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Atlantic
19 hours ago
- Science
- Atlantic
He Won the Nobel Prize for Physics. Then He Changed His Mind.
Adam Riess was 27 years old when he began the work that earned him the Nobel Prize in Physics, and just 41 when he received it. Earlier this year, Riess, who is now in his early 50s, pulled a graph-paper notebook off a bookshelf in his office at Johns Hopkins University so that I could see the yellowing page on which he'd made his famous calculations. He told me how these pen scratches led to a new theory of the universe. And then he told me why he now thinks that theory might be wrong. For nearly a century, astronomers have known that the universe is expanding, because the galaxies that we can see around us through telescopes are all rushing away. Riess studied how they moved. He very carefully measured the distance of each one from Earth, and when all the data came together, in 1998, the results surprised him. They were 'shocking even,' he told his colleagues in a flustered email that he sent on the eve of his honeymoon. A striking relationship had emerged: The farther away that galaxies were, the faster they were receding. This 'immediately suggested a profound conclusion,' he said in his Nobel Prize lecture. Something is causing the expansion of the universe to accelerate. Riess's genius lies in making precise observations, but the task of explaining the accelerating expansion that he discovered fell to theorists. They proposed the existence of dark energy: a faint, repulsive force that pervades all of empty space. The amount of dark energy that fits inside your bedroom, say, isn't very strong. It won't blow the walls out. But when dark energy's power sums across truly cosmic volumes of space, it can drive galaxy clusters apart. And as this process puts more space between those galaxies, the repulsive force only strengthens, speeding up the expansion of the universe. Telescopes can see hundreds of billions of galaxies today, but trillions upon trillions of years from now, dark energy will have driven them all out of sight. Eventually, it will dilute every last bit of matter and energy into a cold equilibrium, a thin gruel of nothingness. By doing the work that led to the discovery of dark energy, Riess had helped add the final piece to what has since come to be called the 'standard model of cosmology.' Indeed, few people played a larger role in establishing the standard model as the field's dominant theory of how the universe began, how it organized itself into galaxies, and how it will end. But in recent years, cosmologists, the people who study the universe on the largest scales of space and time, have begun to worry that this story, and particularly its final act, might be wrong. Some talk of revolution. A growing number now say that the standard model should be replaced. Adam Riess is among them. Whenever a big theory of the universe is teetering, the old guard tends to close ranks; hence, the classic joke about science progressing one funeral at a time. Riess easily could have joined the old guard. He could have been its commanding officer. When he returned from Stockholm with his prize in 2011, he found that his academic life had changed. People around him started to behave oddly, he told me. Some clammed up. Others argued with him about trivial things, he said, perhaps so they could boast of having dunked on a Nobel laureate. Riess was besieged with invitations to sit on panels, give talks, and judge science fairs. He was asked to comment on political issues that he knew nothing about. He told me he was even recruited to run major scientific institutions. Riess wondered about that path—being the big boss of a NASA mission or gliding around a leafy university as its chancellor. He could see the appeal, but he hated fundraising, and unlike other, older Nobel laureates, he said, Riess still felt that he had scientific contributions to make, not as an administrator, but as a frontline investigator of capital- n Nature. 'Scientists sometimes tell themselves this myth: I'll go lead this thing, and then I'll come back and do research,' he told me. But then, by the time they've finished up with their administrative roles, they've lost touch with the data. They become clumsy with the latest software languages. 'The science passes them by,' Riess said. Riess decided to stick with research. There was plenty to do. The standard model had not solved cosmology. Even in 2011, people knew that the theory was lacking some important details. For one, 96 percent of the standard model's universe is made up of dark energy and dark matter—and yet no scientist had ever detected either one directly. Cosmologists had good reasons to believe that both exist in some form, but any intuitions about how one might find either in the actual universe had not proved out. Something major seemed to be missing from the picture. To get a better handle on these mysteries, theorists needed some new data. They badly wanted to know the rate at which the universe expands at different times, and for that they had to know the distances to galaxies from Earth with greater precision. This was Riess's specialty: He would wait until he saw a certain kind of star explode in a far-off galaxy, and then he'd photograph its unfolding detonation in real time. He knew these supernovas always reached a certain luminosity, which meant he could figure out how far away they were by measuring their brightness in his telescope. The dimmer they were, the farther away. I'm making this sound a lot easier than it is. Taking a snapshot of an exploding star from tens of millions of light-years away involves many subtleties. You have to subtract out light from the bright stars that surround it, in its own galaxy. The glow of the Milky Way will also sneak into your images, and so will the sun's; you have to get rid of those too. At the same time, interstellar dust clouds near the star will block some of its light, as will dust in the Milky Way. These dimming effects must be accounted for. The circuits and other parts of your telescope will add noise to your image. The hundreds of thousands of pixels in your camera aren't all the same, and their differences will need to be sussed out ahead of every observation. Riess had never stopped trying to master these delicate additions and subtractions of light. Within the field, his measurements have long been regarded as the most precise, according to Colin Hill, a cosmologist at Columbia who does not work with Riess. But in 2011, Riess and his team developed an even better technique for measuring cosmic distances with the Hubble Space Telescope. (The idea came to him in the swimming pool, he said.) As these new and better data piled up, a problem soon emerged. With each measured distance to another galaxy, Riess would update his calculation of the current expansion rate of the universe. To his alarm, the answers he was getting differed from those produced another way. Some cosmologists don't bother with the distances to galaxies and look, instead, at the afterglow of the Big Bang. They can then take the expansion rate that they see in that snapshot of the early universe and extrapolate it forward on the basis of assumptions from the standard model. In other words, the latter approach takes it as a given that the standard model is correct. Riess expected that this discrepancy between the two expansion rates would fade with further observations. But it was stubborn. The more he looked at distant galaxies, the more pronounced the difference became. Indeed, the mere fact of its existence presented the cosmologists with a serious problem. They became so vexed that they had to give it a name: the Hubble tension. Riess wondered if the observations of the early universe that fed into the other measurement's equations might be wrong. But neither he nor anyone else could find fault with them. To Riess, this suggested that the Hubble tension could be a product of a broken theory. 'It smelled like something might be wrong with the standard model,' he told me. If the standard model were to topple, the field of cosmology would be upended, and so would an important part of the grand story that we've been telling ourselves about the end of the universe. And so, naturally, with weighty matters of career, ego, and the very nature of existence at stake, the Hubble tension has led to a bit of tension among cosmologists. Some of the field's most prominent scientists told me that they still expect the problem to disappear with more data, and that Riess may be getting ahead of himself. Wendy Freedman, a professor at the University of Chicago, has made her own measurements of the local universe, using different exploding stars, and the Hubble tension shows up in her data too. But it's smaller. She told me it's too soon to tell what the problem is: her measurements, the standard model, or something else. She would want to know the distances to many more galaxies before deciding on the culprit. She would also want to see multiple methods of measurement converging. At a minimum, hers and Riess's should match up. Hill, the cosmologist from Columbia, expressed a similar view. David Spergel, the president of the Simons Foundation, who has for decades held a lot of sway in the field, agrees that it's premature to start dancing on the standard model's grave. 'Adam speaks very loudly,' Spergel said. 'He argues vociferously with whoever disagrees with him.' Riess does indeed prosecute his case with vigor. Still, no one has been able to find an error in his measurements, and not for lack of trying. His numbers have been cross-checked with observations from both the Hubble and James Webb Space Telescopes. Sean Carroll, a cosmologist and philosopher at Johns Hopkins who is not on Riess's team, told me that Riess has done a 'heroic job' of knocking systematic errors out of his measurements. But Carroll said that it is still too early to tell if the Hubble tension will hold up, and definitely too early to throw out the standard model. 