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Stephen Hawking's final scientific paper released

Black Hole Entropy and Soft Hair was completed in the days before the physicist’s death in March

Black holes and soft hair: why Stephen Hawking’s final work is important

Stephen Hawking’s final scientific paper has been released by physicists who worked with the late cosmologist on his career-long effort to understand what happens to information when objects fall into black holes.

The work, which tackles what theoretical physicists call “the information paradox”, was completed in the days before Hawking’s death in March . It has now been written up by his colleagues at Cambridge and Harvard universities and posted online .

Malcolm Perry, a professor of theoretical physics at Cambridge and a co-author on the paper, Black Hole Entropy and Soft Hair, said the information paradox was “at the centre of Hawking’s life” for more than 40 years.

The origins of the puzzle can be traced back to Albert Einstein. In 1915, Einstein published his theory of general relativity, a tour-de-force that described how gravity arises from the spacetime-bending effects of matter, and so why the planets circle the sun. But Einstein’s theory made important predictions about black holes too, notably that a black hole can be completely defined by only three features: its mass, charge, and spin.

Nearly 60 years later, Hawking added to the picture. He argued that black holes also have a temperature. And because hot objects lose heat into space, the ultimate fate of a black hole is to evaporate out of existence. But this throws up a problem. The rules of the quantum world demand that information is never lost. So what happens to all the information contained in an object – the nature of a moon’s atoms, for instance – when it tumbles into a black hole?

“The difficulty is that if you throw something into a black hole it looks like it disappears,” said Perry. “How could the information in that object ever be recovered if the black hole then disappears itself?”

In the latest paper, Hawking and his colleagues show how some information at least may be preserved. Toss an object into a black hole and the black hole’s temperature ought to change. So too will a property called entropy, a measure of an object’s internal disorder, which rises the hotter it gets.

The physicists, including Sasha Haco at Cambridge and Andrew Strominger at Harvard, show that a black hole’s entropy may be recorded by photons that surround the black hole’s event horizon, the point at which light cannot escape the intense gravitational pull. They call this sheen of photons “soft hair”.

“What this paper does is show that ‘soft hair’ can account for the entropy,” said Perry. “It’s telling you that soft hair really is doing the right stuff.”

It is not the end of the information paradox though. “We don’t know that Hawking entropy accounts for everything you could possibly throw at a black hole, so this is really a step along the way,” said Perry. “We think it’s a pretty good step, but there is a lot more work to be done.”

Days before Hawking died, Perry was at Harvard working on the paper with Strominger. He was not aware how ill Hawking was and called to give the physicist an update. It may have been the last scientific exchange Hawking had. “It was very difficult for Stephen to communicate and I was put on a loudspeaker to explain where we had got to. When I explained it, he simply produced an enormous smile. I told him we’d got somewhere. He knew the final result.”

Among the unknowns that Perry and his colleagues must now explore are how information associated with entropy is physically stored in soft hair and how that information comes out of a black hole when it evaporates.

“If I throw something in, is all of the information about what it is stored on the black hole’s horizon?” said Perry. “That is what is required to solve the information paradox. If it’s only half of it, or 99%, that is not enough, you have not solved the information paradox problem.

“It’s a step on the way, but it is definitely not the entire answer. We have slightly fewer puzzles than we had before, but there are definitely some perplexing issues left.”

Marika Taylor, professor of theoretical physics at Southampton University and a former student of Hawking’s, said: “Understanding the microscopic origin of this entropy – what are the underlying quantum states that the entropy counts? – has been one of the great challenges of the last 40 years.

“This paper proposes a way to understand entropy for astrophysical black holes based on symmetries of the event horizon. The authors have to make several non-trivial assumptions so the next steps will be to show that these assumptions are valid.”

Juan Maldacena, a theoretical physicist at Einstein’s alma mater, the Institute for Advanced Studies in Princeton, said: “Hawking found that black holes have a temperature. For ordinary objects we understand temperature as due to the motion of the microscopic constituents of the system. For example, the temperature of air is due to the motion of the molecules: the faster they move, the hotter it is.

“For black holes, it is unclear what those constituents are, and whether they can be associated to the horizon of a black hole. In some physical systems that have special symmetries, the thermal properties can be calculated in terms of these symmetries. This paper shows that near the black hole horizon we have one of these special symmetries.”

Stephen Hawking
Black holes

What Stephen Hawking’s Final Paper Says (And Doesn’t Say)

Before he died, renowned cosmologist Stephen Hawking submitted a paper, with co-author Thomas Hertog, to an as-yet-unknown journal. Hawking’s last known scientific writing, the paper deals with the concept of the multiverse and a theory known as cosmic inflation. Though the paper currently exists only in pre-print form , meaning it hasn’t completed the process of peer-review, it’s received a significant amount of coverage. “Stephen Hawking’s last paper,” after all, does have a bit of a mythological ring to it.

Stephen Hawking wrote a lot of papers, though. Most dealt with the same sort of heady concepts as his last, and few received such an inordinate amount of attention. Claims that the paper make predictions for the end of universe, or could prove the multiverse exists abound. But it’s worth remembering that the things Hawking thought and wrote about are abstract, they exist largely in the realm of theory. Even more well-known concepts like Hawking radiation have continued to elude scientists, so drawing solid conclusions from any one paper is difficult. Like many topics in theoretical physics, the ideas that Stephen Hawking pondered were so radical and far-out that we usually couldn’t even test them.

And even for one of the brightest minds of our time, the calculations are extremely complex. Hawking and Hertog describe their preliminary theory as a “toy model,” or one that significantly simplifies the real world to make the calculations easier. Such a model wouldn’t necessarily reflect the universe as we see it. No one said theoretical physics was easy.

Many Universes Stephen Hawking’s last paper is titled “A Smooth Exit from Eternal Inflation?” It tackles the idea of a multiverse, a vast collection of universes that exist simultaneously, though they’re spread out almost unimaginably far from each other. Multiverses arose, the theory goes, because of something called inflation. In the fractions of a second after our universe emerged, space-time expanded at an immense rate. As it did so, tiny quantum fluctuations expanded to become the large-scale features of the universe we observe today, and which serve as evidence that the theory might be true.

Under a variation of the theory that Hawking and Hertog work with, called eternal inflation, this inflation continues forever in most places, but, in some patches, it stops. Where it stops, universes form — our own and others, in a repeating process that never ends. In these universes, the laws of physics all look different, meaning constants we take for granted like the speed of light would vary between them.

“Eternal inflation creates an infinite number of patch universes, little bubble universes, all over the place with this inflating space between them,” says Will Kinney, a professor of physics at University at Buffalo College of Arts and Sciences.

But an infinite number of universes presents a problem to physicists. One of the most fundamental questions in science is why our universe looks the way it does. Why is the speed of light 186,282 miles per second? Determining the probability of our universe looking the way it does would help scientists get at the answer. Finding probabilities involving infinity is a useless exercise, though. What Hawking and Hertog have done, using a lot of complicated math, is to propose a way that we could define some boundaries on the kinds of universes that might exist.

“It’s like you have a bath full of lots and lots and lots of different kinds of soap bubbles and each soap bubble is a different universe, and there’s a huge variety of different soap bubbles of different shapes,” says Clifford Johnson, a professor in the Physics and Astronomy Department at the University of Southern California. “And what this model is suggesting is a mechanism by which maybe the variety of soap bubbles that are available is not as large as was thought.”

In addition, these universes might look a little more like ours, according to Katie Mack, an assistant professor of physics at North Carolina State University.

