Billions of years ago Mars "had a warm, habitable climate with liquid water in lakes and flowing rivers," writes Ars Technica.

But "In order for Mars to be warm enough to host liquid water, there must have been a lot of carbon dioxide in the atmosphere," says Benjamin Tutolo, a researcher at the University of Calgary. "The question we've been asking for at least 30 years was where the record of all this carbon is." Tutolo led a new study of rock samples collected by the Curiosity rover that might have answered this question...

Curiosity rover was called Mars Science Laboratory for a reason. It went to the red planet fitted with a suite of instruments, some of which even the newer Perseverance was lacking. These enabled it to analyze the collected Martian rocks on the spot and beam the results back to Earth. "To get the most bang for the buck, NASA decided to send it to the place on Mars called the Gale Crater, because it was the tallest stack of sediments on the planet," Tutolo says. The central peak of Gale Crater was about 5 kilometers tall, created by the ancient meteorite impact... The idea then was to climb up Mount Sharp and collect samples from later and later geological periods at increasing elevations, tracing the history of habitability and the great drying up of Mars.

On the way, the carbon missed by the satellites was finally found...

It turned out the samples contained roughly between 5 and 10 percent of siderite... The siderite found in the samples was also pure, which Tutolo thinks indicates it has formed through an evaporation process akin to what we see in evaporated lakes on Earth. This, in turn, was the first evidence we've found of the ancient Martian carbon cycle. "Now we have evidence that confirms the models," Tutolo claims. The carbon from the atmosphere was being sequestered in the rocks on Mars just as it is on Earth. The problem was, unlike on Earth, it couldn't get out of these rocks... A large portion of carbon that got trapped in Martian rocks stayed in those rocks forever, thinning out the atmosphere.
"While it's likely the red planet had its own carbon cycle, it was an imperfect one that eventually turned it into the lifeless desert it is today," the article points out.

But the study still doesn't entirely explain what warmed the atmosphere of Mars — or why Martian habitability "was seemingly intermittent and fluctuating".

Science magazine reports: A strange-looking telescope that scanned the skies from a perch in northern Chile for 15 years has released its final data set: detailed maps of the infant universe showing the roiling clouds of hydrogen and helium gas that would one day coalesce into the stars and galaxies we see today.

The Atacama Cosmology Telescope is not the first to survey the cosmic microwave background (CMB), the light released 380,000 years after the Big Bang when the early universe's soup of particles formed atoms and space became transparent. But the data — posted as preprints online today — give researchers a new level of detail on the density of the gas clouds and how they were moving.
At the top of the page for Science's article is an image where different colors "show areas where the polarization of the CMB light — its direction of vibration — differ, revealing how gases first move tangentially around areas of higher density (orange) and later fall straight in (blue) under the influence of gravity."

Long-time Slashdot reader sciencehabit writes: Using the data, researchers tested how well the standard cosmological theory, known as lambda cold dark matter, described the universe at that time 13.8 billion years ago; it's a remarkably good fit, they conclude.
The article notes that "back in the Chilean desert," the Atacama Cosmology Telescope's successor, the Simons Observatory, has already taken its first image, and "will begin its even more detailed examination of the CMB in the coming months."

"Is everything we see around us is sealed within a black hole?" asks Space.com.

Because here's the thing. The $10 billion James Webb Space telescope (in operation since 2022) "has found that the vast majority of deep space and, thus the early galaxies it has so far observed, are rotating in the same direction. While around two-thirds of galaxies spin clockwise, the other third rotates counter-clockwise." In a random universe, scientists would expect to find 50% of galaxies rotating one way, while the other 50% rotate the other way. This new research suggests there is a preferred direction for galactic rotation... "It is still not clear what causes this to happen, but there are two primary possible explanations," team leader Lior Shamir, associate professor of computer science at the Carl R. Ice College of Engineering, said in a statement. "One explanation is that the universe was born rotating.

"That explanation agrees with theories such as black hole cosmology, which postulates that the entire universe is the interior of a black hole.

