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Javier E

Physicists in Europe Find Tantalizing Hints of a Mysterious New Particle - The New York... - 0 views

  • Two teams of physicists working independently at the Large Hadron Collider at CERN, the European Organization for Nuclear Research, reported on Tuesday that they had seen traces of what could be a new fundamental particle of nature.
  • One possibility, out of a gaggle of wild and not-so-wild ideas springing to life as the day went on, is that the particle — assuming it is real — is a heavier version of the Higgs boson, a particle that explains why other particles have mass. Another is that it is a graviton, the supposed quantum carrier of gravity, whose discovery could imply the existence of extra dimensions of space-time.
  • At the end of a long chain of “ifs” could be a revolution, the first clues to a theory of nature that goes beyond the so-called Standard Model, which has ruled physics for the last quarter-century.
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  • The Higgs boson was the last missing piece of the Standard Model, which explains all we know about subatomic particles and forces. But there are questions this model does not answer, such as what happens at the bottom of a black hole, the identity of the dark matter and dark energy that rule the cosmos, or why the universe is matter and not antimatter.
  • When physicists announced in 2012 that they had indeed discovered the Higgs boson, it was not the end of physics. It was not even, to paraphrase Winston Churchill, the beginning of the end.
  • A coincidence is the most probable explanation for the surprising bumps in data from the collider, physicists from the experiments cautioned, saying that a lot more data was needed and would in fact soon be available
  • The Large Hadron Collider was built at a cost of some $10 billion, to speed protons around an 18-mile underground track at more than 99 percent of the speed of light and smash them together in search of new particles and forces of nature. By virtue of Einstein’s equivalence of mass and energy, the more energy poured into these collisions, the more massive particles can come out of them. And by the logic of quantum microscopy, the more energy they have to spend, the smaller and more intimate details of nature physicists can see.
  • Since June, after a two-year shutdown, CERN physicists have been running their collider at nearly twice the energy with which they discovered the Higgs, firing twin beams of protons with 6.5 trillion electron volts of energy at each other in search of new particles to help point them to deeper laws.
  • The most intriguing result so far, reported on Tuesday, is an excess of pairs of gamma rays corresponding to an energy of about 750 billion electron volts. The gamma rays, the physicists said, could be produced by the radioactive decay of a new particle, in this case perhaps a cousin of the Higgs boson, which itself was first noticed because it decayed into an abundance of gamma rays.
  • Or it could be a more massive particle that has decayed in steps down to a pair of photons. Nobody knows. No model predicted this, which is how some scientists like it.
  • “We are barely coming to terms with the power and the glory” of the CERN collider’s ability to operate at 13 trillion electron volts, Dr. Spiropulu said in a text message. “We are now entering the era of taking a shot in the dark!”
kushnerha

Physicists in Europe Find Tantalizing Hints of a Mysterious New Particle - The New York... - 1 views

  • seen traces of what could be a new fundamental particle of nature.
  • One possibility, out of a gaggle of wild and not-so-wild ideas springing to life as the day went on, is that the particle — assuming it is real — is a heavier version of the Higgs boson, a particle that explains why other particles have mass. Another is that it is a graviton, the supposed quantum carrier of gravity, whose discovery could imply the existence of extra dimensions of space-time.
  • At the end of a long chain of “ifs” could be a revolution, the first clues to a theory of nature that goes beyond the so-called Standard Model, which has ruled physics for the last quarter-century.
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  • noting that the history of particle physics is rife with statistical flukes and anomalies that disappeared when more data was compiled
  • A coincidence is the most probable explanation for the surprising bumps in data from the collider, physicists from the experiments cautioned
  • Physicists could not help wondering if history was about to repeat itself. It was four years ago this week that the same two teams’ detection of matching bumps in Large Hadron Collider data set the clock ticking for the discovery of the Higgs boson six months later.
  • If the particle is real, Dr. Lykken said, physicists should know by this summer, when they will have 10 times as much data to present to scientists from around the world who will convene in Chicago
  • The Higgs boson was the last missing piece of the Standard Model, which explains all we know about subatomic particles and forces. But there are questions this model does not answer, such as what happens at the bottom of a black hole, the identity of the dark matter and dark energy that rule the cosmos, or why the universe is matter and not antimatter.
  • CERN physicists have been running their collider at nearly twice the energy with which they discovered the Higgs, firing twin beams of protons with 6.5 trillion electron volts of energy at each other in search of new particles to help point them to deeper laws.The main news since then has been mainly that there is no news yet, only tantalizing hints, bumps in the data, that might be new particles and signposts of new theories, or statistical demons.
  • Or it could be a more massive particle that has decayed in steps down to a pair of photons. Nobody knows. No model predicted this, which is how some scientists like it.
  • “The more nonstandard the better,” said Joe Lykken, the director of research at the Fermi National Accelerator Laboratory and a member of one of the CERN teams. “It will give people a lot to think about. We get paid to speculate.”
  • When physicists announced in 2012 that they had indeed discovered the Higgs boson, it was not the end of physics. It was not even, to paraphrase Winston Churchill, the beginning of the end.It might, they hoped, be the end of the beginning.
  • Such a discovery would augur a fruitful future for cosmological wanderings and for the CERN collider, which will be running for the next 20 years.
Javier E

Seeking Dark Matter, They Detected Another Mystery - The New York Times - 0 views