'If the implications weren't so huge, people wouldn't be so skeptical,' Carroll said. Riess grew visibly exasperated when we discussed these objections. He blamed them on the 'sociology' of the field. He said that a clique of cosmologists—Spergel and 'other graybeards'—who work on the early universe have tended to dismiss conflicting data. (For the record, Riess's own goatee is observably gray.) Even so, at least one of them had come around to his view, he said. Riess had sent data to George Efstathiou, a well-respected early universe cosmologist who'd been a vocal skeptic of the Hubble tension. On his desktop computer, Riess showed me Efstathiou's reply: 'Very convincing!' I didn't want to make too much of what might have been politeness, so I followed up with Efstathiou myself. In the email that he wrote to me, he was more circumspect than he had been with Riess: 'I don't have much to say on the Hubble tension.' So far as he could tell, Riess's measurements didn't contain any errors, but he couldn't rule out the possibility that something in them was wrong. Riess believes that in time he will be vindicated. He believes that the Hubble tension will likely grow more pronounced and that more cosmologists will start to question the standard model. For someone who helped stand up that theory, he comes off as gleeful about this possibility. Maybe this is just his scientific mindset: always deferential to the data. Or perhaps he simply craves the thrill of being right, again, about the fundamental nature of the universe. When I visited Riess, back in January, he mentioned he was looking forward to a data release from the Dark Energy Spectroscopic Instrument, a new observatory on Kitt Peak, in Arizona's portion of the Sonoran Desert. DESI has 5,000 robotically controlled optic fibers. Every 20 minutes, each of them locks onto a different galaxy in the deep sky. This process is scheduled to continue for a total of five years, until millions of galaxies have been observed, enough to map cosmic expansion across time. The observatory was preparing to release its second batch of data. Riess thought the information might produce another challenge to the standard model. In the simplest version of the theory, the strength of dark energy—the faint, repulsive force that's everywhere in the universe, pushing it apart—is fixed for all eternity. But DESI's first release, last year, gave some preliminary hints that dark energy was stronger in the early universe, and that its power then began to fade ever so slightly. On March 19, the team followed up with the larger set of data that Riess was awaiting. It was based on three years of observations, and the signal that it gave was stronger: Dark energy appeared to lose its kick several billion years ago. This finding is not settled science, not even close. But if it holds up, a 'wholesale revision' of the standard model would be required, Hill told me. 'The textbooks that I use in my class would need to be rewritten.' And not only the textbooks—the idea that our universe will end in heat death has escaped the dull, technical world of academic textbooks. It has become one of our dominant secular eschatologies, and perhaps the best-known end-times story for the cosmos. And yet it could be badly wrong. If dark energy weakens all the way to zero, the universe may, at some point, stop expanding. It could come to rest in some static configuration of galaxies. Life, especially intelligent life, could go on for a much longer time than previously expected. If dark energy continues to fade, as the DESI results suggest is happening, it may indeed go all the way to zero, and then turn negative. Instead of repelling galaxies, a negative dark energy would bring them together into a hot, dense singularity, much like the one that existed during the Big Bang. This could perhaps be part of some larger eternal cycle of creation and re-creation. Or maybe not. The point is that the deep future of the universe is wide open. I called Riess after the DESI results came out, to see how he was feeling. He told me that he had an advance look at them. When he'd opened the data file in his office, a smile spread across his face. He'd been delighted to see another tough result for the standard model. He compared the theory to an egg that is breaking. 'It's not going to cleave neatly in one place,' he said. 'You would expect to see multiple cracks opening up.' Whether the cracks—if they really are cracks—will widen remains to be seen. Many new observations will come, not just from DESI, but also from the new Vera Rubin Observatory in the Atacama Desert, and other new telescopes in space. On data-release days for years to come, the standard model's champions and detractors will be feverishly refreshing their inboxes. For the moment, though, Riess believes that the theorists have become complacent. When he reaches out to them for help in making sense of his empirical results, their responses disappoint him. 'They're like, Yeah, that's a really hard problem,' he said. 'Sometimes, I feel like I am providing clues and killing time while we wait for the next Einstein to come along.' When I talked to Riess for the last time, he was at a cosmology conference in Switzerland. He sounded something close to giddy. 'When there's no big problems and everything's just kind of fitting, it's boring,' he said. Now among his colleagues, he could feel a new buzz. The daggers are out. A fight is brewing. 'The field is hot again,' he told me. A new universe suddenly seems possible.
