Ars Technica
Mathematicians finally solved Feynman’s “reverse sprinkler” problem
A typical lawn sprinkler features various nozzles arranged at angles on a rotating wheel; when water is pumped in, they release jets that cause the wheel to rotate. But what would happen if the water were sucked into the sprinkler instead? In which direction would the wheel turn then, or would it even turn at all? That's the essence of the "reverse sprinkler" problem that physicists like Richard Feynman, among others, have grappled with since the 1940s. Now, applied mathematicians at New York University think they've cracked the conundrum, per a recent paper published in the journal Physical Review Letters—and the answer challenges conventional wisdom on the matter.
“Our study solves the problem by combining precision lab experiments with mathematical modeling that explains how a reverse sprinkler operates,” said co-author Leif Ristroph of NYU’s Courant Institute. “We found that the reverse sprinkler spins in the ‘reverse’ or opposite direction when taking in water as it does when ejecting it, and the cause is subtle and surprising.”
Ristroph's lab frequently addresses these kinds of colorful real-world puzzles. For instance, back in 2018, Ristroph and colleagues fine-tuned the recipe for the perfect bubble based on experiments with soapy thin films. (You want a circular wand with a 1.5-inch perimeter, and you should gently blow at a consistent 6.9 cm/s.) In 2021, the Ristroph lab looked into the formation processes underlying so-called "stone forests" common in certain regions of China and Madagascar. These pointed rock formations, like the famed Stone Forest in China's Yunnan Province, are the result of solids dissolving into liquids in the presence of gravity, which produces natural convective flows.
Fans preserve and emulate Sega’s extremely rare ‘80s “AI computer”
Enlarge / "Expanding the Possibilities.....with Artificial Intelligence" (credit: SMS Power)
Even massive Sega fans would be forgiven for not being too familiar with the Sega AI Computer. After all, the usually obsessive documentation over at Sega Retro includes only the barest stub of an information page for the quixotic, education-focused 1986 hardware.
Thankfully, the folks at the self-described "Sega 8-bit preservation and fanaticism" site SMS Power have been able to go a little deeper. The site's recently posted deep dive on the Sega AI Computer includes an incredible amount of well-documented information on this historical oddity, including ROMs for dozens of previously unpreserved pieces of software that can now be partially run on MAME.
An ’80s vision of AI’s futureYouTube Premium announces 100 million subscribers
Enlarge (credit: Jericho / Ron Amadeo)
Hot on the heels of Google's "One" subscription plan obtaining 100 million users, YouTube is also hitting that big milestone, with 100 million people paying for Premium and YouTube Music. YouTube's subscription data didn't make it into the earnings call three days ago.
It's hard to know what exactly is driving YouTube's subscriptions. Premium gets you both ad-free YouTube videos and YouTube Music, and it's easy to imagine people sticking to one or the other. Ad-free videos have been getting the most aggressive promotion lately, with Google cracking down on ad-block users by blocking video playback and displaying interstitial pop-ups. After warning users that ad blockers violate YouTube's terms of service, the pop-ups show a big "try YouTube Premium" button. Premium also added an exclusive "enhanced bitrate" 1080p setting, although 2K, 4K, and 8K options have always been free.
There's not much new on the music side of things. YouTube Music is free with ads and a more limited feature set, but subscribing gets you ad-free playback, background playback on phones, and access to YouTube Music streaming on Google's various speakers. YouTube's blog post highlights quotes from many big music industry CEOs celebrating the service.
Tesla’s week gets worse: Fines, safety investigation, and massive recall
Enlarge / More than 2,000 Tesla model-year 2023 Model Y and Model 3s have suffered steering failure, according to a new NHTSA safety defect investigation. (credit: Sjoerd van der Wal/Getty Images)
It's been a rough week for Tesla. On Tuesday, a court in Delaware voided a massive $55.8 billion pay package for CEO Elon Musk. Then, news emerged that Tesla was being sued by 25 different counties in California for years of dumping toxic waste. That was followed by a recall affecting 2.2 million Teslas. Now, Ars has learned that the National Highway Traffic Safety Administration's Office of Defects Investigation is investigating the company after 2,388 complaints of steering failure affecting the model-year 2023 Model 3 sedan and Model Y crossover.
Paint, brake fluid, used batteries, antifreeze, dieselTesla has repeatedly run afoul of laws designed to protect the environment from industrial waste. In 2019, author Edward Niedermeyer cataloged the troubles the company ran into with air pollution from its paint shop in Fremont, California, some of which occurred when the automaker took to painting its cars in a temporary tent-like marquee.