  • A team of scientists hunting dark matter has recorded suspicious pings coming from a vat of liquid xenon underneath a mountain in Italy
  • If the signal is real and persists, the scientists say, it may be evidence of a species of subatomic particles called axions — long theorized to play a crucial role in keeping nature symmetrical but never seen — streaming from the sun.
  • Instead of axions, the scientists may have detected a new, unexpected property of the slippery ghostly particles called neutrinos. Yet another equally likely explanation is that their detector has been contaminated by vanishingly tiny amounts of tritium, a rare radioactive form of hydrogen.
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  • “We want to be very clear that all we are reporting is observation of an excess (a fairly significant one) and not a discovery of any kind,”
  • “I’m trying to be calm here, but it’s hard not to be hyperbolic,” said Neal Weiner, a particle theorist at New York University. “If this is real, calling it a game changer would be an understatement.”
  • Dr. Aprile’s Xenon experiment is currently the largest and most sensitive in an alphabet soup of efforts aimed at detecting and identifying dark matter
  • The best guess is that this dark matter consists of clouds of exotic subatomic particles left over from the Big Bang and known generically as WIMPs, for weakly interacting massive particles, hundreds or thousands of times more massive than a hydrogen atom.
  • The story of axions begins in 1977, when Roberto Peccei, a professor at the University of California, Los Angeles, who died on June 1, and Helen Quinn, emerita professor at Stanford, suggested a slight modification to the theory that governs strong nuclear forces, making sure that it is invariant to the direction of time, a feature that physicists consider a necessity for the universe.
  • in its most recent analysis of that experiment, the team had looked for electrons, rather than the heavier xenon nuclei, recoiling from collisions. Among other things, that could be the signature of particles much lighter than the putative WIMPs striking the xenon.
  • Simulations and calculations suggested that random events should have produced about 232 such recoils over the course of a year.
  • But from February 2017 to February 2018, the detector recorded 285, an excess of 53 recoils.
  • Dr. Aprile and her colleagues have wired a succession of vats containing liquid xenon with photomultipliers and other sensors. The hope is that her team’s device — far underground to shield it from cosmic rays and other worldly forms of interference — would spot the rare collision between a WIMP and a xenon atom. The collision should result in a flash of light and a cloud of electrical charge.
  • this modification implied the existence of a new subatomic particle. Dr. Wilczek called it the axion, and the name stuck.
  • Axions have never been detected either directly or indirectly. And the theory does not predict their mass, which makes it hard to look for them. It only predicts that they would be weird and would barely interact with regular matter
  • although they are not WIMPS, they share some of those particles’ imagined weird abilities, such as being able to float through Earth and our bodies like smoke through a screen door.
  • In order to fulfill the requirements of cosmologists, however, such dark-matter axions would need to have a mass of less than a thousandth of an electron volt in the units of mass and energy preferred by physicists
  • (By comparison, the electrons that dance around in your smartphone weigh in at half a million electron volts each.) What they lack in heft they would more than make up for in numbers.
  • That would make individual cosmic dark-matter axions too slow and ethereal to be detected by the Xenon experiment.But axions could also be produced by nuclear reactions in the sun, and those “solar axions” would have enough energy to ping the Xenon detector right where it is most sensitive
  • The other exciting, though slightly less likely, possibility is that the Xenon collaboration’s excess signals come from the wispy particles known as neutrinos, which are real, and weird, and zipping through our bodies by the trillions every second.
  • Ordinarily, these neutrinos would not contribute much to the excess of events the detector read. But they would do so if they had an intrinsic magnetism that physicists call a magnetic moment. That would give them a higher probability of interacting with the xenon and tripping the detector
  • According to the standard lore, neutrinos, which are electrically neutral, do not carry magnetism. The discovery that they did would require rewriting the rules as they apply to neutrinos.
  • That, said Dr. Weiner, would be “a very very big deal,” because it would imply that there are new fundamental particles out there to look for — new physics.
Javier E

Peter Higgs, physicist who discovered Higgs boson, dies aged 94 | Peter Higgs | The Gua... - 0 views

  • Peter Higgs, the Nobel prize-winning physicist who discovered a new particle known as the Higgs boson, has died.Higgs, 94, who was awarded the Nobel prize for physics in 2013 for his work in 1964 showing how the boson helped bind the universe together by giving particles their mass
  • “A giant of particle physics has left us,” Ellis told the Guardian. “Without his theory, atoms could not exist and radioactivity would be a force as strong as electricity and magnetism.
  • “His prediction of the existence of the particle that bears his name was a deep insight, and its discovery at Cern in 2012 was a crowning moment that confirmed his understanding of the way the Universe works.”
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  • The particle that carries his name is perhaps the single most stunning example of how seemingly abstract mathematical ideas can make predictions which turn out to have huge physical consequences.”
  • The Royal Swedish Academy of Sciences, which awards the Nobel, said at the time the standard model of physics which underpins the scientific understanding of the universe “rests on the existence of a special kind of particle: the Higgs particle. This particle originates from an invisible field that fills up all space.“Even when the universe seems empty this field is there. Without it, we would not exist, because it is from contact with the field that particles acquire mass. The theory proposed by Englert and Higgs describes this process.”
Javier E

Opinion | Why Covid's Airborne Transmission Was Acknowledged So Late - The New York Times - 0 views