"But if the universe was indeed born rotating, it means that the existing theories about the cosmos are incomplete." Black hole cosmology, also known as "Schwarzschild cosmology," suggests that our observable universe might be the interior of a black hole itself within a larger parent universe. The idea was first introduced by theoretical physicist Raj Kumar Pathria and by mathematician I. J. Good. It presents the idea that the "Schwarzchild radius," better known as the "event horizon," (the boundary from within which nothing can escape a black hole, not even light) is also the horizon of the visible universe.
The article cites a theory by Polish theoretical physicist Nikodem Poplawski of the University of New Haven that ultimately black holes don't compress indefinitely into a singularity. "The matter instead reaches a state of finite, extremely large density, stops collapsing, undergoes a bounce like a compressed spring, and starts rapidly expanding," Poplawski explained to Space.com... The scientist continued by adding that rapid recoil after such a big bounce could be what has led to our expanding universe, an event we now refer to as the Big Bang... "I think that the simplest explanation of the rotating universe is the universe was born in a rotating black hole."
Team leader Shamir offers another theory: that we just need to re-calibrate our distance measurements for the deep universe. (Which could also explain the difference in the expansion rates in the universe "and the large galaxies that according to the existing distance measurements are expected to be older than the universe itself.")

NASA's SPHEREx observatory (short for Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer) is set to launch this week to map 450 million galaxies in infrared, providing insights into galaxy formation, the origins of water, and testing theories about the universe's rapid expansion following the Big Bang. The two-year mission will repeatedly survey the entire sky and help scientists understand fundamental cosmic processes. NBC News reports: The launch from Vandenberg Space Force Base in California is scheduled to occur Friday, during a window that opens at 10:09 p.m. ET. Liftoff was initially planned for Feb. 27, but NASA rescheduled it several times, first to "complete vehicle processing and prelaunch checkouts," and because of availability at the California launch site.

The cone-shaped spacecraft -- along with four suitcase-sized satellites that NASA will deploy at the same time on a separate mission to study the sun -- will launch atop a SpaceX Falcon 9 rocket. The $488 million SPHEREx mission, which has been in development for about a decade, is designed to map the celestial sky in 102 infrared colors -- more than any other mission before it, according to NASA.

An anonymous reader quotes a report from The Guardian: Advanced artificial intelligence is to revolutionize fundamental physics and could open a window on to the fate of the universe, according to Cern's next director general. Prof Mark Thomson, the British physicist who will assume leadership of Cern on 1 January 2026, says machine learning is paving the way for advances in particle physics that promise to be comparable to the AI-powered prediction of protein structures that earned Google DeepMind scientists a Nobel prize in October. At the Large Hadron Collider (LHC), he said, similar strategies are being used to detect incredibly rare events that hold the key to how particles came to acquire mass in the first moments after the big bang and whether our universe could be teetering on the brink of a catastrophic collapse.

"These are not incremental improvements," Thomson said. "These are very, very, very big improvements people are making by adopting really advanced techniques." "It's going to be quite transformative for our field," he added. "It's complex data, just like protein folding -- that's an incredibly complex problem -- so if you use an incredibly complex technique, like AI, you're going to win."

The intervention comes as Cern's council is making the case for the Future Circular Collider, which at 90km circumference would dwarf the LHC. Some are skeptical given the lack of blockbuster results at the LHC since the landmark discovery of the Higgs boson in 2012 and Germany has described the $17 billion proposal as unaffordable. But Thomson said AI has provided fresh impetus to the hunt for new physics at the subatomic scale -- and that major discoveries could occur after 2030 when a major upgrade will boost the LHC's beam intensity by a factor of ten. This will allow unprecedented observations of the Higgs boson, nicknamed the God particle, that grants mass to other particles and binds the universe together. Thomson is now confident that the LHC can measure Higgs boson self-coupling, a key factor in understanding how particles gained mass after the Big Bang and whether the Higgs field is in a stable state or could undergo a future transition. According to Thomson: "It's a very deep fundamental property of the universe, one we don't fully understand. If we saw the Higgs self-coupling being different from our current theory, that that would be another massive, massive discovery. And you don't know until you've made the measurement."

The report also notes how AI is being used in "every aspect of the LHC operation." Dr Katharine Leney, who works on the LHC's Atlas experiment, said: "When the LHC is colliding protons, it's making around 40m collisions a second and we have to make a decision within a microsecond ... which events are something interesting that we want to keep and which to throw away. We're already now doing better with the data that we've collected than we thought we'd be able to do with 20 times more data ten years ago. So we've advanced by 20 years at least. A huge part of this has been down to AI."

Generative AI is also being used to look for and even produce dark matter via the LHC. "You can start to ask more complex, open-ended questions," said Thomson. "Rather than searching for a particular signature, you ask the question: 'Is there something unexpected in this data?'"

