Events in China involving US actor Will Smith's son Jaden Smith set for Friday to Sunday were delayed after the rapper was accused of making racist comments about China. Refunds for the events are currently being carried out.

A post on Chinese lifestyle app Xiaohongshu has taken over Chinese social media. The post claims that a Chinese netizen was traveling on a high-speed train from Kyoto to Tokyo in Japan on August 19, and happened to be in the same cabin with Smith and his team. 

"Someone asked Jaden his opinion on different countries including China. Jaden replied with 'F*** China.' Smith repeatedly made derogatory remarks about China," the post wrote. 

The post on Xiaohongshu said that Smith and his team were drinking, laughing, banging the tray table and making these offensive comments very loudly. The train attendants and someone who appeared to be a passenger had to talk to the crowd several times to get them to lower their voices. The lot didn't seem to care despite other people's dissatisfaction.

The witness also posted photos and a video of Smith and his team on the train. "Unfortunately, I wasn't able to capture their offensive comments in the video," the post read.  

While some fans posted pictures showing themselves unfollowing Smith on social media to express their disappointment and anger toward his alleged remarks, comments flooded his Instagram page, urging him to give a further explanation or apology. The rapper didn't respond, instead comments for his recent posts were turned off. An Instagram story announcing that his events in China would be rescheduled was also posted. 

"Rescheduled dates will be announced soon," he wrote.   

The rapper was originally scheduled to perform in Beijing, Shanghai and Shenzhen on Friday to Sunday. On Wednesday the event organizer in China announced that refunds would be issued within five to seven business days.   

On Chinese social media platform Sina Weibo, the hashtag related to Jaden Smith has reached more than 466,000 views.

Some fans noted that there was no actual proof that the rapper made any racist comments and that the original post was just a one sided story. They called for the witness to provide more concrete proof.

Searching for the witness on Xiaohongshu on Sunday, the Global Times could not find the original user.  

Some argued that if he hadn't made up his story, he would have clarified the misunderstanding. 

This post was particularly shocking to Chinese netizens, given the Smith family's historically positive ties with China. Will Smith, Jaden's father, has maintained accounts on major Chinese social platforms and has also endorsed many Chinese products in the past. His popularity among Chinese audiences is evident. Notably, he and a young Jaden's performance in the movie The Pursuit of Happynes is much beloved by Chinese fans.

Jaden himself isn't a stranger to China either. As a child actor, he worked alongside Hong Kong action movie superstar Jackie Chan in the remake of The Karate Kid. As an adult and a musician, he's visited the country multiple times. 

The question on many minds is: Why would someone, who's repeatedly visited a country for work and seemingly built connections there, risk damaging those ties with derogatory comments? And who continues to provide such figures with platforms and opportunities despite repeated controversies?

There's a broader lesson here about the importance of cultural sensitivity, especially for global celebrities. A casual comment can quickly spiral into a major incident with far-reaching implications, said a commentator. 

In an age of instant information and constant connectivity, celebrities need to be more cautious than ever. And as audiences, perhaps we ought to think more critically about the figures we choose to support.

The total number of internet users in China has reached 1.079 billion, with internet usage increasing to 76 percent, according to a new report released on Monday. Observers said China's digital infrastructure, especially generative artificial intelligence (AI), is greatly empowering the country's economic and social development.

The number of internet users as of June 2023 saw an increase of 11.09 million compared to December 2022, according to the Report on China's Internet Development by the China Internet Network Information Center (CNNIC) on Monday. Also, a total of 2.937 million 5G base stations have been constructed and put into use.

The report showed almost all Chinese internet users are video users, with the number of network video users reaching 1.044 billion, an increase of 13.8 million from December 2022. 

About 82 percent of net users are purchasing online, with the number reaching 884 million, an increase of 38.8 million from December 2022, according to the report.

Observers said the fact that internet usage in China has increased to 76 percent shows that the country's digital infrastructure has entered a phase of rapid development and is likely to continue growing at a fast pace. Some mentioned that promoting internet usage in China's rural villages could offer a new growth point. 

By organizing events such as the Village Basketball Association, counties in Southwest China's Guizhou Province are setting an example for Chinese rural areas about how to use China's mature infrastructure and social media networks to connect with the outside world, which can also generate huge economic benefits.

