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Microsoft and Atom Computing combine for quantum error correction demo

19 November 2024 at 21:00

In September, Microsoft made an unusual combination of announcements. It demonstrated progress with quantum error correction, something that will be needed for the technology to move much beyond the interesting demo phase, using hardware from a quantum computing startup called Quantinuum. At the same time, however, the company also announced that it was forming a partnership with a different startup, Atom Computing, which uses a different technology to make qubits available for computations.

Given that, it was probably inevitable that the folks in Redmond, Washington, would want to show that similar error correction techniques would also work with Atom Computing's hardware. It didn't take long, as the two companies are releasing a draft manuscript describing their work on error correction today. The paper serves as both a good summary of where things currently stand in the world of error correction, as well as a good look at some of the distinct features of computation using neutral atoms.

Atoms and errors

While we have various technologies that provide a way of storing and manipulating bits of quantum information, none of them can be operated error-free. At present, errors make it difficult to perform even the simplest computations that are clearly beyond the capabilities of classical computers. More sophisticated algorithms would inevitably encounter an error before they could be completed, a situation that would remain true even if we could somehow improve the hardware error rates of qubits by a factor of 1,000—something we're unlikely to ever be able to do.

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Scientist behind superconductivity claims ousted

19 November 2024 at 17:46

University of Rochester physicist Ranga Dias made headlines with his controversial claims of high-temperature superconductivity—and made headlines again when the two papers reporting the breakthroughs were later retracted under suspicion of scientific misconduct, although Dias denied any wrongdoing. The university conducted a formal investigation over the past year and has now terminated Dias' employment, The Wall Street Journal reported.

“In the past year, the university completed a fair and thorough investigation—conducted by a panel of nationally and internationally known physicists—into data reliability concerns within several retracted papers in which Dias served as a senior and corresponding author,” a spokesperson for the University of Rochester said in a statement to the WSJ, confirming his termination. “The final report concluded that he engaged in research misconduct while a faculty member here.”

The spokesperson declined to elaborate further on the details of his departure, and Dias did not respond to the WSJ's request for comment. Dias did not have tenure, so the final decision rested with the Board of Trustees after a recommendation from university President Sarah Mangelsdorf. Mangelsdorf had called for terminating his position in an August letter to the chair and vice chair of the Board of Trustees, so the decision should not come as a surprise. Dias' lawsuit claiming that the investigation was biased was dismissed by a judge in April.

Ars has been following this story ever since Dias first burst onto the scene with reports of a high-pressure, room-temperature superconductor, published in Nature in 2020. Even as that paper was being retracted due to concerns about the validity of some of its data, Dias published a second paper in Nature claiming a similar breakthrough: a superconductor that works at high temperatures but somewhat lower pressures. Shortly afterward, that paper was retracted as well. As Ars Science Editor John Timmer reported previously:

Dias' lab was focused on high-pressure superconductivity. At extreme pressures, the orbitals where electrons hang out get distorted, which can alter the chemistry and electronic properties of materials. This can mean the formation of chemical compounds that don't exist at normal pressures, along with distinct conductivity. In a number of cases, these changes enabled superconductivity at unusually high temperatures, although still well below the freezing point of water.

Dias, however, supposedly found a combination of chemicals that would boost the transition to superconductivity to near room temperature, although only at extreme pressures. While the results were plausible, the details regarding how some of the data was processed to produce one of the paper's key graphs were lacking, and Dias didn't provide a clear explanation.

The ensuing investigation cleared Dias of misconduct for that first paper. Then came the second paper, which reported another high-temperature superconductor forming at less extreme pressures. However, potential problems soon became apparent, with many of the authors calling for its retraction, although Dias did not.

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Emergent gravity may be a dead idea, but it’s not a bad one

19 November 2024 at 15:19

Emergent gravity is a bold idea.

It claims that the force of gravity is a mere illusion, more akin to friction or heat—a property that emerges from some deeper physical interaction. This emergent gravity idea might hold the key to rewriting one of the fundamental forces of nature—and it could explain the mysterious nature of dark matter.

But in the years since its original proposal, it has not held up well to either experiment or further theoretical inquiry. Emergent gravity may not be a right answer. But it is a clever one, and it's still worth considering, as it may hold the seeds of a greater understanding.