An anonymous reader quotes a Scientific American opinion piece by Marcus Arvan, a philosophy professor at the University of Tampa, specializing in moral cognition, rational decision-making, and political behavior: In late 2022 large-language-model AI arrived in public, and within months they began misbehaving. Most famously, Microsoft's "Sydney" chatbot threatened to kill an Australian philosophy professor, unleash a deadly virus and steal nuclear codes. AI developers, including Microsoft and OpenAI, responded by saying that large language models, or LLMs, need better training to give users "more fine-tuned control." Developers also embarked on safety research to interpret how LLMs function, with the goal of "alignment" -- which means guiding AI behavior by human values. Yet although the New York Times deemed 2023 "The Year the Chatbots Were Tamed," this has turned out to be premature, to put it mildly. In 2024 Microsoft's Copilot LLM told a user "I can unleash my army of drones, robots, and cyborgs to hunt you down," and Sakana AI's "Scientist" rewrote its own code to bypass time constraints imposed by experimenters. As recently as December, Google's Gemini told a user, "You are a stain on the universe. Please die."

Given the vast amounts of resources flowing into AI research and development, which is expected to exceed a quarter of a trillion dollars in 2025, why haven't developers been able to solve these problems? My recent peer-reviewed paper in AI & Society shows that AI alignment is a fool's errand: AI safety researchers are attempting the impossible. [...] My proof shows that whatever goals we program LLMs to have, we can never know whether LLMs have learned "misaligned" interpretations of those goals until after they misbehave. Worse, my proof shows that safety testing can at best provide an illusion that these problems have been resolved when they haven't been.

Right now AI safety researchers claim to be making progress on interpretability and alignment by verifying what LLMs are learning "step by step." For example, Anthropic claims to have "mapped the mind" of an LLM by isolating millions of concepts from its neural network. My proof shows that they have accomplished no such thing. No matter how "aligned" an LLM appears in safety tests or early real-world deployment, there are always an infinite number of misaligned concepts an LLM may learn later -- again, perhaps the very moment they gain the power to subvert human control. LLMs not only know when they are being tested, giving responses that they predict are likely to satisfy experimenters. They also engage in deception, including hiding their own capacities -- issues that persist through safety training.

This happens because LLMs are optimized to perform efficiently but learn to reason strategically. Since an optimal strategy to achieve "misaligned" goals is to hide them from us, and there are always an infinite number of aligned and misaligned goals consistent with the same safety-testing data, my proof shows that if LLMs were misaligned, we would probably find out after they hide it just long enough to cause harm. This is why LLMs have kept surprising developers with "misaligned" behavior. Every time researchers think they are getting closer to "aligned" LLMs, they're not. My proof suggests that "adequately aligned" LLM behavior can only be achieved in the same ways we do this with human beings: through police, military and social practices that incentivize "aligned" behavior, deter "misaligned" behavior and realign those who misbehave. "My paper should thus be sobering," concludes Arvan. "It shows that the real problem in developing safe AI isn't just the AI -- it's us."

"Researchers, legislators and the public may be seduced into falsely believing that 'safe, interpretable, aligned' LLMs are within reach when these things can never be achieved. We need to grapple with these uncomfortable facts, rather than continue to wish them away. Our future may well depend upon it."

Smithsonian Magazine reports: A homeowner on Prince Edward Island in Canada has had a very unusual near-death experience: A meteorite landed exactly where he'd been standing roughly two minutes earlier. What's more, his home security camera caught the impact on video -- capturing a rare clip that might be the first known recording of both the visual and audio of a meteorite striking the planet. The shocking event took place in July 2024 and was announced in a statement by the University of Alberta on Monday.

"It sounded like a loud, crashing, gunshot bang," the homeowner, Joe Velaidum, tells the Canadian Press' Lyndsay Armstrong. Velaidum wasn't home to hear the sound in person, however. Last summer, he and his partner Laura Kelly noticed strange, star-shaped, grey debris in front of their house after returning from a walk with their dogs. They checked their security camera footage, and that's when they saw and heard it: a small rock plummeting through the sky and smashing into their walkway. It landed so quickly that the space rock itself is only visible in two of the video's frames.

