A patch of desert that neither Egypt nor Sudan will claim, an AI that rebuilds what you're looking at from a brain scan, and the world's most accurate atomic clock. Plus why forgotten subscriptions earn firms so much. [DVYio Newsletter](https://newsletter.dvy.io/visit/HUVmV62W) This Week I Learnt [Map of Egypt and Sudan; a red arrow marks Bir Tawil as having undetermined status, while Hala’ib is labeled claimed by Sudan and administered by Egypt.](https://newsletter.dvy.io/visit/AVmp6taX) [There's a 2,060km² patch of desert between Egypt and Sudan that neither country wants](https://newsletter.dvy.io/visit/AVmp6taX) [Bir Tawil is a 2,060km² patch of desert between Egypt and Sudan that neither country will claim. An 1899 treaty drew the border along the 22nd parallel (a line of latitude). That put the Hala'ib Triangle in Egypt and Bir Tawil in Sudan. Then in 1902 Britain drew a separate “administrative boundary” to match how local tribes actually used the land. That put Hala'ib under Sudanese administration and Bir Tawil under Egyptian administration. Egypt now insists on the 1899 line because it gives Egypt Hala'ib, which has coastline and people. Sudan insists on the 1902 line for the same reason. Both versions agree on one thing: whoever gets the valuable Hala'ib Triangle also gets stuck rejecting the less valuable bit next door. So each country claims the coastal territory it wants and disowns the desert it doesn't. Bir Tawil, a tenth the size of Hala'ib with no sea access and no permanent towns, ends up unclaimed by any country.](https://newsletter.dvy.io/visit/AVmp6taX) [That makes it one of Earth's few habitable areas with no claim from any recognised government, according to a 2024 Nine News report. It's not actually empty, though. Ababda and Bishari tribespeople pass through, and unregulated gold-mining camps have sprung up. Tour operator Young Pioneer Tours ran visits there in 2019 and 2024. They claim arms dealers and mercenaries linked to Sudan's civil war also operate there. Because no country claims Bir Tawil, it's attracted people online trying to declare their own micronation (a self-declared state). They try to plant flags and call themselves king, but no government has recognised these claims. Young Pioneer Tours say people living and working there dislike these claims and are armed well enough to repel would-be occupiers.](https://newsletter.dvy.io/visit/AVmp6taX) Tech [A grid pairs photos with similar reconstructed scenes, including clock towers, sleepers, giraffes, beaches, skiers, and birds.](https://newsletter.dvy.io/visit/D7EuYAxu) [An AI tool can reconstruct what you’re looking at from a brain scan](https://newsletter.dvy.io/visit/D7EuYAxu) Michal Irani's research team at the Weizmann Institute says its AI needs just one hour of brain scans from a new person. Other brain-reading tools typically need about 40 hours before they can work out what that person is looking at. Irani's team trained one AI to guess a brain scan from a picture and another to rebuild the picture from the scan. The two teach each other, allowing about 70% of their training images to be used without a real scan. [A smart contact lens detects serotonin in tears and converts it to a signal estimating stress, without a blood draw or questionnaire.](https://newsletter.dvy.io/visit/DDeFBFWB) [Researchers build a contact lens that reads stress levels from serotonin in tears](https://newsletter.dvy.io/visit/DDeFBFWB) Researchers are developing a smart contact lens that measures tiny traces of serotonin in tears, a potential way to track stress without a blood draw or a questionnaire. It's an early prototype: the team tested tears from 10 volunteers in lab dishes, not while the volunteers wore the lenses. The sensor detected lower serotonin levels after stressful tasks. [Chart shows subscription retention falling from 100% at month 1 to 73% by month 11, then dropping to 60% at month 12 when a replacement card requires active re-subscription, and declining to 40% by month 24. The study reports cancellations are about four times faster in these months.](https://newsletter.dvy.io/visit/qhqrLcVz) [Forgotten subscriptions roughly double seller revenue, and AI agents don't forget](https://newsletter.dvy.io/visit/qhqrLcVz) A 2025 study by Liran Einav, Ben Klopack, and Neale Mahoney examined why people keep paying for unwanted subscriptions. Their models estimate that inattention or cancellation difficulties roughly double