A New Type of Magnetism

ALL THE MAGNETS you have ever interacted with, such as the tchotchkes stuck to your refrigerator door, are magnetic for the same reason. But what if there were another, stranger way to make a material magnetic?

In 1966, the Japanese physicist Yosuke Nagaoka conceived of a type of magnetism produced by a seemingly unnatural dance of electrons within a hypothetical material. Now, a team of physicists has spotted a version of Nagaoka’s predictions playing out within an engineered material only six atoms thick.   READ MORE...

Robots Do Housework

As someone who quite enjoys the Zen of tidying up, I was only too happy to grab a dustpan and brush and sweep up some beans spilled on a tabletop while visiting the Toyota Research Lab in Cambridge, Massachusetts last year. The chore was more challenging than usual because I had to do it using a teleoperated pair of robotic arms with two-fingered pincers for hands.


As I sat before the table, using a pair of controllers like bike handles with extra buttons and levers, I could feel the sensation of grabbing solid items, and also sense their heft as I lifted them, but it still took some getting used to.


After several minutes tidying, I continued my tour of the lab and forgot about my brief stint as a teacher of robots. A few days later, Toyota sent me a video of the robot I’d operated sweeping up a similar mess on its own, using what it had learned from my demonstrations combined with a few more demos and several more hours of practice sweeping inside a simulated world.  READ MORE...

FedEx's New Robot

FEDEX UNVEILED A two-armed robot called DexR this week that’s designed to automate one of the trickiest tasks facing the company’s human employees—loading a truck with packages.


The new robot aims to use artificial intelligence to stack rows of differently sized boxes inside a delivery truck as efficiently as possible, attempting to maximize how many will fit.


That task is far from easy for a machine. “Packages come in different sizes, shapes, weights, and packaging materials, and they come randomized,” says Rebecca Yeung, vice president of operations and advanced technology at FedEx. 

The robot uses cameras and lidar sensors to perceive the packages and must then plan how to configure the available boxes to make a neat wall, place them snugly without crushing anything, and react appropriately if any packages slip.


“A few years ago, AI was not at a stage where it was smart enough to handle this kind of complex decision-making,” Yeung says. DexR is currently in testing, ahead of a wider rollout at FedEx at some point in the future.


While generative AI tools like ChatGPT have created a sense in many industries that AI technology is ready to take on just about anything, handling objects in the messy, unpredictable real world still poses formidable challenges for algorithms. 

Most industrial robots are designed to carry out highly repetitive jobs with extreme precision, but no variation. 
READ MORE...

Painting with Cosmic Neutrinos

THE ORIGINAL VERSION of this story appeared in Quanta Magazine.

Of the 100 trillion neutrinos that pass through you every second, most come from the sun or Earth’s atmosphere. But a smattering of the particles—those moving much faster than the rest—traveled here from powerful sources farther away. For decades, astrophysicists have sought the origin of these “cosmic” neutrinos. Now, the IceCube Neutrino Observatory has finally collected enough of them to reveal telltale patterns in where they’re coming from.

In a paper published in June in Science, the team revealed the first map of the Milky Way in neutrinos. (Usually our galaxy is mapped out with photons, particles of light.) The new map shows a diffuse haze of cosmic neutrinos emanating from throughout the Milky Way, but strangely, no individual sources stand out. “It’s a mystery,” said Francis Halzen, who leads IceCube.

The results follow an IceCube study from last fall, also in Science, that was the first to connect cosmic neutrinos to an individual source. It showed that a large chunk of the cosmic neutrinos detected so far by the observatory have come from the heart of an “active” galaxy called NGC 1068. In the galaxy’s glowing core, matter spirals into a central supermassive black hole, somehow making cosmic neutrinos in the process.

“It’s really gratifying,” said Kate Scholberg, a neutrino physicist at Duke University who wasn’t involved in the research. “They’ve actually identified a galaxy. This is the kind of thing the entire neutrino astronomy community has been trying to do for forever.”

Pinpointing cosmic neutrino sources opens up the possibility of using the particles as a new probe of fundamental physics. Researchers have shown that the neutrinos can be used to open cracks in the reigning standard model of particle physics and even test quantum descriptions of gravity.