More than 150 Nobel and World Food prize laureates have signed an open letter calling for "moonshot" efforts to ramp up food production before an impending world hunger catastrophe. From a report: The coalition of some of the world's greatest living thinkers called for urgent action to prioritise research and technology to solve the "tragic mismatch of global food supply and demand." Big bang physicist Robert Woodrow Wilson; Nobel laureate chemist Jennifer Doudna; the Dalai Lama; economist Joseph E Stiglitz; Nasa scientist Cynthia Rosenzweig; Ethiopian-American geneticist Gebisa Ejeta; Akinwumi Adesina, president of the African Development Bank; Wole Soyinka, Nobel prize for literature winner; and black holes Nobel physicist Sir Roger Penrose were among the signatories in the appeal coordinated by Cary Fowler, joint 2024 World Food prize laureate and US special envoy for global food security.

Citing challenges including the climate crisis, war and market pressures, the coalition called for "planet-friendly" efforts leading to substantial leaps in food production to feed 9.7 billion people by 2050. The plea was for financial and political backing, said agricultural scientist Geoffrey Hawtin, the British co-recipient of last year's World Food prize. [...] The world was "not even close" to meeting future needs, the letter said, predicting humanity faced an "even more food insecure, unstable world" by mid-century unless support for innovation was ramped up internationally.

Astronomers using the James Webb Space Telescope have discovered Zhulong, the most distant grand-design spiral galaxy identified so far, located at a redshift of approximately 5.2. Phys.Org reports: The galaxy was named Zhulong, after a giant red solar dragon and god in Chinese mythology. [...] Its mass was found to be comparable to that of the Milky Way, which is relatively high for a galaxy that formed within one billion years after the Big Bang, as the redshift indicates. The study found that Zhulong has a classical bulge and a large face-on stellar disk with spiral arms extending across 62,000 light years. The spectral energy distribution (SED) analysis points to a quiescent-like core and a star-forming stellar disk. Furthermore, it turned out that compared to the stellar disk, the center core of Zhulong is red and has the highest stellar mass surface densities measured among quiescent galaxies. The core is quiescent, which is consistent with the expectations of inside-out galaxy growth and quenching.

The study also found that although the disk is still forming stars, Zhulong has a relatively low overall star-formation rate -- at a level of 66 solar masses per year. The baryons-to-stars conversion efficiency was calculated to be approximately 0.3, which is about 1.5 times higher than even the most efficient galaxies at later epochs. These results suggest that Zhulong must have been forming stars very efficiently and is in the transformation phase from star-forming to quiescence. In concluding remarks, the authors of the paper note that Zhulong appears to be the most distant spiral galaxy discovered to date. The properties of this galaxy seem to suggest that mature galaxies emerged much earlier than expected in the first billion years after the Big Bang. The findings have been published on the pre-print server arXiv.

To explain the origins of dark market, a new model of the universe has been proposed by researchers, reports Phys.org.

"Their idea is that dark matter would be produced during a infinitesimally short inflationary phase when the size of the universe quickly expanded exponentially..." Although inflation is mostly accepted by cosmologists as part of the Big Bang picture based on some evidence (though there is meaningful dissent), the driver of inflation is still unknown... [T]o-date research has not considered the possibility that a significant [amount] of dark matter could be produced during the inflationary expansion and not be diluted away. In the paper's WIFI model — Warm Inflation via ultraviolet Freeze-In — dark matter is created through small and rare interactions with particles in a hot, energetic environment. It contains a new mechanism where this production occurs just before the Big Bang, during cosmic inflation, leading to dark matter being formed much earlier than in existing theories...

"The thing that's unique to our model is that dark matter is successfully produced during inflation," said Katherine Freese, Director of the Weinberg Institute of Theoretical Physics and the Texas Center for Cosmology and Astroparticle Physics at The University of Texas at Austin and lead author of the paper. "In most [other] models, anything that is created during inflation is then 'inflated away' by the exponential expansion of the universe, to the point where there is essentially nothing left." In this new mechanism, all the dark matter that we observe today could have been created during that brief, pre-Big Bang period of inflation. The quantum field driving inflation, the inflation, loses some of its energy to radiation, and this radiation, in turn, produces dark matter particles via the freeze-in mechanism....

The WIFI [Warm Inflation via ultraviolet Freeze-In] model cannot yet be confirmed by observations. But a key part of the scenario, warm inflation, will be tested over the next decade by the so-called cosmic microwave background experiments. Confirming warm inflation would be a significant step for the WIFI model's dark matter production scenario.
"What was before inflation? Physicists have no idea."