“The prediction is for … a smaller number of universes and they would have more in common with each other,” she says. “You could draw more of a straight line between the early universe and what we see today.”

Bringing Clarity If the kinds of universe that could possibly exist is finite, then scientists could begin to understand how and why our universe looks how it does today. Hawking’s paper does not tell us exactly what kind of universes might exist, nor does he definitively prove multiverse or cosmic inflation theories. As Kinney points out, Hawking and Hertog don’t even suggest any ways that we might be able to see evidence of the multiverse, meaning that their theory remains, for the moment, untestable.

The two rely on something called the holographic principle to conduct their work. It’s a way of reconciling quantum mechanics with gravity — the physics of the very large and the very small, as Mack, puts it. The holographic principle states that all of the information in a volume of space is contained in the boundary of the volume. In effect, it compresses a 3-D space into a 2-D space, and the end result is to make the calculations easier.

It’s something that many other researchers use in their work, and Johnson stresses that Hawking and Hertog’s paper, while intriguing, is simply another entry in the field.

“It’s two very good researchers adding a paper to the many very good papers that have been incrementally moving this framework of ideas,” Johnson says.

Hawking himself appears to have been still at work on the theory. Just weeks before his death, he submitted a newer version of the paper containing substantial changes. His co-author Hertog will surely continue to refine the work as well.

In the end, this paper is an interesting hypothesis about how our universe could look on the largest scale. It may not reshape our view of the cosmos — at least not yet — but it adds more intellectual firepower to our collective arsenal. And that’s probably what Stephen Hawking would have wanted.

This article originally appeared on Discovermagazine.com .

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Stephen Hawking’s final paper predicted the end of the world and revealed a parallel universe

STEPHEN Hawking submitted a research paper just weeks before he died hinting how scientists could find another universe.

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PROFESSOR Stephen Hawking submitted a research paper just two weeks before he died hinting how scientists could find another universe and predicting the end of the world.

The iconic physicist completed the groundbreaking research from his deathbed, said co-author professor Thomas Hertog.

It sets out the maths needed for a Star Trek-style space probe to find experimental evidence for the existence of a “multiverse” — the idea our cosmos is only one of many universes.

If such evidence had been found while he was alive, it might have put Hawking in line for the Nobel prize he had so desired, reports The Sunday Times.

“This was Stephen: to boldly go where Star Trek fears to tread,” said Hertog, professor of theoretical physics at KU Leuven University in Belgium.

“He has often been nominated for the Nobel and should have won it. Now he never can.”

REVEALED: Surprising things Stephen Hawking taught us

MORE: Stephen Hawking’s death shocks the world

Professor Stephen Hawking poses beside a lamp titled 'black hole light' by inventor Mark Champkins, presented to him during his visit to the Science Museum in London. Picture: AP

The paper confronts an issue that had bothered Hawking since the 1983 “no-boundary” theory he devised with James Hartle.

In his “no boundary theory” devised with James Hartle, the pair described how the Earth hurtled into existence during the Big Bang.

But the theory also predicted a multiverse meaning the phenomenon was accompanied by a number of other “Big Bangs” creating separate universes.

In his final paper, Hawking, along with the professor for theoretical physics at KU Leuven University in Belgium, explored how these universes could be found using a probe on a spaceship.

The paper also predicted how our universe would eventually fade into blackness as the stars run out of energy.

Such ideas are controversial among cosmologists. Professor Neil Turok, director of Canada’s Perimeter Institute and a friend of Hawking’s, but who disagreed with his ideas, said: “I remain puzzled as to why he found this picture interesting.”

Other scientists said Hawking’s work might represent the breakthrough that cosmology needs, especially because it was the first such theory that could be tested in experiments.

The paper, called “A Smooth Exit from Eternal Inflation”, had its latest revisions approved on March 4, 10 days before Hawking’s passed away.

The Sunday Times reports that the paper is due to be published by an unnamed “leading journal” after a review is complete.

Hertog also told The Sunday Times he met with Hawking in person to get final approval before submitting the paper.

WHY HAWKING DIDN’T WIN A NOBEL PRIZE

`Hawking won accolades from his peers for having one of the most brilliant minds in science, but he never got a Nobel prize because no one has yet proven his ideas.

The Nobel committee looks for proof, not big ideas. Hawking was a deep thinker — a theorist — and his musings about black holes and cosmology have yet to get the lockdown evidence that accompanies the physics prizes, his fellow scientists said.

“The Nobel prize is not given to the smartest person or even the one who makes the greatest contribution to science. It’s given to discovery,” said California Institute of Technology physicist Sean Carroll.

Stephen Hawking in Hawking had one final theory to share. Picture: MEGA

“Hawking’s best theories have not yet been tested experimentally, which is why he hasn’t won a prize.” Hawking has often been compared to Nobel laureate Albert Einstein, and he died on the 139th anniversary of Einstein’s birth. But Einstein’s Nobel wasn’t for his famed theory of general relativity. It was for describing the photoelectric effect, and only after it was verified by Robert Millikan, said Harvard astronomer Avi Loeb.

HOW HAWKING’S VOICE DEVELOPED

Hawking’s computer-generated voice was known to millions of people around the world, a robotic drawl that somehow enhanced the profound impact of the cosmological secrets he revealed.

The technology behind his means of communication was upgraded through the years, offering him the chance to sound less like a machine, but he insisted on sticking to the original voice because it had effectively become his own. The renowned theoretical physicist, who died last week aged 76, lost his ability to speak more than three decades ago after a tracheotomy linked to complications in the motor neurone disease he was diagnosed with at the age of 21.

He later told the BBC he had considered committing suicide by not breathing after the operation, but he said the “reflex to breathe was too strong”. Hawking started to communicate again using his eyebrows to indicate letters on a spelling card.

Astrophysicist Stephen Hawking is assisted off the tarmac at the Kennedy Space Center by his caregiver, Monica Guy, as he is applauded by members of the flight crew after completing a zero-gravity flight. Picture: AP

A Cambridge University colleague contacted a company which had developed a program to allow a user to select words using a hand clicker, according to a 2014 report in Wired magazine.

It was linked to an early speech synthesiser, which turned Hawking’s text into spoken language.

In 1997, PC chipmaker Intel Corp stepped in to improve Hawking’s computer-based communication system, and in 2014 it upgraded the technology to make it faster and easier for Hawking to communicate.

It used algorithms developed by SwiftKey, a British software company best known for its predictive text technology used in smartphones.

Hawking provided lectures and other texts to help the algorithm learn his language, and it could predict the word he wanted to use by just inputting 10-15 per cent of the letters.

But despite the upgrades to the software, one thing remained constant: the voice itself.

Hawking stuck with the sound produced by his first speech synthesiser made in 1986.

It helped cement his place in popular culture.

“I keep it because I have not heard a voice I like better and because I have identified with it,” he said in 2006.

Part of this report was originally published by The Sun and has been republished with permission.

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Professor Stephen Hawking’s final theory on the origin of the universe, which he worked on in collaboration with Professor Thomas Hertog from KU Leuven, has been published in the Journal of High Energy Physics .

We are not down to a single, unique universe, but our findings imply a significant reduction of the multiverse, to a much smaller range of possible universes. Stephen Hawking

The theory, which was submitted for publication before Hawking’s death earlier this year, is based on string theory and predicts the universe is finite and far simpler than many current theories about the big bang say.

Professor Hertog, whose work has been supported by the European Research Council, first announced the new theory at a conference at the University of Cambridge in July of last year, organised on the occasion of Professor Hawking’s 75 th birthday.