  • A week ago, more than a year after the World Health Organization declared that we face a pandemic, a page on its website titled “Coronavirus Disease (Covid-19): How Is It Transmitted?” got a seemingly small update.
  • The revised response still emphasizes transmission in close contact but now says it may be via aerosols — smaller respiratory particles that can float — as well as droplets. It also adds a reason the virus can also be transmitted “in poorly ventilated and/or crowded indoor settings,” saying this is because “aerosols remain suspended in the air or travel farther than 1 meter.”
  • on Friday, the Centers for Disease Control and Prevention also updated its guidance on Covid-19, clearly saying that inhalation of these smaller particles is a key way the virus is transmitted, even at close range, and put it on top of its list of how the disease spreads.
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  • But these latest shifts challenge key infection control assumptions that go back a century, putting a lot of what went wrong last year in context
  • They may also signal one of the most important advancements in public health during this pandemic.
  • If the importance of aerosol transmission had been accepted early, we would have been told from the beginning that it was much safer outdoors, where these small particles disperse more easily, as long as you avoid close, prolonged contact with others.
  • We would have tried to make sure indoor spaces were well ventilated, with air filtered as necessary.
  • Instead of blanket rules on gatherings, we would have targeted conditions that can produce superspreading events: people in poorly ventilated indoor spaces, especially if engaged over time in activities that increase aerosol production, like shouting and singing
  • We would have started using masks more quickly, and we would have paid more attention to their fit, too. And we would have been less obsessed with cleaning surfaces.
  • The implications of this were illustrated when I visited New York City in late April — my first trip there in more than a year.
  • A giant digital billboard greeted me at Times Square, with the message “Protecting yourself and others from Covid-19. Guidance from the World Health Organization.”
  • That billboard neglected the clearest epidemiological pattern of this pandemic: The vast majority of transmission has been indoors, sometimes beyond a range of three or even six feet. The superspreading events that play a major role in driving the pandemic occur overwhelmingly, if not exclusively, indoors.
  • The billboard had not a word about ventilation, nothing about opening windows or moving activities outdoors, where transmission has been rare and usually only during prolonged and close contact. (Ireland recently reported 0.1 percent of Covid-19 cases were traced to outdoor transmission.)
  • Mary-Louise McLaws, an epidemiologist at the University of New South Wales in Sydney, Australia, and a member of the W.H.O. committees that craft infection prevention and control guidance, wanted all this examined but knew the stakes made it harder to overcome the resistance. She told The Times last year, “If we started revisiting airflow, we would have to be prepared to change a lot of what we do.” She said it was a very good idea, but she added, “It will cause an enormous shudder through the infection control society.”
  • In contrast, if the aerosols had been considered a major form of transmission, in addition to distancing and masks, advice would have centered on ventilation and airflow, as well as time spent indoors. Small particles can accumulate in enclosed spaces, since they can remain suspended in the air and travel along air currents. This means that indoors, three or even six feet, while helpful, is not completely protective, especially over time.
  • To see this misunderstanding in action, look at what’s still happening throughout the world. In India, where hospitals have run out of supplemental oxygen and people are dying in the streets, money is being spent on fleets of drones to spray anti-coronavirus disinfectant in outdoor spaces. Parks, beaches and outdoor areas keep getting closed around the world. This year and last, organizers canceled outdoor events for the National Cherry Blossom Festival in Washington, D.C. Cambodian customs officials advised spraying disinfectant outside vehicles imported from India. The examples are many.
  • Meanwhile, many countries allowed their indoor workplaces to open but with inadequate aerosol protections. There was no attention to ventilation, installing air filters as necessary or even opening windows when possible, more to having people just distancing three or six feet, sometimes not requiring masks beyond that distance, or spending money on hard plastic barriers, which may be useless at best
  • clear evidence doesn’t easily overturn tradition or overcome entrenched feelings and egos. John Snow, often credited as the first scientific epidemiologist, showed that a contaminated well was responsible for a 1854 London cholera epidemic by removing the suspected pump’s handle and documenting how the cases plummeted afterward. Many other scientists and officials wouldn’t believe him for 12 years, when the link to a water source showed up again and became harder to deny.
  • Along the way to modern public health shaped largely by the fight over germs, a theory of transmission promoted by the influential public health figure Charles Chapin took hold
  • Dr. Chapin asserted in the early 1900s that respiratory diseases were most likely spread at close range by people touching bodily fluids or ejecting respiratory droplets, and did not allow for the possibility that such close-range infection could occur by inhaling small floating particles others emitted
  • He was also concerned that belief in airborne transmission, which he associated with miasma theories, would make people feel helpless and drop their guard against contact transmission. This was a mistake that would haunt infection control for the next century and more.
  • It was in this context in early 2020 that the W.H.O. and the C.D.C. asserted that SARS-CoV-2 was transmitted primarily via these heavier, short-range droplets, and provided guidance accordingly
  • Amid the growing evidence, in July, hundreds of scientists signed an open letter urging the public health agencies, especially the W.H.O., to address airborne transmission of the coronavirus.
  • Last October, the C.D.C. published updated guidance acknowledging airborne transmission, but as a secondary route under some circumstances, until it acknowledged airborne transmission as crucial on Friday. And the W.H.O. kept inching forward in its public statements, most recently a week ago.
  • Linsey Marr, a professor of engineering at Virginia Tech who made important contributions to our understanding of airborne virus transmission before the pandemic, pointed to two key scientific errors — rooted in a lot of history — that explain the resistance, and also opened a fascinating sociological window into how science can get it wrong and why.
  • Dr. Marr said that if you inhale a particle from the air, it’s an aerosol.
  • biomechanically, she said, nasal transmission faces obstacles, since nostrils point downward and the physics of particles that large makes it difficult for them to move up the nose. And in lab measurements, people emit far more of the easier-to-inhale aerosols than the droplets, she said, and even the smallest particles can be virus laden, sometimes more so than the larger ones, seemingly because of how and where they are produced in the respiratory tract.
  • Second, she said, proximity is conducive to transmission of aerosols as well because aerosols are more concentrated near the person emitting them. In a twist of history, modern scientists have been acting like those who equated stinky air with disease, by equating close contact, a measure of distance, only with the larger droplets, a mechanism of transmission, without examination.
  • Since aerosols also infect at close range, measures to prevent droplet transmission — masks and distancing — can help dampen transmission for airborne diseases as well. However, this oversight led medical people to circularly assume that if such measures worked at all, droplets must have played a big role in their transmission.
  • Another dynamic we’ve seen is something that is not unheard-of in the history of science: setting a higher standard of proof for theories that challenge conventional wisdom than for those that support it.
  • Another key problem is that, understandably, we find it harder to walk things back. It is easier to keep adding exceptions and justifications to a belief than to admit that a challenger has a better explanation.
  • The ancients believed that all celestial objects revolved around the earth in circular orbits. When it became clear that the observed behavior of the celestial objects did not fit this assumption, those astronomers produced ever-more-complex charts by adding epicycles — intersecting arcs and circles — to fit the heavens to their beliefs.
  • In a contemporary example of this attitude, the initial public health report on the Mount Vernon choir case said that it may have been caused by people “sitting close to one another, sharing snacks and stacking chairs at the end of the practice,” even though almost 90 percent of the people there developed symptoms of Covid-19
  • So much of what we have done throughout the pandemic — the excessive hygiene theater and the failure to integrate ventilation and filters into our basic advice — has greatly hampered our response.
  • Some of it, like the way we underused or even shut down outdoor space, isn’t that different from the 19th-century Londoners who flushed the source of their foul air into the Thames and made the cholera epidemic worse.
  • Righting this ship cannot be a quiet process — updating a web page here, saying the right thing there. The proclamations that we now know are wrong were so persistent and so loud for so long.
  • the progress we’ve made might lead to an overhaul in our understanding of many other transmissible respiratory diseases that take a terrible toll around the world each year and could easily cause other pandemics.
  • So big proclamations require probably even bigger proclamations to correct, or the information void, unnecessary fears and misinformation will persist, damaging the W.H.O. now and in the future.
  • I’ve seen our paper used in India to try to reason through aerosol transmission and the necessary mitigations. I’ve heard of people in India closing their windows after hearing that the virus is airborne, likely because they were not being told how to respond
  • The W.H.O. needs to address these fears and concerns, treating it as a matter of profound change, so other public health agencies and governments, as well as ordinary people, can better adjust.
  • It needs to begin a campaign proportional to the importance of all this, announcing, “We’ve learned more, and here’s what’s changed, and here’s how we can make sure everyone understands how important this is.” That’s what credible leadership looks like. Otherwise, if a web page is updated in the forest without the requisite fanfare, how will it matter?
carolinewren