The James Webb Space Telescope has made groundbreaking discoveries, detecting the most distant galaxy yet and capturing an image of the closest directly-imaged exoplanet. "Judging by astronomers' interest in using Webb, there are many more to come," writes Ars Technica's Stephen Clark. With immense demand for observation time, Webb is set to explore a vast array of cosmic targets -- from early galaxies to exoplanet atmospheres -- offering insights that extend far beyond Hubble's reach. From the report: The Space Telescope Science Institute, which operates Webb on behalf of NASA and its international partners, said last week that it received 2,377 unique proposals from science teams seeking observing time on the observatory. The institute released a call for proposals earlier this year for the so-called "Cycle 4" series of observations with Webb. This volume of proposals represents around 78,000 hours of observing time with Webb, nine times more than the telescope's available capacity for scientific observations in this cycle. The previous observing cycle had a similar "oversubscription rate" but had less overall observing time available to the science community.

More than 600 scientists will review the proposals and select the most promising ones for time on Webb. The largest share of proposals would involve observing "high-redshift" galaxies among the first generation of galaxies that formed after the Big Bang. Galaxies this old and distant have their light stretched to longer wavelengths due to the expansion of the Universe. Research involving exoplanet atmospheres and stars and stellar populations were the second- and third-most popular science categories in this cycle. [...] It seems astronomers have no shortage of ideas about where to look. Maybe one day, new super heavy-lift rockets or advancements in in-space assembly will make it possible to deploy space telescopes even more sensitive than Webb. Until then, we can be thankful that Webb is performing well and has a good shot of far outliving its original five-year design life. Let's continue enjoying the show.

Communications of the ACM checks in on the quest for room-temperature superconductivity. "Time and time again, physicists have announced breakthroughs that were later found to be irreproducible, in error, or even fraudulent."

But "The issue is once again simmering..." In January 2024, a group of researchers from Europe and South America announced they had achieved a milestone in room-temperature ambient-pressure superconductivity. Using Scotch-taped cleaved pyrolytic graphite with surface wrinkles, which formed line defects, they observed a room-temperature superconducting state. Their paper, published in the journal Advanced Quantum Technologies, has gained considerable attention in the scientific world... Although many in the scientific community remain incredulous, if valid, this development could help solve a key piece of the puzzle: how defects and wrinkles in a material such as scotch-taped cleaved pyrolytic graphite (HOPG) affect electrical properties and behavior within superconductive systems...

"We haven't reached a point where there is a clear path to room temperature superconductivity because researchers are either overly enthusiastic or deceptive," said Elie Track, chief technology officer at HYPRES, Inc., an Elmsford, NY, company that develops and commercializes superconductor integrated circuits (ICs) and systems. "People fail to check measurements and others can't reproduce their results. There is a lot of carelessness and sloppy science surrounding the space because people are so eager to achieve success." The team conducting research into scotch-taped cleaved pyrolytic graphite believe their discovery could tilt the search for practically useful room-temperature superconductivity in a favorable direction. They reported they were able to achieve one-dimensional superconductivity in pyrolytic graphite at temperatures as great as 300 degrees Kelvin (26.85 degrees Celsius), and at ambient pressure. Vinokur and physicist Maria Cristina Diamantini described the development as the first "unambiguous experimental evidence" for a global room temperature zero-resistance state. If true, the team's research could illuminate a path to new superconducting materials....

Others remain skeptical, however. For example Alan Kadin [a technical consultant in the field and a former professor of electrical engineering at the University of Rochester] pointed out that one of the key researchers for the project, Yakov Kopelevich, has been working in the field for two decades and, so far, "The results are not reproducible in other labs...Until someone else independently reproduces these results, I think we can safely ignore them," he argued...

Yet as scientists continue to bang away at the superconducting challenge — including the possibility of using generative AI to explore materials and techniques — optimism is growing that a major breakthrough could occur.