Modern theories of the big bang predict that our local universe came into existence with a brief burst of inflation – in other words, a tiny fraction of a second after the big bang itself, the universe expanded at an exponential rate. It is widely believed, however, that once inflation starts, there are regions where it never stops. It is thought that quantum effects can keep inflation going forever in some regions of the universe so that globally, inflation is eternal. The observable part of our universe would then be just a hospitable pocket universe, a region in which inflation has ended and stars and galaxies formed.

“The usual theory of eternal inflation predicts that globally our universe is like an infinite fractal, with a mosaic of different pocket universes, separated by an inflating ocean,” said Hawking in an interview last autumn. “The local laws of physics and chemistry can differ from one pocket universe to another, which together would form a multiverse. But I have never been a fan of the multiverse. If the scale of different universes in the multiverse is large or infinite the theory can’t be tested. ”

In their new paper, Hawking and Hertog say this account of eternal inflation as a theory of the big bang is wrong. “The problem with the usual account of eternal inflation is that it assumes an existing background universe that evolves according to Einstein’s theory of general relativity and treats the quantum effects as small fluctuations around this,” said Hertog. “However, the dynamics of eternal inflation wipes out the separation between classical and quantum physics. As a consequence, Einstein’s theory breaks down in eternal inflation.”

“We predict that our universe, on the largest scales, is reasonably smooth and globally finite. So it is not a fractal structure,” said Hawking.

The theory of eternal inflation that Hawking and Hertog put forward is based on string theory: a branch of theoretical physics that attempts to reconcile gravity and general relativity with quantum physics, in part by describing the fundamental constituents of the universe as tiny vibrating strings. Their approach uses the string theory concept of holography, which postulates that the universe is a large and complex hologram: physical reality in certain 3D spaces can be mathematically reduced to 2D projections on a surface.

Hawking and Hertog developed a variation of this concept of holography to project out the time dimension in eternal inflation. This enabled them to describe eternal inflation without having to rely on Einstein’ theory. In the new theory, eternal inflation is reduced to a timeless state defined on a spatial surface at the beginning of time.

“When we trace the evolution of our universe backwards in time, at some point we arrive at the threshold of eternal inflation, where our familiar notion of time ceases to have any meaning,” said Hertog.

Hawking’s earlier ‘no boundary theory’ predicted that if you go back in time to the beginning of the universe, the universe shrinks and closes off like a sphere, but this new theory represents a step away from the earlier work. “Now we’re saying that there is a boundary in our past,” said Hertog.

Hertog and Hawking used their new theory to derive more reliable predictions about the global structure of the universe. They predicted the universe that emerges from eternal inflation on the past boundary is finite and far simpler than the infinite fractal structure predicted by the old theory of eternal inflation.

Their results, if confirmed by further work, would have far-reaching implications for the multiverse paradigm. “We are not down to a single, unique universe, but our findings imply a significant reduction of the multiverse, to a much smaller range of possible universes,” said Hawking.

This makes the theory more predictive and testable.

Hertog now plans to study the implications of the new theory on smaller scales that are within reach of our space telescopes. He believes that primordial gravitational waves – ripples in spacetime – generated at the exit from eternal inflation constitute the most promising “smoking gun” to test the model. The expansion of our universe since the beginning means such gravitational waves would have very long wavelengths, outside the range of the current LIGO detectors. But they might be heard by the planned European space-based gravitational wave observatory, LISA, or seen in future experiments measuring the cosmic microwave background.

Reference: S.W. Hawking and Thomas Hertog. ‘ A Smooth Exit from Eternal Inflation? ’’ Journal of High-Energy Physics (2018). DOI: 10.1007/JHEP04(2018)147

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Stephen Hawking’s Final Paper: How to Escape From a Black Hole

In a study from beyond the grave, the theoretical physicist sings (mathematically) of memory, loss and the possibility of data redemption.

By Dennis Overbye

The cosmologist and pop-science icon Stephen Hawking, who died last March on Einstein’s birthday, spoke out from the grave recently in the form of his last scientific paper . Appropriately for a man on the Other Side, the paper is about how to escape from a black hole.

Cleansed of its abstract mathematics, the paper is an ode to memory, loss and the oldest of human yearnings, the desire for transcendence. As the doomed figure in Bruce Springsteen’s “Atlantic City” sings, “Everything dies, baby, that’s a fact, but maybe everything that dies someday comes back.”

Dr. Hawking was the manifestation of perseverance; stricken by Lou Gehrig’s disease, he managed to conquer the universe from a wheelchair. The fate of matter or information caught in a black hole is one that defined his career, and it has become one of the deepest issues in physics.

Black holes are objects so dense that, according to Einstein’s law of general relativity, not even light can escape. In 1974, Dr. Hawking turned these objects, and the rest of physics, inside-out. He discovered, to his surprise, that the random quantum effects that rule the microscopic world would cause black holes to leak and, eventually, explode and disappear.

In the fullness of time (which in many cases would be longer than the current age of the universe), all the mass and energy that had fallen into the hole would come back out. But, according to the classical Einstein equations, black holes are disturbingly simple; their only properties are mass, electrical charge and angular momentum. Every other detail about what falls into a black hole disappears from the universe’s memory banks. A black hole has no complications — no hair — the saying went.

So the fountain of matter and energy exiting a black hole would be random, Dr. Hawking emphasized in a paper in 1975. If you fell into one and came back out, you would lack all the details that had made you: male or female, blue eyes or brown, Yankee fan or Red Sox fan. The equation describing that fate is inscribed on Dr. Hawking’s tombstone, in Westminster Abbey, where it presumably will endure the ages.

That’s some kind of reincarnation. If nature can forget you, it could forget anything — a deathblow to the ability of science to reconstruct the past or predict the future. “It’s the past that tells us who we are,” Dr. Hawking told a conference at Harvard a couple years ago. “Without it, we lose our identity.”

In effect, Dr. Hawking maintained in his 1975 paper, the paradoxical quantum effects that Einstein had once dismissed, saying that God doesn’t play dice, were adding an extra forgetfulness to nature. “God not only plays dice,” Dr. Hawking wrote, “but he often throws them where they can’t be seen.”

Those were fighting words to other physicists; it was a basic tenet that the proverbial film of history can be run backward, to reconstruct what happened in, say, the collision of a pair of subatomic particles in a high-energy collider.

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Thirty years later Dr. Hawking recanted , but the argument went on. The “information paradox,” as it is known, remained at the center of physics because nobody, not even Dr. Hawking, could explain how black holes actually process the information that enters or exits them.

But scientists have been having a blast theorizing about the nature of space-time, information and memory. Some have suggested that you can’t even get into a black hole without being vaporized by a firewall of energy, let alone get back out.

Recent years have brought a glimmer of hope. Andrew Strominger of Harvard discovered that, when viewed from the right mathematical perspective — that of a light ray headed toward the infinite future — black holes are more complicated than we thought. They have what Dr. Strominger has called “soft hair,” in the form of those imaginary light rays, which can be ruffled, stroked, twisted and otherwise arranged by material coming into the black hole. In principle, this hair could encode information on the surface of the black hole, recording all those details that Einstein’s equations supposedly leave out .

Whether this is enough to save physics, let alone a person falling into a black hole, is what Dr. Hawking was working on in the years before he died.

“When I wrote my paper 40 years ago, I thought the information would pass into another universe,” he told me at the Harvard conference. Now, he said, it’s on the surface of the black hole. “The information will be re-emitted when the black hole evaporates.”

