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James Bardeen, an expert in solving Einstein's equations, has died at the age of 83 – electriccitymagazine.ca

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James Bardeen, who helped elucidate the properties and behavior of black holes, paving the way for what has been called the golden age of black hole astrophysics, died on June 20 in Seattle. He was 83 years old.

His son William said the cause was cancer. Dr. Bardeen, professor emeritus of physics at the University of Washington, was living in a nursing home in Seattle.

Dr. Bardeen was a descendant of a famous family of physicists. His father is John Twice won the Nobel Prize in Physics, for the invention of the transistor and the theory of superconductivity; his brother, Williaman expert in quantum theory at the Fermi National Accelerator Laboratory in Illinois.

Dr. Bardeen was an expert in solving equations of Einstein’s general theory of relativity. This theory attributes what we call gravity to the curvature of spacetime with matter and energy. Its most mysterious and disturbing consequence has been the possibility of black holes, places so dense that they become endless one-way exit ramps from the universe, swallowing even light and time.

Dr. Bardeen will find the work of his life investigating those mysteries, as well as related mysteries about the evolution of the universe.

said Michael Turner, a cosmologist and professor emeritus at the University of Chicago, who described Dr. Bardeen as a “gentle giant.”

James Maxwell Bardeen was born in Minneapolis on May 9, 1939. His mother, Jane Maxwell Bardeen, was a zoologist and high school teacher. After his father’s business, the family moved to Washington, D.C.; To the Summit, NJ; Then to Champaign-Urbana, Illinois, where you graduate from University of Illinois High School Laboratory.

He attended Harvard University and graduated with a degree in physics in 1960, despite his father’s advice that biology was the wave of the future. “Everyone knows who my father is,” he said in an oral history interview recorded by the Federal University of Paraguay in 2020, adding that he did not feel the need to compete with him. “It was impossible anyway,” he said.

Work under the supervision of a physicist Richard Feynman And an astrophysicist William Fowler (who would both become Nobel Prize laureates), Dr. Bardeen received his Ph.D. He received his Ph.D. from the California Institute of Technology in 1965. His thesis was on the structure of supermassive stars millions of times the mass of the Sun. Astronomers are beginning to suspect that they are the source of the massive energies of quasars detected in the cores of distant galaxies.

After holding postdoctoral positions at the California Institute of Technology and the University of California, Berkeley, he joined the Department of Astronomy at the University of Washington in 1967. An enthusiastic hiker and mountaineer, he was drawn to the school by its easy access to the outdoors.

By then, what a Nobel Prize winner Cape Thorne, a professor at the California Institute of Technology, points out that the golden age of black hole research was in full swing, and Dr. Bardeen was swept up in international meetings. At one, in Paris in 1967, he met Nancy Thomas, a Connecticut high school teacher who was trying to improve her French. They married in 1968.

In addition to his son William, a senior vice president and chief strategy officer of The New York Times Company, and his brother William, Dr. Bardeen’s wife survives him, along with another son, David, and two grandchildren. Sister Elizabeth Gretke passed away in 2000.

attributed to him…Eduardo Braniff

Dr. Bardeen was a member of the National Academy of Sciences as well as his brother and father.

Although he was fast at math, Dr. Bardeen didn’t write faster than he spoke. William Price, a former student of Dr. Thorne now at the University of Texas, remembers being sent to Seattle to finish a paper Dr. Bardeen was supposed to write. Nothing is written. Dr. Bardeen’s wife then ordered the two to sit at opposite ends of the sofa with a sheet. Dr. Bardeen would write a sentence and pass the paper on to Dr. Press, who would either reject it or approve it and then put the pillow back. Dr. Bryce said that each sentence took a few minutes. It took them three days, but the paper was written.

One of the historical moments in those years was the month-long “Summer School” in Les Hoechs, France, in 1972 that included all the eminent black hole scientists. Dr. Bardeen was one of six invited speakers. It was during that meeting, Stephen Hawking from the University of Cambridge and Brandon Carternow from the Paris Observatory, wrote a landmark paper called “The Four Laws of Black Hole Mechanics,” which became a springboard for future work, including Dr. Hawking’s surprising calculation that black holes can leak and eventually explode.

In another famous account that same year, Dr. Bardeen deduced the shape and size of a black hole’s “shadow” as seen against a field of distant stars – a circle of light surrounding dark space.

Dr. Thorne said the shape was made famous by the Event Horizon Telescope observations of black holes in the galaxy M87 and at the center of the Milky Way, and by visualizations in the movie “Interstellar.”

Cosmology was among Dr. Bardeen’s other interests. In a 1982 paper, he, Dr. Turner and Paul Steinhardt of Princeton described how submicroscopic fluctuations in matter and energy density in the early universe would grow and give rise to the pattern of galaxies we see in the sky today.

Dr. Turner said, “Jim was glad we used his formalities, and he was sure we got it right.”

Dr. Bardeen transferred to Yale University in 1972. After four years, dissatisfied with the academic bureaucracy in the East and anxious abroad again, he returned to the University of Washington. Retired in 2006.

But it did not stop working. Dr. Thorne recounted a recent telephone conversation in which they recalled the hiking and camping trips they used to take with their families. In the same conversation, Dr. Bardeen described the last thoughts he had about what happens when a black hole evaporates, noting that it might turn into a white hole,

“This was one aspect of Jim in a nutshell, thinking deeply about physics in new creative ways until the end of his life,” Dr. Thorne wrote in an email.

“Reader. Infuriatingly humble coffee enthusiast. Future teen idol. Tv nerd. Explorer. Organizer. Twitter aficionado. Evil music fanatic.”

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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