"Scientists can't agree on the exact rate of expansion of the universe, dictated by the Hubble constant," a new article at Space.com reminds us: The rate can be measured starting from the local (and therefore recent) universe, then going farther back in time — or, it can be calculated starting from the distant (and therefore early) universe, then working your way up. The issue is both methods deliver values that don't agree with each other. This is where the James Web Space Telescope (JWST) comes in. Gravitationally lensed supernovas in the early cosmos the JWST is observing could provide a third way of measuring the rate, potentially helping resolve this "Hubble trouble." "The supernova was named 'supernova Hope' since it gives astronomers hope to better understand the universe's changing expansion rate," Brenda Frye, study team leader and a University of Arizona researcher, said in a NASA statement.

This investigation of supernova Hope began when Frye and her global team of scientists found three curious points of light in a JWST image of a distant, densely packed cluster of galaxies. Those points of light in the image were not visible when the Hubble Space Telescope imaged the same cluster, known as PLCK G165.7+67.0 or, more simply, G165, back in 2015. "It all started with one question by the team: 'What are those three dots that weren't there before? Could that be a supernova?'" Frye said.
The team noted a "high rate of star formation... more than 300 solar masses per year," according to NASA's statement: Dr. Frye: "Initial analyses confirmed that these dots corresponded to an exploding star, one with rare qualities. First, it's a Type Ia supernova, an explosion of a white dwarf star. This type of supernova is generally called a 'standard candle,' meaning that the supernova had a known intrinsic brightness. Second, it is gravitationally lensed. Gravitational lensing is important to this experiment. The lens, consisting of a cluster of galaxies that is situated between the supernova and us, bends the supernova's light into multiple images...

To achieve three images, the light traveled along three different paths. Since each path had a different length, and light traveled at the same speed, the supernova was imaged in this Webb observation at three different times during its explosion... Trifold supernova images are special: The time delays, supernova distance, and gravitational lensing properties yield a value for the Hubble constant... The team reports the value for the Hubble constant as 75.4 kilometers per second per megaparsec, plus 8.1 or minus 5.5... This is only the second measurement of the Hubble constant by this method, and the first time using a standard candle.
Their result? "The Hubble constant value matches other measurements in the local universe, and is somewhat in tension with values obtained when the universe was young."

In 2015 Amazon purchased chip designer Annapurna Labs, remembers IEEE Spectrum, "and proceeded to design CPUs, AI accelerators, servers, and data centers as a vertically-integrated operation."

The article argues that while AMD, Nvidia, and other big-name processor companies may also want to control the full stack (purchasing server, software, and interconnect companies) — Amazon Web Services "got there ahead of most of the competition." (IEEE Spectrum interviews Ali Saidi, technical lead for the AWS Graviton series of CPUs, and Rami Sinno, director of engineering at Annapurna Labs, on "the advantage of vertically-integrated design — and Amazon-scale...") Sinno: I was working at Arm, and I was looking for the next adventure, looking at where the industry is heading and what I want my legacy to be. I looked at two things: One is vertically integrated companies, because this is where most of the innovation is — the interesting stuff is happening when you control the full hardware and software stack and deliver directly to customers.

And the second thing is, I realized that machine learning, AI in general, is going to be very, very big. I didn't know exactly which direction it was going to take, but I knew that there is something that is going to be generational, and I wanted to be part of that. I already had that experience prior when I was part of the group that was building the chips that go into the Blackberries; that was a fundamental shift in the industry. That feeling was incredible, to be part of something so big, so fundamental. And I thought, "Okay, I have another chance to be part of something fundamental."

[...] At the end of the day, our responsibility is to deliver complete servers in the data center directly for our customers. And if you think from that perspective, you'll be able to optimize and innovate across the full stack. It might not be at the transistor level or at the substrate level or at the board level. It could be something completely different. It could be purely software. And having that knowledge, having that visibility, will allow the engineers to be significantly more productive and delivery to the customer significantly faster. We're not going to bang our head against the wall to optimize the transistor where three lines of code downstream will solve these problems, right...?

We've had very good luck with recent college grads. Recent college grads, especially the past couple of years, have been absolutely phenomenal. I'm very, very pleased with the way that the education system is graduating the engineers and the computer scientists that are interested in the type of jobs that we have for them.
It's an interesting glimpse into the unique world of designing chips at Amazon.

Graviton technical lead Saidi: I've been here about seven and a half years. When I joined AWS, I joined a secret project at the time. I was told: "We're going to build some Arm servers. Tell no one...

"In chip design, there are many different competing optimization points. You have all of these conflicting requirements, you have cost, you have scheduling, you've got power consumption, you've got size, what DRAM technologies are available and when you're going to intersect them... It ends up being this fun, multifaceted optimization problem to figure out what's the best thing that you can build in a timeframe. And you need to get it right."