An Earthling’s Guide to Black Holes

Welcome to the place of no return — a region in space where the gravitational pull is so strong that not even light can escape it. This is a black hole.

Other experts, including Juan Maldacena of the Institute for Advanced Study in Princeton, have been more measured, saying that if soft hair does not solve the information paradox, it might at least help.

In his recent, posthumous report, which drew a flurry of press , Dr. Hawking and his colleagues endeavored to show how this optimistic idea could work. Besides Dr. Hawking, the paper’s authors were Dr. Strominger as well as Malcolm Perry and Sasha Haco of Cambridge University.

Dr. Strominger is hopeful that physicists one day will be able to understand black holes just by reading what is written in this soft hair.

“We didn’t prove it,” he said in an email. But, he added, they did succeed in showing how all the pieces could fit together: “If our guess is right, this paper will be of central importance. If not, it will be a technical footnote.”

Few of us, including Dr. Hawking, ever harbored the hope that solving the information paradox would bring back our parents, the dinosaurs or Joe DiMaggio from whatever was waiting in Atlantic City. Somewhere along the way we’ve all made some sort of accommodation with the idea that our personal timelines will come to an end, but we take some comfort in knowing that we will be remembered, and that our genes and books and names will carry on.

Last year’s Pixar/Disney movie “Coco,” which I happened to watch with my daughter recently, tells the story of a young Mexican boy who visits the Land of the Dead to find an ancestor who can help him in his quest to become a musician. The Land of the Dead is a lively place, but its denizens can only stay there, it turns out, as long as someone remembers them . When the memories vanish, so even do the animated skeletons

Some astronomers now say that even this pale version of salvation might be in jeopardy . A mysterious force called dark energy is speeding up the expansion of the universe. Someday, these experts say, if the expansion continues, making the galaxies fly away faster and faster, the rest of the universe will be permanently out of sight to us, and we will be forever out of sight of it. It would be as if we were surrounded by a black hole, into which all our information and memory were disappearing.

In our little bubble of the Milky Way, we might always remember Aretha and Cleopatra and Shakespeare and Hawking. But will the rest of the universe remember us?

Dennis Overbye joined The Times in 1998, and has been a reporter since 2001. He has written two books: “Lonely Hearts of the Cosmos: The Story of the Scientific Search for the Secret of the Universe” and “Einstein in Love: A Scientific Romance.” More about Dennis Overbye

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Stephen Hawking’s final scientific paper explores the mysteries of the multiverse—but it’s not a big deal

Hawking’s posthumous paper is more like a ruminative twist on multiverse theory, but that's just fine.

By Neel V. Patel | Published May 4, 2018 2:00 AM EDT

stephen hawking sits in front of a sign that says "Welcome Time Travelers"

Stephen Hawking’s death in March incited us all take a moment and think about the famed physicist’s impact on the scientific world, and the myriad ways his research affected the way we think about the universe. As it turns out, he wasn’t exactly done. Hawking’s final paper was finally published Wednesday, in the Journal of High Energy Physics , and while it’s not exactly the science-shattering work many outlets are reporting it to be , it still puts a pretty interesting, Hawking-esque spin on one of theoretical physics’ most discussed concepts: the multiverse.

The idea that multiple parallel universes exist originates out of inflation, the incredibly rapid expansion of the universe right after the Big Bang, over repeated bursts at speeds faster than light. Many scientists think during these bursts, the smallest blips in energy at the quantum level swelled into larger pockets of space-time—effectively entire individual universes which are possibly, conceivably found everywhere, within an ever-expanding larger multiverse that houses them .

Subscribing to that view essentially means assuming that, if the multiverse continues to inflate, individual universes are being created ad infinitum. For some, that’s a tough pill to swallow. And you can count Hawking and his co-author, Thomas Hertog from the University of Leuven in Belgium, among those skeptics.

So Hawking and Hertog created a framework for a simpler model of the multiverse that limits how many new universes could form, and ensures they adhere to the same laws of physics as our known universe. As opposed to older theories of multiverse that called for universes empty and full, volatile and boring, dead in an instant or with long lives ahead of them, these would be truer to the layman’s conception of parallel universes.

The new paper is sort of an update of the “no-boundary” proposal, something Hawking and American physicist James Hartle worked on in the 1980s. Using new mathematics derived from string theory that weren’t available in the 80s, Hawking and Hertog reach the conclusion our own universe is compatible with this idea, and that our multiverse is smaller than what we might expect from eternal inflation.

“Our model fits in nicely with the theory of inflation that says our universe underwent a very rapid period of expansion in its earliest stages,” says Hertog. “But our model goes radically against the prevailing extrapolation of inflation that led to a multiverse.”

It’s a pretty neat idea! It’s just not as exceptional as one outside the field might think at first glance. For one, it remains a theoretical paper; there’s no real way to test it out or make any sort of observations of this cosmology. In practical terms, it’s not practical at all. The original “no-boundary” proposal is speculative, and by extension so are these latest conclusions.

“The main conclusion of the paper is a conjecture and not proven mathematically,” says Avi Loeb, a theoretical physicist at Harvard University and a noted skeptic of inflation theory. “It is a stimulating but not revolutionary paper.”

Moreover, it’s not exactly a bombshell of a framework. “This paper is rather the culmination of a line of research we had been pursuing for a number of years driven to a large extent by the problems associated with the multiverse,” says Hertog. It’s not a flashbulb epiphany that just appeared in the authors’ brains in an instant, but rather an example of the slow burn of theoretical physics.

Like Loeb, Andrei Linde, a theoretical physics based at Stanford University and a pioneer of inflation theory, thinks it’s important to frame the findings as conjecture, not a final statement. But he does say they “may still be very significant, and, as many prolific statements made by Hawking, it may initiate productive work in this direction. This is an extremely complicated field of research, so it is very important to know Stephen Hawking’s thoughts on that.”

Loeb also finds it encouraging that the paper tampers down on the multiverse theory’s “problematic” suggestion that everything that can happen will happen an infinite number of times. “This theory is not falsifiable, because everything is possible,” he says. “The virtue of traditional physics is that its theories could be falsified by experiments. Science is a learning experience. If we give up on the possibility of falsifying our ideas, then we will not learn anything from experiments.”

But of course, Hawking and Hertog’s theory is also not falsifiable.

Instead, the excitement over this paper might really just be the fact that it’s Hawking’s last paper. The paper was long-available to the physics community to read and discuss, and only was only submitted to JHEP and accepted for publication on April 20. This new spike in interest is really just among the public, eager to see the last thing Hawking wrote. That certainly doesn’t diminish its impact, but it would be a bit foolish to make it out to be larger than it is.

It’s a bummer Hawking is no longer around to deliver something more exceptional. “Of course I have enormously enjoyed my collaboration with Hawking,” Hertog. “But I am sad Stephen is no longer with us today to celebrate the publication of this paper and to participate in our future adventures in cosmology.” He’s certainly far from the only one.

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What Stephen Hawking's Final Paper Says (And Doesn't Say)

Stephen Hawking wrote a lot of papers, though. Most dealt with the same sort of heady concepts as his last, and few received such an inordinate amount of attention. Claims that the paper make predictions for the end of universe, or could prove the multiverse exists abound. But it’s worth remembering that the things Hawking thought and wrote about are abstract, they exist largely in the realm of theory. Even more well-known concepts like Hawking radiation have continued to elude scientists, so drawing solid conclusions from any one paper is difficult.. Like many topics in theoretical physics, the ideas that Stephen Hawking pondered were so radical and far-out that we usually couldn’t even test them.