Mao Li, vice chairman of the China Internet Association, believes that against the backdrop of gradual recovery in the first half of the year, the digital economy has become an important engine for stable growth.

The report said that since the end of the COVID-19 pandemic, Chinese internet companies such as online retailers, ride-hailing services, and online travel firms, have seized the favorable market conditions and consolidated strong development momentum.

As of June, the user base for online shopping, ride-hailing services, and online travel bookings in China increased by over 30 million people, compared to the data for December 2022. 

In the first half of the year, the national online retail sales reached 7.16 trillion yuan, up 13.1 percent year-on-year, with rural online retail sales amounting to 1.12 trillion yuan, the CNNIC report said. 

The report said that as of June, China has built and put into operation of a total of 2.937 million 5G base stations, with 676 million 5G mobile phone users. 5G applications have also been integrated into 60 major economic sectors, accelerating their expansion into key areas such as healthcare, education, and transport. 

Zhang Hui, vice dean of the School of Economics at Peking University, told the Global Times the rapid construction of digital infrastructure in the first half of 2023 helps to accelerate economic and social development.

In addition, the CNNIC report said the accumulated mobile internet traffic has reached 142.3 billion GB, up 14.6 percent year-on-year. Mobile internet applications have flourished, with a monitored total of 2.6 million active apps in the domestic market, further covering the daily learning, work, and lifestyle needs of internet users.

Wang Changqing, a research fellow from the CNNIC, noted that generative AI techniques have been flourishing in the first half of 2023, which has injected increased vitality into the digital industrial environment. Along with the push to develop generative AI products, China has also rushed to integrate AI with the manufacturing industry, with more than 2,500 digital and intelligent workshops and factories built across the country so far, Wang noted. 

A wandering baby Jupiter could help explain why there are no planets closer to the sun than Mercury and why the innermost planet is so tiny, a new study suggests.

Jupiter’s core might have formed close to the sun and then meandered through the rocky planet construction zone. As the infant Jupiter moved, it would have absorbed some planet-building material while kicking out the rest. This would have starved the inner planets — Mercury, Venus, Earth and Mars — of raw materials, keeping them small and preventing any other planets from forming close to the sun, say planetary scientist Sean Raymond and colleagues online March 5 in Monthly Notices of the Royal Astronomical Society.
“When I first came up with it, I thought it was ridiculous,” says Raymond, of the Laboratory of Astrophysics of Bordeaux in Floirac, France. “This model is kind of crazy, but it holds up.”

Rocky planets snuggled up to their suns are common in our galaxy. Many systems discovered by NASA’s Kepler space telescope have multiple planets — several larger than Earth — crammed into orbits smaller than Mercury’s. Though Kepler is biased toward finding scrunched-up solar systems, researchers wonder why there is a large gap between the sun and Mercury.

Scientists suspect that the inner planets of our solar system formed 4.6 billion years ago from a belt of debris that stretched between the current orbits of Venus and Earth. Mercury and Mars were built out of material along the edges of this belt, which explains why they are relatively small. Jupiter, traditionally thought to have formed much farther out, gets the blame for creating the belt’s outer edge. What shaped the inner edge has remained difficult to explain (SN Online: 3/23/15).

Raymond and colleagues ran computer simulations to see what would happen to the inner solar system if a body with three times the mass of Earth started inside Mercury’s orbit and then migrated away from the sun. They found that if the interloper didn’t move too fast or too slow, it would sweep clean the innermost parts of the disk of gas and dust that encircled the young sun and leave just enough material to form the rocky planets.

Raymond and colleagues also discovered that young Jupiter could have corralled enough debris to form a second core — one that got nudged away from the sun as Jupiter migrated. This second core could be the seed from which Saturn grew, the researchers suggest. Jupiter’s gravity could have dragged debris to the asteroid belt, too. Raymond says that might explain the origin of iron meteorites, which some researchers argue should have formed relatively close to the sun.
Jupiter plowing through the inner solar system sounds plausible, says Sourav Chatterjee, an astrophysicist at Northwestern University in Evanston, Ill. “But there are several ways this can go wrong.”

