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Broken spheres
Dyson died in 2020 before any of his spheres could be found — although they are just one of a dozen ideas that bear his name.
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“As a young scientist, Dyson showed that three competing quantum theories were actually the same theory — he summarily ended the competition,” said William Press, the Leslie Surginer Professor of Computer Science and Integrative Biology at the University of Texas at Austin. He was not involved in the study. “Later, he applied his genius to areas of astronomy, cosmology, the extraterrestrial realm, and also the very real problem of nuclear proliferation here on planet Earth. At the time of his death, he was recognized as a provocative and creative thinker.”
George Dyson also attested to his father’s fascination and comprehensive reach across disciplines.
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“Taking advantage of a short attention span and an aversion to bureaucracy, he contributed to five fields of mathematics and eleven fields of physics, as well as to theoretical biology, engineering, operations research, literature, and public affairs,” the younger Dyson said. “Many of his ideas were controversial, with one of his guiding principles being that ‘It is better to be wrong than to be vague.’”
The approach of the researchers behind the new study could offer a more fruitful path in the search for extraterrestrial intelligence, said Tomotsugu Goto, an associate professor of astronomy at the National Tsing Hua University in Taiwan. He also was not involved with the study.
“However, contamination by circumstellar debris disks, which mimic Dyson Sphere infrared signatures, remains a concern,” he added in an email. “Authors argue that the debris disks around (dwarf stars) are rare, but the 7 candidate authors selected out of 5 million sources are also rare. Despite this, the seven candidates warrant further investigation with powerful telescopes for a more definitive evaluation.”
‘Dyson spheres’ were theorized as a way to detect alien life. Scientists say they’ve found potential evidence
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What would be the ultimate solution to the energy problems of an advanced civilization? Renowned British American physicist Freeman Dyson theorized it would be a shell made up of mirrors or solar panels that completely surrounds a star — harnessing all the energy it produces.
“One should expect that, within a few thousand years of its entering the stage of industrial development, any intelligent species should be found occupying an artificial biosphere which completely surrounds its parent star,” wrote Dyson in a 1960 paper in which he first explained the concept
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If it sounds like science fiction, that’s because it is: Dyson took the idea from Olaf Stapledon’s 1937 novel “Star Maker,” and he was always open about that. The late scientist was a professor emeritus at the Institute of Advanced Study in Princeton, New Jersey.
Still, coming from a thinker who some in the scientific community say might have been worthy of a Nobel Prize early in his career, the concept took hold and the hypothetical megastructures became known as Dyson spheres, even though the physicist later clarified that they would actually consist of “a loose collection or swarm of objects traveling on independent orbits around the star.”
In his paper, Dyson also noted that Dyson spheres would give off waste heat detectable as infrared radiation, and suggested that looking for that byproduct would be a viable method for searching for extraterrestrial life. However, he added that infrared radiation by itself would not necessarily mean extraterrestrial intelligence, and that one of the strongest reasons for searching for such sources was that new types of natural astronomical objects might be discovered.
“Scientists (at the time) were largely receptive, not to the likelihood that alien civilisations would be found to exist, but that a search for waste heat would be a good place to look,” said George Dyson, a technology writer and author and the second of Dyson’s six children, via email. “Science fiction, from ‘Footfall’ to ‘Star Trek,’ took the idea and ran with it, while social critics adopted the Dyson sphere as a vehicle for questioning the wisdom of unlimited technological growth.”
Broken spheres
Dyson died in 2020 before any of his spheres could be found — although they are just one of a dozen ideas that bear his name.
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“As a young scientist, Dyson showed that three competing quantum theories were actually the same theory — he summarily ended the competition,” said William Press, the Leslie Surginer Professor of Computer Science and Integrative Biology at the University of Texas at Austin. He was not involved in the study. “Later, he applied his genius to areas of astronomy, cosmology, the extraterrestrial realm, and also the very real problem of nuclear proliferation here on planet Earth. At the time of his death, he was recognized as a provocative and creative thinker.”
George Dyson also attested to his father’s fascination and comprehensive reach across disciplines.
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“Taking advantage of a short attention span and an aversion to bureaucracy, he contributed to five fields of mathematics and eleven fields of physics, as well as to theoretical biology, engineering, operations research, literature, and public affairs,” the younger Dyson said. “Many of his ideas were controversial, with one of his guiding principles being that ‘It is better to be wrong than to be vague.’”
The approach of the researchers behind the new study could offer a more fruitful path in the search for extraterrestrial intelligence, said Tomotsugu Goto, an associate professor of astronomy at the National Tsing Hua University in Taiwan. He also was not involved with the study.
“However, contamination by circumstellar debris disks, which mimic Dyson Sphere infrared signatures, remains a concern,” he added in an email. “Authors argue that the debris disks around (dwarf stars) are rare, but the 7 candidate authors selected out of 5 million sources are also rare. Despite this, the seven candidates warrant further investigation with powerful telescopes for a more definitive evaluation.”
