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Category Archives: Quantum Physics
Faith: the Axis Upon Which the Wheel of Science Turns – aish.com Ponder, Philosophy, Featured – Aish
Posted: July 4, 2022 at 11:49 pm
Beneath every "fact" lies a series of assumptions that cannot be proven. Like it or not, even science requires a leap of faith.
Bill Nye, the 'Science Guy,' affirms that his "point of view is based on the facts of life" and not on faith-based "suppositions of life."1 For Nye, science is the only reliable, ultimate, unstoppable, and undeniable guide to truth and is faith-free. While scientific knowledge is the power that saves, faith, for the 'Science Guy,' is a weakness that only blinds. Nye believes that science alone can save the world and that faith must step aside to make way for the future. This is because, says Nye, people of faith "just can't handle the truth."2
But is science really faith free? Max Planck, Nobel laureate in physics and pioneer of quantum theory, thinks not. As Planck explains, "Anybody who has been seriously engaged in scientific work of any kind realizes that over the entrance to the gates of the temple of science are written the words: 'Ye must have faith.' It is a quality which the scientist cannot dispense with."3 For Planck, faith is the axis upon which the wheel of science turns. If one does not have faith, then one may not have science.
To illustrate Planck's insight, consider Nye's claim, "science is the only basis for truth." Is this idea, in and of itself, a truly scientific claim? Not at all. This claim is not open to experimental testing or to falsification. It is a claim that goes beyond the scientific method. There would thus be no purely scientific reason for accepting the truth of the above claim. Consequently, the claim that "science is the only basis for truth" would logically have to be false if it were true. In philosophy, this is what is called a self-defeating claim. At best, the proposition would be a paradox or a mystery, but otherwise, it is just self-referentially incoherent.
The 'Science Guy' Bill Nye is keen on trumpeting the "undeniable facts of science" as opposed to the "mere suppositions" of faith. But can science ever know anything for certain? Consider the confidently asserted certainty of "the central dogma of molecular biology," proclaimed by co-discoverer of the DNA double helix Francis Crick as a "fundamental biological law" in 1956. The central dogma holds that genetic information flows in only one directionfrom DNA (and RNA) to proteins, and never the other way around. This idea was believed to be a biological "law of nature" that operated without exception and was the conceptual basis for the Human Genome Project of the 1990s.
In the early 2000s, however, scientists increasingly witnessed phenomena that broke the biological law. They discovered that DNA can be edited as a result of life experience and that the way DNA is read depends on the surrounding environment. In other words, "the body keeps the score."4 With the discovery of what is today known as epigenetics, it became clear that information can be "transferred from a protein sequence back to the genome." Consequently, explains molecular biologist Eugene Koonin, "the Central Dogma of molecular biology is invalid as an 'absolute' principle: transfer of information from proteins (and specifically from protein sequences) to the genome does exist."5 The history of science is full of such cases where scientists have found exceptions to what were once viewed as exceptionless laws of Nature. How, then, can any scientific facts be undeniable?
Uncertainty in science may be the only scientific fact that we can ever be certain of. This is because science itself has discovered numerous areas where there are limits to what can be known through observation and experiment. Consider, for example, big bang cosmologythe leading scientific theory that describes the universe's origin, structure, and development. According to the standard big bang model, derived from Einstein's theory of general relativity and observational data, the universe began 13.7 billion years ago in a singularityan infinitely small point in which matter was infinitely compressed. Everything that physically exists, including matter, energy, space, and time, came into existence at the big bang singularity. Thus it makes no sense to speak of physical reality or even a "time before" this point.
Science itself has discovered numerous areas where there are limits to what can be known through observation and experiment.
The existence of an initial singularity of this sort represents a fundamental limit to the observational powers of science. Any "science" that speaks of the conditions that gave rise to the singularitysuch as an infinite multiverse or a quantum vacuum stateis not truly scientific because science can never test it. To assert that science will someday be able to adequately describe the conditions "before" or "beyond" the initial singularity is not a statement grounded in current science but, rather, in a philosophical faith.
While big bang cosmology reveals that there are limits to what scientists can know when studying the largest known phenomenon (the whole universe), quantum physics has also shown that there are limits to what scientists can know when studying the smallest conceivable objects (atoms and their constituent parts). Classical physics, which was the standard view of physics before 1900, said that it was possible simultaneously to know both the position and motion of a given particle with complete accuracy. While the precision of a classical physicist might, in practice, be limited only by the available technology, there was no reason in principle to expect that better technology would not eventually overcome such limits.
Quantum physics has also shown that there are limits to what scientists can know when studying the smallest conceivable objects (atoms and their constituent parts).
According to the standard view of current quantum physics, however, even perfect instruments cannot measure the location and velocity of a body simultaneously with impeccable precision. This fundamental limit on the accuracy of measurement is known as Heisenberg's uncertainty principle. As mathematical physicist John Barrow explains, "The quantum picture of reality introduces a new form of impossibility into our picture of the world. This impossibility replaces a past belief in unrestricted experimental investigation of Nature which was based upon a misconception of what existed to be measured."6 With quantum physics, says philosopher of science Michael Ruse, "we seem to have reached an outer point of what we can know."7
The renowned philosopher of science Karl Popper showed that the most exalted status that any scientific theory can reach is "not yet falsified, despite our best efforts."8 Scientific theories can never be verified, proven, or confirmed because an infinite number of experiments remain to be performed before all other possibilities can be ruled out. Consequently, scientific theories can only be falsified. For instance, it takes only one black swan to falsify the hypothesis that all swans are white. If a given hypothesis is to be counted as genuinely scientific, it must make testable predictions about the world that may be potentially refuted by later experimentation or possible observation.
The cornerstone of the scientific mind is its continuous openness to the possibility of being completely wrong. In order for science to function as science and make any progress in knowledge, science must always have humility as its foundation. If a given phenomenon appears to contradict our best-known science, then science must reserve judgment until scientists can find a way to investigate it adequately. Science, in principle, cannot make infallible pronouncements about what is possible. Indeed, our best theory of atomic physics (quantum mechanics) says that scientific accuracy can only deal in probabilities. Science, in both principle and practice, can never know anything for certain. Thus, while Bill Nye's "facts of life" may exist in theory, our most advanced current scientific knowledge of them is middling at bestand always will be.