In 2022, the US Environmental Protection Agency fined Tesla $275,000 for violating the Clean Air Act, which followed a $31,000 penalty Tesla paid to the EPA in 2019. But EPA data shows that Tesla continued to violate the Clean Air Act in 2023.
Daily Telescope: A Wolf-Rayet star puts on a howling light show
Enlarge / The Crescent Nebula. (credit: 1Zach1)
Welcome to the Daily Telescope. There is a little too much darkness in this world and not enough light, a little too much pseudoscience and not enough science. We'll let other publications offer you a daily horoscope. At Ars Technica, we're going to take a different route, finding inspiration from very real images of a universe that is filled with stars and wonder.
Good morning. It's February 2, and today's image concerns an emission nebula about 5,000 light-years away in the Cygnus constellation.
Discovered more than 230 years ago by William Herschel, astronomers believe the Crescent Nebula is formed by the combination of an energetic stellar wind from a Wolf-Rayet star at its core, colliding with slower-moving material ejected earlier in the star's lifetime. Ultimately, this should all go supernova, which will be quite spectacular.
Why interstellar objects like ‘Oumuamua and Borisov may hold clues to exoplanets
Enlarge / The first interstellar interloper detected passing through the Solar System, 1l/‘Oumuamua, came within 24 million miles of the Sun in 2017. It’s difficult to know exactly what ‘Oumuamua looked like, but it was probably oddly shaped and elongated, as depicted in this illustration. (credit: NASA, ESA, JOSEPH OLMSTED (STSCI), FRANK SUMMERS (STSCI))
On October 17 and 18, 2017, an unusual object sped across the field of view of a large telescope perched near the summit of a volcano on the Hawaiian island of Maui. The Pan-STARRS1 telescope was designed to survey the sky for transient events, like asteroid or comet flybys. But this was different: The object was not gravitationally bound to the Sun or to any other celestial body. It had arrived from somewhere else.
The mysterious object was the first visitor from interstellar space observed passing through the Solar System. Astronomers named it 1I/‘Oumuamua, borrowing a Hawaiian word that roughly translates to “messenger from afar arriving first.” Two years later, in August 2019, amateur astronomer Gennadiy Borisov discovered the only other known interstellar interloper, now called 2I/Borisov, using a self-built telescope at the MARGO observatory in Nauchnij, Crimea.
While typical asteroids and comets in the Solar System orbit the Sun, ‘Oumuamua and Borisov are celestial nomads, spending most of their time wandering interstellar space. The existence of such interlopers in the Solar System had been hypothesized, but scientists expected them to be rare. “I never thought we would see one,” says astrophysicist Susanne Pfalzner of the Jülich Supercomputing Center in Germany. At least not in her lifetime.
Rocket Report: SpaceX at the service of a rival; Endeavour goes vertical
Enlarge / Space shuttle Endeavour, seen here in protective wrapping, was mounted on an external tank and inert solid rocket boosters at the California Science Center. (credit: California Science Center)
Welcome to Edition 6.29 of the Rocket Report! Right now, SpaceX's Falcon 9 rocket is the only US launch vehicle offering crew or cargo service to the International Space Station. The previous version of Northrop Grumman's Antares rocket retired last year, forcing that company to sign a contract with SpaceX to launch its Cygnus supply ships to the ISS. And we're still waiting on United Launch Alliance's Atlas V (no fault of ULA) to begin launching astronauts on Boeing's Starliner crew capsule to the ISS. Basically, it's SpaceX or bust. It's a good thing that the Falcon 9 has proven to be the most reliable rocket in history.
As always, we welcome reader submissions, and if you don't want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets, as well as a quick look ahead at the next three launches on the calendar.
Virgin Galactic flies four passengers to the edge of space. Virgin Galactic conducted its first suborbital mission of 2024 on January 26 as the company prepares end flights of its current spaceplane, Space News reports. The flight, called Galactic 06 by Virgin Galactic, carried four customers for the first time, along with its two pilots, on a suborbital hop over New Mexico aboard the VSS Unity rocket plane. Previous commercial flights had three customers on board, along with a Virgin Galactic astronaut trainer. The customers, which Virgin Galactic didn't identify until after the flight, held US, Ukrainian, and Austrian citizenship.