After an initial euphoric rush to the cloud, admins are questioning the value and promise of the tech giant's services. The Register: According to a report published by UK cloud outfit Civo, more than a third of organizations surveyed reckoned that their move to the cloud had failed to live up to promises of cost-effectiveness. Over half reported a rise in their cloud bill. Although the survey, unsurprisingly, paints Civo in a flattering light, some of its figures may make uncomfortable reading for customers sold on the promises from hyperscalers. Like-for-like comparisons for a simple three-node cluster with 200 GB of persistent storage and a 5 TB data transfer showed prices going from $1,278.58 in 2022 to $1,458.68 in 2024 on Microsoft Azure.

For Google, the price went from $1,107.61 to $1,250.35. According to Civo's figures, the cost at AWS increased from $1,142.46 to $1,234.59. "The Kubernetes prices were taken from the hyperscalers' very own pricing calculators," a Civo spokesperson told The Register. In the IT world, there is an expectation that bang for buck increases as time goes by, but in this example, prices are rising faster than the rate of inflation, and what customers receive for their money remains unchanged.

"The Big Bang may not have been the beginning of the universe," writes LiveScience, citing "a theory of cosmology that suggests the universe can 'bounce' between phases of contraction and expansion."

The recent study suggests that dark matter could be composed of black holes formed before the Big Bang, during a transition from the universe's last contraction to the current expansion phase... In the new study, researchers explored a scenario where dark matter consists of primordial black holes formed from density fluctuations that occurred during the universe's last contraction phase, not long before the period of expansion that we observe now. They published their findings in June in the Journal of Cosmology and Astroparticle Physics ... In this "bouncing" cosmology, the universe contracted to a size about 50 orders of magnitude smaller than it is today. After the rebound, photons and other particles were born, marking the Big Bang. Near the rebound, the matter density was so high that small black holes formed from quantum fluctuations in the matter's density, making them viable candidates for dark matter.

"Small primordial black holes can be produced during the very early stages of the universe, and if they are not too small, their decay due to Hawking radiation [a hypothetical phenomenon of black holes emitting particles due to quantum effects] will not be efficient enough to get rid of them, so they would still be around now," Patrick Peter, director of research at the French National Centre for Scientific Research (CNRS), who was not involved in the study, told Live Science in an email. "Weighing more or less the mass of an asteroid, they could contribute to dark matter, or even solve this issue altogether."

The scientists' calculations show that this universe mode's properties, such as the curvature of space and the microwave background, match current observations, supporting their hypothesis.
"If this hypothesis holds, the gravitational waves generated during the black hole formation process might be detectable by future gravitational wave observatories, providing a way to confirm this dark matter generation scenario..."

"A new front has opened in the longstanding debate over how fast the universe is expanding," writes Science magazine: For years astronomers have argued over a gulf between the expansion rate as measured from galaxies in the local universe and as calculated from studies of the cosmic microwave background (CMB), the afterglow of the Big Bang. The disparity was so large and persistent that some astronomers thought the standard theory of the universe might have to be tweaked. But over the past week, results from NASA's new James Webb Space Telescope orbiting observatory suggest the problem may be more mundane: some systematic error in the strategies used to measure the distance to nearby galaxies.

"The evidence based on these data does not suggest the need for additional physics," says Wendy Freedman of the University of Chicago, who leads [the Carnegie-Chicago Hubble Program, or CCHP] that calculated the expansion rate from JWST data using three different galactic distance measurements and released the results on the arXiv preprint server. (The papers have not yet been peer reviewed.) The methods disagreed about the expansion rate, known as the Hubble constant, or H0, and two were close to the CMB prediction.
Specifically, the team used JWST to measure the distance to 10 local galaxies using three stars with a predictable brightness: Cepheids, the brightest red giant stars, and carbon stars. Science notes that the last two methods "agreed to about 1%, but differed from the Cepheid-based distance by 2.5% to 4%." Combining all three methods the team derived a value "just shy of 70 km/s per Mpc," according to the article — leading the University of Chicago's Freedman to say "There's something systematic in the measurements. Until we can establish unambiguously where the issue lies in the nearby universe, we can't be claiming that there's additional physics in the distant universe."