Yet identifying the origin of at least some cosmic neutrinos is only a first step. Little is known about how the activity around some supermassive black holes generates these particles, and so far the evidence points to multiple processes or circumstances.  READ MORE...

How Earth's Atmosphere Changed

A DENSE RAINFOREST or other verdant terrestrial vegetation may be what first comes to mind at the mention of photosynthesis. Yet the clouds of phytoplankton that fill the oceans are the major drivers of that process in nature. 

The plantlike single-celled aquatic microbes generate more than 50 percent of the oxygen in the atmosphere, and they absorb nearly half of the carbon dioxide, converting it into the glucose, fats, proteins and other organic molecules that nourish the food web of the oceans.

A recently published study in Current Biology finally pins down the source of this unparalleled photosynthetic efficiency, which has long baffled scientists. The new research found that some phytoplankton are equipped with an extra internal membrane that carries a “proton pump” enzyme that supercharges their ability to convert carbon dioxide into other substances. 

The enhancements due to this one protein modification seem to contribute to the production of nearly 12 percent of the oxygen in the air and as much as 25 percent of all the carbon “fixed” (locked into organic compounds) in the ocean.

Surprisingly, that photosynthetic innovation seems to have evolved by chance from a membrane protein that was originally used for digestion in the ancestor of the phytoplankton. 

In addition to explaining the cells’ prowess at photosynthesis, the new work helps to confirm the theory that those phytoplankton arose through a symbiotic alliance between a protozoan and a resilient red alga.

“I find it staggering that a proton enzyme that we have known for so many decades is responsible for maintaining such a crucial phenomenon on Earth,” said Dennis Brown, a cell biologist at Harvard Medical School who studies the functions of membrane proteins and was not involved in the study.

Researchers knew that certain classes of phytoplankton—diatoms, dinoflagellates, and coccolithophores—stand out for their exceptional photosynthetic abilities. 

Those cells are extremely proficient at absorbing carbon dioxide from their environment and directing it to their chloroplasts for photosynthesis, but the details of why they are so good at it haven’t been very clear. A feature unique to those three groups of phytoplankton, however, is that they have an extra membrane around their chloroplasts.  READ MORE...

Pausing Chat GPT

AN open letter signed by hundreds of prominent artificial intelligence experts, tech entrepreneurs, and scientists calls for a pause on the development and testing of AI technologies more powerful than OpenAI’s language model GPT-4 so that the risks it may pose can be properly studied.

It warns that language models like GPT-4 can already compete with humans at a growing range of tasks and could be used to automate jobs and spread misinformation. The letter also raises the distant prospect of AI systems that could replace humans and remake civilization.

“We call on all AI labs to immediately pause for at least 6 months the training of AI systems more powerful than GPT-4 (including the currently-being-trained GPT-5),” states the letter, whose signatories include Yoshua Bengio, a professor at the University of Montreal considered a pioneer of modern AI, historian Yuval Noah Harari, Skype cofounder Jaan Tallinn, and Twitter CEO Elon Musk.

The letter, which was written by the Future of Life Institute, an organization focused on technological risks to humanity, adds that the pause should be “public and verifiable,” and should involve all those working on advanced AI models like GPT-4. It does not suggest how a halt on development could be verified, but adds that “if such a pause cannot be enacted quickly, governments should step in and institute a moratorium,” something that seems unlikely to happen within six months.

Microsoft and Google did not respond to requests for comment on the letter. The signatories seemingly include people from numerous tech companies that are building advanced language models, including Microsoft and Google. Hannah Wong, a spokesperson for OpenAI, says the company spent more than six months working on the safety and alignment of GPT-4 after training the model. She adds that OpenAI is not currently training GPT-5.  READ MORE...

A Future Without White People

PHOTOGRAPH: LEONARDO CENDAMO/GETTY IMAGES

WHITENESS IS A seduction. Whiteness is also an illusion. These are the twin motifs on which Pakistani writer Mohsin Hamid props up The Last White Man, his new novel about race metamorphosis and human morality. 