Newsweek
a day ago
- Science
- Newsweek
Mysterious Surface Changes on Jupiter's Moon Point to Something Deep Below
Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources. Newsweek AI is in beta. Translations may contain inaccuracies—please refer to the original content. The icy surface of Jupiter's moon Europa appears to be constantly changing, new data from the James Webb Space Telescope has revealed. This phenomena, the team explained, is heightened in so-called "chaos regions" where surface features like cracks, plains and ridges end up jumbled and ensnared together. "We think that the surface is fairly porous and warm enough in some areas to allow the ice to recrystallize rapidly," said paper author and geologist Richard Cartwright of Johns Hopkins University in a statement. The different rates of crystallization across the icy moon point to a complex mix of geological processes at play—and provide further evidence for Europa harboring a liquid ocean beneath its frozen surface. An artist's impression of Europa, with Jupiter in the background An artist's impression of Europa, with Jupiter in the background dottedhippo/iStock / Getty Images Plus Astronomers refer to what we would call ice as "water ice." This distinguishes it from other frozen molecules such as carbon dioxide in the form of "dry ice," for example. Here on Earth, water ice has a hexagonal crystalline structure that results from the hydrogen bonding at play between the water molecules. (This structure actually spreads out the molecules more than in liquid water, making ice less dense than water, explaining why ice floats.) On the surface of Europa, however, water ice is constantly bombarded by charged particles, disrupting the crystalline structure to form "amorphous ice" with a disordered layout. Scientists have long speculated that Europa's surface is covered by a very thin veneer of amorphous ice—only around a fiftieth of an inch thick—which shields crystalline ice beneath. In the new study, however, the researchers found evidence of crystalline ice both at depth but also on the surface of Europa, in particular in an area known as Tara Regio. "Also, in this same region—generally referred to as a chaos region—we see a lot of other unusual things," said Cartwright. These, he explained, includes "the best evidence for sodium chloride, like table salt, probably originating from its interior ocean. We also see some of the strongest evidence for carbon dioxide and hydrogen peroxide on Europa. The chemistry in this location is really strange and exciting." Map of water ice types on Europa Map of water ice types on Europa SwRI According to the researchers, this region of fractured surface materials hints at geological processes pushing up materials from below. "Our data showed strong indications that what we are seeing must be sourced from the interior, perhaps from a subsurface ocean nearly 20 miles beneath Europa's thick icy shell," said paper author and physicist Ujjwal Raut of the Southwest Research Institute in a statement. "When we see evidence of carbon dioxide at the surface, we think it must have come from an ocean below the surface. "The evidence for a liquid ocean underneath Europa's icy shell is mounting, which makes this so exciting as we continue to learn more." Do you have a tip on a science story that Newsweek should be covering? Do you have a question about Europa? Let us know via science@ Reference Cartwright, R. J., Hibbitts, C. A., Holler, B. J., Raut, U., Nordheim, T. A., Neveu, M., Protopapa, S., Glein, C. R., Leonard, E. J., Roth, L., Beddingfield, C. B., & Villanueva, G. L. (2025). JWST Reveals Spectral Tracers of Recent Surface Modification on Europa. The Planetary Science Journal, 6(5), 125.