sellers' revenue on average, compared with removing those barriers. The comparison keeps the initial subscriber group fixed. Cancellations jumped when replacement payment cards meant customers had to actively renew. AI agents such as Muse, Instinct, and Grok Bot can now scan your accounts and force that same decision for every subscription you've forgotten about, which is bad news for any business quietly relying on you not noticing. Poll When someone sends you a long voice note, what do you do? Listen immediately Save it for later Read the transcript Avoid opening it Last Week's Poll When you read silently, do you hear the words in a voice? Always, in my own voice 33% Always, but no specific voice 23% Sometimes 17% Only if I deliberately slow down 10% Not at all 17% Last week's poll asked whether you hear a voice when you read silently. A sixth of you said “Not at all”, so I dug into this. In a 2017 survey of 570 people, psychologist Ruvanee Vilhauer found that 80.7% sometimes or always hear an inner voice. The remaining 19.3% don't. Neither her survey nor my poll is a solid population estimate (both samples are self-selected), but the split is similar. Among those who do hear a voice, it varies: your own or someone else's, with different accents and tones. “Hearing a voice” also isn't one single thing. In a 2012 study, researchers recorded brain activity from electrodes implanted in four epilepsy patients. The electrodes were there for medical reasons. Written words switched on brain areas involved in hearing, more strongly when the patients paid attention. Four people can't speak for everyone, though. Some people have a weaker ability to imagine sounds, and having none at all is called anauralia. Quoted speech like Maya said, “That's wonderful!” also triggers more activity in brain areas involved in hearing voices than Maya said that it was wonderful. Science [Three researchers examine a complex optical laboratory setup, with one pointing toward the equipment.](https://newsletter.dvy.io/visit/DLKHuCCz) [Scientists build world's most accurate atomic clock](https://newsletter.dvy.io/visit/DLKHuCCz) Singapore's Centre for Quantum Technologies has built an atomic clock using the element lutetium. A comparison with a twin clock was sensitive enough to detect gravity slowing time across a height difference of just 5mm. The team compared the clocks on the same table. Earth's gravity isn't mapped well enough to compare clocks between labs at this level. The team says it's the most accurate clock in the world. Its estimated relative uncertainty is about 1 × 10⁻¹⁹ (roughly one part in ten billion billion). Over 200 hours, the two clocks agreed within a relative uncertainty of 5.7 × 10⁻¹⁹. [Diagram proposes myelin absorbs protons during sleep, then releases them while awake to make ATP and support brain function.](https://newsletter.dvy.io/visit/8axEnSTa) [Nerve insulation may store energy during sleep and release that energy while we're awake, a new hypothesis says](https://newsletter.dvy.io/visit/8axEnSTa) Researchers Alessandro Morelli, Ann Saada, and Felix Scholkmann propose that sleep works a bit like plugging in a phone overnight. In their hypothesis, myelin (the fatty insulation wrapped around nerve fibres) soaks up protons (tiny charged particles) while you sleep. It then uses them to make ATP, a molecule cells use for energy, while you're awake. It's an untested idea in a review paper. Their rough calculation says the human brain would need about 8 hours of sleep to recharge this way. [Two technicians work among dense laser and electrical equipment installed inside an aircraft cabin.](https://newsletter.dvy.io/visit/XCCEApsF) [Researchers beam energy from a moving aircraft to test space solar power](https://newsletter.dvy.io/visit/XCCEApsF) Overview Energy, a startup in Northern Virginia, has beamed power from a plane to solar panels on the ground, as a test of its plan to deliver solar energy from space. Lasers on a Cessna Caravan flying 5km up sent the energy down. A tracking system kept them aimed at the panels as the plane moved. The idea is that satellites can collect sunlight without the atmosphere in the way and keep supplying power at night. Overview say the test equipment is largely identical to what they intend to launch. They plan an orbital test for 2028 and a first solar farm at 36,000km in 2029 or 2030. [Illustration links sugary foods during pregnancy and early childhood with an anxious