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katrinaskibicki

Revolutionary discovery: Scientists find gravitational waves Einstein predicted - 0 views

  • For the first time ever, scientists have directly detected gravitational waves, bizarre ripples in space-time foreseen by Einstein a century ago. The discovery was the final, acid test of Einstein’s general theory of relativity.
  • Einstein has been proven right – again.For the first time ever, scientists have directly detected gravitational waves, bizarre ripples in space-time foreseen by Einstein a century ago. The discovery was the final, acid test of Einstein’s celebrated general theory of relativity, and once again Einstein’s genius held up to scrutiny.
  • The waves in question arose during the close approach of two black holes some 1.3 billion years ago, when multicellular life began to spread on Earth. Traveling at the speed of light, the waves reached our planet in September -- precisely when a observatory built to detect them was emerging from a long hiatus.
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  • When scientists first saw the data suggesting that they’d captured a gravitational wave, they thought the results seemed to good to be true. Past claims of gravitational waves have proven unreliable, and there are many possible sources of error.
  • Gravitational waves confirmedAstrophysicists have announced the discovery of gravitational waves, ripples that travel at the speed of light through the fabric of space-time. A 1916 theory of Albert Einstein’s predicted their existence. .oembed-asset-photo-image { width: 100%; }
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    A new scientific discovery shows that Einstein's predictions were correct, yet again!
carolinewren

'It Is Climate Change': India's Heat Wave Now The 5th Deadliest In World History | Thin... - 0 views

  • searing and continuing heat wave in India has so far killed more than 2,300 people, making it the 5th deadliest in recorded world history.
  • As temperatures soared up to 113.7 degrees Fahrenheit and needed monsoon rains failed to materialize, the country’s minister of earth sciences did not mince words about what he says is causing the disaster.
  • “Let us not fool ourselves that there is no connection between the unusual number of deaths from the ongoing heat wave and the certainty of another failed monsoon,” Harsh Vardhan said, according to Reuters. “It’s not just an unusually hot summer, it is climate change.”
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  • “Attribution of events to climate change is still emerging as a science, but recent and numerous studies continue to speak to heat waves having strong links to warming climate,”
  • India is getting hotter as humans continue to pump carbon dioxide into the atmosphere. With these increases in heat, the report — produced by 1,250 international experts and approved by every major government in the world — said with high confidence that the risk of heat-related mortality would rise due to climate change and population increases, along with greater risk of drought-related water and food shortages.
  • extreme heat events “have become as much as 10 times more likely due to the current cumulative effects of human-induced climate change.”
  • Mann said that as climate change threatens to worsen as more carbon is emitted into the atmosphere, heat events once considered extreme would become relatively common. He noted that India’s nearly unprecedented deadly heat wave is occurring at current global warming levels of just 1.5 degrees Fahrenheit — so heat waves occurring under the “business as usual” global warming scenario that sees average temperatures rise 7 to 9 degrees by the end of the century would be much, much worse
  • The impacts of climate change are widely expected to be more harmful in poor countries than in their fully developed counterparts.
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
  • using tiny bubbles of helium as physical “traps.
  • trapping the chance of finding the electron, not pieces of the electron
  • 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.
  • 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.”
nataliedepaulo1

Beating Alzheimer's With Brain Waves - The Atlantic - 0 views

  • These waves are classified by how frequently the neurons fire in a single second. If they fire one to four times, that’s a delta wave, which occurs during deep sleep. If they fire 12 to 30 times, that’s a beta wave, which is typical of normal wakefulness. And if they do so 30 to 90 times, that’s a gamma wave, which has been linked to higher mental abilities, like memory, attention, and perception. It’s no surprise, then, that scientists have seen disrupted gamma waves in many types of brain disorders, including injuries, schizophrenia, and Alzheimer’s disease
  • This is still preliminary work, but it heralds a completely new approach to dealing with Alzheimer’s—changing neural activity, rather than delivering drugs or chemicals. “It’s so different from what people have tried, but we are very excited about the possibility of bringing this to human testing,” says Li-Huei Tsai, an MIT researcher who led the study.
Javier E

Covid-19 expert Karl Friston: 'Germany may have more immunological "dark matter"' | Wor... - 0 views