The Reality of Quantum Weirdness - NYTimes.com - 2 views

  • Is there a true story, or is our belief in a definite, objective, observer-independent reality an illusion?
  • Is there a fixed reality apart from our various observations of it? Or is reality nothing more than a kaleidoscope of infinite possibilities?
  • So an electron is a wave, not a particle?
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  • each electron somehow acts like a wave interfering with itself, as if it is simultaneously passing through both slits at once.
  • the electrons go back to their wavelike behavior, and the interference pattern miraculously reappears.
  • Instead, we see two lumps on the screen, as if the electrons, suddenly aware of being observed, decided to act like little pellets.
  • . For an individual particle like an electron, for example, the wave function provides information about the probabilities that the particle can be observed at particular locations, as well as the probabilities of the results of other measurements of the particle that you can make, such as measuring its momentum.
  • If the wave function is merely knowledge-based, then you can explain away odd quantum phenomena by saying that things appear to us this way only because our knowledge of the real state of affairs is insufficient.
  • If there is an objective reality at all, the paper demonstrates, then the wave function is in fact reality-based.
  • We should be careful to recognize that the weirdness of the quantum world does not directly imply the same kind of weirdness in the world of everyday experience. That’s because the nebulous quantum essence of individual elementary particles is known to quickly dissipate in large ensembles of particles (a phenomenon often referred to as “decoherence”).
Javier E

What Does Quantum Physics Actually Tell Us About the World? - The New York Times - 2 views

  • The physics of atoms and their ever-smaller constituents and cousins is, as Adam Becker reminds us more than once in his new book, “What Is Real?,” “the most successful theory in all of science.” Its predictions are stunningly accurate, and its power to grasp the unseen ultramicroscopic world has brought us modern marvels.
  • But there is a problem: Quantum theory is, in a profound way, weird. It defies our common-sense intuition about what things are and what they can do.
  • The strange implication is that the reality of the quantum world remains amorphous or indefinite until scientists start measuring
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  • Before he died, Richard Feynman, who understood quantum theory as well as anyone, said, “I still get nervous with it...I cannot define the real problem, therefore I suspect there’s no real problem, but I’m not sure there’s no real problem.” The problem is not with using the theory — making calculations, applying it to engineering tasks — but in understanding what it means. What does it tell us about the world?
  • From one point of view, quantum physics is just a set of formalisms, a useful tool kit. Want to make better lasers or transistors or television sets? The Schrödinger equation is your friend. The trouble starts only when you step back and ask whether the entities implied by the equation can really exist. Then you encounter problems that can be described in several familiar ways:
  • Wave-particle duality. Everything there is — all matter and energy, all known forces — behaves sometimes like waves, smooth and continuous, and sometimes like particles, rat-a-tat-tat. Electricity flows through wires, like a fluid, or flies through a vacuum as a volley of individual electrons. Can it be both things at once?
  • The uncertainty principle. Werner Heisenberg famously discovered that when you measure the position (let’s say) of an electron as precisely as you can, you find yourself more and more in the dark about its momentum. And vice versa. You can pin down one or the other but not both.
  • The measurement problem. Most of quantum mechanics deals with probabilities rather than certainties. A particle has a probability of appearing in a certain place. An unstable atom has a probability of decaying at a certain instant. But when a physicist goes into the laboratory and performs an experiment, there is a definite outcome. The act of measurement — observation, by someone or something — becomes an inextricable part of the theory
  • Indeed, Heisenberg said that quantum particles “are not as real; they form a world of potentialities or possibilities rather than one of things or facts.”
  • Other interpretations rely on “hidden variables” to account for quantities presumed to exist behind the curtain.
  • This is disturbing to philosophers as well as physicists. It led Einstein to say in 1952, “The theory reminds me a little of the system of delusions of an exceedingly intelligent paranoiac.”
  • Competing approaches to quantum foundations are called “interpretations,” and nowadays there are many. The first and still possibly foremost of these is the so-called Copenhagen interpretation.
  • In a way, the Copenhagen is an anti-interpretation. “It is wrong to think that the task of physics is to find out how nature is,” Bohr said. “Physics concerns what we can say about nature.”
  • Nothing is definite in Bohr’s quantum world until someone observes it. Physics can help us order experience but should not be expected to provide a complete picture of reality. The popular four-word summary of the Copenhagen interpretation is: “Shut up and calculate!”
  • Becker sides with the worriers. He leads us through an impressive account of the rise of competing interpretations, grounding them in the human stories
  • He makes a convincing case that it’s wrong to imagine the Copenhagen interpretation as a single official or even coherent statement. It is, he suggests, a “strange assemblage of claims.
  • An American physicist, David Bohm, devised a radical alternative at midcentury, visualizing “pilot waves” that guide every particle, an attempt to eliminate the wave-particle duality.
  • “Figuring out what quantum physics is saying about the world has been hard,” Becker says, and this understatement motivates his book, a thorough, illuminating exploration of the most consequential controversy raging in modern science.
  • Perhaps the most popular lately — certainly the most talked about — is the “many-worlds interpretation”: Every quantum event is a fork in the road, and one way to escape the difficulties is to imagine, mathematically speaking, that each fork creates a new universe
  • if you think the many-worlds idea is easily dismissed, plenty of physicists will beg to differ. They will tell you that it could explain, for example, why quantum computers (which admittedly don’t yet quite exist) could be so powerful: They would delegate the work to their alter egos in other universes.
  • When scientists search for meaning in quantum physics, they may be straying into a no-man’s-land between philosophy and religion. But they can’t help themselves. They’re only human.
  • If you were to watch me by day, you would see me sitting at my desk solving Schrödinger’s equation...exactly like my colleagues,” says Sir Anthony Leggett, a Nobel Prize winner and pioneer in superfluidity. “But occasionally at night, when the full moon is bright, I do what in the physics community is the intellectual equivalent of turning into a werewolf: I question whether quantum mechanics is the complete and ultimate truth about the physical universe.”
sanderk