adult woman.](https://newsletter.dvy.io/visit/uoH3n4bC) [Exposure to sugar in the first 1,000 days from conception is linked to higher anxiety risk in adulthood](https://newsletter.dvy.io/visit/uoH3n4bC) Researchers at the University of Surrey studied over 45,000 UK adults born between 1951 and 1956. They compared people exposed to different lengths of post-war sugar rationing before birth and in early childhood. Those exposed to rationing in the womb and throughout their first two years had the lowest anxiety risk. They also reported liking sweet food less. It shows a link, not proof of cause. [Casa Azaleas, a minimalist beige concrete house with a flat roof, dark recessed entrance, and small upper window, framed by lush greenery and irregular stone paving.](https://newsletter.dvy.io/visit/eMcLkSuR) [A serene interior courtyard with warm wood walls, pale stone steps, a central leafy tree, and a geometric skylight.](https://newsletter.dvy.io/visit/eMcLkSuR) [Interior courtyard of Casa Azaleas with warm wood steps and benches, pale plaster walls, a geometric ceiling, and a small cluster of plants.](https://newsletter.dvy.io/visit/eMcLkSuR) [Sunlit minimalist entry hall with pale stone walls, a wood-paneled cabinet, and an open door overlooking a leafy courtyard.](https://newsletter.dvy.io/visit/eMcLkSuR) [Casa Azaleas interior in Guadalajara, with a tall wood-clad column, pale concrete ceilings, a lounge, and a planted courtyard.](https://newsletter.dvy.io/visit/eMcLkSuR) [A minimalist interior with a tall wood-slat partition, pale stone walls, tiled floor, and a grid of skylights.](https://newsletter.dvy.io/visit/eMcLkSuR) [A shaded garden entry framed by rough concrete walls and a broad roof, with stepping stones winding through dense tropical plants.](https://newsletter.dvy.io/visit/eMcLkSuR) [A lush indoor garden fills a concrete courtyard, with large tropical leaves, climbing vines, and connected partition walls beneath a flat roof.](https://newsletter.dvy.io/visit/eMcLkSuR) [Casa Azaleas](https://newsletter.dvy.io/visit/eMcLkSuR) [Guadalajara, Mexico](https://newsletter.dvy.io/visit/eMcLkSuR) Data [“Have a lot of fun” most strongly correlates with high life satisfaction; feeling misunderstood is prominent for low satisfaction.](https://newsletter.dvy.io/visit/PKPwh2Bi) [Study of 21,000+ people finds life satisfaction closely tracks personality, with “having a lot of fun” the strongest positive link](https://newsletter.dvy.io/visit/PKPwh2Bi) [Researchers tested how closely a person's life satisfaction matches their personality. They used three groups tested in different languages: 20,886 people in Estonian, 768 in Russian, and 600 in English. Older studies had a weakness: people rated their personality and their life on the same form. A bad mood that day could colour both answers. This study also collected ratings from people who know the participants, and it adjusted for mood on the day and for random errors.](https://newsletter.dvy.io/visit/PKPwh2Bi) [With those fixes, personality predicted life satisfaction very well, at about .80 to .90 (1 would be a perfect match). Emotional stability (staying calm), extraversion (being outgoing), and conscientiousness (being organised and hardworking) each scored about .30 to .50. Openness and agreeableness scored low. The strongest positive link was with “Have a lot of fun” (.60), and the strongest negative one was “Often feel that others misunderstand me” (-.69). Life satisfaction also stayed fairly steady over about ten years (.70). These are links, not proof of cause. Feeling misunderstood could be a result of an unhappy life rather than the reason for it.](https://newsletter.dvy.io/visit/PKPwh2Bi) [Image from](https://newsletter.dvy.io/visit/PKPwh2Bi)[@NTFabiano](https://newsletter.dvy.io/visit/5Kvjgd3Y) History [Illustrated bust of a Japanese samurai in patterned armor, shown in profile facing right.](https://newsletter.dvy.io/visit/pX2i7TZe) [Why Italian fascists loved Samurai](https://newsletter.dvy.io/visit/pX2i7TZe) [Italian Fascists drew much of their image of Japan's samurai warriors from](https://newsletter.dvy.io/visit/pX2i7TZe)[Bushido: The Soul of Japan](https://newsletter.dvy.io/visit/pX2i7TZe)[(1900). Its author, Japanese diplomat Nitobe Inazō, wrote in English to present samurai to Westerners as Japan's chivalrous knights. Real samurai had been sidelined as Japan modernised, so the Fascists could pick the bits they liked, such as honourable