Featured Image: Unsplash.com, Kinson Leung
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Faith: the Axis Upon Which the Wheel of Science Turns - aish.com Ponder, Philosophy, Featured - Aish
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James Bardeen, an Expert on Unraveling Einsteins Equations, Dies at 83 – The New York Times
Posted: at 11:49 pm
James Bardeen, who helped elucidate the properties and behavior of black holes, setting the stage for what has been called the golden age of black hole astrophysics, died on June 20 in Seattle. He was 83.
His son William said the cause was cancer. Dr. Bardeen, an emeritus professor of physics at the University of Washington, had been living in a retirement home in Seattle.
Dr. Bardeen was a scion of a renowned family of physicists. His father, John, twice won the Nobel Prize in Physics, for the invention of the transistor and the theory of superconductivity; his brother, William, is an expert on quantum theory at the Fermi National Accelerator Laboratory in Illinois.
Dr. Bardeen was an expert on unraveling the equations of Einsteins theory of general relativity. That theory ascribes what we call gravity to the bending of spacetime by matter and energy. Its most mysterious and disturbing consequence was the possibility of black holes, places so dense that they became bottomless one-way exit ramps out of the universe, swallowing even light and time.
Dr. Bardeen would find his lifes work investigating those mysteries, as well as related mysteries about the evolution of the universe.
Jim was part of the generation where the best and brightest went to work on general relativity, said Michael Turner, a cosmologist and emeritus professor 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 a high school teacher. Following his fathers work, the family moved to Washington, D.C.; to Summit, N.J.; and then to Champaign-Urbana, Ill., where he graduated from the University of Illinois Laboratory High School.
He attended Harvard and graduated with a physics degree in 1960, despite his fathers advice that biology was the wave of the future. Everybody knew who my father was, he said in an oral history interview recorded in 2020 by the Federal University of Paraguay, adding that he had not felt the need to compete with him. It was impossible, anyway, he said.
Working under the physicist Richard Feynman and the astrophysicist William A. Fowler (who would both become Nobel laureates), Dr. Bardeen obtained his Ph.D. from the California Institute of Technology in 1965. His thesis was about the structure of supermassive stars millions of times the mass of the sun; astronomers were beginning to suspect that they were the source of the prodigious energies of the quasars being discovered in the nuclei of distant galaxies.
After holding postdoctoral positions at Caltech and the University of California, Berkeley, he joined the astronomy department at the University of Washington in 1967. An avid hiker and mountain climber, he was drawn to the school by its easy access to the outdoors.
By then, what the Nobel laureate Kip Thorne, a professor at the California Institute of Technology, refers to as the golden age of black hole research was well underway, and Dr. Bardeen was swept up in international meetings. At one, in Paris in 1967, he met Nancy Thomas, a junior high school teacher in Connecticut who was trying to brush up on her French. They were married in 1968.
In addition to his son William, a senior vice president and the chief strategy officer of The New York Times Company, and his brother, William, Dr. Bardeens wife survives him, along with another son, David, and two grandchildren. A sister, Elizabeth Greytak, died in 2000.
Dr. Bardeen was a member of the National Academy of Sciences, as is his brother and as was his father.
Although he was speedy at math, Dr. Bardeen didnt write any faster than he spoke. William Press, a former student of Dr. Thornes now at the University of Texas, recalled being sent to Seattle to finish a paper that Dr. Bardeen and he were supposed to be writing. Nothing had been written. Dr. Bardeens wife then commanded the two to sit on opposite ends of a couch with a pad of paper. Dr. Bardeen would write a sentence and pass the pad to Dr. Press, who would either reject or approve it and then pass the pad back. Each sentence, Dr. Press said, took a few minutes. It took them three days, but the paper got written.
One of the epochal moments of those years was a monthlong summer school in Les Houches, France, in 1972 featuring all the leading black hole scholars. Dr. Bardeen was one of a half-dozen invited speakers. It was during that meeting that he, Stephen Hawking of Cambridge University and Brandon Carter, now of the Paris Observatory, wrote a landmark paper entitled The Four Laws of Black Hole Mechanics, which became a springboard for future work, including Dr. Hawkings surprise calculation that black holes could leak and eventually explode.
In another famous calculation the same year, Dr. Bardeen deduced the shape and size of a black holes shadow as seen against a field of distant stars a doughnut of light surrounding dark space.
That shape was made famous, Dr. Thorne said, by the Event Horizon Telescopes observations of black holes in the galaxy M87 and in the center of the Milky Way, and by visualizations in the movie Interstellar.
Another of Dr. Bardeens passions was cosmology. In a 1982 paper, he, Dr. Turner and Paul Steinhardt of Princeton described how submicroscopic fluctuations in the density of matter and energy in the early universe would grow and give rise to the pattern of galaxies we see in the sky today.
Jim was delighted that we used his formalism, Dr. Turner said, and was sure we got it right.
Dr. Bardeen moved to Yale in 1972. Four years later, unhappy with the academic bureaucracy in the East and yearning for the outdoors again, he moved back to the University of Washington. He retired in 2006.
But he never stopped working. Dr. Thorne recounted a recent telephone conversation in which they reminisced about the hiking and camping trips they used to take with their families. In the same conversation, Dr. Bardeen described recent ideas he had about what happens as a black hole evaporates, suggesting that it might change into a white hole.
That was one aspect of Jim in a nutshell, Dr. Thorne wrote in an email, thinking deeply about physics in creative new ways right up to the end of his life.
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Mjlnir: The physics that could stop the unworthy from wielding Thor’s hammer – BBC Science Focus Magazine
Posted: at 11:49 pm
According to comic book legend, the hammer of Thor, Mjlnir, can only be lifted by those who are deemed worthy enough to wield it. Now, with Thor: Love And Thunder due for release, this has inevitably led to questions.
What makes someone worthy? How does the hammer stop the likes of the Hulk from lifting it? And if even the Hulk cannot lift it, how much must it weigh? Its a debate so enduring that it made its way into 2015s Avengers: Age Of Ultron, where all of the Avengers took turns trying (and failing) to lift the hammer off a table. The handles imprinted, right? suggests an annoyed Tony Stark. Like a security code?
James Kakalios, a physics professor at the University of Minnesota, and author of The Physics Of Superheroes, has spent more time than most thinking about Thors hammer. So much so, in fact, that his theory for how it works was cited by Bruce Banner himself in an issue of the 2012 comic The Indestructible Hulk. For a start, Kakalios suggests that Stark wasnt that far off with his idea of the hammers handle featuring a fingerprint scanner.