Why axolotls seem to be everywhere — except in the one lake they call home
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Scientist Dr. Randal Voss gets the occasional reminder that he’s working with a kind of superstar. When he does outreach events with his laboratory, he encounters people who are keen to meet his research subjects: aquatic salamanders called axolotls.
The amphibians’ fans tell Voss that they know the animals from the internet, or from caricatures or stuffed animals, exclaiming, “‘They’re so adorable, we love them,’” said Voss, a professor of neuroscience at the University of Kentucky College of Medicine. “People are drawn to them.”
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Take one look at an axolotl, and it’s easy to see why it’s so popular. With their wide eyes, upturned mouths and pastel pink coloring, axolotls look cheerful and vaguely Muppet-like.
They’ve skyrocketed in pop culture fame, in part thanks to the addition of axolotls to the video game Minecraft in 2021. These unusual salamanders are now found everywhere from Girl Scout patches to hot water bottles. But there’s more to axolotls than meets the eye: Their story is one of scientific discovery, exploitation of the natural world, and the work to rebuild humans’ connection with nature.
A scientific mystery
Axolotl is a word from Nahuatl, the Indigenous Mexican language spoken by the Aztecs and an estimated 1.5 million people today. The animals are named for the Aztec god Xolotl, who was said to transform into a salamander. The original Nahuatl pronunciation is “AH-show-LOAT”; in English, “ACK-suh-LAHT-uhl” is commonly used.
Axolotls are members of a class of animals called amphibians, which also includes frogs. Amphibians lay their jelly-like eggs in water, and the eggs hatch into water-dwelling larval states. (In frogs, these larvae are called tadpoles.)
Most amphibians, once they reach adulthood, are able to move to land. Since they breathe, in part, by absorbing oxygen through their moist skin, they tend to stay near water.
Axolotls, however, never complete the metamorphosis to a land-dwelling adult form and spend their whole lives in the water.
“They maintain their juvenile look throughout the course of their life,” Voss said. “They’re teenagers, at least in appearance, until they die.”
President Donald Trump wants to bring back American manufacturing in ways that would reshape the United States economy to look more like China’s. The campaign, which has led to a rapidly escalating trade war with China, has given ample social media fodder to Chinese and American observers alike.
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Announcing a series of sweeping tariffs in a move dubbed “Liberation Day,” Trump said last week that it will lead factories to move production back to American shores, boosting the U.S. economy after “foreign leaders have stolen our jobs, foreign cheaters have ransacked our factories, and foreign scavengers have torn apart our once beautiful American dream.”
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In a Truth Social post Wednesday, Trump announced that he is raising tariffs on goods imported from China to 125%, up from the 104% that took effect the same day, due to “the lack of respect that China has shown to the World’s Markets.” Higher targeted tariffs on other countries have been paused for 90 days, although the 10% baseline tariff will remain in place for all countries.
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Meme-makers and Chinese government officials have in recent days begun pointing out the irony of Trump’s tariff-driven manufacturing pivot through AI-generated satire and political cartoons that have percolated online, with many American users boosting the jokes.
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Axolotl problems
As Mexico City grew and became more industrialized, the need for water brought pumps and pipes to the lake, and eventually, “it was like a bad, smelly pond with rotten water,” Zambrano said. “All of our aquatic animals suffer with bad water quality, but amphibians suffer more because they have to breathe with the skin.”
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To add to the axolotls’ problems, invasive fish species such as carp and tilapia were introduced to the lake, where they feed on axolotl eggs. And a 1985 earthquake in Mexico City displaced thousands of people, who found new homes in the area around the lake, further contributing to the destruction of the axolotls’ habitat.
These combined threats have devastated axolotl populations. According to the International Union for Conservation of Nature, there are fewer than 100 adult axolotls left in the wild. The species is considered critically endangered.
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While the wild axolotls of Lake Xochimilco have dwindled to near-extinction, countless axolotls have been bred for scientific laboratories and the pet trade. “The axolotl essentially helped establish the field of experimental zoology,” Voss said.
In 1864, a French army officer brought live axolotls back to Europe, where scientists were surprised to learn that the seemingly juvenile aquatic salamanders were capable of reproduction. Since then, scientists around the world have studied axolotls and their DNA to learn about the salamanders’ unusual metamorphosis (or lack thereof) as well as their ability to regrow injured body parts.
In addition to their role in labs, axolotls have become popular in the exotic pet trade (though they are illegal to own in California, Maine, New Jersey and Washington, DC). However, the axolotls you might find at a pet shop are different from their wild relatives in Lake Xochimilco. Most wild axolotls are a dark grayish brown. The famous pink axolotls, as well as other color variants such as white, blue, yellow and black, are genetic anomalies that are rare in the wild but selectively bred for in the pet trade.
What’s more, “most of the animals in the pet trade have a very small genetic variance,” Zambrano said. Pet axolotls tend to be inbred and lack the wide flow of different genes that makes up a healthy population in the wild. That means that the axolotl extinction crisis can’t simply be solved by dumping pet axolotls into Lake Xochimilco. (Plus, the pet axolotls likely wouldn’t fare well with the poor habitat conditions in the lake.)