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IBM boosts the amount of computation you can get done on quantum hardware

13 November 2024 at 22:42

There's a general consensus that we won't be able to consistently perform sophisticated quantum calculations without the development of error-corrected quantum computing, which is unlikely to arrive until the end of the decade. It's still an open question, however, whether we could perform limited but useful calculations at an earlier point. IBM is one of the companies that's betting the answer is yes, and on Wednesday, it announced a series of developments aimed at making that possible.

On their own, none of the changes being announced are revolutionary. But collectively, changes across the hardware and software stacks have produced much more efficient and less error-prone operations. The net result is a system that supports the most complicated calculations yet on IBM's hardware, leaving the company optimistic that its users will find some calculations where quantum hardware provides an advantage.

Better hardware and software

IBM's early efforts in the quantum computing space saw it ramp up the qubit count rapidly, being one of the first companies to reach the 1,000 qubit count. However, each of those qubits had an error rate that ensured that any algorithms that tried to use all of these qubits in a single calculation would inevitably trigger one. Since then, the company's focus has been on improving the performance of smaller processors. Wednesday's announcement was based on the introduction of the second version of its Heron processor, which has 156 qubits (up from an earlier 133 in Revision 1). That's still beyond the capability of simulations on classical computers, should it be able to operate with sufficiently low errors.

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What makes baseball’s “magic mud” so special?

7 November 2024 at 17:07

Since the 1940s, baseball players have been spreading a special kind of "magic mud" on new baseballs to reduce the slick, glossy shine and give pitchers a firmer grip. Now, scientists at the University of Pennsylvania have identified just what gives that magic mud its special properties, according to a new paper published in the Proceedings of the National Academy of Sciences.

Before magic mud came along, baseballs were treated with a mix of water and soil from the infield or, alternatively, tobacco juice or shoe polish. But these substances stained and scratched up the ball's leather surface. Lena Blackburne was a third-base coach for the Philadelphia Athletics in the 1930s when an umpire complained about that, so he hunted for a better mud. Blackburne found that mud in a still-secret location purportedly near Palmyra, New Jersey, and a baseball dynasty was born: Lena Blackburne Baseball Rubbing Mud. Once harvested, the mud is strained, skimmed of excess water, rinsed with tap water, and then subjected to a secret "proprietary treatment" before being allowed to settle.

Yet there hasn't been much scientific research on the magic mud apart from one 2022 study. We do know quite a bit about the complex behavior of soil in general, including mud. Per the authors, mud is essentially "a dense suspension of predominantly clay and silt particles in water," sometimes with a bit of sand in the mix, although this has little effect on how mud behaves under shearing forces (rheology). Technically, it falls into the non-Newtonian fluid category, in which the viscosity changes (either thickening or thinning) in response to an applied strain or shearing force, thereby straddling the boundary between liquid and solid behavior.

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© S. Pradeep et al., 2024

Researchers spot black hole feeding at 40x its theoretical limit

4 November 2024 at 21:21

How did supermassive black holes end up at the center of every galaxy? A while back, it wasn't that hard to explain: That's where the highest concentration of matter is, and the black holes had billions of years to feed on it. But as we've looked ever deeper into the Universe's history, we keep finding supermassive black holes, which shortens the timeline for their formation. Rather than making a leisurely meal of nearby matter, these black holes have gorged themselves in a feeding frenzy.

With the advent of the Webb Space Telescope, the problem has pushed up against theoretical limits. The matter falling into a black hole generates radiation, with faster feeding meaning more radiation. And that radiation can drive off nearby matter, choking off the black hole's food supply. That sets a limit on how fast black holes can grow unless matter is somehow fed directly into them. The Webb was used to identify early supermassive black holes that needed to have been pushing against the limit for their entire existence.

But the Webb may have just identified a solution to the dilemma as well. It has spotted a black hole that appears to have been feeding at 40 times the theoretical limit for millions of years, allowing growth at a pace sufficient to build a supermassive black hole.

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For the strongest disc golf throws, it’s all in the thumbs

23 October 2024 at 21:15

When Zachary Lindsey, a physicist at Berry College in Georgia, decided to run an experiment on how to get the best speed and torque while playing disc golf (aka Frisbee golf), he had no trouble recruiting 24 eager participants keen on finding science-based tips on how to improve their game. Lindsey and his team determined the optimal thumb distance from the center of the disc to increase launch speed and distance, according to a new paper published in the journal AIP Advances.