Building a giant planet core inside the orbit of Mercury is not hard, he says. Pebbles and boulders in the nascent solar system probably drifted inward. They could have piled up close to the sun where solar magnetic fields created turbulence that trapped infalling material. If just a fraction of this debris stuck together, a rocky orb a few times as massive as Earth could form.

Having proto-Jupiter wander to the outer solar system, however, is asking a lot, says Chatterjee. Gravitational interactions with spiral waves in the disk that surrounded the sun can propel a newborn planet either inward or outward. But how fast, how far and in which direction the planet travels depends on properties such as disk temperature and density, which Raymond and colleagues readily acknowledge. Their simulations assume and simplify disk characteristics to see if building the solar system inside-out is even plausible.

“We’re building up a logical chain that shows [this idea] is not completely crazy,” Raymond says. “We’re not saying it happened. Just if it happened, what would it do?”

Scientists have built a bacterium that contains the minimal genetic ingredients needed for free living.

This bacterium’s entire set of genetic blueprints, its genome, consists of only 473 genes, including 149 whose precise biological function is unknown, researchers report in the March 25 Science.

The newly-created bacterium contains a minimalist version of the genome of Mycoplasma mycoides. Mycoplasma already have some of the smallest known genomes. M. mycoides used in the experiments started with 901 genes. In comparison, other bacteria, including E. coli, may have 4,000 to 5,000 genes. Humans have more than 22,000 genes, although not all are necessary (SN: 4/2/16, p. 18).
In 2010, researchers at the J. Craig Venter Institute in La Jolla, Calif., replicated the entire genome of M. mycoides and popped it into a cell of a different species, Mycoplasma capricolum, creating what some people called the first synthetic organism (SN: 6/19/10, p. 5). The new work strips the M. mycoides genome down to its essential elements before transplanting it to the M. capricolum shell, producing a minimal bacteria dubbed syn3.0.

Researchers hope syn3.0’s uncluttered genome will teach them more about the basics of biology. Such minimal genome bacteria also may be chassis on which to build custom-made microbes for producing drugs or chemicals.
J. Craig Venter, founder of the nonprofit institute, and a team of researchers there led by Clyde Hutchison III and Daniel Gibson initially set out to design an organism based on a core set of about 300 genes that researchers surmised a microbe would need to survive on its own. But when the researchers tried to bring their computer creations to life, “every one of our designs failed,” Venter said in teleconference with reporters. The failure was due to leaving genes of unknown function out of the mix. About 32 percent of the genetic ingredients ultimately needed to cook up even a simple organism were left out of the initial recipe because the researchers didn’t know what the genes did and didn’t understand their importance. Once those genes were mixed back into the batter, the bacteria sprung to life.

“I think we’re showing how complex life is in even the simplest of organisms,” Venter said. “These findings are very humbling” because they show that researchers still don’t fully understand even the minimal requirements for life.

That lack of knowledge is “frustrating after so many years of molecular biology,” says synthetic biologist Pamela Silver of Harvard Medical School. But the pared-down microbe may be a good platform for discovering what genes of unknown function do, she says.

Other researchers have attempted to make minimal genomes by stripping away one gene at a time. But the Venter group built their lean microbe from the ground up, synthesizing pieces of DNA that would later be stitched into a complete genome.

Drew Endy, a synthetic biologist at Stanford University, is among several scientists applauding the made-from-scratch approach. “Only when you try to build something do you find out what’s truly required. Too often in biology we end up with only data, a computer model, or a just-so story. When you actually try to build something, you can’t hide from your ignorance,” Endy said in an e-mail. “What you build either works or it doesn’t.”

At first, the bare-bones genome didn’t work. Some genes that appeared to be nonessential for life are really requirements, the researchers discovered. Those genes tended to have redundant functions with another gene. Researchers could remove one of those genes, but not both at the same time, just as knocking out one engine on a twin-engine jet will keep the plane airborne, but disabling both engines will lead to a crash, says Gibson.

Although syn3.0’s genome is far smaller than those of other free-living bacteria, it may not be the minimal genome for every independent organism in every situation. (Symbiotic bacteria living inside host cells may have fewer genes than syn3.0 does, but cannot survive on their own.) Other researchers have theorized that a minimal cell could consist of one single RNA-replicating gene inside a membrane, says geneticist George Church of Harvard University.