Convicted console hacker says he paid Nintendo $25 a month from prison
Enlarge / It's-a me, the long arm of the law. (credit: Aurich Lawson / Nintendo / Getty Images)
When 54-year-old Gary Bowser pleaded guilty to his role in helping Team Xecuter with their piracy-enabling line of console accessories, he realized he would likely never pay back the $14.5 million he owed Nintendo in civil and criminal penalties. In a new interview with The Guardian, though, Bowser says he began making $25 monthly payments toward those massive fines even while serving a related prison sentence.
Last year, Bowser was released after serving 14 months of that 40-month sentence (in addition to 16 months of pre-trial detention), which was spread across several different prisons. During part of that stay, Bowser tells The Guardian, he was paid $1 an hour for four-hour shifts counseling other prisoners on suicide watch.
From that money, Bowser says he “was paying Nintendo $25 a month” while behind bars. That lines up roughly with a discussion Bowser had with the Nick Moses podcast last year, where he said he had already paid $175 to Nintendo during his detention.
Agencies using vulnerable Ivanti products have until Saturday to disconnect them
Enlarge (credit: Getty Images)
Federal civilian agencies have until midnight Saturday morning to sever all network connections to Ivanti VPN software, which is currently under mass exploitation by multiple threat groups. The US Cybersecurity and Infrastructure Security Agency mandated the move on Wednesday after disclosing three critical vulnerabilities in recent weeks.
Three weeks ago, Ivanti disclosed two critical vulnerabilities that it said threat actors were already actively exploiting. The attacks, the company said, targeted “a limited number of customers” using the company’s Connect Secure and Policy Secure VPN products. Security firm Volexity said on the same day that the vulnerabilities had been under exploitation since early December. Ivanti didn’t have a patch available and instead advised customers to follow several steps to protect themselves against attacks. Among the steps was running an integrity checker the company released to detect any compromises.
Almost two weeks later, researchers said the zero-days were under mass exploitation in attacks that were backdooring customer networks around the globe. A day later, Ivanti failed to make good on an earlier pledge to begin rolling out a proper patch by January 24. The company didn’t start the process until Wednesday, two weeks after the deadline it set for itself.
Cops arrest 17-year-old suspected of hundreds of swattings nationwide
Enlarge / Booking photo of Alan Filion, charged with multiple felonies connected to a "swatting" incident at the Masjid Al Hayy Mosque in Sanford, Florida. (credit: Seminole County Sheriff's Office)
Police suspect that a 17-year-old from California, Alan Filion, may be responsible for "hundreds of swatting incidents and bomb threats" targeting the Pentagon, schools, mosques, FBI offices, and military bases nationwide, CNN reported.
Swatting occurs when fraudulent calls to police trigger emergency response teams to react forcefully to non-existent threats.
Recently extradited to Florida, Filion was charged with multiple felonies after the Seminole County Sheriff’s Office (SCSO) traced a call where Filion allegedly claimed to be a mass shooter entering the Masjid Al Hayy Mosque in Sanford, Florida. The caller played "audio of gunfire in the background," SCSO said, while referencing Satanism and claiming he had a handgun and explosive devices.
FCC to declare AI-generated voices in robocalls illegal under existing law
Enlarge (credit: Getty Images | Thamrongpat Theerathammakorn)
The Federal Communications Commission plans to vote on making the use of AI-generated voices in robocalls illegal. The FCC said that AI-generated voices in robocalls have "escalated during the last few years" and have "the potential to confuse consumers with misinformation by imitating the voices of celebrities, political candidates, and close family members."
FCC Chairwoman Jessica Rosenworcel's proposed Declaratory Ruling would rule that "calls made with AI-generated voices are 'artificial' voices under the Telephone Consumer Protection Act (TCPA), which would make voice cloning technology used in common robocalls scams targeting consumers illegal," the commission announced yesterday. Commissioners reportedly will vote on the proposal in the coming weeks.
A recent anti-voting robocall used an artificially generated version of President Joe Biden's voice. The calls told Democrats not to vote in the New Hampshire Presidential Primary election.
Google’s Pixel storage issue fix requires developer tools and a terminal
Enlarge (credit: Getty Images)
Google has another fix for the second major storage bug Pixel phones have seen in the last four months. Last week, reports surfaced that some Pixel owners were being locked out of their phone's local storage, creating a nearly useless phone with all sorts of issues. Many blamed the January 2024 Google Play system update for the issue, and yesterday, Google confirmed that hypothesis. Google posted an official solution to the issue on the Pixel Community Forums, but there's no user-friendly solution here. Google's automatic update system broke people's devices, but the fix is completely manual, requiring users to download the developer tools, install drivers, change settings, plug in their phones, and delete certain files via a command-line interface.