How Does Light Travel? - Universe Today - 0 views

  • However, there remains many fascinating and unanswered questions when it comes to light, many of which arise from its dual nature. For instance, how is it that light can be apparently without mass, but still behave as a particle? And how can it behave like a wave and pass through a vacuum, when all other waves require a medium to propagate?
  • This included rejecting Aristotle’s theory of light, which viewed it as being a disturbance in the air (one of his four “elements” that composed matter), and embracing the more mechanistic view that light was composed of indivisible atoms
  • In Young’s version of the experiment, he used a slip of paper with slits cut into it, and then pointed a light source at them to measure how light passed through it
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  • According to classical (i.e. Newtonian) particle theory, the results of the experiment should have corresponded to the slits, the impacts on the screen appearing in two vertical lines. Instead, the results showed that the coherent beams of light were interfering, creating a pattern of bright and dark bands on the screen. This contradicted classical particle theory, in which particles do not interfere with each other, but merely collide.
  • The only possible explanation for this pattern of interference was that the light beams were in fact behaving as waves
  • By the late 19th century, James Clerk Maxwell proposed that light was an electromagnetic wave, and devised several equations (known as Maxwell’s equations) to describe how electric and magnetic fields are generated and altered by each other and by charges and currents. By conducting measurements of different types of radiation (magnetic fields, ultraviolet and infrared radiation), he was able to calculate the speed of light in a vacuum (represented as c).
  • For one, it introduced the idea that major changes occur when things move close the speed of light, including the time-space frame of a moving body appearing to slow down and contract in the direction of motion when measured in the frame of the observer. After centuries of increasingly precise measurements, the speed of light was determined to be 299,792,458 m/s in 1975
  • According to his theory, wave function also evolves according to a differential equation (aka. the Schrödinger equation). For particles with mass, this equation has solutions; but for particles with no mass, no solution existed. Further experiments involving the Double-Slit Experiment confirmed the dual nature of photons. where measuring devices were incorporated to observe the photons as they passed through the slits.
  • For instance, its interaction with gravity (along with weak and strong nuclear forces) remains a mystery. Unlocking this, and thus discovering a Theory of Everything (ToE) is something astronomers and physicists look forward to. Someday, we just might have it all figured out!
Javier E

Nobel Prize in Physics Is Awarded to 3 Scientists for Work Exploring Quantum Weirdness ... - 0 views

  • “We’re used to thinking that information about an object — say that a glass is half full — is somehow contained within the object.” Instead, he says, entanglement means objects “only exist in relation to other objects, and moreover these relationships are encoded in a wave function that stands outside the tangible physical universe.”
  • Einstein, though one of the founders of quantum theory, rejected it, saying famously, God did not play dice with the universe.In a 1935 paper written with Boris Podolsky and Nathan Rosen, he tried to demolish quantum mechanics as an incomplete theory by pointing out that by quantum rules, measuring a particle in one place could instantly affect measurements of the other particle, even if it was millions of miles away.
  • Dr. Clauser, who has a knack for electronics and experimentation and misgivings about quantum theory, was the first to perform Bell’s proposed experiment. He happened upon Dr. Bell’s paper while a graduate student at Columbia University and recognized it as something he could do.
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  • In 1972, using duct tape and spare parts in the basement on the campus of the University of California, Berkeley, Dr. Clauser and a graduate student, Stuart Freedman, who died in 2012, endeavored to perform Bell’s experiment to measure quantum entanglement. In a series of experiments, he fired thousands of light particles, or photons, in opposite directions to measure a property known as polarization, which could have only two values — up or down. The result for each detector was always a series of seemingly random ups and downs. But when the two detectors’ results were compared, the ups and downs matched in ways that neither “classical physics” nor Einstein’s laws could explain. Something weird was afoot in the universe. Entanglement seemed to be real.
  • in 2002, Dr. Clauser admitted that he himself had expected quantum mechanics to be wrong and Einstein to be right. “Obviously, we got the ‘wrong’ result. I had no choice but to report what we saw, you know, ‘Here’s the result.’ But it contradicts what I believed in my gut has to be true.” He added, “I hoped we would overthrow quantum mechanics. Everyone else thought, ‘John, you’re totally nuts.’”
  • the correlations only showed up after the measurements of the individual particles, when the physicists compared their results after the fact. Entanglement seemed real, but it could not be used to communicate information faster than the speed of light.
  • In 1982, Dr. Aspect and his team at the University of Paris tried to outfox Dr. Clauser’s loophole by switching the direction along which the photons’ polarizations were measured every 10 nanoseconds, while the photons were already in the air and too fast for them to communicate with each other. He too, was expecting Einstein to be right.
  • Quantum predictions held true, but there were still more possible loopholes in the Bell experiment that Dr. Clauser had identified
  • For example, the polarization directions in Dr. Aspect’s experiment had been changed in a regular and thus theoretically predictable fashion that could be sensed by the photons or detectors.
  • Anton Zeilinger
  • added even more randomness to the Bell experiment, using random number generators to change the direction of the polarization measurements while the entangled particles were in flight.
  • Once again, quantum mechanics beat Einstein by an overwhelming margin, closing the “locality” loophole.
  • as scientists have done more experiments with entangled particles, entanglement is accepted as one of main features of quantum mechanics and is being put to work in cryptology, quantum computing and an upcoming “quantum internet
  • One of its first successes in cryptology is messages sent using entangled pairs, which can send cryptographic keys in a secure manner — any eavesdropping will destroy the entanglement, alerting the receiver that something is wrong.
  • , with quantum mechanics, just because we can use it, doesn’t mean our ape brains understand it. The pioneering quantum physicist Niels Bohr once said that anyone who didn’t think quantum mechanics was outrageous hadn’t understood what was being said.
  • In his interview with A.I.P., Dr. Clauser said, “I confess even to this day that I still don’t understand quantum mechanics, and I’m not even sure I really know how to use it all that well. And a lot of this has to do with the fact that I still don’t understand it.”
carolinewren

Researchers at Brown University shattered an electron wave function | Motherboard - 1 views