The science of the Asgardians is so advanced that to us it would seem like magic, he says. It makes sense that Mjlnir would possess a form of artificial intelligence that, when you grab the handle, uses some sort of biosensor to scan whether youre worthy. He uses a scene from the first Thor movie to illustrate his point. Odin banishes Thor, after whispering to Mjlnir, whoever holds this hammer, if they be worthy, shall possess the power of Thor. So basically Odin has administrator rights to rewrite the hammers operating code.
But even if that was true, how does Mjlnir also repel the unworthy by making itself impossible to lift? Kakalioss Bruce-Banner-approved theory pivots around gravitons. These are fundamental particles that have not yet been confirmed to exist on Earth, but could exist in the scientifically advanced society of Asgard.
No one has observed a graviton yet, he says, but it is believed to be the quantum mediator of the gravitational force; much like photons of light are the quantum excitation of the electromagnetic field.
Natalie Portman and Chris Hemsworth in Thor: Love and Thunder Disney/Marvel
Kakalioss theory is that when Mjlnir is grabbed by someone it has deemed unworthy, it emits gravitons to make the hammer a heavier weight than the individual can lift. This, Kakalios says, explains why the hammer does not fall through the table in Avengers: Age Of Ultron because it is able to use gravitons to adjust its weight and nullify whatever force is being exerted on it.
It will only emit those excess gravitons while youre trying to lift it, says Kakalios. Lets say the hammer weighs 40 pounds. It exerts a force of 40 pounds on the table and the table pushes back with a weight of 40 pounds. So the hammer doesnt move. You then try to lift it off the table with a force of 80 pounds. You should be able to because 80 up is greater than 40 down.
"But if the hammer at that moment knows how much force youre exerting, it could emit gravitons so now it weighs 80 pounds. Your 80 and its 80 balance out. The moment you let go, it stops emitting the gravitons and goes back to weighing 40 pounds, meaning it can sit on the table just fine.
Or, of course, it could just be magic.
Verdict: Mjlnirs traits might be weird, but it can all be explained by Asgardian physics... even if their physics is different from ours.
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Cosmic phenomenon predicted by Einstein could shatter physics as we know it – Inverse
Posted: at 11:49 pm
On February 11, 2016, researchers at the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced the detection of gravitational waves for the first time. As predicted by Einsteins General Theory of Relativity, these waves result from massive objects merging, which causes ripples through spacetime that can be detected.
Since then, astrophysicists have theorized countless ways that gravitational waves could be used to study physics beyond the standard models of gravity and particle physics and advance our understanding of the Universe.
To date, gravitational waves have been proposed as a means of studying dark matter, the interiors of neutron stars and supernovae, mergers between supermassive black holes, and more.
Whats new In a recent study, a team of physicists from the University of Amsterdam and Harvard University has proposed a way where gravitational waves could be used to search for ultralight bosons around rotating black holes. This method could not only offer a new way to discern the properties of binary black holes but could lead to the discovery of new particles beyond the Standard Model.
The research was conducted by researchers at the Gravitation Astroparticle Physics Amsterdam (GRAPPA), at the University of Amsterdam, with support provided by the Center for Theoretical Physics and the National Center for Theoretical Sciences at the University of Taipei (Taiwan), and Harvard University. The paper that describes their work, titled Sharp Signals of Boson Clouds in Black Hole Binary Inspirals, recently appeared in the Physical Review Letters.
Its a well-known fact that normal matter will infall toward black holes over time, which will form an accretion disk around its outer edge (aka. Event Horizon). This disk will be accelerated to incredible speeds, causing the material within to become super-heated and release tremendous amounts of radiation while slowly being accreted onto the black holes face. However, for the past few decades, scientists have observed that black holes will shed some of their mass through a process called superradiance.
This phenomenon was studied by Stephen Hawking, who described how rotating black holes would throw off radiation that would appear real to a nearby observer, but virtual to a distant one. In the process of transferring this radiation from one reference frame to another, the acceleration of the particle itself would cause it to transform from virtual to real. This exotic form of energy, known as Hawking Radiation, will form clouds of low-mass particles around a black hole. This leads to a gravitational atom, so-named because they resemble ordinary atoms (clouds of particles surrounding a core)
While scientists know that this phenomenon occurs, they also understand that it could only be explained through the existence of a new ultralight particle that exists beyond the Standard Model. This was the focus of the new paper, where lead author Daniel Baumann (GRAPPA and the University of Taipei) and his colleagues examined how superradiance causes unstable clouds of ultralight bosons to form around black holes spontaneously. In addition, they suggest that the similarities between gravitational and regular atoms go deeper than their structure.
In short, they suggest that binary black holes could cause particles in their clouds to become ionized via the photoelectric effect. As described by Einstein, this occurs when electromagnetic energy (such as light) makes contact with a material, causing it to emit excited electrons (photoelectrons). When applied to a binary black hole, Baumann and his colleagues show how clouds of ultralight bosons could absorb the orbital energy of a black hole companion. This would cause some of the bosons to become ejected and accelerated, evident from the black holes associated gravitational wave signals.
Lastly, they demonstrated how this process could dramatically alter the evolution of binary black holes by reducing the time it takes for the objects to merge. As they state:
These kinks, they argue, will be discernible to next-generation gravitational wave interferometers like the Laser Interferometer Space Antenna (LISA). This process could be used to discover an entirely new class of ultralight particles and provide direct information about the mass and state of gravitational atom clouds. In short, the ongoing studies of gravitational waves using more sensitive interferometers could reveal exotic physics that advance our understanding of black holes and lead to new breakthroughs in particle physics.
This is one of many possibilities that have been ventured thanks to the revolution taking place with gravitational wave astronomy. In the coming years, astrophysicists hope to use them to probe the most extreme environments in the Universe, like black holes and neutron stars. They also hope that primordial gravitational waves will reveal things about the early Universe, help resolve the mystery of the matter/anti-matter imbalance, and lead to a quantum theory of gravity (aka. a Theory of Everything).
This article was originally published on Universe Today by Matt Williams. Read the original article here.
LEARN SOMETHING NEW EVERY DAY.
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Sunday Social: Debut try, a kick to win and heartwarming gestures – Yahoo Eurosport UK
Posted: at 11:49 pm
Credit: PA Images
It is time for Planet Rugbys Sunday Social, your quirky recap of the serious and not so serious talking points from the past weeks action.
Kicking off with an outrageous debut try from Henry Arundell! Everything this youngster touches seems to turn to gold. It looks like England has another Test superstar loading. Brilliant stuff from the London Irish speedster!
