Olympic weightlifting consists of three basic movements performed on a barbell : the snatch, the clean, and the jerk (with the latter two executed in combination). At such an elite level, athletes seek to exploit every possible advantage, including how a barbell bends and recoils in response to loaded weight and applied force—a property known as flexural bending in physics and dubbed the "whip" by Olympic athletes. Scientists are learning more about the underlying mechanisms of the whip, according to a presentation at this week's meeting of the Acoustical Society of America in Philadelphia.

Joshua Langlois, a graduate student at Pennsylvania State University, competes in Strongman competitions as a hobby. He also has friends who compete at the national level in Olympic weight-lifting events. "They told me how they use the whip," Langlois said during a media briefing. "When they dip down, they can feel when the bar flexes back up and use that to accelerate the movement upward to increase the amount they can lift."

Langlois decided to conduct a modal analysis, i.e., how an object moves or vibrates, to quantify the whip and better understand the mechanics, as well as what makes for a good barbell at the elite level. He suspended four 20-kg men's barbells (women use 15-kg barbells)—with 50 kg loaded on each end—from elastic resistance bands so that the bar was essentially floating in space. Then he attached accelerometers at each end of the bar where the vibrational mode patterns occur. Next he tapped set locations across the bar with a small hammer, measuring the acceleration at the end points, which enabled him to map out how the bars moved in response. He compared the vibrations of different barbells, as well as a single barbell loaded with different weights.

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NASA announced Wednesday that it will fly the Artemis III mission in low-Earth orbit and that it continues to target 2027 for this stepping-stone flight that will help land humans on the Moon.

The space agency chose the orbit close to Earth—as opposed to a higher orbit—because it would preserve the final remaining Interim Cryogenic Propulsion Stage for launching the Artemis IV landing mission later this decade. Instead, NASA will use a "spacer" to simulate the mass and overall dimensions of an upper stage but without propulsive capabilities.

The additional information released this week follows a decision made by NASA Administrator Jared Isaacman three months ago to shuffle the agency's Artemis plans in order to accelerate a lunar landing.

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US Space Command is inviting commercial companies to participate in a new series of classified wargames. The first exercise simulated a scenario involving a potential nuclear detonation in orbit.

Gen. Stephen Whiting, the senior officer in charge of Space Command, discussed the new wargame series Tuesday in a discussion hosted by the Mitchell Institute for Aerospace Studies. Space Command is responsible for military activities in space and is separate from the Space Force, which provides the people and equipment to support those operations.

The new wargames, called Apollo Insight, combine military and commercial expertise to respond to simulated threats in space. Space Command plans to conduct four Apollo Insight "tabletop exercises" this year.

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The world’s first dentist was a Neanderthal, according to a recent study.

59,000 years ago in what’s now southwestern Siberia, a Neanderthal had a toothache. It must have been a doozy because they were desperate enough to sit still while someone drilled into the tooth with a sharp stone tool, removing the infected tissue and ultimately relieving the pain.

The process left behind a hole in the tooth that paleoanthropologist Alisa Zubova of the Russian Academy of Sciences and her colleagues recognized, tens of millennia later, as dental work. Archaeologists unearthed the tooth at Chagyrskaya Cave in Russia, and it’s now the oldest known evidence of dentistry—or any direct medical treatment.

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Elon Musk and Sam Altman had very different experiences while testifying at a trial that will determine OpenAI's future , including who runs it, where its research funding comes from, and who can profit from its boldest new technologies.

Musk—who filed the lawsuit alleging that OpenAI under its current leadership has abandoned its nonprofit mission to build AI that benefits humanity and instead serves to enrich people like Altman— spent three grueling days on the stand . At times, he lost his temper, as OpenAI's lawyer, William Savitt, tried to poke holes in Musk's claims that OpenAI executives teamed up with Microsoft to "steal a charity" after duping Musk into donating $38 million in early funding.