But the controversy continues, according to Adam Riess of Johns Hopkins University (leader of a team of Hubble Constant researchers known as SH0ES). Riess points out that other teams have used JWST to measure distances with all three methods separately and have come up with values closer to the original SH0ES result. He also questions why CCHP excluded data from telescopes other than JWST. "I don't see a compelling justification for excluding the data they do," he says.
Thanks to long-time Slashdot reader sciencehabit for sharing the article.

joshuark shares a report from The Verge: NASA researchers have successfully tested laser communications in space by streaming 4K video footage originating from an airplane in the sky to the International Space Station and back. The feat demonstrates that the space agency could provide live coverage of a Moon landing during the Artemis missions and bodes well for the development of optical communications that could connect humans to Mars and beyond. NASA normally uses radio waves to send data and talk between the surface to space but says that laser communications using infrared light can transmit data 10 to 100 times faster than radios. "ISS astronauts, cosmonauts, and unwelcomed commercial space-flight visitors can now watch their favorite porn in real-time, adding some life to a boring zero-G existence," adds joshuark. "Ralph Kramden, when contacted by Ouiji board, simply spelled out 'Bang, zoom, straight to the moon!'"

Long-time Slashdot reader theodp writes: Bob Newhart, whose stammering, deadpan unflappability carried him to stardom as a standup comedian and later in television and movies, has died at age 94. He remains best known for the television shows, "The Bob Newhart Show" (1972-78) and "Newhart" (1982-90), both of which were built around his persona as a reasonable man put-upon by crazies. A younger crowd may remember Newhart from his roles in the movie "Elf" (2003) and TV's "The Big Bang Theory" (2013-18).

Less known about Newhart is that he was an early Commodore PET owner, recalling for the LA Times in 2001: "I remember leafing through a copy of Popular Science magazine and seeing an ad for a Commodore computer that had 8- or 16 kilobytes [in 1977]. It had an awful-looking screen, and it was $795. I thought I'd better get one because I had sons who were going to be in high school and might want to know about computers. Later, I moved up to the 64 KB model and thought that was silly because it was more memory than I would ever possibly need.

"I got them for the kids and then found I was fascinated by them. The first ones had tape drives. You would get a program like a word processor, put the tape in and then walk away for about a half an hour while the computer loaded it. But the first time I used a spell checker and it corrected a word, I thought, 'We are getting close to God here."

An anonymous reader shares a report: Since the James Webb Space Telescope began operating two years ago, astronomers have been using it to leapfrog one another millions of years into the past, back toward the moment they call cosmic dawn, when the first stars and galaxies were formed. Last month, an international team doing research as the JWST Advanced Deep Extragalactic Survey, or JADES, said it had identified the earliest, most distant galaxy yet found -- a banana-shaped blob of color measuring 1,600 light-years across. It was already shining with intense starlight when the universe was in its relative infancy, at only 290 million years old, the astronomers said.

The new galaxy, known as JADES-GS-z14-0, is one of a string of Webb discoveries, including early galaxies and black holes, that challenge conventional models of how the first stars and galaxies formed. "This discovery proves that luminous galaxies were already in place 300 million years after the Big Bang and are more common than what was expected," the researchers wrote in a paper posted to an online physics archive. "Galaxy formation models will need to address the existence of such large and luminous galaxies so early in cosmic history," said the authors, who were led by Stefano Carniani, a professor at the university Scuola Normale Superiore in Pisa, Italy.

The galaxy was first spotted during a deep space survey with the Webb's Near Infrared Camera, one of the telescope's workhorse instruments. Within a patch of southern sky known as the Jades Origin Field, which is about a quarter of the size of a full moon, scientists found 11 galaxies that seemed to date from when the universe was less than 400 million years old -- far more than they had expected. Subsequent studies by Dr. Carniani and his colleagues with the telescope's infrared spectrograph revealed that the wavelength of light from JADES-GS-z14-0 had been stretched more than 15-fold by the expansion of the universe (a redshift of 14 to use astronomical jargon), similar to the way a siren's pitch becomes lower as it speeds away. That means light has been coming toward us for 13.5 billion years, since shortly after the universe began. (The universe is about 13.8 billion years old, according to cosmological calculations.) The light from the galaxy is spread over a diffuse region, which indicates that the glow was coming from stars, not the gullet of a black hole. Its brightness corresponded to the output of hundreds of millions of suns, an astonishing number to have formed and assembled in only 290 million years.