Starting with another organism or growing the bacteria under different conditions would probably lead to a microbe with a different minimal set of genes, says Jay Keasling, a synthetic biologist at the University of California, Berkeley. “The minimal genome is in the eye of the beholder,” he says.

Gibson and Venter agree that they have created a minimal genome, but not necessarily the minimal genome. Syn3.0 is streamlined, but still contains a few frills. The team kept several “quasi-essential” genes that aren’t strictly necessary for life, but allow the bacteria to grow fast enough to make them useful in the lab.

The last of a group of dense minerals that make up much of Earth’s crust and upper mantle has been found tucked inside a meteorite that slammed into Australia 135 years ago. The newly discovered mineral, a variety of majorite, is potentially abundant in sinking tectonic plates and could help illuminate the behavior of the deep Earth, its discoverers say.

Each identical component of this mineral contains 32 magnesium atoms, 32 silicon atoms and 96 oxygen atoms arranged in a distorted cube. Natural samples of MgSiO3 tetragonal garnet, the mineral’s scientific moniker, had eluded scientists since the mineral was first artificially produced in 1985.
Naotaka Tomioka, a mineralogist at the Kochi Institute for Core Sample Research in Japan, and colleagues discovered 0.5-micrometer-wide grains of the mineral in a slice of the 19th century meteorite. While many minerals found in meteorites form when slamming into Earth, the new mineral formed in space when two asteroids collided at a relative speed of about 2 kilometers per second, the researchers report online March 25 in Science Advances.

One challenge remains for the researchers: As discoverers of the mineral, they now get to name it.

Financial health takes a hit among people who smoke a lot of marijuana from adolescence into young adulthood, even if they don’t get hooked on the drug, researchers say.

The more years that individuals smoke pot four or more days a week, the more likely they are to experience serious money problems, say social epidemiologist Magdalena Cerdá of the University of California, Davis and her colleagues. Cash woes include defaulting on credit card payments, struggling to pay for food and rent and going on welfare.
In a representative sample of 947 New Zealanders studied from birth to age 38, adult economic and social problems — which also include a fall from middle-class status, stealing money at work and domestic violence — occurred about equally among regular marijuana and alcohol users, the scientists report March 22 in Clinical Psychological Science. Of 29 persistent pot smokers who grew up in middle-class families, 15 experienced downward social mobility, versus only 23 of 160 middle-class peers who never used marijuana.

Participants who consistently qualified as dependent on marijuana after age 18 encountered the worst money troubles over time, even exceeding those of alcoholic peers.

These findings don’t prove that regular pot smoking caused Kiwis’ financial difficulties, the investigators caution. But the association between marijuana and money troubles remained after accounting for childhood poverty, IQ, teenage delinquency and depression, impulsiveness, self-reported motivation to succeed in life, pot-related criminal convictions and abuse of alcohol and other drugs on top of frequent marijuana use.

Thousands of national parks have been established around the world to preserve wildlife. But towns, farms, ranches and roads have grown up around many of these parks, creating islands of wilderness in a sea of humanity. If the creatures inside are to thrive, they need ways to travel between the islands, contends “Wild Ways,” a new documentary from the TV series NOVA.

Isolation can be especially troublesome for large predators, such as lions, that live alone or in small groups. In some areas of Africa, lions can move between populations to avoid inbreeding. But some lions, such as the few in Tanzania’s Ngorongoro Crater, are cut off from other groups. In such populations, cubs are born smaller, die younger and are more susceptible to disease. And drought or overhunting could easily wipe them out, the show notes.
To connect these smaller populations, conservationists are now building wildlife corridors between parks. One of the most ambitious projects is the Yellowstone to Yukon Conservation Initiative, which aims to create connections between grizzly bears in the Canadian Arctic and the western United States. Other large wildlife corridors are being planned in Central America, eastern Australia and the Himalayas. But there are often roadblocks. It can be difficult to persuade people to spend money on wildlife, and it can be even harder when those animals kill livestock or humans.