  • Our approach, which borrows from physics and in particular the work of Richard Feynman, goes under the bonnet. It attempts to capture the mathematical structure of the phenomenon – in this case, the pandemic – and to understand the causes of what is observed. Since we don’t know all the causes, we have to infer them. But that inference, and implicit uncertainty, is built into the models
  • That’s why we call them generative models, because they contain everything you need to know to generate the data. As more data comes in, you adjust your beliefs about the causes, until your model simulates the data as accurately and as simply as possible.
  • A common type of epidemiological model used today is the SEIR model, which considers that people must be in one of four states – susceptible (S), exposed (E), infected (I) or recovered (R). Unfortunately, reality doesn’t break them down so neatly. For example, what does it mean to be recovered?
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  • SEIR models start to fall apart when you think about the underlying causes of the data. You need models that can allow for all possible states, and assess which ones matter for shaping the pandemic’s trajectory over time.
  • These techniques have enjoyed enormous success ever since they moved out of physics. They’ve been running your iPhone and nuclear power stations for a long time. In my field, neurobiology, we call the approach dynamic causal modelling (DCM). We can’t see brain states directly, but we can infer them given brain imaging data
  • Epidemiologists currently tackle the inference problem by number-crunching on a huge scale, making use of high-performance computers. Imagine you want to simulate an outbreak in Scotland. Using conventional approaches, this would take you a day or longer with today’s computing resources. And that’s just to simulate one model or hypothesis – one set of parameters and one set of starting conditions.
  • Using DCM, you can do the same thing in a minute. That allows you to score different hypotheses quickly and easily, and so to home in sooner on the best one.
  • This is like dark matter in the universe: we can’t see it, but we know it must be there to account for what we can see. Knowing it exists is useful for our preparations for any second wave, because it suggests that targeted testing of those at high risk of exposure to Covid-19 might be a better approach than non-selective testing of the whole population.
  • Our response as individuals – and as a society – becomes part of the epidemiological process, part of one big self-organising, self-monitoring system. That means it is possible to predict not only numbers of cases and deaths in the future, but also societal and institutional responses – and to attach precise dates to those predictions.
  • How well have your predictions been borne out in this first wave of infections?For London, we predicted that hospital admissions would peak on 5 April, deaths would peak five days later, and critical care unit occupancy would not exceed capacity – meaning the Nightingale hospitals would not be required. We also predicted that improvements would be seen in the capital by 8 May that might allow social distancing measures to be relaxed – which they were in the prime minister’s announcement on 10 May. To date our predictions have been accurate to within a day or two, so there is a predictive validity to our models that the conventional ones lack.
  • What do your models say about the risk of a second wave?The models support the idea that what happens in the next few weeks is not going to have a great impact in terms of triggering a rebound – because the population is protected to some extent by immunity acquired during the first wave. The real worry is that a second wave could erupt some months down the line when that immunity wears off.
  • the important message is that we have a window of opportunity now, to get test-and-trace protocols in place ahead of that putative second wave. If these are implemented coherently, we could potentially defer that wave beyond a time horizon where treatments or a vaccine become available, in a way that we weren’t able to before the first one.
  • We’ve been comparing the UK and Germany to try to explain the comparatively low fatality rates in Germany. The answers are sometimes counterintuitive. For example, it looks as if the low German fatality rate is not due to their superior testing capacity, but rather to the fact that the average German is less likely to get infected and die than the average Brit. Why? There are various possible explanations, but one that looks increasingly likely is that Germany has more immunological “dark matter” – people who are impervious to infection, perhaps because they are geographically isolated or have some kind of natural resistance
  • Any other advantages?Yes. With conventional SEIR models, interventions and surveillance are something you add to the model – tweaks or perturbations – so that you can see their effect on morbidity and mortality. But with a generative model these things are built into the model itself, along with everything else that matters.
  • Are generative models the future of disease modelling?That’s a question for the epidemiologists – they’re the experts. But I would be very surprised if at least some part of the epidemiological community didn’t become more committed to this approach in future, given the impact that Feynman’s ideas have had in so many other disciplines.
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”).
grayton downing