The leg drive has to come from somewhere! A humorous take on the source of Arundells power. Scandalously exciting debut indeed.
Wow! An aggressive push to the head from Jonny Hill on Wallaby Darcy Swain. How on earth has this gone unnoticed by the match officials? It truly was a robust clash between the two old rivals.
The heat between the two continued until Swain got himself a red card for a headbutt. It is never nice to see these kinds of scuffles on the pitch. Unnecessary and ill-disciplined. Poor from both parties here.
As soon as Englands Maro Itoje started screaming at the Australian line-out, the meme creators of the internets underbelly kicked into overdrive! A good laugh from Squidge Rugby, who has his take on a strange moment.
Another one! Sorry, Itoje, but there was no other outcome. The image sums up Englands second half. Springboks supporters probably felt the same about their first half at Loftus Versfeld against Wales.
ICE in his veins. Springbok Damian Willemse steps up after the hooter and nails the penalty to win. That is incredible composure for a player that has not kicked much at goal all seasonpure class.
If anyone has forgotten how ridiculously talented All Black Ardie Savea is, here is your reminder. What a game by the number eight scoring a brace! World-class performer.
What a heartwarming moment! A lovely lady hands the Wallabies captain Michael Hooper a chocolate bar for his efforts on the field. A kind and warm gesture.
Brothers in arms! Always lovely to see two siblings representing their country together. Paolo and Alessandro Garbisi lining up for Italy! What a moment that is for the Garbisi family.
Story continues
The Champions Cup draw was completed this week, but you will need a Quantum Physics degree to make sense of what is going on. Surely there must be a more simple method? Is this the best they can do?
Remembering an iconic moment for the Lions. Who does not like seeing Israel Folau carried like a naughty child by George North? Immense power is showcased in a bizarre moment in rugby.
Leicester Tigers assistant coach Kevin Sinfield took an old friend and teammate Rob Burrow, who suffers from Motor Neurone Disease, on a 10-kilometre run to raise money for the cause. Fantastic stuff from the pair who have already raised a great deal of money. Rugby is more than just a game. The camaraderie and brotherhood transcend the sport.
READ MORE:Eddie Jones: Darcy Swain red-card influenced refereeing decisions to even the game up
The article Sunday Social: Debut try, a kick to win and heartwarming gestures appeared first on Planetrugby.com.
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Sunday Social: Debut try, a kick to win and heartwarming gestures - Yahoo Eurosport UK
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Fireworks are only possible because of quantum physics – Big Think
Posted: June 30, 2022 at 9:29 pm
This Monday, July 4, 2022, is remarkable for a number of reasons. It happens to be aphelion: the day where the Earth is at its most distant from the Sun as it revolves through the Solar System in its elliptical orbit. Its the 246th anniversary of when the United States officially declared independence from, and war on, Britain. And it marks the annual date where the wealthiest nation in the world sets off more explosivesin the form of fireworksthan any other.
Whether youre an amateur hobbyist, a professional installer, or simply a spectator, fireworks showsare driven by the same laws of physicsthat govern all of nature. Individual fireworks all contain the same four component stages: launch, fuse, burst charges, and stars. Without quantum physics, not a single one of them would be possible. Heres the science behind how every component of these spectacular shows works.
The anatomy of a firework consists of a large variety of elements and stages. However, the same four basic elements are the same across all types and styles of fireworks: the lift charge, the main fuse, a burst charge, and stars. Variations in the diameter of the launch tube, the length of the time-delay fuse, and the height of the fireworks are all necessary to ignite the stars with the proper conditions during the break.
The start of any firework is the launch aspect: the initial explosion that causes the lift. Ever sincefireworks were first inventedmore than a millennium ago, the same three simple ingredients have been at the heart of them: sulfur, charcoal, and a source of potassium nitrate. Sulfur is a yellow solid that occurs naturally in volcanically active locations, while potassium nitrate is abundant in natural sources like bird droppings or bat guano.
Charcoal, on the other hand, isnt the briquettes we commonly use for grilling, but the carbon residue left over from charring (or pyrolyzing) organic matter, such as wood. Once all the water has been removed from the charcoal, all three ingredients can be mixed together with a mortar and pestle. The fine, black powder that emerges is gunpowder, already oxygen-rich from the potassium nitrate.
The three main ingredients in black powder (gunpowder) are charcoal (activated carbon, at left), sulfur (bottom right) and potassium nitrate (top right). The nitrate portion of the potassium nitrate contains its own oxygen, which means that fireworks can be successfully launched and ignited even in the absence of external oxygen; they would work just as well on the Moon as they do on Earth.
With all those ingredients mixed together, theres a lot of stored energy in the molecular bonds holding the different components together. But theres a more stable configuration that these atoms and molecules could be rearranged into. The raw ingredientspotassium nitrate, carbon, and sulfurwill combust (in the presence of high-enough temperatures) to form solids such as potassium carbonate, potassium sulfate, and potassium sulfide, along gases such as carbon dioxide, nitrogen, and carbon monoxide.
All it takes to reach these high temperatures is a small heat source, like a match. The reaction is a quick-burning deflagration, rather than an explosion, which is incredibly useful in a propulsion device. The rearrangement of these atoms (and the fact that the fuel contains its own oxygen) allows the nuclei and electrons to rearrange their configuration, releasing energy and sustaining the reaction. Without the quantum physics of these rearranged bonds, there would be no way to release this stored energy.
The Macys Fourth of July fireworks celebration that takes place annually in New York City displays some of the largest and highest fireworks you can find in the United States of America and the world. This iconic celebration, along with all the associated lights and colors, is only possible because of the inescapable rules of quantum mechanics.
When that first energy release occurs, conventionally known as the lift charge, it has two important effects.
The upward acceleration needs to give your firework the right upward velocity to get it to a safe height for explosion, and the fuse needs to be timed appropriately to detonate at the peak launch height. A small fireworks show might have shells as small as 2 inches (5 cm) in diameter, which require a height of 200 feet (60 m), while the largest shows (like the one by the Statue of Liberty in New York) have shells as large as 3 feet (90 cm) in diameter, requiring altitudes exceeding 1000 feet (300 m).
Different diameter shells can produce different sized bursts, which require being launched to progressively higher altitudes for safety and visibility reasons. In general, larger fireworks must be launched to higher altitudes, and therefore require larger lift charges and longer fuse times to get there. The largest fireworks shells exceed even the most grandiose of the illustrations in this diagram.