“It is important that we provide incentives for local communities, in particular, who should now look at wildlife as some form of economic asset to themselves,” says Simon Munthali of the Kavango-Zambezi Transfrontier Conservation Area, which is attempting to connect parks in five countries across southern Africa. With the right incentives, people will be more accepting of wildlife moving across land and may even benefit from it, he says in the documentary. Botswana, for instance, has developed a large ecotourism industry that provides jobs and money for local people, motivating animal protection.

The documentary is a bit too optimistic about the removal of hurdles that stand in the path of wildlife corridors, especially in the American West, where there is ongoing debate about how to manage public lands. And then there is the question of whether these corridors can be created fast enough to save the world’s dwindling animal populations. But, as Michael Soulé, one of the founders of the field of conservation biology, says: “It’s our last chance to protect the diversity of life on Earth.” “Wild Ways” makes a convincing case that we should be willing to try.

Parasitic worms may hold the secret to soothing inflamed bowels.

In studies of mice and people, parasitic worms shifted the balance of bacteria in the intestines and calmed inflammation, researchers report online April 14 in Science. Learning how worms manipulate microbes and the immune system may help scientists devise ways to do the same without infecting people with parasites.

Previous research has indicated that worm infections can influence people’s fertility (SN Online: 11/19/15), as well as their susceptibility to other parasite infections (SN: 10/5/13, p. 17) and to allergies (SN: 1/29/11, p. 26). Inflammatory bowel diseases also are less common in parts of the world where many people are infected with parasitic worms.
P’ng Loke, a parasite immunologist at New York University School of Medicine, and colleagues explored how worms might protect against Crohn’s disease. The team studied mice with mutations in the Nod2 gene. Mutations in the human version of the gene are associated with Crohn’s in some people.

The mutant mice develop damage in their small intestines similar to that seen in some Crohn’s patients. Cells in the mice’s intestines don’t make much mucus, and more Bacteroides vulgatus bacteria grow in their intestines than in the guts of normal mice. Loke and colleagues previously discovered that having too much of that type of bacteria leads to inflammation that can damage the intestines.
In the new study, the researchers infected the mice with either a whipworm (Trichuris muris) or a corkscrew-shaped worm (Heligmosomoides polygyrus). Worm-infected mice made more mucus than uninfected mutant mice did. The parasitized mice also had less B. vulgatus and more bacteria from the Clostridiales family. Clostridiales bacteria may help protect against inflammation.
“Although we already knew that worms could alter the intestinal flora, they show that these types of changes can be very beneficial,” says Joel Weinstock, an immune parasitologist at Tufts University Medical Center in Boston.

Both the increased mucus and the shift in bacteria populations are due to what’s called the type 2 immune response, the researchers found. Worm infections trigger immune cells called T helper cells to release chemicals called interleukin-4 and interleukin-13. Those chemicals stimulate mucus production. The mucus then feeds the Clostridiales bacteria, allowing them to outcompete the Bacteroidales bacteria. It’s still unclear how the mucus encourages growth of one type of bacteria over another, Loke says.

Blocking interleukin-13 prevented the mucus production boost and the shift in bacteria mix, indicating that the worms work through the immune system. But giving interleukin-4 and interleukin-13 to uninfected mice could alter the mucus and bacterial balance without worms’ help, the researchers discovered.

Loke and colleagues also wanted to know if worms affect people’s gut microbes. So the researchers took fecal samples from people in Malaysia who were infected with parasitic worms.

After taking a deworming drug, the people had less Clostridiales and more Bacteriodales bacteria than before. That shift in bacteria was associated with a drop in the number of Trichuris trichiura whipworm eggs in the people’s feces, indicating that getting rid of worms may have negative consequences for some people.

Having data from humans is important because sometimes results in mice don’t hold up in people, says Aaron Blackwell, a human biologist at the University of California, Santa Barbara. “It’s nice to show that it’s consistent in humans.”

Worms probably do other things to limit inflammation as well, Weinstock says. If scientists can figure out what those things are, “studying these worms and how they do it may very well lead to the development of new drugs.”

Before anybody even had a computer, Claude Shannon figured out how to make computers worth having.