Yahoo
a day ago
- Business
- Yahoo
Lantern Pharma Inc. (LTRN)'s LP-184 Shows 345% Survival Gain in Rare Pediatric Brain Tumor Models
Lantern Pharma Inc. (NASDAQ:LTRN)'s investigational drug LP-184 has achieved a major milestone in the fight against pediatric brain cancer, following independent validation by Johns Hopkins University researchers. New preclinical data presented at the Society for Neuro-Oncology's Pediatric Conference showed LP-184 extended survival dramatically in mouse models of atypical teratoid rhabdoid tumors (ATRT), a rare and aggressive childhood brain cancer. In one model, median survival soared from 20 to 89 days, which is a 345% improvement, while another saw an increase from 68 to 98 days. The studies also confirmed strong anti-tumor activity across multiple ATRT subtypes and favorable blood-brain barrier penetration, with no apparent toxicity observed in treated animals. A healthcare provider holding an MRI scan of a patient with a traumatic brain injury. These results strengthen the scientific foundation for Lantern Pharma Inc. (NASDAQ:LTRN)'s FDA Rare Pediatric Disease Designation for LP-184 in ATRT and pave the way for a planned pediatric clinical trial, expected to launch in late 2025 or early 2026. LP-184, a next-generation acylfulvene drug, targets tumors with epigenetic dysregulation, such as those with SMARCB1 gene loss, a hallmark of ATRT. With current treatments offering poor outcomes and high toxicity, Lantern Pharma Inc. (NASDAQ:LTRN)'s LP-184's single-agent efficacy could mark a breakthrough for children facing this devastating diagnosis. LTRN closed over 9% higher on May 29. While we acknowledge the potential of LTRN to grow, our conviction lies in the belief that some AI stocks hold greater promise for delivering higher returns and have limited downside risk. If you are looking for an AI stock that is more promising than LTRN and that has 100x upside potential, check out our report about this READ NEXT: and Disclosure: None. Error in retrieving data Sign in to access your portfolio Error in retrieving data Error in retrieving data Error in retrieving data Error in retrieving data
New Indian Express
a day ago
- Politics
- New Indian Express
Chinese students 'anxious' and 'angry' after Rubio vows to revoke US visas
HONG KONG: Chinese students studying in the US are scrambling to figure out their futures after US Secretary of State Marco Rubio announced on Wednesday that some of them would have their visas revoked. The US will begin revoking the visas of some Chinese students, including those studying in 'critical fields" and "those with connections to the Chinese Communist Party," according to the announcement. China is the second-largest country of origin for international students in the United States, behind only India. In the 2023-2024 school year, more than 270,000 international students were from China, making up roughly a quarter of all foreign students in the US. Rubio's announcement was a 'new version of the Chinese Exclusion Act,' said Liqin, a Chinese student at Johns Hopkins University, who asked to be identified only by his first name out of fear of retaliation. He was referring to a 19th-century law that prohibited Chinese from immigrating to the US and banned Chinese people already in the US from getting citizenship. He said Wednesday was the first time he thought about leaving the US after spending a third of his life here. Chinese international students are a point of tension China's Foreign Ministry spokesperson, Mao Ning, called the US decision unreasonable. 'Such a politicized and discriminatory action lays bare the US lie that it upholds so-called freedom and openness," she said Thursday, adding that China has lodged a protest with the US. The issue of Chinese students studying overseas has long been a point of tension in the bilateral relationship. In 2019, during Trump's first term, China's Ministry of Education warned students about visa issues in the US, with rising rejection rates and shortening of visas. Last year, the Chinese Foreign Ministry protested that a number of Chinese students were unfairly interrogated and sent home upon arrival at US airports. Chinese state media has long hyped gun violence in the US and violent protests during the pandemic, and portrayed the US as a dangerous place that wasn't safe for its citizens. The tense bilateral relationship has also meant that some Chinese students are opting to study in the UK or other countries over the US after the pandemic. Zou Renge, a 27-year-old public policy master's student at the University of Chicago, said she had planned to take some time off and work in humanitarian aid programs abroad after graduating at the end of this year. But now, she will refrain from leaving the US and will look for jobs in the meantime. 'In a very uncertain environment, I'll try my best to find myself a solution,' she said.