Measuring Consciousness | The Scientist Magazine® - 0 views

  • General anesthesia has transformed surgery from a ghastly ordeal to a procedure in which the patient feels no pain.
  • “integrated-information theory,” which holds that consciousness relies on communication between different brain areas, and fades as that communication breaks down.
  • neural markers of consciousness—or more precisely, the loss of consciousness—a group led by Patrick Purdon
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  • The purpose of the surgery was to remove electrodes that had previously been implanted in the patients’ brains to monitor seizures. But before they were taken out, the electrodes enabled the researchers to study the activity of individual neurons in the cortex, in addition to large-scale brain activity from EEG recordings.
  • importance of communication between discrete groups of neurons, both within the cortex and across brain regions, is analogous to a band playing music, said George Mashour, a neuroscientist and anesthesiologist at the University of Michigan, Ann Arbor. “You need musical information to come together either in time or space to really make sense,”
  • “Consciousness and cognitive activity may be similar. If different areas of the brain aren’t in synch or if a critical area that normally integrates cognitive activity isn’t functioning, you could be rendered unconscious.”
  • , Purdon and colleagues were able to discern a more detailed neural signature of loss of unconsciousness, this time by using EEG alone. Monitoring brain activity in healthy patients for 2 hours as they underwent propofol-induced anesthesia, they observed that as responsiveness fades, high-frequency brain waves (12–35 hertz) rippling across the cortex and the thalamus were replaced by two different brain waves superimposed on top on one another: a low-frequency (<1 hertz) wave and an alpha frequency (8–12 hertz) wave. “These two waves pretty much come at loss of consciousness,”
  • “We’ve started to teach our anesthesiologists how to read this signature on the EEG”
  • Anesthesia is not the only state in which consciousness is lost, of course
  • o measure the gradual breakdown of connectivity between neural networks during natural REM sleep and anesthesia, as well as in brain-injured, unresponsive patients. Using an electromagnetic coil to activate neurons in a small patch of the human cortex, then recording EEG output to track the propagation of those signals to other neuronal groups, the researchers can measure the connectivity between collections of neurons in the cortex and other brain regions.
  • minimally conscious patients, the magnetically stimulated signals propagated fairly far and wide, occasionally reaching distant cortical areas, much like activations seen in locked-in but conscious patients. In patients in a persistent vegetative state, on the other hand, propagation was severely limited—a breakdown of connectivity similar to that observed in previous tests of anesthetized patients. What’s more, in three vegetative patients that later recovered consciousness, the test picked up signs of increased connectivity before clinical signs of improvement became evident.
  • “I think understanding consciousness itself is going to help us find successful [measurement] approaches that are universally applicable,” said Pearce.
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!
manhefnawi

Brain waves may focus attention and keep information flowing | Science News - 0 views

  • We can’t see it, but brains hum with electrical activity. Brain waves created by the coordinated firing of huge collections of nerve cells pinball around the brain. The waves can ricochet from the front of the brain to the back, or from deep structures all the way to the scalp and then back again.
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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  • 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.
  • “This is a revolution not unlike the early days of computing,” he said. “It is a transformation in the way computers are thought about.”
  • 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.
  • 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.
sissij

The Wave (2008 film) - Wikipedia, the free encyclopedia - 1 views

  • Ron Jones's "Third Wave" experiment, which took place at a Californian school in 1967. Because his students did not understand how something like national socialism could even happen, he founded a totalitarian, strictly-organized "movement" with harsh punishments that was led by him autocratically. The intricate sense of community led to a wave of enthusiasm not only from his own students, but also from students from other classes who joined the program later. Jones later admitted to having enjoyed having his students as followers. To eliminate the upcoming momentum, Jones aborted the project on the fifth day and showed the students the parallels towards the Nazi youth movements.[3][4]
  • “Therein lies the great danger. It is an interesting fact that we always believe that what happens to others would never happen to us. We blame others, for example the less educated or the East Germans etc. However, in the Third Reich the house caretaker was just as fascinated by the movement as was the intellectual.”[10]
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    I think this experiment is very interesting because it shows a flaw in human thinking that we are always progressing. However, just like the quote says: "Barbarism is not the inheritance of our pre-history. It is the companion that dogs our every step." The film "Die Welle", based on this experiment, is also very interesting and worth-watching. --Sissi (Sept 17, 2016)
maxwellokolo

Sound waves could take a tsunami down a few notches - 0 views

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    Acoustic-gravity waves would exchange energy with destructive water wave A tsunami's immense wall of water may not be stoppable. But there may be a way to take the ferocious force of nature down a few notches, using a pair of counterwaves.
anonymous

Holding hands can sync brainwaves, ease pain, study shows -- ScienceDaily - 0 views