As an electrical engineering graduate student at MIT, Shannon played around with a “differential analyzer,” a crude forerunner to computers. But for his master’s thesis, he was more concerned with relays and switches in electrical circuits, the sorts of things found in telephone exchange networks. In 1937 he produced, in the words of mathematician Solomon Golomb, “one of the greatest master’s theses ever,” establishing the connection between symbolic logic and the math for describing such circuitry. Shannon’s math worked not just for telephone exchanges or other electrical devices, but for any circuits, including the electronic circuitry that in subsequent decades would make digital computers so powerful.

It’s now conveniently a good time to celebrate Shannon’s achievements, on the occasion of the centennial of his birth (April 30) in Petoskey, Michigan, in 1916. Based on the pervasive importance of computing in society today, it wouldn’t be crazy to call the time since then “Shannon’s Century.”

“It is no exaggeration,” wrote Golomb, “to refer to Claude Shannon as the ‘father of the information age,’ and his intellectual achievement as one of the greatest of the twentieth century.”

Shannon is most well-known for creating an entirely new scientific field — information theory — in a pair of papers published in 1948. His foundation for that work, though, was built a decade earlier, in his thesis. There he devised equations that represented the behavior of electrical circuitry. How a circuit behaves depends on the interactions of relays and switches that can connect (or not) one terminal to another. Shannon sought a “calculus” for mathematically representing a circuit’s connections, allowing scientists to be able to design circuits effectively for various tasks. (He provided examples of the circuit math for an electronic combination lock and some other devices.)

“Any circuit is represented by a set of equations, the terms of the equations corresponding to the various relays and switches in the circuit,” Shannon wrote. His calculus for manipulating those equations, he showed, “is exactly analogous to the calculus of propositions used in the symbolic study of logic.”

As an undergraduate math (and electrical engineering) major at the University of Michigan, Shannon had learned of 19th century mathematician George Boole’s work on representing logical statements by algebraic symbols. Boole devised a way to calculate logical conclusions about propositions using binary numbers; 1 represented a true proposition and 0 a false proposition. Shannon perceived an analogy between Boole’s logical propositions and the flow of current in electrical circuits. If the circuit plays the role of the proposition, then a false proposition (0) corresponds to a closed circuit; a true proposition (1) corresponds to an open circuit. More elaborate math showed how different circuit designs would correspond to addition or multiplication and other features, the basis of the “logic gates” designed into modern computer chips.

For his Ph.D. dissertation, Shannon analyzed the mathematics of genetics in populations, but that work wasn’t published. In 1941 he began working at Bell Labs; during World War II, he wrote an important (at the time secret) paper on cryptography, which required deeper consideration of how to quantify information. After the war he developed those ideas more fully, focusing on using his 1s and 0s, or bits, to show how much information could be sent through a communications channel and how to communicate it most efficiently and accurately.

In 1948, his two papers on those issues appeared in the Bell System Technical Journal. They soon were published, with an introductory chapter by Warren Weaver, in a book titled The Mathematical Theory of Communication. Today that book is regarded as the founding document of information theory.

For Shannon, communication was not about the message, or its meaning, but about how much information could be communicated in a message (through a given channel). At its most basic, communication is simply the reproduction of a message at some point remote from its point of origin. Such a message might have a “meaning,” but such meaning “is irrelevant to the engineering problem” of transferring the message from one point to another, Shannon asserted. “The significant aspect is that that actual message is one selected from a set of possible messages.” Information, Shannon decided, is a measure of how much a communication reduces the ignorance about which of those possible messages has been transmitted.

In a very simple communication system, if the only possible messages are “yes” and “no,” then each message (1 for yes, 0 for no) reduces your ignorance by half. By Shannon’s math, that corresponds to one bit of information. (He didn’t coin the term “bit” — short for binary digit — but his work established its meaning.) Now consider a more complicated situation — an unabridged English dictionary, which should contain roughly half a million words. One bit would correspond to a yes-or-no that the word is in the first half of the dictionary. That reduces ignorance, but not very much. Each additional bit would reduce the number of possible words by half. Specifying a single word from the dictionary (eliminating all the ignorance) would take about 19 bits. (This fact is useful for playing the game of 20 Questions — just keep asking about the secret word’s location in the dictionary.)