The fuse, on the other hand, is the second stage and will be lit by the ignition stage of the launch.Most fusesrely on a similar black powder reaction to the one used in a lift charge, except the burning black powder core is surrounded by wrapped textile coated with either wax or lacquer. The inner core functions via the same quantum rearrangement of atoms and electron bonds as any black powder reaction, but the remaining fuse components serve a different purpose: to delay ignition.
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The textile material is typically made of multiple woven and coated strings. The coatings make the device water resistant, so they can work regardless of weather. The woven strings control the rate of burning, dependent on what theyre made out of, the number and diameter of each woven string, and the diameter of the powder core. Slow-burning fuses might take 30 seconds to burn a single foot, while fast-burning fuses can burn hundreds of feet in a single second.
The three main configurations of fireworks, with lift charges, fuses, burst charges and stars all visible. In all cases, a lift charge launches the firework upward from within a tube, igniting the fuse, which then burns until it ignites the burst charge, which heats and distributes the stars over a large volume of space.
The third stage, then, is the burst charge stage, which controls the size and spatial distribution of the stars inside. In general the higher you launch your fireworks and the larger-diameter your shells are, the larger your burst charge will need to be to propel the insides of the shell outward. In general, the interior of the firework will have a fuse connected to the burst charge, which is surrounded by the color-producing stars.
Theburst chargecan be as simple as another collection of black powder, such as gunpowder. But it could be far more complex, such as the much louder and more impressiveflash powder, or a multi-stage explosive that sends stars in multiple directions. By utilizing different chemical compounds that offer different quantum rearrangements of their bonds, you can tune your energy release, the size of the burst, and the distribution and ignition times of the stars.
Differently shaped patterns and flight paths are highly dependent on the configuration and compositions of the stars inside the fireworks themselves. This final stage is what produces the light and color of fireworks, and is where the most important quantum physics comes into play.
But the most interesting part is that final stage: where the stars ignite. The burst is what takes the interior temperatures to sufficient levelsto create the light and colorthat we associate with these spectacular shows. The coarse explanation is that you can take different chemical compounds, place them inside the stars, and when they reach a sufficient temperature, they emit light of different colors.
This explanation, though, glosses over the most important component: the mechanism of how these colors are emitted. When you apply enough energy to an atom or molecule, you can excite or even ionize the electrons that conventionally keep it electrically neutral. When those excited electrons then naturally cascade downward in the atom, molecule or ion, they emit photons, producing emission lines of a characteristic frequency. If they fall in the visible portion of the spectrum, the human eye is even capable of seeing them.
Whether in an atom, molecule, or ion, the transitions of electrons from a higher energy level to a lower energy level will result in the emission of radiation at a very particular wavelength. This produces the phenomenon we see as emission lines, and is responsible for the variety of colors we see in a fireworks display.
What determines which emission lines an element or compound possesses? Its simply the quantum mechanics of the spacing between the different energy levels inherent to the substance itself. For example, heated sodium emits a characteristic yellow glow, as it has two very narrow emission lines at 588 and 589 nanometers. Youre likely familiar with these if you live in a city, as most of those yellow-colored street lamps you see are powered by elemental sodium.
As applied to fireworks, there are a great variety of elements and compounds that can be utilized to emit a wide variety of colors. Different compounds of Barium, Sodium, Copper and Strontium can produce colors covering a huge range of the visible spectrum, and the different compounds inserted in the fireworks stars are responsible for everything we see. In fact,the full spectrum of colors can be achievedwith just a handful of conventional compounds.
The interior of this curve shows the relationship between color, wavelength, and temperature in chromaticity space. Along the edges, where the colors are most saturated, a variety of elements, ions, and compounds can be shown, with their various emission lines marked out. Note that many elements/compounds have multiple emission lines associated with them, and all of these are used in various fireworks. Because of how easy it is to create barium oxide in a combustion reaction, certain firework colors, such as forest green and ocean green, remain elusive.
Whats perhaps the most impressive about all of this is that the color we see with the human eye is not necessarily the same as the color emitted by the fireworks themselves. For example, if you were to analyze the light emitted by a violet laser, youd find that the photons emerging from it were of a specific wavelength that corresponded to the violet part of the spectrum.
The quantum transitions that power a laser always result in photons of exactly the same wavelength, and our eyes see them precisely as they are, with the multiple types of cones we possess responding to that signal in such a way that our brain responds to construct a signal thats commensurate with the light possessing a violet color.
A set of Q-line laser pointers showcase the diverse colors and compact size that now are commonplace for lasers. By pumping electrons into an excited state and stimulating them with a photon of the desired wavelength, you can cause the emission of another photon of exactly the same energy and wavelength. This action is how the light for a laser is first created: by the stimulated emission of radiation.
But if you look at that same color that appears as violet not from a monochromatic source like a laser, but from your phone or computer screen, youll find that there are no intrinsically violet photons striking your eyes at all! Instead,as Chad Orzel has noted in the past,
Our eyes construct what we perceive as color from the response of three types of cells in our retina, each sensitive to light of a particular range of colors. One is most sensitive to blue-ish light (short wavelength), one is most sensitive to red light (long wavelength), and the third to a sort of yellow-green. Based on how strongly each of these cells responds to incoming light, our brains construct our perception ofcolor.
In other words, the key to producing the fireworks display you want isnt necessarily to create light of a specific color that corresponds to a specific wavelength, but rather to create light that excites the right molecules in our body to cause our brain to perceive a particular color.
A violet laser emits photons of a very particular, narrow wavelength, as every photon carries the same amount of energy. This curve, shown in blue, emits violet photons only. The green curve shows how a computer screen approximates the same exact violet color by using a mix of different wavelengths of light. Both appear to be the same color to human eyes, but only one truly produces photons of the same color that our eyes perceive.
Fireworks might appear to be relatively simple explosive devices. Pack a charge into the bottom of a tube to lift the fireworks to the desired height, ignite a fuse of the proper length to reach the burst charge at the peak of its trajectory, explode the burst charge to distribute the stars at a high temperature, and then watch and listen to the show as the sound, light, and color washes over you.
Yet if we look a little deeper, we can understand how quantum physics underlies every single one of these reactions. Add a little bit extrasuch as propulsion or fuel inside each starand your colored lights can spin, rise, or thrust in a random direction. Make sure you enjoy your fourth of July safely, but also armed with the knowledge that empowers you to understand how the most spectacular human-made light show of the year truly works!