Many Universes

Stephen Hawking’s last paper is titled “A Smooth Exit from Eternal Inflation?” It tackles the idea of a multiverse, a vast collection of universes that exist simultaneously, though they’re spread out almost unimaginably far from each other. Multiverses arose, the theory goes, because of something called inflation. In the fractions of a second after our universe emerged, space-time expanded at an immense rate. As it did so, tiny quantum fluctuations expanded to become the large-scale features of the universe we observe today, and which serve as evidence that the theory might be true.

In addition, these universes might look a little more like ours, according to Katie Mack, an assistant professor of physics at North Carolina State University.

Bringing Clarity

If the kinds of universe that could possibly exist is finite, then scientists could begin to understand how and why our universe looks how it does today. Hawking’s paper does not tell us exactly what kind of universes might exist, nor does he definitively prove multiverse or cosmic inflation theories. As Kinney points out, Hawking and Hertog don’t even suggest any ways that we might be able to see evidence of the multiverse, meaning that their theory remains, for the moment, untestable.

It’s something that many other researchers use in their work, and Johnson stresses that Hawking and Hertog’s paper, while intriguing, is simply another entry in the field.

“It’s two very good researchers adding a paper to the many very good papers that have been incrementally moving this framework of ideas,” Johnson says.

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14 April 2023

Daily briefing: Stephen Hawking’s final theory

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JUICE mission to explore Jupiter's icy, ocean-bearing moons lifted off aboard Arianespace's Ariane 5 rocket at the Guiana Space Center in Kourou, French Guiana today (Jody Amiet/AFP via Getty Images)

JUICE spacecraft will visit Jupiter’s moons

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The European Space Agency’s spacecraft will be the first to orbit a moon of another planet when it circles Ganymede in search of a hidden ocean beneath the icy surface. A complex manoeuvre around the Sun and Earth will slingshot JUICE towards the outer Solar System. The mission will eventually end with a crash landing on Ganymede’s surface.

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Stephen Hawking’s final theory

The Universe is a four-dimensional membrane in a five-dimensional space , and a small part of a much vaster hidden reality. This is Stephen Hawking’s final theory, described in On the Origin of Time by Hawking’s last collaborator, Thomas Hertog. The book is a fascinating tour of cosmology, writes reviewer and science philosopher Robert Crease. In accessible language and with colourful anecdotes, Hartog describes how Hawking flip-flopped on whether the Universe had a beginning. Still, Hertog’s “Hawking worship” and his scorn for philosophy could be a source of irritation for readers, Crease says.

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Stephen Hawking's Final Paper Cuts the Multiverse Down to Size

Stephen Hawking's final paper, which aims to test a theory that proposes parallel universes, appeared today (May 2) in the Journal of High Energy Physics .

As Live Science reported at length in March, before the paper was peer-reviewed and officially published, it shares Hawking's final look at one of his earliest theories, the so-called "no-boundary proposal." This idea describes the conditions in the very early universe. Hawking and his co-author, Thomas Hertog, a physicist at the Catholic University of Leuven in Belgium, attempted to resolve thorny questions regarding the multiverse, or the idea that many universes exist side by side. Hertog called their conclusions a "departure" from the "no-boundary proposal" as Hawking originally presented it.

According to Hawking's "no-boundary proposal," before the Big Bang , when the entire universe was compressed into a single, infinitely small point, there was no directional time as we experience it. Time was a closed, boundary-free thing, like a sphere without edges. [ Stephen Hawking: A Physics Icon Remembered in Photos ]

Scientists later determined that this proposal implied something strange: that the multiverse is infinite, with endless, uncountable parallel universes existing alongside our own, Live Science previously reported. That wild situation presented a number of problems for science, most significantly that it rendered most basic scientific ideas about the multiverse impossible to test. (If there are infinitely many universes, then an experiment could make predictions about what the universe should look like — and there will be some universes out there that will match those predictions.)

"Hawking was not satisfied with this state of affairs," Hertog told Live Science in March. "'Let's try to tame the multiverse,' he told me a year ago. So, we set out to develop a method to transform the idea of a multiverse into a coherent, testable scientific framework."

Hawking's final paper suggests a framework for understanding the universe that would render the multiverse finite, countable and subject to meaningfully engagement via the tools of science .

There were some minor tweaks to the text of the paper as it appeared on the preprint server arXiv at the time of Hawking's death and its final published form, but they're minor and don't represent any fundamental differences in meaning.

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"There are no significant changes between versions 2 and 3," Hertog wrote in an email. "The paper represents indeed a departure from the no-boundary theory (as we write at the end)."

Physicists that Live Science interviewed previously said that while the idea is interesting, it isn't earth-shattering — in part because there's still no good way to prove it's true. In addition, as North Carolina State University cosmologist Katie Mack told Live Science at the time, the idea is not yet fully fleshed out.

"What they've done in this paper is to use what they call a toy model — it's not fully rigorous and complete," Mack said. "They admit that there's a lot more work to be done."

To get to that point, Mack said, physics will need to overcome some significant hurdles. Most importantly, they have to develop a thorough unification of the theories of gravity and quantum mechanics.

A PDF of the final, peer-reviewed version Hawking's final paper is available without a paywall on the preprint server arXiv. A digital version appeared on the journal's website on April 27.

Originally published on Live Science .

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Stephen Hawking predicted end of the world in final research paper submitted just two weeks before his death

Professor Stephen Hawking submitted a research paper just two weeks before his death suggesting how scientists could detect another universe and predicting the end of the world.

The world renowned physicist may have won a Nobel Prize for his final work which he completed from his deathbed, his co-author professor Thomas Hertog has said.

According to the Sunday Times, the theory questions an issue that had bothered Hawking, who died aged 76 on Wednesday, for 35 years.

In his “no boundary theory” devised with James Hartle, the pair described how the Earth hurtled into existence during the Big Bang.

But the theory also predicted a multiverse meaning the phenomenon was accompanied by a number of other “Big Bangs” creating separate universes.

In his final paper, Hawking, along with the professor for theoretical psychics at KU Leuven University in Belgium, explored how these universes could be found using a probe on a spaceship.

The paper also predicted how our universe would eventually fade into blackness as the stars run out of energy.

Hertog, who co-authored the paper named A Smooth Exit from Eternal Inflation, told the Sunday Times: “He has often been nominated for the Nobel and should have won it. Now he never can.”

The theory won mixed feedback from peers, some of whom questioned why Hawking found the ideas interesting.

Others suggested the potentially groundbreaking feedback was “what cosmology needed.”

Carlos Frenk, professor of cosmology at Durham University, agreed that it has previously been impossible to measure other universes.

The world-famous scientist died peacefully at his home in Cambridge in the early hours of Wednesday morning.

Professor Hawking's children, Lucy, Robert and Tim said in a statement: "We are deeply saddened that our beloved father passed away today.

"He was a great scientist and an extraordinary man whose work and legacy will live on for many years.”

Hawking was diagnosed with Motor Neurone Disease aged 22 and was told by doctors he had just years to live.

His death prompted an outpouring of support from scientists, politicians and celebrities alike.

Astrophysicist Neil deGrasse Tyson was one of the first to pay tribute.

Sharing a photo of himself and Hawking on Twitter, he said: "His passing has left an intellectual vacuum in his wake. But it's not empty. Think of it as a kind of vacuum energy permeating the fabric of spacetime that defies measure. Stephen Hawking, RIP 1942-2018."