  • When we say some element of the quantum world occupies many states at once, what’s really being referred to is the element’s wave function. A wave function can be viewed as a space occupied simultaneously by many different possibilities or degrees of freedom.
  • Even what we’d normally (deterministically) consider empty space has a wave function and, as such, contains very real possibilities of not being empty.
  • Visually, we might imagine a particle in its undisturbed state looking more like a cloud than a point in space.
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  • a bunch of particles can share these states at the same time, effectively becoming instances of the same particle. And so: entanglement.
  • possible to strip away all of this indeterminateness
  • wave functions are very fragile, subject to a “collapse” in which all of those possibilities become just a single particle at a single point at a single time.
  • physicists have observed a very peculiar behavior of electrons in supercooled baths of helium. When an electron enters the bath, it acts to
  • two probabilities can be isolated from each other, cordoned off like quantum crime scenes
  • it’s possible to take a wave function and isolate it into different parts. So, if our electron has some probability of being in position (x1,y1,z1) and another probability of being in position (x2,y2,z2), those two probabilities can be isolated from each other, cordoned off like quantum crime scenes
  • when a macroscopic human attempts to measure a quantum mechanical system: The wave drops away and all that’s left is a boring, well-defined thing.
  • trapping the chance of finding the electron, not pieces of the electron
  • using tiny bubbles of helium as physical “traps.
  • repel the surrounding helium atoms, forming its own little bubble or cavity in the process.
  • That an electron (or other particle) can be in many places at the same time is strange enough, but the notion that those possibilities can be captured and shuttled away adds a whole new twist.
  • wave function isn’t a physical thing. It’s mathematics that describe a phenomenon.
  • The electron, upon measurement, will be in precisely one bubble.
  • “No one is sure what actually constitutes a measurement,”
  • Is consciousness required? We don’t really know.”
dpittenger

Departing Leader of CERN Ponders Uncertainties That Lie Ahead - 0 views

  • Dr. Heuer, born in Bad Boll in southern Germany in 1948, has spent his career in the trenches of particle physics, in which scientists emulate 3-year-olds by smashing bits of matter together to see what comes out.
  • He had an opportunity to put that philosophy to the test early in his term at CERN, when physicists reported in a seminar there that they had measured subatomic particles known as neutrinos streaming from Geneva to their detector in Italy faster than the speed of light, contrary to the laws of physics then known.
  • The neutrino controversy helped set a sort of dubious stage for the main event in particle physics so far this century: the Higgs boson.
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  • The Higgs boson completed the Standard Model, a suite of equations that agrees with all the experiments that have been done on earth. But that model is not the end of physics. It does not explain dark matter or dark energy, the two major constituents of the cosmos, for example, or why the universe is made of matter instead of antimatter.
  • For decades, theorists have flirted with a concept called supersymmetry that would address some of these issues and produce a bounty of new particles for CERN’s collider.
Javier E

Lockheed Martin Harnesses Quantum Technology - NYTimes.com - 0 views

  • academic researchers and scientists at companies like Microsoft, I.B.M. and Hewlett-Packard have been working to develop quantum computers.
  • Lockheed Martin — which bought an early version of such a computer from the Canadian company D-Wave Systems two years ago — is confident enough in the technology to upgrade it to commercial scale, becoming the first company to use quantum computing as part of its business.
  • if it performs as Lockheed and D-Wave expect, the design could be used to supercharge even the most powerful systems, solving some science and business problems millions of times faster
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  • It could be possible, for example, to tell instantly how the millions of lines of software running a network of satellites would react to a solar burst or a pulse from a nuclear explosion — something that can now take weeks, if ever, to determine.
  • “This is a revolution not unlike the early days of computing,” he said. “It is a transformation in the way computers are thought about.”
  • quantum computing relies on the fact that subatomic particles inhabit a range of states. Different relationships among the particles may coexist, as well. Those probable states can be narrowed to determine an optimal outcome among a near-infinitude of possibilities, which allows certain types of problems to be solved rapidly.
  • Mr. Brownell, who joined D-Wave in 2009, was until 2000 the chief technical officer at Goldman Sachs. “In those days, we had 50,000 servers just doing simulations” to figure out trading strategies, he said. “I’m sure there is a lot more than that now, but we’ll be able to do that with one machine, for far less money.”
  • If Microsoft’s work pans out, he said, the millions of possible combinations of the proteins in a human gene could be worked out “fairly easily.”
  • Quantum computing has been a goal of researchers for more than three decades, but it has proved remarkably difficult to achieve. The idea has been to exploit a property of matter in a quantum state known as superposition, which makes it possible for the basic elements of a quantum computer, known as qubits, to hold a vast array of values simultaneously.
  • There are a variety of ways scientists create the conditions needed to achieve superposition as well as a second quantum state known as entanglement, which are both necessary for quantum computing. Researchers have suspended ions in magnetic fields, trapped photons or manipulated phosphorus atoms in silicon.
  • In the D-Wave system, a quantum computing processor, made from a lattice of tiny superconducting wires, is chilled close to absolute zero. It is then programmed by loading a set of mathematical equations into the lattice. The processor then moves through a near-infinity of possibilities to determine the lowest energy required to form those relationships. That state, seen as the optimal outcome, is the answer.
johnsonle1

The Universe Is as Spooky as Einstein Thought - The Atlantic - 0 views

  •  
    According to standard quantum theory, particles have no definite states, only relative probabilities of being one thing or another-at least, until they are measured, when they seem to suddenly roll the dice and jump into formation.
Duncan H