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A Particle is Born: Making the Higgs Famous – Physics
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June 30, 2022• Physics 15, 97
Science communicators had a field day with the 2012 Higgs discovery, as it offered a chance to energize the public about fundamental physics research.
This article is part of a series of pieces that Physics Magazine is publishing to celebrate the 10th anniversary of the Higgs boson discovery. See also (upcoming): Poem: Higgs Boson: The Visible Glyph; News Feature: The Era of Higgs Physics; Q&A: The Higgs Boson: A Theory, An Observation, A Tool; Podcast: The Higgs, Ten Years After; and Collection: The History of Observations of the Higgs Boson.
The Higgs discovery, announced on July 4, 2012, was a major happening in science but also in science communication. Rarely has so much effort been made to engage the public over a fundamental physics topic. Front-page headlines, best-selling books, public lectures, TV interviews, and feature-length films all tried to explain the Higgs bosona particle whose claim to fame is its association with the generation of mass. Ten years later, the Higgs may not be a household name, but the intense limelight on this fundamental entity did offer communicators an opportunity to tell a larger story about the scientific enterprise.
The Higgs boson is the capstone of the standard model of particle physics, says physicist Sean Carroll from the California Institute of Technology, who wrote about the Higgs in his 2012 book The Particle at the End of the Universe. Hes also helped to popularize the Higgs by giving public lectures, writing blogs, and making TV appearances. He believes the discovery was a watershed moment, as it showed that physicists were clearly on the right track with their understanding of the fundamental workings of the Universe. That kind of accomplishment should not go unrecognized, Carroll says.
So how have science communicators tried to make the Higgs boson famous? One of the earliest attempts was by the Nobel prize winner Leon Lederman, who wrote the 1993 popular science book The God Particle. In it, Lederman described the Higgs as the crucial but elusive piece to our understanding of the structure of matter. [The book] was spectacularly successful in that you literally cannot have a conversation with a person on the street about the Higgs without someone talking about the God particle, Carroll says. But many physicists regret the connection that was made between the Higgs and religion. Theres a lot of work to be done in undoing the damage, Carroll says.
Another early attempt at capturing the publics imagination came with the cocktail party analogy, which earned David Miller of the University College London a bottle of champagne from the UK science minister in 1993. Miller likened the Higgs fielda space-filling energy out of which the Higgs boson arisesto a bustling crowd of partygoers. When a celebrity tries to walk through the room, the crowd presses toward them, slowing their progress. In a similar way, the Higgs field can be drawn toward a particle, slowing its progress and giving it mass. The Higgs is more drawn, for example, to the top quark than to the up quark, hence the top is more massive than the up.
These types of metaphors offer a basic appreciation of the physics behind the Higgs boson and its field. But getting people to take the time to learn about the Higgs requires a more human approach, says Mark Levinsondirector of the 2013 film Particle Fever. If you really want to get the message out, if you want to engage a bigger audience, it needs to be personalized, he says. His award-winning filmwhich ran in theaters across the globe and was distributed on Netflixrecounts the efforts at CERN in Geneva leading up to the Higgs discovery, with Levinsons cameras following a handful of theorists and experimentalists during their day-to-day activities. It is interesting to show why people pursue these incredibly abstract ideas, he says.
When Levinson started shooting in 2008, he was not focused on the Higgs boson, as physicists had warned him that a discovery might take too long to materialize. But once promising signs showed up at CERNs Large Hadron Collider (LHC), Levinson and his editor Walter Murch retooled their films narrative to give a leading role to the Higgs. They even created a graphic with the Higgs in the centera representation that the physics community has come to embrace, Levinson says (Fig. 1). The movies big climactic scene is when LHC scientists revealed their data to a packed auditorium that included a visibly moved Peter Higgs, who began working in the 1960salong with other theoristson his namesake particle. Seeing an 80-year-old physicist tear up over a vindication of his lifes work, thats a great story, Levinson says.
The 2012 announcement was a media hit as well, with over 12,000 news reports on the Higgs boson, according to James Gillies, who was head of CERNs communication group when the discovery was announced (Fig. 2). Like Levinson, Gillies believes the Higgs was an easy sell to the public because the human effort surrounding the discovery was so immense. We cast fundamental science as the latest step in humankinds journey of exploration, he says.
Gillies admits that it can be difficult to assess whether the Higgs excitement had a lasting impact on the publics appreciation of fundamental science. Very little data has been collected on changes in scientific understanding following a big discovery. But theres no doubt in my mind that CERN, LHC, and Higgs are quite common currency these days, Gillies says. My experience has taught me that people are more curious about basic research than we tend to think.
Levinson agrees. Many people have said, I really didnt understand it, but I loved the film. The science, he says, is rather complicated, but the story about scientists and their passion is something that audiences can identify with. The Higgs is fundamental to the physics theory, but its bigger than that, Levinson says. Its more about our quest to understand the way the Universe works.
Theres no shortage of enthusiasm among the public to learn about the Higgs boson, Carroll says. He thinks science communicators can always do better, but I think the Higgs boson is something where we did take advantage of the excitement to teach people a little bit of physics. For his part, Carroll used the discovery to explain some of the quantum field theory that lies at the basis of the Higgs boson prediction. We might as well leverage our big, happy discoveries to better acquaint the public with how science works and what scientists are finding.
Michael Schirber
Michael Schirber is a Corresponding Editor forPhysics Magazine based in Lyon, France.
Using radioactive tritium, scientists improve laboratory constraints on the overdensity signal of cosmic relic neutrinos by a factor of 100, an advance that should improve the chances of spotting this elusive particle. Read More
New neutrino-oscillation data show no sign of an anomalous signal seen in previous studies, but the analyses cant yet fully rule out its presence. Read More
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Kyle Kawagoe’s PhD Thesis Defense | Department of Physics | The University of Chicago – University of Chicago
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1:002:00 pm
*******************
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Kyle Kawagoe's PhDThesisDefense
Tuesday, July 5 2022 at 1:00 PM CDT
MICROSCOPIC DEFINITIONS OF TOPOLOGICAL DATA
Condensed matter physics rests its foundation on the notion of phases of matter with universal properties. As it is not possible to understand the detailed motions of large collections of particles by tracking them individually, we must rely on the fact that, much of the time, these details are irrelevant to a comprehensive understanding of a macroscopic system. Rather, we must understand the collective behavior of materials via a small set of quantities which summarize this information. For topological phases of matter, which are realized in quantum many-body systems, we can understand their most basic properties from information called ``topological data." This topological data describes the phase of matter of these systems and carries with it a broad array of information about their behavior. Previously, the nature of this data was broadly understood, but in most cases was lacking a concrete interpretation in terms of the microscopic details of these systems.