Defence Minister Tobias Ellwood said Hawking was "an inspiration to us all, whatever our station in life, to reach for the stars".

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The Work of Stephen Hawking in Physical Review

To mark the passing of Stephen Hawking, we gathered together his 55 papers in Physical Review D and Physical Review Letters . They probe the edges of space and time, from "Black holes and thermodynamics” to "Wave function of the Universe."

85 citations

Occurrence of singularities in open universes, s. w. hawking, phys. rev. lett. 15 , 689 (1965) – published 25 october 1965, 94 citations, singularities in the universe, phys. rev. lett. 17 , 444 (1966) – published 22 august 1966, 717 citations, gravitational radiation from colliding black holes, phys. rev. lett. 26 , 1344 (1971) – published 24 may 1971, 50 citations, theory of the detection of short bursts of gravitational radiation, g. w. gibbons and s. w. hawking, phys. rev. d 4 , 2191 (1971) – published 15 october 1971, 924 citations, black holes and thermodynamics, phys. rev. d 13 , 191 (1976) – published 15 january 1976, 746 citations, path-integral derivation of black-hole radiance, j. b. hartle and s. w. hawking, phys. rev. d 13 , 2188 (1976) – published 15 april 1976, 1,463 citations, breakdown of predictability in gravitational collapse, phys. rev. d 14 , 2460 (1976) – published 15 november 1976, 2,133 citations, cosmological event horizons, thermodynamics, and particle creation, phys. rev. d 15 , 2738 (1977) – published 15 may 1977, 2,128 citations, action integrals and partition functions in quantum gravity, phys. rev. d 15 , 2752 (1977) – published 15 may 1977, 105 citations, quantum gravity and path integrals, phys. rev. d 18 , 1747 (1978) – published 15 september 1978, 394 citations, bubble collisions in the very early universe, s. w. hawking, i. g. moss, and j. m. stewart, phys. rev. d 26 , 2681 (1982) – published 15 november 1982, milestone 1,974 citations, wave function of the universe, phys. rev. d 28 , 2960 (1983) – published 15 december 1983, 468 citations, origin of structure in the universe, j. j. halliwell and s. w. hawking, phys. rev. d 31 , 1777 (1985) – published 15 april 1985, 134 citations, arrow of time in cosmology, phys. rev. d 32 , 2489 (1985) – published 15 november 1985, 300 citations, wormholes in spacetime, phys. rev. d 37 , 904 (1988) – published 15 february 1988, 113 citations, spectrum of wormholes, s. w. hawking and don n. page, phys. rev. d 42 , 2655 (1990) – published 15 october 1990, 16 citations, wormholes in string theory, alex lyons and s. w. hawking, phys. rev. d 44 , 3802 (1991) – published 15 december 1991, 506 citations, chronology protection conjecture, phys. rev. d 46 , 603 (1992) – published 15 july 1992, 89 citations, evaporation of two-dimensional black holes, phys. rev. lett. 69 , 406 (1992) – published 20 july 1992, 36 citations, kinks and topology change, phys. rev. lett. 69 , 1719 (1992) – published 21 september 1992, 51 citations, origin of time asymmetry, s. w. hawking, r. laflamme, and g. w. lyons, phys. rev. d 47 , 5342 (1993) – published 15 june 1993, 7 citations, quantum coherence in two dimensions, s. w. hawking and j. d. hayward, phys. rev. d 49 , 5252 (1994) – published 15 may 1994, 5 citations, superscattering matrix for two-dimensional black holes, phys. rev. d 50 , 3982 (1994) – published 15 september 1994, 305 citations, entropy, area, and black hole pairs, s. w. hawking, gary t. horowitz, and simon f. ross, phys. rev. d 51 , 4302 (1995) – published 15 april 1995, 71 citations, pair production of black holes on cosmic strings, s. w. hawking and simon f. ross, phys. rev. lett. 75 , 3382 (1995) – published 6 november 1995, 69 citations, probability for primordial black holes, r. bousso and s. w. hawking, phys. rev. d 52 , 5659 (1995) – published 15 november 1995, 39 citations, quantum coherence and closed timelike curves, phys. rev. d 52 , 5681 (1995) – published 15 november 1995, 157 citations, duality between electric and magnetic black holes, phys. rev. d 52 , 5865 (1995) – published 15 november 1995, 74 citations, virtual black holes, phys. rev. d 53 , 3099 (1996) – published 15 march 1996, 176 citations, pair creation of black holes during inflation, raphael bousso and stephen w. hawking, phys. rev. d 54 , 6312 (1996) – published 15 november 1996, 17 citations, evolution of near-extremal black holes, s. w. hawking and m. m. taylor-robinson, phys. rev. d 55 , 7680 (1997) – published 15 june 1997, 26 citations, loss of quantum coherence through scattering off virtual black holes, phys. rev. d 56 , 6403 (1997) – published 15 november 1997, 59 citations, trace anomaly of dilaton-coupled scalars in two dimensions, raphael bousso and stephen hawking, phys. rev. d 56 , 7788 (1997) – published 15 december 1997, 25 citations, models for chronology selection, m. j. cassidy and s. w. hawking, phys. rev. d 57 , 2372 (1998) – published 15 february 1998, 136 citations, (anti-)evaporation of schwarzschild–de sitter black holes, phys. rev. d 57 , 2436 (1998) – published 15 february 1998, 18 citations, bulk charges in eleven dimensions, phys. rev. d 58 , 025006 (1998) – published 12 june 1998, 15 citations, inflation, singular instantons, and eleven dimensional cosmology, s. w. hawking and harvey s. reall, phys. rev. d 59 , 023502 (1998) – published 7 december 1998, 114 citations, gravitational entropy and global structure, s. w. hawking and c. j. hunter, phys. rev. d 59 , 044025 (1999) – published 26 january 1999, 164 citations, nut charge, anti–de sitter space, and entropy, s. w. hawking, c. j. hunter, and don n. page, phys. rev. d 59 , 044033 (1999) – published 28 january 1999, 416 citations, rotation and the ads-cft correspondence, s. w. hawking, c. j. hunter, and m. m. taylor-robinson, phys. rev. d 59 , 064005 (1999) – published 1 february 1999, 23 citations, lorentzian condition in quantum gravity, phys. rev. d 59 , 103501 (1999) – published 29 march 1999, 166 citations, charged and rotating ads black holes and their cft duals, s. w. hawking and h. s. reall, phys. rev. d 61 , 024014 (1999) – published 20 december 1999, 355 citations, brane-world black holes, a. chamblin, s. w. hawking, and h. s. reall, phys. rev. d 61 , 065007 (2000) – published 25 february 2000, 197 citations, brane new world, s. w. hawking, t. hertog, and h. s. reall, phys. rev. d 62 , 043501 (2000) – published 29 june 2000, 52 citations, gravitational waves in open de sitter space, s. w. hawking, thomas hertog, and neil turok, phys. rev. d 62 , 063502 (2000) – published 31 july 2000, 129 citations, trace anomaly driven inflation, phys. rev. d 63 , 083504 (2001) – published 5 march 2001, 200 citations, living with ghosts, s. w. hawking and thomas hertog, phys. rev. d 65 , 103515 (2002) – published 9 may 2002, 28 citations, why does inflation start at the top of the hill, phys. rev. d 66 , 123509 (2002) – published 20 december 2002, 271 citations, information loss in black holes, phys. rev. d 72 , 084013 (2005) – published 18 october 2005, 45 citations, populating the landscape: a top-down approach, phys. rev. d 73 , 123527 (2006) – published 23 june 2006, no-boundary measure of the universe, james b. hartle, s. w. hawking, and thomas hertog, phys. rev. lett. 100 , 201301 (2008) – published 23 may 2008, 118 citations, classical universes of the no-boundary quantum state, phys. rev. d 77 , 123537 (2008) – published 25 june 2008, 33 citations, no-boundary measure in the regime of eternal inflation, james hartle, s. w. hawking, and thomas hertog, phys. rev. d 82 , 063510 (2010) – published 8 september 2010, 35 citations, local observation in eternal inflation, phys. rev. lett. 106 , 141302 (2011) – published 8 april 2011, featured in physics editors' suggestion 488 citations, soft hair on black holes, stephen w. hawking, malcolm j. perry, and andrew strominger, phys. rev. lett. 116 , 231301 (2016) – published 6 june 2016.

