. But energy isn’t free. If that work is blasting music on your Bluetooth speakers, there has to be something that decreases in energy. In a good old AA, there’s a chemical reaction to produce the current. That chemical reaction doesn’t last forever, so the battery will eventually die.

In a nuclear battery, the power source is a piece of radioactive material, and it will keep on going like the Energizer bunny until the source is no longer radioactive—which isn’t forever, but it’s a heck of a lot longer. These aren’t actually new. The Voyager 1 space probe, launched in 1977, has a nuclear battery. It’s now over 15 billion miles away, and it still has a little juice. That’s pretty good mileage!

The specific type on Voyager is called a radioisotope thermoelectric generator, which is a big name for what is basically a hunk of plutonium in a box. As the plutonium decays, it converts mass to energy, producing heat. If you stick a solid-state device on it, the difference in temperature between the hot and cold metals produces voltage and causes an electric current to flow.

It’s kind of crazy that a temperature difference alone can generate electricity, but you can test this out at home using some copper wire and a paper clip (without the plutonium), by sticking one end in ice water and the other in hot water. This type of power source is great for space probes because it has no moving parts, so it won’t break down, and it lasts for decades.

Now, this new battery announced by BetaVolt uses a different technology called betavoltaic generation. Instead of tapping thermal energy, it captures the ejected electrons, known as beta particles, from a radioactive isotope of nickel to form an electric circuit. It’s made up of several layers of nickel sandwiched between plates of diamond, which serve as a semiconductor. There’s a bunch of cool stuff to go over here, so let’s dive in.

What Happens in Radioactive Decay?

Nickel-63 is an isotope of the stable version of the element, nickel-58. That number is the atomic weight—the total number of protons and neutrons in the nucleus of the atom. Nickel-63 has five extra neutrons, which makes it unstable. Over time, one of those extra neutrons will decay into a proton and produce a new electron. With an extra proton, the atom will now be copper-63, the next element in the periodic table. This nuclear reaction produces energy, shooting the electron out of the atom at high speed.

It’s important to know that the rate of radioactive decay isn’t constant; it depends on the number of atoms of the material present, so the production of electrons declines exponentially over time. In the case of nickel-63, half of the atoms will decay in about 96 years—we say it has a “half-life” of 96 years.

Every six months, the automotive research company JD Power surveys some 5,000 US electric vehicle owners about their experiences driving their battery-powered cars. The latest edition of this survey, out this week, found that EV’s perennial bugbear is still bugbear-ing. In fact, it’s got worse: Drivers say they are even more dissatisfied with the availability of public charging stations than they were a year ago.

In North America, additional charging stations are on their way, thanks in part to a US federally-funded program that seeks to get at least half a million more in the ground by 2030. But in this messy middle period, automakers have come up with another solution: Let Tesla take care of it.

Tesla has the most widespread and dependable charging network in the United States. (In fact, the new survey found that upscale EV drivers are more likely to be happy with public charging—and the majority of them drive Teslas.) It also has a unique charging plug, called the North American Charging Standard. Nearly every global automaker has now pledged to add that plug to its electric vehicles, allowing its drivers to tap into the Tesla charging network.

Ford piloted the “let Tesla take care of it” model last May when it announced it would adopt that plug. Its EVs will come with the connector standard by 2025. And starting today, existing drivers of the Mach-E Mustang and Lightning pick-up truck owners will get access to a hearty chunk of Tesla’s supercharger network, courtesy of free adapters that they can now order off a website Ford just launched. The adapters will be gratis between now and July; after that, they’ll retail for $230, Ford says. The company expects the adapters to begin shipping in late March.

Tesla Saves Best New Chargers For Its Own

Ford regularly surveys its own drivers and “their main pain points have to do with public charging,” Ken Williams, the automaker’s director of charging and energy services, said on a call with reporters this week. The adapter will give Ford drivers access to 15,000 new chargers, bringing the total up to 126,000 chargers and more than 28,000 fast chargers across the US and Canada. (That doesn’t include every charger in the Tesla network; Ford drivers won’t get access to older Tesla charging stations, and Tesla has reserved a select few newer ones for its drivers only.) Drivers will be able to access and pay to charge at the stations through Ford’s app.

On February 22, a fire swept through a 14-story apartment block in the Campanar neighborhood of Valencia, Spain. Ten people died in the blaze. Smartphone footage showed an awning on a seventh-floor balcony catching fire at around 5:30pm CET, before the flames rushed upwards. Within 15 minutes, the entire building was engulfed, aided by 40 mph winds.