Anchored in the bare and elegiac prose Hamid has made his trademark style, the book springboards from a single unexplained incident. Anders, a white man, awakens one morning to a new reality: his skin has “turned a deep and undeniable brown.”

The transformation, of which Anders’ is the first—but not the only, and certainly not the last—elicits worthy exploration. What if whiteness were suddenly gone? Would the social order of life come undone? Would anything change? Where Hamid lands doesn’t exactly persuade.

The sequence of events that follows plays into an ancient fear, that of The Other. (One’s need to estrange, Toni Morrison has said, is “a desperate attempt to confirm one’s own self as normal.”) For Anders, confusion bubbles. Panic swells. 

Initially, he flirts with thoughts of violence after realizing the transformation is irreversible. “He wanted to kill the colored man who confronted him here in his home,” Hamid writes, “to extinguish the life animating this other’s body, to leave nothing standing but himself, as he was before.”

It’s understandable why those who benefit from a particular standing would do anything to preserve it. The conscious seduction of power, of understanding the privileges from which one benefits and the life it affords, is, in part, about the necessity of control. I’d probably be upset and a little sad if I lost all of that, too.  READ MORE...

Moon's Permanent Shadows

Original story reprinted with permission from Quanta Magazine, an editorially independent publication of the Simons Foundation whose mission is to enhance public understanding of science by covering research develop­ments and trends in mathe­matics and the physical and life sciences.



ON OCTOBER 9, 2009, a 2-ton rocket smashed into the moon traveling at 9,000 kilometers per hour. As it exploded in a shower of dust and heated the lunar surface to hundreds of degrees Celsius, the jet-black crater into which it plummeted, called Cabeus, briefly filled with light for the first time in billions of years.

The crash was no accident. NASA’s Lunar Crater Observation and Sensing Satellite (LCROSS) mission aimed to see what would be kicked up from the lunar shadows by the impact. A spacecraft trailing the rocket flew through the dust plume to sample it, while NASA’s Lunar Reconnaissance Orbiter observed from afar. The results of the experiment were astonishing: Scientists detected 155 kilograms of water vapor mixed into the dust plume. They had, for the first time, found water on the moon. “It was absolutely definitive,” said Anthony Colaprete of NASA’s Ames Research Center, the principal investigator of LCROSS.

The moon isn’t an obvious reservoir of water. “It’s really weird when you stop to think about it,” said Mark Robinson, a planetary scientist at Arizona State University. Its lack of atmosphere and extreme temperatures should cause any water to almost instantly evaporate. Yet about 25 years ago, spacecraft began to detect signatures of hydrogen around the moon’s poles, hinting that water might be trapped there as ice. LCROSS proved this theory. Scientists now think there’s not just a bit of water ice on the moon; there are 6 trillion kilograms of it.  READ MORE...

Ending Civilization

TO A PHOTON, the sun is like a crowded nightclub. It’s 27 million degrees inside and packed with excited bodies—helium atoms fusing, nuclei colliding, positrons sneaking off with neutrinos. 

When the photon heads for the exit, the journey there will take, on average, 100,000 years. (There’s no quick way to jostle past 10 septillion dancers, even if you do move at the speed of light.) 

Once at the surface, the photon might set off solo into the night. Or, if it emerges in the wrong place at the wrong time, it might find itself stuck inside a coronal mass ejection, a mob of charged particles with the power to upend civilizations.

The cause of the ruckus is the sun’s magnetic field. Generated by the churning of particles in the core, it originates as a series of orderly north-to-south lines. But different latitudes on the molten star rotate at different rates—36 days at the poles, and only 25 days at the equator. 

Very quickly, those lines stretch and tangle, forming magnetic knots that can puncture the surface and trap matter beneath them. From afar, the resulting patches appear dark. They’re known as sunspots. Typically, the trapped matter cools, condenses into plasma clouds, and falls back to the surface in a fiery coronal rain. 

Sometimes, though, the knots untangle spontaneously, violently. The sunspot turns into the muzzle of a gun: Photons flare in every direction, and a slug of magnetized plasma fires outward like a bullet.  READ MORE...