A black hole may carry “soft hair,” low-energy quantum excitations that release information when the black hole evaporates.

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Stephen Hawking's Final Paper Proposes Way to Detect the 'Multiverse'

Stephen Hawking's final research paper could help astronomers find evidence that our universe is just one among many in a larger " multiverse ," according to media reports.

The famed cosmologist, who died last week at the age of 76 , is lead author of a study called "A Smooth Exit from Eternal Inflation?" which was originally submitted to an unnamed journal last July. On March 4 — just 10 days before Hawking's death — his co-author, Thomas Hertog, a professor of theoretical physics at KU Leuven University in Belgium, submitted a revised version of the manuscript for further review, according to British newspaper The Sunday Times .

The inflation referenced in the paper's title is the incredible expansion of space-time theorized to have occurred in the first few moments after the Big Bang, which created the universe. Many physicists believe that this dramatic ballooning wasn't limited to our neck of the cosmic woods but rather happened repeatedly, spawning multiple universes — perhaps an infinite number of them.

"A consequence of inflation is that there should be a multitude of universes, but we have never been able to measure this," Carlos Frenk, a professor of cosmology at Durham University in England who's not involved in the new study, told The Sunday Times.

"The intriguing idea in Hawking’s paper is that [the multiverse] left its imprint on the background radiation permeating our universe and we could measure it with a detector on a spaceship," Frenk added. "These ideas offer the breathtaking prospect of finding evidence for the existence of other universes. This would profoundly change our perception of our place in the cosmos."

Not everyone is so enthusiastic about the paper's potential. For example, Neil Turok, the director of the Perimeter Institute for Theoretical Physics in Canada, told The Sunday Times, "I remain puzzled as to why [Hawking] found this picture interesting."

However it's ultimately received, the manuscript — which you can read for free at the online preprint site arXiv.org — is a reminder that Hawking was a deep thinker committed to tackling some of the universe's biggest mysteries. He will be missed a great deal, by his colleagues and the general public alike.

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You can read the full Sunday Times story here: https://www.thetimes.co.uk/article/stephen-hawkings-parting-shot-is-multi-cosmic-nbg0t6t9j

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Michael Wall is a Senior Space Writer with Space.com and joined the team in 2010. He primarily covers exoplanets, spaceflight and military space, but has been known to dabble in the space art beat. His book about the search for alien life, "Out There," was published on Nov. 13, 2018. Before becoming a science writer, Michael worked as a herpetologist and wildlife biologist. He has a Ph.D. in evolutionary biology from the University of Sydney, Australia, a bachelor's degree from the University of Arizona, and a graduate certificate in science writing from the University of California, Santa Cruz. To find out what his latest project is, you can follow Michael on Twitter.

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High Energy Physics - Theory

Title: black hole entropy and soft hair.

Abstract: A set of infinitesimal ${\rm Virasoro_{\,L}}\otimes{\rm Virasoro_{\,R}}$ diffeomorphisms are presented which act non-trivially on the horizon of a generic Kerr black hole with spin J. The covariant phase space formalism provides a formula for the Virasoro charges as surface integrals on the horizon. Integrability and associativity of the charge algebra are shown to require the inclusion of `Wald-Zoupas' counterterms. A counterterm satisfying the known consistency requirement is constructed and yields central charges $c_L=c_R=12J$. Assuming the existence of a quantum Hilbert space on which these charges generate the symmetries, as well as the applicability of the Cardy formula, the central charges reproduce the macroscopic area-entropy law for generic Kerr black holes.

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Read 55 of Stephen Hawking’s Research Papers for Free

Read Hawking's takes on black holes and string theory.

Over the course of his life, famed physicist Stephen Hawking wrote dozens of papers that explored the mysteries of time and space. From his 1966 thesis onward, he helped revolutionize the field of astrophysics and define what we know about the universe by diving into topics like string theory, black holes, and the Big Bang .

In the wake of his death last week, the American Physical Society (APS) has released 55 of his studies to “mark the passing of Stephen Hawking.” You can read them here . To fully understand the gravity of what’s going on here, you may want to brush up on your physics: There’s a reason Hawking is considered one of our preeminent geniuses. A huge number of them deal with wormholes and black holes , including this banger on black hole “soft hair,” or zero-energy particles that store information from the stars black holes gobble up.

Hawking helped confirm that black holes are birthed when a star collapses.

These 55 papers are found in the journals Physical Review D and Physical Review Letters , which are published by the APS. These studies, published from 1965 to 2016, the APS states on its site, “probe the edges of space and time.” The first paper published here, “Occurrence of Singularities in Open Universes,” was written a year before his infamous 1966 thesis on expanding universes and marks the start of his work that deals with the universe beginning from a singularity .

Some of the papers also are also an exercise in some fanciful titling by Hawking and his coauthors, including “ Brane New World ” and “ Living With Ghosts .” The latter deals with how gravitational dimensions affect ghost states — which are unphysical states on the wrong side of the kinetic term , and not actually ghosts .

When you’re done with the classics, you can move on over to a new hit titled “A Smooth Exit from Eternal Inflation?” This final paper from Hawking, co-authored with theoretical physicist Thomas Hertog, Ph.D., was submitted two weeks before Hawking’s death and currently exists in its preprint form .

While it doesn’t exactly predict the end of the universe, (something Hawking liked to discuss on in his free time), it does propose a new way to detect the ‘multiverse’: a mathematical road other scientists can explore, ensuring Hawking’s work lives on in the future.

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Stephen Hawking had one final warning for humanity before he died

Professor stephen hawking believed ai would bring about the end of humanity.

Britt Jones

It has been six years since global superstar of physics, Professor Stephen Hawking, died in 2018 and even he knew the dangers of generative AI.

Long before ChatGPT and automation systems became the daily norm for most of us, it was a lot harder to delegate and complete tasks.

But is it all it's cracked up to be?

A lot of people are agreeing that the rise of AI is going to turn out like a scene from I, Robot , but what will it look like for the workplace?

Hawking was way ahead of us with his prediction and even told the BBC back in 2012 that ‘the development of full artificial intelligence could spell the end of the human race’.

That’s pretty dark, Stephen .

But, he’s got a point.

At the time of his interview, AI was in its infancy, and Hawking could already see the power it might be able to have, especially its ability to surpass human intelligence.

Could AI spark the downfall of this world?

He continued: "It would take off on its own, and re-design itself at an ever-increasing rate.

"Humans, who are limited by slow biological evolution , couldn't compete, and would be superseded."

In 2015, he was also one of 100 experts to sign an open letter to the United Nations warning of the dangers of unchecked AI development and was joined by SpaceX founder Elon Musk in a bid to create stringent rules for AI .