In this talk, I will resolve this issue by giving concrete definitions of the topological data in terms of a small number of microscopic properties of these systems. These definitions serve not only as a tool to analyze these theories, but also bridge a conceptual gap between the abstract mathematical understanding of these phases of matter with the concrete physical models that physicists study. I will discuss two types of (2+1)D topological phases of matter: intrinsic topological phases (exemplified by fractional quantum Hall states) and symmetry protected topological phases (exemplified by topological insulators). For intrinsic topological order, I will describe data which can be derived from properties of their anyons.For symmetry protected topological phases, I will show how to extract the data from the properties of their edge modes.
Committee Members:
(Chair): Michael Levin
Dam T. Son
Arvind Murugan
Jonathan Simon
Kyle will be heading to The Ohio State University as a Postdoctoral Scholar in the Physics Department, advised by Brian Skinner and Yuan-Ming Lu, and as a PhD Lecturer in the Mathematics Department, teaching and doing research with David Penneys. In these dual roles, he will continue bridging the gap between the physical and mathematical perspectives of condensed matter physics and will remain dedicated to his passion for pedagogy.
Thesis Defense
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AdS/CFT: 25 Years of the ‘Bridge’ to an Unknowable Universe – The Wire Science
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An artists impression of a black hole and its accretion disk. Illustration: XMM-Newton, ESA, NASA
Twenty-five years ago, in 1997, an Argentine physicist named Juan Martin Maldacena published what would become the most highly cited physics paper in history (more than 20,000 to date). In the paper, Maldacena described a bridge between two theories that describe how our world works, but separately, without meeting each other. These are the field theories that describe the behaviour of energy fields (like the electromagnetic fields) and subatomic particles, and the theory of general relativity, which deals with gravity and the universe at the largest scales.
Field theories have many types and properties. One of them is a conformal field theory: a field theory that doesnt change when it undergoes a conformal transformation i.e. one which preserves angles but not lengths pertaining to the field. As such, conformal field theories are said to be mathematically well-behaved.
In relativity, space and time are unified into the spacetime continuum. This continuum can exist in many possible spaces. Some of these spaces have the same curvature everywhere, and come in three forms (roughly, universes of certain shapes): de Sitter space, Minkowski space and anti-de Sitter space. de Sitter space has positive curvature everywhere like a sphere (but is empty of any matter). Minkowski space has zero curvature everywhere i.e. a flat surface. Anti-de Sitter space has negative curvature everywhere like a hyperbola.
Because these shapes are related to the way our universe looks and works, cosmologists have their own way to understand them. If the spacetime continuum exists in de Sitter space, the universe is said to have a positive cosmological constant. Similarly, Minkowski space implies a zero cosmological constant and anti-de Sitter space a negative cosmological constant. Studies by various space telescopes have found that our universe has a positive cosmological constant, meaning it is approximately a de Sitter space (but not exactly since our universe does have matter).
In 1997, Maldacena found evidence to suggest that a description of quantum gravity in anti-de Sitter space in N dimensions is the same as a conformal field theory in N 1 dimensions. This AdS/CFT correspondence was an unexpected but monumental discovery that connected two kinds of theories that had thus far refused to cooperate.
The Wire Science had a chance to interview Maldacena about his past and current work in 2018, in which he provided more insights on AdS/CFT as well.
In his paper, Maldacena showed that in a very specific case, quantum gravity in anti-de Sitter space in five dimensions was the same as a specific conformal field theory in four dimensions. He conjectured that this equivalence would hold not just for the limiting case but the full theories. So the correspondence is also called the AdS/CFT conjecture. Physicists have not proven this to be the case so far but there is circumstantial evidence from many results that indicate that the conjecture is true.
Nonetheless, the finding was hailed as a major mathematical victory for string theory as well. This theory is a leading contender for one that can unify quantum mechanics and general relativity. However, we have found no experimental evidence of string theorys many claims.
Nonetheless, thanks to the correspondence, (mathematical) physicists have found that some problems that are hard on the AdS side are much easier to crack on the CFT side, and vice versa all they had to do was cross Maldacenas bridge! This was another sign that the AdS/CFT correspondence wasnt just a mathematical trick but could be a legitimate description of reality.
So how could it be real?
The holographic principle
In 1997, Maldacena proved that a string theory in five dimensions was the same as a conformal field theory in four dimensions. However, gravity in our universe exists in four dimensions not five. So the correspondence came close to providing a unified description of gravity and quantum mechanics, but not close enough. Nonetheless, it gave rise to the possibility that an entity that exists in some number of dimensions could be described by another entity that exists in one fewer number of dimensions.
Actually, in fact, the AdS/CFT correspondence didnt give rise to this possibility but realised it mathematically. The awareness of the possibility had existed for many years until then, as the holographic principle. The Dutch physicist Gerardus t Hooft first proposed it and the American physicist Leonard Susskind in the 1990s brought it firmly into the realm of string theory. One way to state the holographic principle, in the words of physicist Matthew Headrick, is thus:
The universe around us, which we are used to thinking of as being three dimensional, is actually at a more fundamental level two-dimensional and that everything we see thats going on around us in three dimensions is actually happening in a two-dimensional space.
This two-dimensional space is the surface of the universe, located at an infinite distance from us, where information is encoded that describes everything happening within the universe. Its a mind-boggling idea. Information here refers to physical information, such as, to use one of Headricks examples, the positions and velocities of physical objects. In beholding this information from the infinitely faraway surface, we apparently behold a three-dimensional reality.
It bears repeating that this is a mind-boggling idea. We have no proof so far that the holographic principle is a real description of our universe we only know that it could describe our reality, thanks to the AdS/CFT correspondence. This said, physicists have used the holographic principle to study and understand black holes.
In 1915, Albert Einsteins general theory of relativity provided a set of complicated equations to understand how mass, the spacetime continuum and the gravitational force are related. Within a few months, physicists Karl Swarzschild and Johannes Droste, followed in subsequent years by Georges Lematre, Subrahmanyan Chandrasekhar, Robert Oppenheimer and David Finkelstein, among others, began to realise that one of the equations exact solutions (i.e. non-approximate) indicated the existence of a point mass around which space was wrapped completely, preventing even light from escaping from inside this space to outside. This was the black hole.