Global News
a day ago
- Politics
- Global News
U.S. to revoke Chinese student visas, leaving some worried about futures
Chinese students studying in the U.S. are scrambling to figure out their futures after Secretary of State Marco Rubio announced Wednesday that some of them would have their visas revoked. The U.S. will begin revoking the visas of some Chinese students, including those studying in 'critical fields' and 'those with connections to the Chinese Communist Party,' according to the announcement. China is the second-largest country of origin for international students in the United States, behind only India. In the 2023-2024 school year, more than 270,000 international students were from China, making up roughly a quarter of all foreign students in the U.S. Rubio's announcement was a 'new version of the Chinese Exclusion Act,' said Liqin, a Chinese student at Johns Hopkins University, who asked to be identified only by his first name out of fear of retaliation. He was referring to a 19th-century law that prohibited Chinese from immigrating to the U.S. and banned Chinese people already in the U.S. from getting citizenship. He said Wednesday was the first time he thought about leaving the U.S. after spending a third of his life here. Story continues below advertisement Chinese international students are a point of tension China's Foreign Ministry spokesperson, Mao Ning, called the U.S. decision unreasonable. 'Such a politicized and discriminatory action lays bare the U.S. lie that it upholds so-called freedom and openness,' she said Thursday, adding that China has lodged a protest with the U.S. The issue of Chinese students studying overseas has long been a point of tension in the bilateral relationship. In 2019, during Trump's first term, China's Ministry of Education warned students about visa issues in the U.S., with rising rejection rates and shortening of visas. Last year, the Chinese Foreign Ministry protested that a number of Chinese students were unfairly interrogated and sent home upon arrival at U.S. airports. 1:57 Harvard challenges foreign student ban amid escalating clash with Trump Chinese state media has long hyped gun violence in the U.S. and violent protests during the pandemic, and portrayed the U.S. as a dangerous place that wasn't safe for its citizens. The tense bilateral relationship has also meant that some Chinese students are opting to study in the U.K. or other countries over the U.S. after the pandemic. Story continues below advertisement Zou Renge, a 27-year-old public policy master's student at the University of Chicago, said she had planned to take some time off and work in humanitarian aid programs abroad after graduating at the end of this year. Get daily National news Get the day's top news, political, economic, and current affairs headlines, delivered to your inbox once a day. Sign up for daily National newsletter Sign Up By providing your email address, you have read and agree to Global News' Terms and Conditions and Privacy Policy But now, she will refrain from leaving the U.S. and will look for jobs in the meantime. 'In a very uncertain environment, I'll try my best to find myself a solution,' she said. Hong Kong seeks to draw in talent amid uncertainty Some were eager to capitalize on the uncertainty facing international students in the U.S. Hong Kong's leader John Lee told lawmakers on Thursday that the city would welcome any students who have been discriminated against by American policies to study in the city. 'The students who face unfair treatment can come from different countries beyond the U.S. I think this is an opportunity for Hong Kong,' he said. 'We will work with our universities to provide the best support and assistance.' Story continues below advertisement That followed a widely shared post by the Hong Kong University of Science and Technology (HKUST) inviting Harvard students to 'continue their academic pursuits' there after Trump said he would revoke the university's ability to accept international students. Other Hong Kong universities including the Chinese University of Hong Kong and City University of Hong Kong also said they would streamline or facilitate applications from international students coming from top universities in the U.S. 3:18 Harvard sues Trump administration for blocking enrolment of foreign students Hong Kong, a former British colony that returned to China in 1997, is a popular destination for mainland Chinese students to pursue their university degrees because of its international image and relative freedoms. The city launched a new visa scheme in 2022 to counter the exodus of expatriates and local professionals that occurred after Beijing imposed a national security law to quell dissent and during the COVID-19 pandemic. Story continues below advertisement Will Kwong, managing director at Hong Kong's AAS Education Consultancy, said his company was helping students with offers from American universities to apply to other institutions, predominantly in Britain and Australia, so that they had alternative choices. U.S. was known for diversity and this will hurt it, students say 'Having fewer international exchanges is definitely not good for America's development,' said Zhang Qi, a postdoctoral fellow in Beijing. 'This could be a positive change for China's development. More talented individuals may choose to stay at Tsinghua or Peking University, or with the Chinese Academy of Sciences and other top institutions in China, which would benefit the development of domestic science and technology.' For many, there is little they can do as they now wait for the fallout from the move. Chen, a Chinese student at Purdue University who only gave his last name out of concern for retaliation by the Trump administration, has been waiting anxiously in China for his visa approval. But he was also angry, and said this was the exact opposite of what he thought the U.S. stood for. Story continues below advertisement 'I was expecting freedom and tolerance. The U.S. was known for its diversity which allows international students to fit in, but it is a pity to see such change,' he said. —Fu Ting reported from Washington, Wu from Bangkok. Associated Press researcher Shihuan Chen and video producer Olivia Zhang in Beijing contributed to this report.