Disc golf first emerged in the 1960s, but "Steady" Ed Hendrick, inventor of the modern Frisbee, is widely considered the "father" of the sport since it was he who coined and trademarked the name "disc golf" in 1975. He and his son founded their own company to manufacture the equipment used in the game. As of 2023, the Professional Disc Golf Association (PDGA) had over 107,000 registered members worldwide, with players hailing from 40 countries.

A disc golf course typically has either nine or 18 holes or targets, called "baskets." There is a tee position for starting play, and players take turns throwing discs until they catch them in the basket, similar to how golfers work toward sinking a golf ball into a hole. The expected number of throws required of an experienced player to make the basket is considered "par."

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What do planet formation and badminton have in common?

15 October 2024 at 15:51

The birth of a planet starts with a microscopic grain floating in a protoplanetary disk, a swirling cloud of gas and other particles surrounding a young star. How the gas and dust interact has implications for the formation of new worlds.

“Those teeny grains—those are the building blocks of planets,” said Zhe-Yu Daniel Lin, an astrophysicist at the Carnegie Institution for Science. He describes the shape of the grains as “potatoes.”

It’s hot and breezy in the interstellar cloud, but it's not entirely chaotic. Astronomical observations have found that the grains, instead of tumbling through space, are oriented neatly along their orbital trajectories. To explain how the grains float in formation, new research led by Lin leans on the working principle behind an Earthly object: the badminton shuttle.

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Black hole jet appears to boost rate of nova explosions

27 September 2024 at 20:29

The intense electromagnetic environment near a black hole can accelerate particles to a large fraction of the speed of light and sends the speeding particles along jets that extend from each of the object's poles. In the case of the supermassive black holes found in the center of galaxies, these jets are truly colossal, blasting material not just out of the galaxy, but possibly out of the galaxy's entire neighborhood.

But this week, scientists have described how the jets may be doing some strange things inside of a galaxy, as well. A study of the galaxy M87 showed that nova explosions appear to be occurring at an unusual high frequency in the neighborhood of one of the jets from the galaxy's central black hole. But there's absolutely no mechanism to explain why this might happen, and there's no sign that it's happening at the jet that's traveling in the opposite direction.

Whether this effect is real, and whether we can come up with an explanation for it, may take some further observations.

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These 3D-printed pipes inspired by shark intestines outperform Tesla valves

26 September 2024 at 17:52

Scientists at the University of Washington have re-created the distinctive spiral shapes of shark intestines in 3D-printed pipes in order to study the unique fluid flow inside the spirals. Their prototypes kept fluids flowing in one preferred direction with no need for flaps to control that flow and performed significantly better than so-called "Tesla valves," particularly when made of soft polymers, according to a new paper published in the Proceedings of the National Academy of Sciences.

As we've reported previously, in 1920, Serbian-born inventor Nikola Tesla designed and patented what he called a "valvular conduit": a pipe whose internal design ensures that fluid will flow in one preferred direction, with no need for moving parts, making it ideal for microfluidics applications, among other uses. The key to Tesla's ingenious valve design is a set of interconnected, asymmetric, tear-shaped loops.

In his patent application, Tesla described this series of 11 flow-control segments as being made of "enlargements, recessions, projections, baffles, or buckets which, while offering virtually no resistance to the passage of fluid in one direction, other than surface friction, constitute an almost impassable barrier to its flow in the opposite direction." And because it achieves this with no moving parts, a Tesla valve is much more resistant to the wear and tear of frequent operation.

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Tailwinds don’t help “everesting” cyclists

25 September 2024 at 16:05
man in bicycle in cycling shorts and helmet

Enlarge / Physicist Martin Bier in an aerodynamic tuck, a cycling position that reduces wind resistance. (credit: Martin Bier)

Many avid bicyclists these days have hopped onto the "everesting" bandwagon, in which one rides up and down the same mountain route over and over until the total distance of one's ascents matches the elevation of Mount Everest: 8,848 meters or about 5.5 miles. Recently there has been debate over whether a strong tailwind could help a rider improve their time. But apparently that's not the case, according to a new paper published in the American Journal of Physics by physicist Martin Bier of East Carolina University in North Carolina.