  • Reach for the hand of a loved one in pain and not only will your breathing and heart rate synchronize with theirs, your brain wave patterns will couple up too, according to a study published this week in the Proceedings of the National Academy of Sciences (PNAS).The study, by researchers with the University of Colorado Boulder and University of Haifa, also found that the more empathy a comforting partner feels for a partner in pain, the more their brainwaves fall into sync. And the more those brain waves sync, the more the pain goes away.
  • The study is the latest in a growing body of research exploring a phenomenon known as "interpersonal synchronization," in which people physiologically mirror the people they are with. It is the first to look at brain wave synchronization in the context of pain, and offers new insight into the role brain-to-brain coupling may play in touch-induced analgesia, or healing touch.
  • He and his colleagues at University of Haifa recruited 22 heterosexual couples, age 23 to 32 who had been together for at least one year and put them through several two-minute scenarios as electroencephalography (EEG) caps measured their brainwave activity. The scenarios included sitting together not touching; sitting together holding hands; and sitting in separate rooms. Then they repeated the scenarios as the woman was subjected to mild heat pain on her arm.Merely being in each other's presence, with or without touch, was associated with some brain wave synchronicity in the alpha mu band, a wavelength associated with focused attention. If they held hands while she was in pain, the coupling increased the most.
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  • The study did not explore whether the same effect would occur with same-sex couples, or what happens in other kinds of relationships. The takeaway for now, Pavel said: Don't underestimate the power of a hand-hold."You may express empathy for a partner's pain, but without touch it may not be fully communicated," he said.
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.
  • 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.”
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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
  • The strange implication is that the reality of the quantum world remains amorphous or indefinite until scientists start measuring
  • 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.”
  • “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.
  • 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.
  • 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.
  • 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.”
tongoscar

https://www.cbc.ca/news/technology/climate-2019-1.5427586 - 0 views

  • Climate change is costing cities as they try to adapt and mitigate. Farmers are facing increasing challenges, which can lead to consumers paying more for food.
  • "In my line of work, we do track the numbers and we do try to quantify the behaviour of the climate system, but ultimately what really matters is where it intersects and impacts with the people we love and the things we do," said Deke Arndt, chief of the global monitoring branch of NOAA's National Centers for Environmental Information (NCEI).
  • "Some people who work in weather-sensitive sectors such as agriculture … are seeing [climate change] on an annual basis, and they're seeing [it] through greater extremes,
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  • The fires raging in Australia are just a recent example of the challenges a continuously warming Earth will present. To date, 28 people have died, including two firemen, and millions of animals are thought to have perished.  Then there are hurricanes. In 2019, Hurricane Dorian sat almost immovable above Abaco Island in the Bahamas for more almost 24 hours, killing at least 70 people. Heat waves killed an estimated 1,500 people in France in 2019. The good news is this is far below the 2003 heat wave that killed an estimated 30,000 across Europe, with 14,000 in France alone. And here at home, a heat wave killed 66 people in Montreal in 2018.
katherineharron

A blob of hot ocean water killed a million seabirds, scientists say - CNN - 0 views

  • As many as one million seabirds died at sea in less than 12 months in one of the largest mass die-offs in recorded history -- and researchers say warm ocean waters are to blame.
  • The birds, a fish-eating species called the common murre, were severely emaciated and appeared to have died of starvation between the summer of 2015 and the spring of 2016, washing up along North America's west coast, from California to Alaska.
  • The heat wave created the Blob -- a 1,000-mile (1,600 km) stretch of ocean that was warmed by 3 to 6 degrees Celsius (5.4 to 10.8 Fahrenheit). A high-pressure ridge calmed the ocean waters -- meaning heat stays in the water, without storms to help cool it down.
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  • Other animals that experienced mass die-offs include sea lions, tufted puffins, and baleen whales. But none of them compared to the murres in scale.
  • The murres likely starved to death because the Blob caused more competition for fewer small prey. The warming increased the metabolism of predatory fish like salmon, cod, and halibut -- meaning they were eating more than usual. These fish eat the same small fish as the murres, and there simply wasn't enough to go around.
  • During the 2015 breeding season, three colonies didn't produce a single chick. That number went up to 12 colonies in the 2016 season -- and in reality it could be even higher, since researchers only monitor a quarter of all colonies.
  • It's especially rare to see a patch of warm ocean water over such a large area, but scientists say global climate change is making these phenomena more common. From 1982 to 2016, there was an 82% rise in the number of heat wave days on the global ocean surface, according to a 2018 study. That's because heat waves are increasing in both frequency and duration, with the highest level of maritime heat wave activity occurring in the North Atlantic
kirkpatrickry

Second Wave Positive Psychology - 0 views

  • I think it’s recognising that things that we might deem to be negative can still serve flourishing and adaptation and wellbeing, so it can perhaps expand our way, expand our horizons and concern in the field.”
  • the second wave is an important and exciting development for the field of positive psychology, which can help it to become a more mature and well-rounded discipline. By focusing research on both the positive and the negative as ways for people to flourish, this allows for a broader scope of interventions for people to use, in order to thrive and be successful.
Javier E