On Tuesday, Altman did not face such a grilling from Musk's lawyer, Steven Molo. Instead, Altman appeared jittery at first but steeled his nerves rather quickly. He hopped off the stand after about four hours of rather calmly discussing evidence that he's hoping shows that Musk's claims about OpenAI's for-profit restructuring are disingenuous. Since Musk filed the lawsuit, Altman has insisted that Musk is only after revenge, supposedly stemming from his jealousy that he was not picked as OpenAI's CEO and that his rival company, xAI, now lags behind.

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Hardware driver updates can be a blessing and a curse. When they're good, they can fix bugs, improve performance, and add new capabilities, giving your PC a minor upgrade without requiring any extra effort or investment. When they're bad, they can make a once-reliable PC slower and unstable, handing you a one-way ticket to blue screen town (or whatever color the Windows error screen is these days ).

While gamers and other enthusiasts may be in the habit of downloading and installing new driver updates for their systems, most PC users just let Windows Update handle driver installation and updates. PC manufacturers can submit their own tested and validated versions of drivers for distribution via Windows Update, which (at least in theory) should maximize stability and minimize problems.

But mistakes happen, and sometimes a driver update is distributed that causes more problems than it fixes. Normally when this happens, the company either needs to submit an updated fixed driver to Windows Update, or the user is on the hook for either rolling back the update or finding and downloading a better driver themselves.

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In March, Reuters reported that Amazon was developing a new smartphone . Citing four anonymous “people familiar with the matter,” the publication said that Amazon was exploring using Alexa as an operating system and developing the phone, codenamed Transformer, to push people to use Amazon’s AI and other services. At the time, the sources said that Transformer could still be canceled, and Amazon declined to comment on the report to Ars Technica.

In an interview published on the Financial Times (FT) today, Panos Panay, Amazon's head of devices and services, said building a new phone isn’t Amazon’s goal.

The company already tried selling a smartphone in 2014, but it discontinued the Fire Phone about a year later following poor sales .

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Those with an interest in the concept of AI alignment (i.e., getting AIs to stick to human-authored ethical rules) may remember when Anthropic claimed its Opus 4 model resorted to blackmail to stay online in a theoretical testing scenario last year. Now, Anthropic says it thinks this "misalignment" was primarily the result of training on "internet text that portrays AI as evil and interested in self-preservation."

In a recent technical post on Anthropic's Alignment Science blog (and an accompanying social media thread and public-facing blog post ), Anthropic researchers lay out their attempts to correct for the kind of "unsafe" AI behavior that "the model most likely learned... through science fiction stories, many of which depict an AI that is not as aligned as we would like Claude to be." In the end, the model maker says the best remedy for overriding those "evil AI" stories might be additional training with synthetic stories showing an AI acting ethically.

"The beginning of a dramatic story..."

After a model's initial training on a large corpus of mostly Internet-derived data, Anthropic follows a post-training process intended to nudge the final model toward being "helpful, honest, and harmless" (HHH). In the past, Anthropic said this post-training has leaned on chat-based reinforcement learning with human feedback (RLHF), which it said was "sufficient" for models used mostly for chatting with users.

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For decades, astronomers looking through telescopes like Hubble have been trying to catch a glimpse of the ancient epoch when the Universe's first generation of stars ignited. But the small galaxies that were the building blocks of the cosmos we know today were too faint to spot, even by the most powerful instruments. Now it seems astronomers finally have two things on their side: the Webb Space Telescope and a bit of luck.

In a recent paper in Nature, a team of scientists led by Kimihiko Nakajima, an astronomer at the Kanazawa University, Japan, used the James Webb Space Telescope to observe an ultra-faint galaxy called LAP1-B as it existed roughly 800 million years after the Big Bang. It’s the most chemically primitive galaxy we’ve ever seen.

The magnifying glass

The LAP1-B is 13 billion light-years away from Earth. To observe an object that faint and distant, even the huge, gold-coated beryllium mirrors of JWST were not enough on their own. We spotted it due to a massive cluster of galaxies called the MACS J046, which warps the spacetime between us and the LAP1-B.

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