The term "everesting" takes its name from George Mallory, grandson of the legendary 1920s mountaineer George Mallory who participated in the first three British Everest expeditions. Mallory the younger was prepping for his Everest attempt in 1994, and his training included weekend workouts involving bicycling up Mount Donna Buang in Australia many times until he had achieved the elevation of Mount Everest.

Twenty years later, another Australian cycling enthusiast, Andy van Bergen, started organizing worldwide "everesting" events. Participating cyclists would pick a hill near their homes and track each other's progress online. The events became extremely popular in 2020 after the outbreak of the COVID-19 pandemic sparked global lockdowns.

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Researchers spot largest black hole jets ever discovered

18 September 2024 at 16:57
Image of a faint web of lighter material against a dark background. The web is punctuated by bright objects, representing galaxies. One of those galaxies has shot jets of material outside the web itself.

Enlarge / Artist's conception of a dark matter filament containing a galaxy with large jets. (Caltech noted that some details of this image were created using AI.) (credit: Martijn Oei (Caltech) / Dylan Nelson (IllustrisTNG Collaboration).)

The supermassive black holes that sit at the center of galaxies aren't just decorative. The intense radiation they emit when feeding helps drive away gas and dust that would otherwise form stars, providing feedback that limits the growth of the galaxy. But their influence may extend beyond the galaxy they inhabit. Many black holes produce jets and, in the case of supermassive versions, these jets can eject material entirely out of the galaxy.

Now, researchers are getting a clearer picture of just how far outside of the galaxy their influence can reach. A new study describes the largest-ever jets observed, extending across a total distance of 23 million light-years (seven megaparsecs). At those distances, the jets could easily send material into other galaxies and across the cosmic web of dark matter that structures the Universe.

Extreme jets

Jets are formed in the complex environment near a black hole. The intense heating of infalling material ionizes and heats it, creating electromagnetic fields that act as a natural particle accelerator. This creates jets of particles that travel at a substantial fraction of the speed of light. These will ultimately slam into nearby material, creating shockwaves that heat and accelerate that, too. Over time, this leads to large-scale, coordinated outflows of material, with the scale of the jet being proportional to a combination of the size of the black hole and the amount of material it is feeding on.

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Physicists discover “hidden turbulence” throughout van Gogh’s Starry Night

17 September 2024 at 15:10
image of van gogh's painting of the night sky rendered in dark blue with swirling yellows indicating stars and wind blowing

Enlarge / Many have seen a reflection of Vincent van Gogh's inner turmoil in the swirling vortices of The Starry Night. (credit: Public doman)

Vincent van Gogh's most famous painting is The Starry Night (1889), created (along with several other masterpieces) during the artist's stay at an asylum in Arles following his breakdown in December 1888. Where some have seen the swirling vortices of the night sky depicted in Starry Night as a reflection of van Gogh's own inner turmoil, physicists often see a masterful depiction of atmospheric turbulence. According to a new paper published in the journal Physics of Fluids, the illusion of movement in van Gogh's blue sky is also due to the scale of the paint strokes—a second kind of "hidden turbulence" at the microscale that diffuses throughout the entire canvas.

“It reveals a deep and intuitive understanding of natural phenomena,” said co-author Yongxiang Huang of Xiamen University in China. “Van Gogh’s precise representation of turbulence might be from studying the movement of clouds and the atmosphere or an innate sense of how to capture the dynamism of the sky.”

Physicists have long been fascinated by van Gogh's innate feel for turbulence. As previously reported, in a 2014 TED-Ed talk, Natalya St. Clair, a research associate at the Concord Consortium and coauthor of The Art of Mental Calculation, used Starry Night to illuminate the concept of turbulence in a flowing fluid. In particular, she talked about how van Gogh's technique allowed him (and other Impressionist painters) to represent the movement of light across water or in the twinkling of stars. We see this as a kind of shimmering effect, because the eye is more sensitive to changes in the intensity of light (a property called luminance) than to changes in color.