The good news is that, if you've left your phone sitting around in a nearly useless state for the last week or two, following the directions means you won't actually lose any data. Having a week or two of downtime is not acceptable to a lot of people, though, and several users replied to the thread saying they had already wiped their device to get their phone working again and had to deal with the resulting data loss (despite many attempts and promises, Android does not have a comprehensive backup system that works).
The bad news is that I don't think many normal users will be able to follow Google's directions. First, you'll need to perform the secret action to enable Android's Developer Options (you tap on the build number seven times). Then, you have to download Google's "SDK Platform-Tools" zip file, which is meant for app developers. After that, plug in your phone, switch to the correct "File transfer" connection mode, open a terminal, navigate to the platform-tools folder, and run both “./adb uninstall com.google.android.media.swcodec” and “./adb uninstall com.google.android.media." Then reboot the phone and hope that works.
Hulu, Disney+ password crackdown kills account sharing on March 14
Enlarge / Selena Gomez and Martin Short on the set of Only Murders in the Building on February 14, 2022, in New York City.
Hulu and Disney+ subscribers have until March 14 to stop sharing their login information with people outside of their household. Disney-owned streaming services are the next to adopt the password-crackdown strategy that has helped Netflix add millions of subscribers.
An email sent from "The Hulu Team" to subscribers yesterday and viewed by Ars Technica tells customers that Hulu is "adding limitations on sharing your account outside of your household."
Hulu's subscriber agreement, updated on January 25, now states that users "may not share your subscription outside of your household," with household being defined as the "collection of devices associated with your primary personal residence that are used by the individuals who reside therein."
Starlab—with half the volume of the ISS—will fit inside Starship’s payload bay
Enlarge / An artist's concept of the Starlab space station. (credit: Starlab LLC)
The Starlab commercial space station will launch on SpaceX's Starship rocket, officials said this week.
Starlab is a joint venture between the US-based Voyager Space and the European-based multinational aerospace corporation Airbus. The venture is building a large station with a habitable volume equivalent to half the pressurized volume of the International Space Station and will launch the new station no earlier than 2028.
"SpaceX's history of success and reliability led our team to select Starship to orbit Starlab," Dylan Taylor, chairman and CEO of Voyager Space, said in a statement. "SpaceX is the unmatched leader for high-cadence launches and we are proud Starlab will be launched to orbit in a single flight by Starship."
Clownfish “count” white stripes to determine if an invader is friend or foe
Enlarge / Clown anemonefish (Amphiprion ocellaris) seem to recognize different species of clownfish by counting white stripes. (credit: Kina Hayashi)
Many people tend to think of clownfish, with their distinctive white bars against an orange, red, or black background, as a friendly sort of fish, perhaps influenced to some extent by the popular Pixar film Finding Nemo. But clownfish can be quite territorial when it comes to defending their host anemone from intrusion by others, particularly those from their own species. A new paper published in the Journal of Experimental Biology describes how clownfish determine if a fish approaching their home is friend or foe by "counting" the number of white bars or stripes on their bodies.
As previously reported, mathematical ability is often considered uniquely human, but in fact, scientists have found that many animal species—including lions, chimpanzees, birds, bees, ants, and fish—seem to possess at least a rudimentary counting ability or number sense. Crows can understand the concept of zero. So can bees, which can also add and subtract, as can both stingrays and cichlids—at least for a small number of objects (in the range of one to five). Some ants count their steps.
This so-called "numerosity" simply refers to the number of things in a set, according to cognitive psychologist Brian Butterworth, an emeritus professor at University College London and author of Can Fish Count? What Animals Reveal About Our Uniquely Mathematical Minds. It has nothing to do with reasoning or logical mathematical intelligence. This is information that will be in the environment, and counting animals must have some mechanism for extracting this numerical information from the environment. But it nonetheless makes for a fascinating field of study.
Palworld’s Pokémon pastiche is Xbox Game Pass’ biggest-ever 3rd-party game launch
Enlarge (credit: Pocketpair)
The unexpected success of Palworld continues to be one of the biggest gaming stories of 2024 so far, as developer Pocketpair says the game's sales and Xbox downloads have exceeded 19 million, with 12 million in sales on Steam and 7 million players on Xbox. Microsoft has also announced that the game has been the biggest third-party launch in the Game Pass service's history, as well as the most-played third-party title on the Xbox Cloud Gaming service.