Shannon investigated much more complicated situations and devised theorems for calculating information quantity and how to communicate it efficiently in the presence of noise. His math remains central to almost all of modern digital technology. As electrical engineer Andrew Viterbi wrote in a Shannon eulogy, Shannon’s 1948 papers “established all the key parameters and limits for optimal compression and transmission of digital information.”

Beyond its practical uses, Shannon’s work later proved to have profound scientific significance. His math quantifying information in bits borrowed the equations expressing the second law of thermodynamics, in which the concept of entropy describes the probability of a system’s state. Probability applied to the ways in which a system’s parts could be arranged, it seemed, mirrored the probabilities involved in reducing ignorance about a possible message. Shannon, well aware of this connection, called his measure entropy as well. Eventually questions arose about whether Shannon’s entropy and thermodynamic entropy shared more than a name.

Shannon apparently wasn’t sure. He told one writer in 1979 that he thought the connection between his entropy and thermodynamics would “hold up in the long run” but hadn’t been sufficiently explored. But nowadays a deep conceptual link shows up not only between Shannon’s information theory and thermodynamics, but in fields as diverse as quantum mechanics, molecular biology and the physics of black holes.
Shannon’s understanding of information plays a central role, for instance, in explaining how the notorious Maxwell’s demon can’t violate thermodynamics’ second law. Much of that work is based on Landauer’s principle, the requirement that energy is expended when information is erased. In developing that principle, Rolf Landauer (an IBM physicist) was himself influenced both by Shannon’s work and the work of Sadi Carnot in discerning the second law in the early 19th century.

Something Shannon and Carnot had in common, Landauer once emphasized to me, was that both discovered mathematical restrictions on physical systems that were independent of the details of the system. In other words, Carnot’s limit on the efficiency of steam engines applied to any sort of engine, no matter what it was made of or how it was designed. Shannon’s principles specifying the limits on information compression and transmission apply no matter what technology is used to do the compressing or sending. (Although in Shannon’s case, Landauer added, certain conditions must be met.)

“They both find limits for what you can do which are independent of future inventions,” Landauer told me. That is, they have grasped something profound about reality that is not limited to a specific place or time or thing.

So it seems that Shannon saw deeply not only into the mathematics of circuits, but also into the workings of nature. Information theorist Thomas Cover once wrote that Shannon belongs “in the top handful of creative minds of the century.” Some of Shannon’s original theorems, Cover noted, were not actually proved rigorously. But over time, details in the sketchy proofs have been filled in and Shannon’s intuitive insights stand confirmed. “Shannon’s intuition,” Cover concluded, “must have been anchored in a deep and natural theoretical understanding.” And it seems likely that Shannon’s intuition will provide even more insights into nature in the century ahead.

A decent office scanner has beaten X-ray blasts from multimillion-dollar synchrotron setups in revealing how air bubbles kill plant leaves during drought.

Intricate fans and meshes of plant veins carrying water are “among the most important networks in biology,” says Timothy Brodribb of the University of Tasmania in Hobart, Australia. When drought weakens the water tension in veins, air from plant tissues bubbles in, killing leaves much as bubble embolisms and clots in blood vessels can kill human tissue. As climate change and population growth increase risks of water shortage, Brodribb and other researchers are delving into the details of what makes some plants more resistant than others to drought.
The high energy of X-rays destroys delicate leaf tissue. So, based on a chat with microfluidics specialist Philippe Marmottant of the French National Center for Scientific Research, Brodribb tried repeatedly scanning a leaf with a light source below it to reveal darkening lines as air bubbles shot through the veins. A microscope or scanner proved perfect. Tracked this way, an invasion of killer bubbles “looks like a lightning storm,” he says.

He was surprised to see that bigger veins, despite their robust looks, fail before tiny ones (blue indicates earliest failures; red, the latest), as seen in an oak leaf (lower right) and Pteris fern (top). And networks in ferns with simpler branching patterns, as in the Adiantum ferns at bottom left, crash quickly.

This system of visualizing plant plumbing gave better resolution than expensive and elaborate X-ray techniques had, Brodribb, Marmottant and Diane Bienaimé report online April 11 in the Proceedings of the National Academy of Sciences.