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Teenage Maurice Sendak illustrated his teacher’s 1947 pop-sci book

27 August 2024 at 17:58
A young Maurice Sendak’s illustration of two possible outcomes of atomic power.

Enlarge / A young Maurice Sendak’s illustration of two possible outcomes of atomic power for the 1947 pop-sci book Atomics for the Millions. (credit: McGraw Hill/Public domain)

Beloved American children's author and illustrator Maurice Sendak probably needs no introduction. His 1963 book, Where the Wild Things Are, is an all-time classic in the picture genre that has delighted generations of kids. It has sold over 19 million copies worldwide, won countless awards, and inspired a children's opera and a critically acclaimed 2009 feature film adaptation, as well as being spoofed on an episode of The Simpsons.

But one might be surprised to learn (as we were) that a teenage Sendak published his first professional illustrations in a 1947 popular science book about nuclear physics, co-authored by his high school physics teacher: Atomics for the Millions. Science historian Ryan Dahn came across a copy in the Niels Bohr Library & Archives at the American Institute of Physics in College Park, Maryland, and wrote a short online article about the book for Physics Today, complete with scans of Sendak's most striking illustrations.

Born in Brooklyn to Polish-Jewish parents, Sendak acknowledged that his childhood had been a sad one, overshadowed by losing many extended family members during the Holocaust. That, combined with health issues that confined him to his bed, compelled the young Sendak to find solace in books. When Sendak was 12, he watched Walt Disney's Fantasia, which inspired him to become an illustrator.

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Hydrogels can learn to play Pong

22 August 2024 at 18:32
This electroactive polymer hydrogel "learned" to play Pong. Credit: Cell Reports Physical Science/Strong et al.

Pong will always hold a special place in the history of gaming as one of the earliest arcade video games. Introduced in 1972, it was a table tennis game featuring very simple graphics and gameplay. In fact, it's simple enough that even non-living materials known as hydrogels can "learn" to play the game by "remembering" previous patterns of electrical stimulation, according to a new paper published in the journal Cell Reports Physical Science.

"Our research shows that even very simple materials can exhibit complex, adaptive behaviors typically associated with living systems or sophisticated AI," said co-author Yoshikatsu Hayashi, a biomedical engineer at the University of Reading in the UK. "This opens up exciting possibilities for developing new types of 'smart' materials that can learn and adapt to their environment."

Hydrogels are soft, flexible biphasic materials that swell but do not dissolve in water. So a hydrogel may contain a large amount of water but still maintain its shape, making it useful for a wide range of applications. Perhaps the best-known use is soft contact lenses, but various kinds of hydrogels are also used in breast implants, disposable diapers, EEG and ECG medical electrodes, glucose biosensors, encapsulating quantum dots, solar-powered water purification, cell cultures, tissue engineering scaffolds, water gel explosives, actuators for soft robotics, supersonic shock-absorbing materials, and sustained-release drug delivery systems, among other uses.

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Astronomers think they’ve found a plausible explanation of the Wow! signal

21 August 2024 at 20:14
The Wow! signal represented as

Enlarge / The Wow! signal, represented as "6EQUJ5," was discovered in 1977 by astronomer Jerry Ehman. (credit: Public domain)

An unusually bright burst of radio waves—dubbed the Wow! signal—discovered in the 1970s has baffled astronomers ever since, given the tantalizing possibility that it just might be from an alien civilization trying to communicate with us. A team of astronomers think they might have a better explanation, according to a preprint posted to the physics arXiv: clouds of atomic hydrogen that essentially act like a naturally occurring galactic maser, emitting a beam of intense microwave radiation when zapped by a flare from a passing magnetar.

As previously reported, the Wow! signal was detected on August 18, 1977, by The Ohio State University Radio Observatory, known as “Big Ear.” Astronomy professor Jerry Ehman was analyzing Big Ear data in the form of printouts that, to the untrained eye, looked like someone had simply smashed the number row of a typewriter with a preference for lower digits. Numbers and letters in the Big Ear data indicated, essentially, the intensity of the electromagnetic signal picked up by the telescope over time, starting at ones and moving up to letters in the double digits (A was 10, B was 11, and so on). Most of the page was covered in ones and twos, with a stray six or seven sprinkled in.

But that day, Ehman found an anomaly: 6EQUJ5 (sometimes misinterpreted as a message encoded in the radio signal). This signal had started out at an intensity of six—already an outlier on the page—climbed to E, then Q, peaked at U—the highest power signal Big Ear had ever seen—then decreased again. Ehman circled the sequence in red pen and wrote “Wow!” next to it. The signal appeared to be coming from the direction of the Sagittarius constellation, and the entire signal lasted for about 72 seconds. Alas, SETI researchers have never been able to detect the so-called “Wow! Signal” again, despite many tries with radio telescopes around the world.