death. Mussolini gave a speech to Japanese youth about bushido (the samurai warrior code) and its similarities to Fascism. The invitation came via the soft drink company Calpis, according to modern Italian studies scholar Michele Monserrati.](https://newsletter.dvy.io/visit/pX2i7TZe) [Black-and-white photo of children seated at desks outdoors while a teacher stands before a small chalkboard classroom surrounded by foliage.](https://newsletter.dvy.io/visit/ezTC4wUv) [Classrooms without walls: a forgotten age of open-air schools](https://newsletter.dvy.io/visit/ezTC4wUv) Open-air schools were built to fight tuberculosis with fresh air. The movement began with the Waldeschule (“forest school”), which opened in Charlottenburg, Germany, in 1904. Britain had 96 open-air day schools by 1937. By the 1930s, sliding doors and retractable roofs let a classroom open onto a terrace. Antibiotics and better living conditions made them less necessary after the Second World War. Random [A cheeseburger sits before a hazy city skyline, illustrating Columbus as a testing ground for fast-food products.](https://newsletter.dvy.io/visit/SjM4RpSS) [Companies test new food products in Columbus, Ohio, because it's a close match for America as a whole](https://newsletter.dvy.io/visit/SjM4RpSS) [Axios explains why food companies keep trialling new products in Columbus, Ohio. Burger King was testing King Size Sliders there, after earlier trying a Pretzel Whopper and Nacho Chicken Fries. Taco Bell tested Tajín shells last year, and Wendy's first AI drive-thrus were local too. The reputation goes back decades, partly because Wendy's and White Castle tested close to their headquarters. But the pitch now is variety: city, suburb, and countryside sit close together, and the population includes students, families, and immigrants. John Barker, who used to be a Wendy's vice president, says a hit in Columbus suggests it will do well across most of the US. But Columbus has a below-average share of Latino residents, which an Ohio State lecturer says could become a disadvantage.](https://newsletter.dvy.io/visit/SjM4RpSS) [A pop-up book of space shows planets and a small astronaut beside a deep, funnel-shaped black hole with a glowing center.](https://newsletter.dvy.io/visit/S8d8FRMT) [Black hole entropy tracks surface area, not volume, and physicists think that hints space is a hologram](https://newsletter.dvy.io/visit/S8d8FRMT) The holographic principle says that if you draw a box around any region of space, measuring only the surface of the box should tell you everything inside it, so the amount of stuff filling the box matches the amount of paint covering it. In the 1970s, physicists Jacob Bekenstein and Stephen Hawking found that a black hole's entropy grows with its surface area, not its volume. Entropy measures how many microscopic arrangements could produce the same outward appearance. But University of Edinburgh physicist Latham Boyle suspects this is a separate “entanglement” entropy, measuring quantum connections across the boundary. He doesn't consider it proof that space is a hologram. Design [“Clipart Studio” logo over a collage of vintage maps, artwork, botanical prints, and photographs, surrounded by cutout objects on a green grid.](https://newsletter.dvy.io/visit/BSCiLWJ9) [Clipart Studio lets you make collages from magazine clippings](https://newsletter.dvy.io/visit/BSCiLWJ9) [Clipart Studio is a free web tool by Sami Smith that lets you make collages the way you would with scissors and old magazines. You open a magazine, or upload your own PDF or image, then snip out clippings and arrange them on a canvas.](https://newsletter.dvy.io/visit/BSCiLWJ9) [A green wool jumper featuring a cartoon of Nvidia CEO Jensen Huang hangs above folded matching jumpers in a shop.](https://newsletter.dvy.io/visit/HL7DKV7L) [Would you buy branded clothing from your favourite tech firm?](https://newsletter.dvy.io/visit/HL7DKV7L) A BBC feature looks at tech firms selling branded clothing, usually in tiny, short-lived releases. Chip maker Nvidia's $178 woollen jumper carries a cartoon of its boss, Jensen Huang. Palantir, the US software firm criticised for its military and police work, now calls itself a “lifestyle brand”. “If you rip a hole in a net, there are fewer holes than before.” Anonymous [Web](https://newsletter.dvy.io/visit/Wrq5oBt3) · [Twitter](https://newsletter.dvy.io/visit/YBMHBiV6) · [LinkedIn](https://newsletter.dvy.io/visit/VADj4EKy)