The inferno quickly drew comparisons to London’s Grenfell Tower fire, which killed 72 people in 2017. While what drove the blaze in Valencia is unclear, attention immediately turned to the building’s cladding—material added to the outside of high-rise blocks to improve insulation and aesthetics, and which helped the Grenfell fire spread so quickly. Until 2019, Spain, like many nations, permitted flammable materials to be included in cladding on new high-rises. While the law has changed, hundreds if not thousands of existing Spanish buildings are likely encased in non-flame-retardant panels.

The same danger lurks internationally. Many countries still allow highly flammable cladding to be used in construction. Others, despite banning dangerous materials on new buildings, still have older ones encased in layers of materials highly vulnerable to fire. “Valencia will not be the last one,” says Guillermo Rein, professor of fire science at the department of mechanical engineering of Imperial College London. “Not in Spain, nor anywhere else.”

The world’s cladding crisis stems from another. In the 1970s, the oil crisis created a problem for architecture to solve: how to design more energy-efficient buildings in the face of soaring fuel prices. Facades were to be redrawn from the ground up. “They were once only made of stone, brick, or concrete and very simple,” says Rein. “But they play a complex role: the interface between inside and outside; sunlight and darkness; warmth and cold; noise and quiet.”

Integral to the design of new facades were synthetic polymers: materials made of chains of repeating subunits, and which are the main ingredient of household plastics. Versatile, lightweight, strong, and inexpensive, polymers became architects’ wonder material, offering improved insulation and faster construction time than concrete mixed on-site. It solved all their biggest problems, says Rein, except one. “All polymers are flammable.”

For more than five decades, a polymer core has typically been sandwiched between ultra-thin panels made from aluminum composite material (ACM) on the facade of modern high-rises. “Architects love what you can do with aluminum. You can curve the facade, add a shine, and make it visually appealing,” says Rein. “And it hides the ugly insulation beneath it.”

While commercial ACM manufacturers have always fire-tested these materials, before Grenfell, results would often be obfuscated from the building sector, says Rein. A typical test would see a blowtorch applied to the front of the ACM—the metal would sustain the flame long enough for the manufacturer to claim it was “fire resistant.” However, flammability comes from the polymer, not aluminum. And these tests didn’t necessarily engulf the material the way an actual fire would.

“If you turn the ACM 90 degrees, and attack the edge with the polymer exposed, the aluminum peels off in 20 seconds and a ball of fire rips, creating black smoke and big flames,” Rein says.

Scientists have determined a way to measure gravity on microscopic levels, perhaps bringing them closer to forming a theory of "quantum gravity" and to solving some major cosmic mysteries.

Quantum physics offers scientists the best description of the universe on tiny scales smaller than atoms. Albert Einstein’s theory of general relativity, on the other hand, brings about the best description of physics on huge, cosmic scales. Yet, something is frustratingly missing even after 100 years of both theories passing a wealth of experimental verification.

As robust and accurate as the two theories developed at the turn of the 20th century have become, they have refuse to unite. 

One of the primary reasons for this dilemma is that, while three of the universe’s four fundamental forces — electromagnetism, the strong nuclear force and the weak nuclear force — have quantum descriptions, there is no quantum theory of the fourth: Gravity. 

Now, however, an international team has made headway in addressing this imbalance by successfully detecting a weak gravitational pull on a tiny particle using a new technique. The researchers believe this could be the first tentative step on a path that leads to a theory of "quantum gravity."

"For a century, scientists have tried and failed to understand how gravity and quantum mechanics work together," Tim Fuchs, team member and a scientist at the University of Southampton, said in a statement. "By understanding quantum gravity, we could solve some of the mysteries of our universe — like how it began, what happens inside black holes, or uniting all forces into one big theory."

Related: ‘Wavy space-time’ may explain why gravity won’t play by quantum rules

Gravity gets the ‘spooky’ treatment

It is maybe fitting that general relativity and quantum physics don’t get along; after all, Einstein was never comfortable with quantum physics. This is because while quantum physics has many counterintuitive aspects, he found one in particular very troubling.

It was the notion of entanglement. At risk of simplification, entanglement has to do with coordinating particles in such a way that changing the properties of one particle instantly alters the properties of an entangled partner particle, even if the partner is located on the opposite side of the universe. Einstein called this "spooky action at a distance" as it challenged the concept of local realism.