These numbers continue a remarkable run for the indie-developed Pokémon-survival-crafting-game pastiche, which sold 5 million copies in its first weekend as a Steam Early Access title and had sold 8 million Steam copies as of a week ago. There are signs that the game's sales are slowing down—it's currently Steam's #2 top-selling game after over a week in the #1 spot. But its active player count on Steam remains several hundred thousand players higher than Counter-Strike 2, the next most-played game on the platform.
Sometimes described (both admiringly and disparagingly) as "Pokémon with guns," Palworld's unexpected success has driven some Internet outrage cycles about the possibility that it may have used AI-generated monster designs and allegations that its designers copied or modified some of the 3D character models from the actual Pokémon series to create some of the game's more familiar-looking monsters.
Elon Musk proposes Tesla move to Texas after Delaware judge voids $56 billion pay
Enlarge / Tesla CEO Elon Musk speaks at Tesla's "Cyber Rodeo" on April 7, 2022, in Austin, Texas. (credit: Getty Images | AFP/Suzanne Cordeiro)
Tesla CEO Elon Musk has had enough of Delaware after a state court ruling voided his $55.8 billion pay package. Musk said last night that Tesla will hold a shareholder vote on transferring the electric carmaker's state of incorporation to Texas.
Musk had posted a poll on X (formerly Twitter) asking whether Tesla should "change its state of incorporation to Texas, home of its physical headquarters." After over 87 percent of people voted yes, Musk wrote, "The public vote is unequivocally in favor of Texas! Tesla will move immediately to hold a shareholder vote to transfer state of incorporation to Texas."
Tesla was incorporated in 2003 before Musk joined the company. Its founders chose Delaware, a common destination because of the state's low corporate taxes and business-friendly legal framework. The Delaware government says that over 68 percent of Fortune 500 companies are registered in the state, and 79 percent of US-based initial public offerings in 2022 were registered in Delaware.
eBay to pay $59M after DOJ ties pill press sales to fentanyl drug rings
Enlarge (credit: Iryna Imago | iStock / Getty Images Plus)
eBay has agreed to pay $59 million after the US Department of Justice accused the online marketplace of selling thousands of pill presses and encapsulating machines, some of which were used by rings trafficking in illegal counterfeit pills.
It's the fourth largest settlement under the Controlled Substances Act (CSA) and the first-ever settlement with an e-commerce company, a DOJ press release noted.
“Through its website, eBay made it easy for individuals across the country to obtain the type of dangerous machines that are often used to make counterfeit pills," Nikolas Kerest, US attorney for the District of Vermont, said. "Our investigation revealed that some of these machines were even sold to individuals who were later convicted of drug-related crimes."
For the first time NASA has asked industry about private missions to Mars
Enlarge / NASA is interested in whether private companies have the right stuff for Mars. (credit: NASA)
NASA is starting to take its first steps toward opening a commercial pathway to Mars.
This week, the space agency's Jet Propulsion Laboratory issued a new solicitation to the industry titled "Exploring Mars Together: Commercial Services Studies." This is a request for proposals from the US space industry to tell NASA how they would complete one of four private missions to Mars, including delivering small satellites into orbit or providing imaging services around the red planet.
"The Mars Exploration Program Draft Plan through the next two decades would utilize more frequent lower cost missions to achieve compelling science and exploration for a larger community," the document states. "To realize the goals of the plan, government and US industry would partner to leverage current and emerging Earth and lunar products and commercial services to substantially lower the overall cost and accelerate leadership in deep space exploration."
Exploring Reddit’s third-party app environment 7 months after the APIcalypse
Last year, Reddit sparked massive controversy when it dramatically changed the prices and rules associated with accessing its API. The changes were so drastic and polarizing that they led to an epic protest from Reddit users and moderators that saw thousands of subreddits going private and engaging in other forms of inconvenience for weeks. Things got ugly, but Reddit still ushered in the changes, resulting in mounds of third-party Reddit apps announcing their permanent closure.
It's been about seven months since the changes, so I wanted to see what Reddit's third-party app ecosystem looks like now. Are surviving third-party Reddit apps that started charging users making money? Are developers confident they'll be able to keep their apps open for the long term?
And some apps are still available despite not charging a subscription fee. How is that possible?