Living in the Material World - NYTimes.com - 0 views

  • on a visit to the Academy of Sciences in Almaty some years ago I was presented with a souvenir meant to assure me that Central Asia was indeed still producing philosophy worthy of note. It was a collectively authored book entitled “The Development of Materialist Dialectics in Kazakhstan,” and I still display it proudly on my shelf. Its rough binding and paper bespeak economic hardship. It is packed with the traces of ideas, yet everything about the book announces its materiality.I had arrived in the Kazakh capital 1994, just in time to encounter the last of a dying breed: the philosopher as party functionary (they are all by now retired, dead or defenestrated, or have simply given up on what they learned in school). The book, written by committee, was a collection of official talking points, and what passed for conversation there was something much closer to recitation.
  • The philosophical meaning of materialism may in the final analysis be traced back to a religious view of the world. On this view, to focus on the material side of existence is to turn away from the eternal and divine. Here, the category of the material is assimilated to that of sin or evil.
  • Yet in fact this feature of Marxist philosophical classification is one that, with some variations, continues to be shared by all philosophers, even in the West, even today
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  • materialism is not the greedy desire for material goods, but rather the belief that the fundamental reality of the world is material;
  • idealism is not the aspiration toward lofty and laudable goals, but rather the belief that the fundamental reality of the world is mental or idea-like. English-speaking philosophers today tend to speak of “physicalism” or “naturalism” rather than materialism (perhaps to avoid confusion with the Wall Street sense of the term). At the same time, Anglo-American historians of philosophy continue to find the distinction between materialism and idealism a useful one in our attempts at categorizing past schools of thought. Democritus and La Mettrie were materialists; Hobbes was pretty close. Berkeley and Kant were idealists; Leibniz may have been.
  • And it was these paradoxes that led the Irish philosopher to conclude that talk of matter was but a case of multiplying entities beyond necessity. For Berkeley, all we can know are ideas, and for this reason it made sense to suppose that the world itself consists in ideas.
  • Soviet and Western Marxists alike, by stark contrast, and before them the French “vulgar” (i.e., non-dialectical) materialists of the 18th century, saw and see the material world as the base and cause of all mental activity, as both bringing ideas into existence, and also determining the form and character of a society’s ideas in accordance with the state of its technology, its methods of resource extraction and its organization of labor. So here to focus on the material is not to become distracted from the true source of being, but rather to zero right in on it.
  • one great problem with the concept of materialism is that it says very little in itself. What is required in addition is an elaboration of what a given thinker takes matter, or ideas, to be. It may not be just the Marxist aftertaste, but also the fact that the old common-sense idea about matter as brute, given stuff has turned out to have so little to do with the way the physical world actually is, that has led Anglo-American philosophers to prefer to associate themselves with the “physical” or the “natural” rather than with the material.  Reality, they want to say, is just what is natural, while everything else is in turn “supernatural” (this distinction has its clarity going for it, but it also seems uncomfortably close to tautology). Not every philosopher has a solid grasp of subatomic physics, but most know enough to grasp that, even if reality is eventually exhaustively accounted for through an enumeration of the kinds of particles and a few basic forces, this reality will still look nothing like what your average person-in-the-street takes reality to be.
  • The 18th-century idealist philosopher George Berkeley strongly believed that matter was only a fiction contrived by philosophers in the first place, for which the real people had no need. For Berkeley, there was never anything common-sensical about matter. We did not need to arrive at the era of atom-splitting and wave-particle duality, then, in order for the paradoxes inherent in matter to make themselves known (is it infinitely divisible or isn’t it?
  • Central to this performance was the concept of  “materialism.” The entire history of philosophy, in fact, was portrayed in Soviet historiography as a series of matches between the materialist home-team and its “idealist” opponents, beginning roughly with Democritus (good) and Plato (bad), and culminating in the opposition between official party philosophy and logical positivism, the latter of which was portrayed as a shrouded variety of idealism. Thus from the “Short Philosophical Dictionary,” published in Moscow in 1951, we learn that the school of logical empiricism represented by Rudolf Carnap, Otto Neurath and others, “is a form of subjective idealism, characteristic of degenerating bourgeois philosophy in the epoch of the decline of capitalism.”Now the Soviet usage of this pair of terms appears to fly in the face of our ordinary, non-philosophical understanding of them (that, for example,  Wall Street values are “materialist,” while the Occupy movement is “idealist”). One might have thought that the communists should be flinging the “materialist” label at their capitalist enemies, rather than claiming it for themselves. One might also have thought that the Bolshevik Revolution and the subsequent failed project of building a workers’ utopia was nothing if not idealistic.
  • Consider money. Though it might sometimes be represented by bank notes or coins, money is an immaterial thing par excellence, and to seek to acquire it is to move on the plane of ideas. Of course, money can also be converted into material things, yet it seems simplistic to suppose that we want money only in order to convert it into the material things we really want, since even these material things aren’t just material either: they are symbolically dense artifacts, and they convey to others certain ideas about their owners. This, principally, is why their owners want them, which is to say that materialists (in the everyday sense) are trading in ideas just as much as anyone else.
  • In the end no one really cares about stuff itself. Material acquisitions — even, or perhaps especially, material acquisitions of things like Rolls Royces and Rolexes — are maneuvers within a universe of materially instantiated ideas. This is human reality, and it is within this reality that mystics, scientists, and philosophers alike are constrained to pursue their various ends, no matter what they might take the ultimate nature of the external world to be.
  •  
    A very interesting article on the contrast between materialism and idealism.
Ellie McGinnis

The Dangers of Pseudoscience - NYTimes.com - 0 views

  • “demarcation problem,” the issue of what separates good science from bad science and pseudoscience
  • Demarcation is crucial to our pursuit of knowledge; its issues go to the core of debates on epistemology and of the nature of truth and discovery
  • our society spends billions of tax dollars on scientific research, so it is important that we also have a good grasp of what constitutes money well spent in this regard
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  • pseudoscience is not — contrary to popular belief — merely a harmless pastime of the gullible; it often threatens people’s welfare, sometimes fatally so
  • in the area of medical treatments that the science-pseudoscience divide is most critical, and where the role of philosophers in clarifying things may be most relevant
  • What makes the use of aspirin “scientific,” however, is that we have validated its effectiveness through properly controlled trials, isolated the active ingredient, and understood the biochemical pathways through which it has its effects
  • inaccessibility of the famous Higgs boson, a sub-atomic particle postulated by physicists to play a crucial role in literally holding the universe together (it provides mass to all other particles)
  • Philosophers of science have long recognized that there is nothing wrong with positing unobservable entities per se, it’s a question of what work such entities actually do within a given theoretical-empirical framework.
  • we are attempting to provide explanations for why some things work and others don’t. If these explanations are wrong, or unfounded as in the case of vacuous concepts like Qi, then we ought to correct or abandon them.
  • no sharp line dividing sense from nonsense, and moreover that doctrines starting out in one camp may over time evolve into the other.
  • Popper’s basic insight: the bad habit of creative fudging and finagling with empirical data ultimately makes a theory impervious to refutation. And all pseudoscientists do it, from parapsychologists to creationists and 9/11 Truthers.
  • The open-ended nature of science means that there is nothing sacrosanct in either its results or its methods.
  • The borderlines between genuine science and pseudoscience may be fuzzy, but this should be even more of a call for careful distinctions, based on systematic facts and sound reasoning
Javier E

Technology Provides an Alternative to Love. - NYTimes.com - 0 views

  • They are, however, great allies and enablers of narcissism. Alongside their built-in eagerness to be liked is a built-in eagerness to reflect well on us. Our lives look a lot more interesting when they’re filtered through the sexy Facebook interface.
  • To friend a person is merely to include the person in our private hall of flattering mirrors.
  • There is no such thing as a person whose real self you like every particle of. This is why a world of liking is ultimately a lie. But there is such a thing as a person whose real self you love every particle of. And this is why love is such an existential threat to the techno-consumerist order: it exposes the lie.
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  • When you consider the alternative — an anesthetized dream of self-sufficiency, abetted by technology — pain emerges as the natural product and natural indicator of being alive in a resistant world. To go through a life painlessly is to have not lived.
Javier E