Local realism is the idea that objects always have defined properties and that interactions between those objects are limited by distance and the speed of light, a universal speed limit introduced by Einstein as the foundation of special relativity. Special relativity is, in fact, the theory that led to the formulation of general relativity in the first place. Yet, despite Einstein’s protestations, scientists have indeed proven that entanglement and other counterintuitive aspects of quantum physics are truly factors of reality at sub-atomic scales.

Such proof has been achieved with a multitude of pioneering experiments. Fuchs and colleagues, for instance, are following in the footsteps of physicists such as Alain Aspect, John Clauser and Anton Zeilinger, who won the 2022 Nobel Prize in Physics for experimentally verifying the non-local nature of entanglement.

In their new quantum experiment, the researchers, including scientists from Southampton University, Leiden University and the Institute for Photonics and Nanotechnologies, used superconducting magnetic "traps" to measure the weak gravitational pull on the smallest mass anyone has ever attempted to investigate in this way.

The tiny particle was levitated in the superconducting trap at temperatures of around -459.4 degrees Fahrenheit (-273 degrees Celsius), which is just a few hundredths of a degree above absolute zero, the hypothetical temperature at which all atomic movement would cease. This frigid temperature was needed to limit the vibrations of the particles to the very minimum. The team ultimately measured a gravitational pull of 30 "attoNewtons" on the particle.

AttoNewtons represent a measure of force; to give you an idea of how tiny the gravitational force on the studied particles was, one Newton is defined as the force needed to provide a mass of one kilogram with an acceleration of one meter per second per second. And 30 attoNewtons is equivalent to 0.00000000000000003 Newtons!

"Now we have successfully measured gravitational signals at the smallest mass ever recorded, it means we are one step closer to finally realizing how it works in tandem," Fuchs said. "From here, we will start scaling the source down using this technique until we reach the quantum world on both sides."

Team member and University of Southampton scientist Hendrik Ulbricht said this experiment paves the way for tests with even smaller masses, as well as the measurement of even smaller gravitational forces. 

"We are pushing the boundaries of science that could lead to new discoveries about gravity and the quantum world. Our new technique that uses extremely cold temperatures and devices to isolate the vibration of the particle will likely prove the way forward for measuring quantum gravity," he concluded. "Unravelling these mysteries will help us unlock more secrets about the universe’s very fabric, from the tiniest particles to the grandest cosmic structures."

The team’s research was published on Friday (Feb. 23) in the journal Science Advances.

A new climate intervention strategy aims to decrease the amount of water vapor in the stratosphere by injecting it with ice-forming nuclei. The idea is that, by reducing the water content, more heat in the form of infrared radiation would leak out into space.

Scientists described the strategy a study published Wednesday in Science Advances. “It’s not a very complicated idea,” Joshua Schwarz, a researcher at National Oceanic and Atmospheric Administration’s Earth System Research Laboratory and lead study author, told Gizmodo. “But this idea… it’s not a silver bullet, it’s not the magic solution that nobody knows about. It’s just one alternative that will do a little something in the right direction.”

Water vapor acts as a greenhouse gas in Earth’s atmosphere, absorbing radiation from the Sun and then emitting it to the surface of our planet. The scientists behind the new study want to target a small amount of the water vapor found in the stratosphere, the second layer of Earth’s atmosphere, by adding ice-nucleating particles. With water vapor condensing to ice, there would be less trapped heat. Removing around 3% of the water vapor would have a global effect, according to the study.

Using observations from NASA’s Airborne Tropical TRopopause EXperiment (ATTREX), a research aircraft that tracked the transport of water vapor into the upper atmosphere, the team created a model to examine the amount of particles needed to pull off stratospheric dehydration and their predicted trajectories. The models suggested that the idea can work to help mitigate the effects of global warming, but a lot of technical challenges still lie ahead in terms of implementing the strategy.

“We have confidence that it would be a win… that it wouldn’t do anything bad and we know exactly how to do it,” Schwarz said. “We didn’t find anything that said, this is impossible, give up. Instead, we only learned that there’s still more to know.”

The stratosphere extends from 4 to 12 miles (6 to 20 km) above Earth’s surface to around 31 miles (50 km) up. There are aircraft capable of reaching those heights, but the idea still needs the development of an engineering capability to inject the nuclei into the stratosphere. And much more work would need to be done to identify the potential risks and unintended effects.

“If we had one magic way to [address climate change] I wouldn’t say, oh we shouldn’t use it,” Schwarz said. “At this point, my feeling is we need more ideas and to explore the implications of the approaches we decided to take…it might be easier to get a mixture of options that’s better for the planet and humanity than just one approach.”