The Anger Wave That May Just Wipe Out Laissez-Faire Economics - The New York Times - 1 views

  • few would have guessed that the economic order built upon Mr. Reagan’s and Mrs. Thatcher’s common faith in unfettered global markets (and largely accepted by their more liberal successors Bill Clinton and Tony Blair) would be brought down by right-wing populists riding the anger of a working class that has been cast aside in the globalized economy that the two leaders trumpeted 40 years ago.
  • The so-called Brexit vote was driven by an inchoate sense among older white workers with modest education that they have been passed over, condemned by forces beyond their control to an uncertain job for little pay in a world where their livelihoods are challenged not just by cheap Asian workers halfway around the world, but closer to home by waves of immigrants of different faiths and skin tones.
  • It is the same frustration that has buoyed proto-fascist political parties across Europe. It is the same anger fueling the candidacy of Mr. Trump in the United States.
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  • Mr. Trump, the bombastic businessman who’s never held office, and Mr. Johnson, the former journalist turned mayor of London, might not put it this way, since they continue to cling to a conservative mantle. But they are riding a revolt of the working class against a 40-year-long project of the political right and its corporate backers that has dominated policy making in the English-speaking world for a generation.
  • The British political scientist Andrew Gamble at the University of Cambridge has argued that Western capitalism has experienced two transformational crises since the end of the 19th century. The first, brought about by the Depression of the 1930s, ended an era in which governments bowed to the gospel of the gold standard and were expected to butt out of the battles between labor and capital, letting markets function on their own, whatever the consequences
  • Mr. Keynes’s views ultimately prevailed, though, providing the basis for a new post-World War II orthodoxy favoring active government intervention in the economy and a robust welfare state. But that era ended when skyrocketing oil prices and economic mismanagement in the 1970s brought about a combination of inflation and unemployment that fatally undermined people’s trust in the state.
  • The Keynesian era ended when Margaret Thatcher and Ronald Reagan rode onto the scene with a version of capitalism based on tax cuts, privatization and deregulation that helped revive their engines of growth but led the workers of the world to the deeply frustrating, increasingly unequal economy of today.
  • After the Brexit vote, Lawrence Summers, former Treasury secretary under President Clinton and one of President Obama’s top economic advisers at the nadir of the Great Recession, laid out an argument for what he called “responsible nationalism,” which focused squarely on the interests of domestic workers.
  • Instead of negotiating more agreements to ease business across borders, governments would focus on deals to improve labor and environmental standards internationally. They might cut deals to prevent cross-border tax evasion.
  • There is, however, little evidence that the world’s leaders will go down that path. Despite the case for economic stimulus, austerity still rules across much of the West. In Europe, most governments have imposed stringent budget cuts — ensuring that all but the strongest economies would stall. In the United States, political polarization has brought fiscal policy — spending and taxes — to a standstill.
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

Opinion | Even Physicists Don't Understand Quantum Mechanics - The New York Times - 2 views

  • “I think I can safely say that nobody really understands quantum mechanics,” observed the physicist and Nobel laureate Richard Feynman.
  • What’s surprising is that physicists seem to be O.K. with not understanding the most important theory they have.
  • Scientists can use quantum mechanics with perfect confidence. But it’s a black box. We can set up a physical situation, and make predictions about what will happen next that are verified to spectacular accuracy. What we don’t do is claim to understand quantum mechanics
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  • There are two problems. One is that quantum mechanics, as it is enshrined in textbooks, seems to require separate rules for how quantum objects behave when we’re not looking at them, and how they behave when they are being observed
  • Why are observations special? What counts as an “observation,” anyway? When exactly does it happen? Does it need to be performed by a person? Is consciousness somehow involved in the basic rules of reality?
  • Together these questions are known as the “measurement problem” of quantum theory.
  • The other problem is that we don’t agree on what it is that quantum theory actually describes, even when we’re not performing measurements.
  • We describe a quantum object such as an electron in terms of a “wave function,” which collects the superposition of all the possible measurement outcomes into a single mathematical object
  • But what is the wave function? Is it a complete and comprehensive representation of the world? Or do we need additional physical quantities to fully capture reality, as Albert Einstein and others suspected? Or does the wave function have no direct connection with reality at all, merely characterizing our personal ignorance about what we will eventually measure in our experiments?
  • For years, the leading journal in physics had an explicit policy that papers on the foundations of quantum mechanics were to be rejected out of hand
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