Hawking warned that machines could take over.

Then, one year before he died in 2017, he warned mankind about the dangers of allowing AI to grow further during an interview with Wired magazine.

He said: “I fear AI may replace humans altogether."

Let’s be honest, if a man as smart as Hawking is telling us that AI is going to bring upon the end of times, we should probably listen to him.

At one point, he even suggested that we could become as dumb as rocks compared to machines if we don’t stay sharp in his book , Brief Answers to the Big Questions , published a few months after his death.

He wrote: "We may face an intelligence explosion that ultimately results in machines whose intelligence exceeds ours by more than ours exceeds that of snails.

"It’s tempting to dismiss the notion of highly intelligent machines as mere science fiction, but this would be a mistake - and potentially our worst mistake ever."

He’s not exactly wrong, though.

Stephen Hawking warned about the rise of AI.

If we look at the state of the digital era we are currently living in, AI has exploded at a rapid pace.

Not only can we now harness the use of OpenAI to create full-length educational articles, news pieces and scripts for films, it’s continuously learning by the information we feed it.

What will it be like in 20 years after being fed a wealth of knowledge and data?

A new text-to-video tool is also being developed called Sora, which spared another open letter in 2023 to push for a six-month pause on AI research.

I’m not saying it’s going to happen, but if the end of times is brought by a group of crazy smart machines thanks to AI development, I’m out.

Topics: Technology , Artificial Intelligence , Elon Musk , Stephen Hawking

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Stephen Hawking's final scientific paper released

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COMMENTS

Stephen Hawking's final scientific paper released
Wed 10 Oct 2018 18.30 EDT. Stephen Hawking's final scientific paper has been released by physicists who worked with the late cosmologist on his career-long effort to understand what happens to ...
Stephen Hawking's (almost) last paper: putting an end to the ...
When Stephen Hawking died on 14 March, the famed theoretical physicist had a few papers still in the works.Today, the Journal of High Energy Physics published his last work in cosmology—the science of how the universe sprang into being and evolved. (Other papers on black holes are still being prepared.) In the new paper, Hawking and Thomas Hertog, a theoretical physicist at the Catholic ...
What Stephen Hawking's Final Paper Says (And Doesn't Say)
Martin Hoscik/Shutterstock. [Update; May 1, 2018 — Stephen Hawking's final paper (" A smooth exit from eternal inflation? ") was published online on April 27, 2018, in The Journal of High ...
Stephen Hawking's Final Theory About Our Universe Has Just Been
Groundbreaking physicist Stephen Hawking left us one last shimmering piece of brilliance before he died: his final paper, detailing his last theory on the origin of the Universe, co-authored with Thomas Hertog from KU Leuven. ... The team's research has been published in the Journal of High Energy Physics, and can be read in full on arXiv. Good ...
Stephen Hawking: Final paper on parallel universes, end of the world
Stephen Hawking's final paper predicted the end of the world and revealed a parallel universe. STEPHEN Hawking submitted a research paper just weeks before he died hinting how scientists could ...
Taming the multiverse: Stephen Hawking's final theory about the big
The theory, which was submitted for publication before Hawking's death earlier this year, is based on string theory and predicts the universe is finite and far simpler than many current theories about the big bang say.. Professor Hertog, whose work has been supported by the European Research Council, first announced the new theory at a conference at the University of Cambridge in July of ...
Stephen Hawking's Final Paper: How to Escape From a Black Hole
The cosmologist and pop-science icon Stephen Hawking, who died last March on Einstein's birthday, spoke out from the grave recently in the form of his last scientific paper. Appropriately for a ...
Stephen Hawking's final scientific paper explores the mysteries of the
Stephen Hawking's death in March incited us all take a moment and think about the famed physicist's impact on the scientific world, and the myriad ways his research affected the way we think ...
What Stephen Hawking's Final Paper Says (And Doesn't Say)
Though the paper currently exists only in pre-print form, meaning it hasn't completed the process of peer-review, it's received a significant amount of coverage. "Stephen Hawking's last paper," after all, does have a bit of a mythological ring to it. Stephen Hawking wrote a lot of papers, though.
Daily briefing: Stephen Hawking's final theory
Stephen Hawking's final theory. The Universe is a four-dimensional membrane in a five-dimensional space, and a small part of a much vaster hidden reality. This is Stephen Hawking's final ...
Stephen Hawking's Final Paper Cuts the Multiverse Down to Size
A PDF of the final, peer-reviewed version Hawking's final paper is available without a paywall on the preprint server arXiv. A digital version appeared on the journal's website on April 27.
The Very Last Paper Stephen Hawking Worked on Has Just ...
Perry finished the work on the paper after Hawking's death in March 2018. He says it's a sign of progress in our understanding, but that there's still a long way to go. Some of Hawking's most significant research has been around black holes. The formula for the temperature of a black hole - the Hawking temperature - is inscribed on the ...
I Am An Astrophysicist. Here's What Stephen Hawking's Final Paper Was
On March 14, 2018, the most famous and celebrated scientist known to humanity, Stephen Hawking, died at the age of 76. He left a rich legacy behind in the fields of astrophysics and cosmology ...
Prof Stephen Hawking's multiverse finale
Prof Stephen Hawking's final research paper suggests that our Universe may be one of many similar to our own. The theory resolves a cosmic paradox of the late physicist's own making. It also ...
Stephen Hawking's Final Research Paper Predicted the End of the Universe
March 18, 2018. Flickr / x-ray delta one. Just two weeks before his death, renowned physicist Stephen Hawking submitted a research paper that suggests parallel universes and predicts the end of ...
Stephen Hawking predicted end of the world in final research paper
Professor Stephen Hawking submitted a research paper just two weeks before his death suggesting how scientists could detect another universe and predicting the end of the world.
Physical Review Journals
The Work of Stephen Hawking in. Physical Review. To mark the passing of Stephen Hawking, we gathered together his 55 papers in Physical Review D and Physical Review Letters. They probe the edges of space and time, from "Black holes and thermodynamics" to "Wave function of the Universe." 85 citations.
Stephen Hawking's Final Paper Proposes Way to Detect the 'Multiverse'
Hawking died at age 76 on March 14, 2018.(Image credit: Paul E. Alers/NASA) Stephen Hawking's final research paper could help astronomers find evidence that our universe is just one among many in ...
PDF Black Hole EntropyandSoft Hair arXiv:1810.01847v4 [hep-th] 13 Dec 2018
Stephen Hawking whose contributions to black hole physics remained vitally stimulating to the very end. This paper summarizes the status of our long-term project on large diﬀeomorphisms, soft hair and the quantum structure of black holes until the end of our time together. 1
[1810.01847] Black Hole Entropy and Soft Hair
Black Hole Entropy and Soft Hair. Sasha Haco, Stephen W. Hawking, Malcolm J. Perry, Andrew Strominger. A set of infinitesimal VirasoroL ⊗VirasoroR diffeomorphisms are presented which act non-trivially on the horizon of a generic Kerr black hole with spin J. The covariant phase space formalism provides a formula for the Virasoro charges as ...
Read 55 of Stephen Hawking's Research Papers for Free
This final paper from Hawking, co-authored with theoretical physicist Thomas Hertog, Ph.D., was submitted two weeks before Hawking's death and currently exists in its preprint form.
Stephen Hawking had one final warning for humanity before he died
Then, one year before he died in 2017, he warned mankind about the dangers of allowing AI to grow further during an interview with Wired magazine. He said: "I fear AI may replace humans ...