Because black holes were exact solutions, physicists assumed that they didnt have any entropy i.e. that its insides didnt have any disorder. If there had been such disorder, it would have appeared in Einsteins equations. It didnt, so QED. But in the early 1970s, the Israeli-American physicist Jacob Bekenstein noticed a problem: if a system with entropy, like a container of hot gas, was thrown into the black hole, and the black hole doesnt have entropy, where does the entropy go? It had to go somewhere; otherwise, the black hole would violate the second law of thermodynamics that the entropy of an isolated system, like our universe, cant decrease.
Bekenstein postulated that black holes must also have entropy, and that the amount of entropy is proportional to the black holes surface area, i.e. the area of the event horizon. Bekenstein also worked out that there is a limit to the amount of entropy a given volume of space can contain, as well as that all black holes could be described by just three observable attributes: their mass, electric charge and angular momentum. So if a black holes entropy increases because it has swallowed some hot gas, this change ought to manifest as a change in one, some or all of these three attributes.
Taken together: when some hot gas is tossed into a black hole, the gas would fall into the event horizon but the information about its entropy might appear to be encoded on the black holes surface, from the point of view of an observer located outside and away from the event horizon. Note here that the black hole, a sphere, is a three-dimensional object whereas its surface is a flat, curved sheet and therefore two-dimensional. That is, all the information required to describe a 3D black hole could in fact be encoded on its 2D surface.
Doesnt this remind you of the AdS/CFT correspondence? For example, consider a five-dimensional anti-de Sitter space inside which there is a black hole. We can use the correspondence to show that the entropy of the theory that describes the boundary of this space matches exactly with the entropy of the black hole itself. This would realise the conjecture of t Hooft and others except here, the information is encoded not on the event horizon but on the boundary of the five-dimensional space itself.
This is just one example of the wider context that the AdS/CFT correspondence inhabits. For more examples and other insights, do read Maldacenas interview with The Wire Science.
The author is grateful to Nirmalya Kajuri for discussion and feedback on this article.
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Information Can Escape a Black Hole Both On the Outside and Possibly to Another Universe (Stephen Hawkings – The Daily Galaxy –Great Discoveries…
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Posted on Jun 26, 2022 in Black Holes, Physics, Science
It has been said that Newton gave us answers; Stephen Hawking gave us questions. A trio of physicists appear one step closer to resolving the black-hole information paradox, one of the most intriguing physics mysteries of our time.
Spacetime seems to fall apart at a black hole, implying that space-time is not the root level of reality as suggested by the famous paradox that Stephen Hawking first described five decades ago, but emerges from something deeper, observes George Musser, author of Spooky Action at a Distance, for Quanta about Hawkings seminal theory that in a fiery marriage of relativity and quantum physics says that when a black hole forms and then subsequently evaporates away completely by emitting radiation, the information that went into the black hole cannot come back out and is inevitably lost, violating the laws of physics that insist unequivocally that information can never get totally lost.
Enter EinsteinThe Dissolution of Spacetime
In 2003, Hawking found a way that information might escape during the holes evaporation, but he did not prove that the information escapes, so the paradox continued, until now. They are not the eternal prisons they were once thought of, Hawking said. Things can get out of a black hole both on the outside and possibly to another universe.
Although Einstein conceived of gravity as the curved geometry of space-time, his theory also entails the dissolution of space-time, which is ultimately why information can escape its gravitational prison, adds Musser, summarizing a landmark series of calculations by three physicists that show that information does escape a black hole through the workings of ordinary gravity with a single layer of quantum effects, which seems impossible by definition based on new gravitational calculations that Einsteins theory permits, but that Hawking did not include.
The Most Exciting Thing Since Hawking
That is the most exciting thing that has happened in this subject, I think, since Hawking, said one of the co-authors, Donald Marolf of the University of California, Santa Barbara.
Its from that mysterious area where relativity and quantum mechanics dont quite mesh, that the question of what happens to information in a black hole emerges, says says researcher Henry Maxfield at the University of California, Santa Barbara in calculating the quantum information content of a black hole and its radiation.
The Big Question
Maxfield was co-author of a paper, co-written with physicists Ahmed Almheiri at the Institute for Advanced Study and MITs Netta Engelhardt and Marolf UC Santa Barbara in 2019, that takes us one step closer, says Maxfield, to resolving the black hole information paradox. The hope was, if we could answer this question if we could see the information coming out in order to do that we would have had to learn about the microscopic theory, said Geoff Penington of the University of California, Berkeley, alluding to a fully quantum theory of gravity.
Black Holes Gently Glow and Radiate
It goes back to this problem in the 1970s that Stephen Hawking discovered, Maxfield explained. Black holes those extremely dense, high-gravity voids in space-time arent completely black. They gently glow and radiate, he said. And as they do that, the black holes evaporate. But one element of Hawkings calculations, Maxfield continued, is that this state of Hawking radiation destroys information about the original quantum state of the material drawn into the hole.
This is very different from what quantum mechanics does, Maxfield said. In principle, the laws of physics are completely reversible. In other words, information about the materials original quantum state should exist in some form. So there was this conflict that quantum mechanics behaves one way and gravity seems to behave another way.
Tip of the Iceberg
We were interested in something closely related, which was trying to identify where the information is located, Maxfield said about the non-linear path to their calculation as a modification to Hawkings calculation broadening it to include a method for quantifying the information.
So theres that early radiation when the black hole is still young that doesnt really carry any information, Maxfield said about their calculation about how much information is stored in a black hole as it evaporates, and the finding that the amount of information indeed decreases over time.. But once the black hole has shrunk away to half its size it takes a very long time the quantum information starts coming out. This is what youd expect from quantum mechanics.
The calculation that Maxfield, Englehardt, Almheiri and Geoff Penington (who was concurrently doing very similar work at Stanford) made, reports UC Santa Barbara, is but a tip of the iceberg.
The Biggest Clue Weve Had
It doesnt mean that weve completely understood everything, Maxfield said. But it is the biggest clue weve had for a really long time as to how this tension gets resolved.
They found that the information is coming out, even if they didnt have all the reasons why it comes out, Marolf commented. But the idea is that this is a first step. If you have a way of performing that calculation, you should be able to open that calculation up and figure out what the physical mechanism is. This calculation is something we expect is going to give us insight into quantum processes in black holes and how information comes out of them.
Im very resistant to people who come in and say, Ive got a solution in just quantum mechanics and gravity, said a skeptical Nick Warner of the University of Southern California. Because its taken us around in circles before.
Max Goldberg via UC Santa Barbara and Quanta
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