Lab Claims Faster-Than-Light Particle - NYTimes.com - 0 views

  • Hundreds of scientists packed an auditorium at one of the world's foremost laboratories on the Swiss-French border to hear how a subatomic particle, the neutrino, was found to have outrun light and confounded the theories of Albert Einstein.
  • Going faster than light is something that is just not supposed to happen, according to Einstein's 1905 special theory of relativity. The speed of light — 186,282 miles per second (299,792 kilometers per second) — has long been considered a cosmic speed limit.
Emily Freilich

Higgs Boson Gets Nobel Prize, But Physicists Still Don't Know What It's Telling Them - ... - 2 views

  • This morning, two physicists who 50 years ago theorized the existence of this particle, which is responsible for conferring mass to all other known particles in the universe, got the Nobel, the highest prize in science.
  • left physicists without a clear roadmap of where to go next
  • No one is sure which of these models, if any, will eventually describe reality
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  • Some of them look at the data and say that we need to throw out speculative ideas such as supersymmetry and the multiverse, models that look elegant mathematically but are unprovable from an experimental perspective. Others look at the exact same data and come to the opposite conclusion.
  • we’ve entered a very deep crisis.
  • hough happy to know the Higgs was there, many scientists had hoped it would turn out to be strange, to defy their predictions in some way and give a hint as to which models beyond the Standard Model were correct.
  • One possibility has been brought up that even physicists don’t like to think about. Maybe the universe is even stranger than they think. Like, so strange that even post-Standard Model models can’t account for it. Some physicists are starting to question whether or not our universe is natural.
  • The multiverse idea has two strikes against it, though. First, physicists would refer to it as an unnatural explanation because it simply happened by chance. And second, no real evidence for it exists and we have no experiment that could currently test for it.
  • physicists are still in the dark. We can see vague outlines ahead of us but no one knows what form they will take when we reach them.
Javier E

The Reality of Quantum Weirdness - NYTimes.com - 1 views

  • Is there a true story, or is our belief in a definite, objective, observer-independent reality an illusion?
  • a paper published online in the journal Nature Physics presents experimental research that supports the latter scenario — that there is a “Rashomon effect” not just in our descriptions of nature, but in nature itself.
  • The electron appears to be a strange hybrid of a wave and a particle that’s neither here and there nor here or there. Like a well-trained actor, it plays the role it’s been called to perform
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  • Is nature really this weird? Or is this apparent weirdness just a reflection of our imperfect knowledge of nature?
  • The answer depends on how you interpret the equations of quantum mechanics, the mathematical theory that has been developed to describe the interactions of elementary particles. The success of this theory is unparalleled: Its predictions, no matter how “spooky,” have been observed and verified with stunning precision. It has also been the basis of remarkable technological advances. So it is a powerful tool. But is it also a picture of reality?
  • Does the wave function directly correspond to an objective, observer-independent physical reality, or does it simply represent an observer’s partial knowledge of it?
  • If there is an objective reality at all, the paper demonstrates, then the wave function is in fact reality-based.
  • What this research implies is that we are not just hearing different “stories” about the electron, one of which may be true. Rather, there is one true story, but it has many facets, seemingly in contradiction, just like in “Rashomon.” There is really no escape from the mysterious — some might say, mystical — nature of the quantum world.
  • We should be careful to recognize that the weirdness of the quantum world does not directly imply the same kind of weirdness in the world of everyday experience.
  • This is why, in fact, we are able to describe the objects around us in the language of classical physics.
  • I suggest that we regard the paradoxes of quantum physics as a metaphor for the unknown infinite possibilities of our own existence.
Javier E

A New Alternative to Dark Matter - The Atlantic - 0 views

  • The challenges for alternative gravity theories—collectively known as modified Newtonian dynamics, or MOND—were spelled out in a separate preprint coincidentally published the day after the new model appeared. Chief among them is recasting the leading role dark matter plays in drawing the universe together, as described by a well-established cosmological model known as LCDM, or Lambda cold dark matter.
  • Simply put, LCDM says that we wouldn’t be here without dark matter. The infant universe was so smooth that the gravitational attraction of ordinary matter alone wouldn’t have been enough to gather particles into galaxies, stars, and planets. Enter dark-matter particles. Under the LCDM model, their collective bulk sculpts normal matter into the modern cosmic structures studied by astronomers.
  • LCDM became the standard model of cosmology in part because it so precisely agrees with the CMB. This map of the early universe shows almost imperceptibly thick and thin spots rippling through the cosmos. More recently, researchers have been able to measure the orientation or polarization of the CMB’s light more precisely. Any successful cosmology will need to establish a comprehensive history of the cosmos by reproducing these three observations: the CMB’s temperature, the CMB’s polarization, and the current distribution of galaxies and galaxy clusters.
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  • Recreating these and other features without LCDM’s titular ingredient, Spergel showed, requires the finest of theoretical needle threading. “We haven’t disproven the existence of all these [modified-gravity theories],” he says. “But any alternative theory has to jump through these hoops.”
  • Złosnik and Skordis believe they’ve done just that—although in a way that might surprise MOND skeptics and fans alike. They managed to construct a theory of gravity that contains an ingredient that acts exactly like an invisible form of matter on cosmic scales, blurring the line between the dark matter and MOND paradigms.
  • Their theory, dubbed RelMOND, adds to the equations of general relativity an omnipresent field that behaves differently in different arenas. On the grandest scales, where the universe noticeably stretches as it expands, the field acts like invisible matter. In this mode, which Złosnik calls “dark dust,” the field could have shaped the visible universe just as dark matter would
  • RelMOND “cannot do worse than LCDM,” says Złosnik, who notes that it very closely mimics that theory for the universe as a whole.
  • But if we zoom in on a galaxy, where the fabric of space holds rather still, the field acts in a way that’s true to its MOND roots: It entwines itself with the standard gravitational field, beefing it up just enough to hold a galaxy together without extra matter
  • (The researchers aren’t yet sure how the field acts for larger clusters of galaxies, a perennial MOND sore spot. They suggest that this intermediate scale might be a good place to look for observational clues that could set the theory apart.)
  • Despite this mathematical achievement by Złosnik and Skordis, dark matter remains the simpler theory. Constructing the new field takes four new moving mathematical parts, while LCDM handles dark matter with just one. Hooper likens the situation to a detective debating whether a person at a murder scene is the murderer or has been framed by the CIA. Even if the available evidence matches both theories, one requires less of a leap.
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