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Rocket Lab entered “hero mode” to finish Mars probes—now it’s up to Blue Origin

19 August 2024 at 17:16
The two spacecraft for NASA's ESCAPADE mission at Rocket Lab's factory in Long Beach, California.

Enlarge / The two spacecraft for NASA's ESCAPADE mission at Rocket Lab's factory in Long Beach, California. (credit: Rocket Lab)

Two NASA spacecraft built by Rocket Lab are on the road from California to Florida this weekend to begin preparations for launch on Blue Origin's first New Glenn rocket.

These two science probes must launch between late September and mid-October to take advantage of a planetary alignment between Earth and Mars that only happens once every 26 months. NASA tapped Blue Origin, Jeff Bezos' space company, to launch the Escape and Plasma Acceleration and Dynamics Explorers (ESCAPADE) mission with a $20 million contract.

Last November, the space agency confirmed the $79 million ESCAPADE mission will launch on the inaugural flight of Blue Origin's New Glenn rocket. With this piece of information, the opaque schedule for Blue Origin's long-delayed first New Glenn mission suddenly became more clear.

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Why cricket’s latest bowling technique is so effective against batters

13 August 2024 at 19:24
Some cricket bowlers favor keeping the arm horizontal during delivery, the better to trick the batsmen.

Enlarge / Some cricket bowlers favor keeping the arm horizontal during delivery, the better to trick the batsmen. (credit: Rae Allen/CC BY 2.0)

Although the sport of cricket has been around for centuries in some form, the game strategy continues to evolve in the 21st century. Among the newer strategies employed by "bowlers"—the equivalent of the pitcher in baseball—is delivering the ball with the arm horizontally positioned close to the shoulder line, which has proven remarkably effective in "tricking" batsmen in their perception of the ball's trajectory.

Scientists at Amity University Dubai in the United Arab Emirates were curious about the effectiveness of the approach, so they tested the aerodynamics of cricket balls in wind tunnel experiments. The team concluded that this style of bowling creates a high-speed spinning effect that shifts the ball's trajectory mid-flight—an effect also seen in certain baseball pitches, according to a new paper published in the journal Physics of Fluids.

“The unique and unorthodox bowling styles demonstrated by cricketers have drawn significant attention, particularly emphasizing their proficiency with a new ball in early stages of a match,” said co-author Kizhakkelan Sudhakaran Siddharth, a mechanical engineer at Amity University Dubai. “Their bowling techniques frequently deceive batsmen, rendering these bowlers effective throughout all phases of a match in almost all formats of the game.”

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Studying the skin of the great white shark could help reduce drag in aircraft

12 August 2024 at 21:09
Great white shark at Isla Guadalupe, Mexico

Enlarge / Great white sharks can reduce drag at different swimming speeds thanks to high and low ridged denticles in its skin. (credit: Terry Goss/CC BY 2.5)

The great white shark (Carcharodon carcharias) is a swift and mighty hunter, capable of reaching speeds as high as 6.7 m/s when breaching, although it prefers to swim at slower speeds for migration and while waiting for prey. A team of Japanese researchers has studied the structure of the great white's skin to learn more about how these creatures adapt so well to a wide range of speeds. Their findings could lead to more efficient aircraft and boats with greatly reduced drag, according to a recent paper published in the Journal of the Royal Society Interface.

As previously reported, anyone who has touched a shark knows the skin feels smooth if you stroke from nose to tail. Reverse the direction, however, and it feels like sandpaper. That's because of tiny translucent scales, roughly 0.2 millimeters in size, called "denticles" (because they strongly resemble teeth) all over the shark's body, especially concentrated in the animal's flanks and fins. It's like a suit of armor for sharks, and it also serves as a means of reducing drag in the water while swimming.

Pressure drag is the result of flow separation around an object, like an aircraft or the body of a mako shark as it moves through water; the magnitude of pressure drag is determined by the shape of the object. It's what happens when the fluid flow separates from the surface of an object, forming eddies and vortices that impede the object's movement. Since the shark's body is constantly undulating as it swims, it needs something to help keep the flow attached around that body to reduce that drag. Denticles serve that purpose.

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