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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!”

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.

One common strategy for thinking about this is to suggest that what we used to call the whole universe is just a small part of everything there is, and that we live in a kind of bubble universe, a small region of something much larger

Newton realized there had to be some force holding the moon in its orbit around the earth, to keep it from wandering off, and he knew also there was a force that was pulling the apple down to the earth. And so what suddenly struck him was that those could be one and the same thing, the same force

That was a physical discovery, a physical discovery of momentous importance, as important as anything you could ever imagine because it knit together the terrestrial realm and the celestial realm into one common physical picture. It was also a philosophical discovery in the sense that philosophy is interested in the fundamental natures of things.

There are other ideas, for instance that maybe there might be special sorts of laws, or special sorts of explanatory principles, that would apply uniquely to the initial state of the universe.

The basic philosophical question, going back to Plato, is "What is x?" What is virtue? What is justice? What is matter? What is time? You can ask that about dark energy - what is it? And it's a perfectly good question.

right now there are just way too many freely adjustable parameters in physics. Everybody agrees about that. There seem to be many things we call constants of nature that you could imagine setting at different values, and most physicists think there shouldn't be that many, that many of them are related to one another. Physicists think that at the end of the day there should be one complete equation to describe all physics, because any two physical systems interact and physics has to tell them what to do. And physicists generally like to have only a few constants, or parameters of nature. This is what Einstein meant when he famously said he wanted to understand what kind of choices God had --using his metaphor-- how free his choices were in creating the universe, which is just asking how many freely adjustable parameters there are. Physicists tend to prefer theories that reduce that number

You have others saying that time is just an illusion, that there isn't really a direction of time, and so forth. I myself think that all of the reasons that lead people to say things like that have very little merit, and that people have just been misled, largely by mistaking the mathematics they use to describe reality for reality itself. If you think that mathematical objects are not in time, and mathematical objects don't change -- which is perfectly true -- and then you're always using mathematical objects to describe the world, you could easily fall into the idea that the world itself doesn't change, because your representations of it don't.

physicists for almost a hundred years have been dissuaded from trying to think about fundamental questions. I think most physicists would quite rightly say "I don't have the tools to answer a question like 'what is time?' - I have the tools to solve a differential equation." The asking of fundamental physical questions is just not part of the training of a physicist anymore.

The question remains as to how often, after life evolves, you'll have intelligent life capable of making technology. What people haven't seemed to notice is that on earth, of all the billions of species that have evolved, only one has developed intelligence to the level of producing technology. Which means that kind of intelligence is really not very useful. It's not actually, in the general case, of much evolutionary value. We tend to think, because we love to think of ourselves, human beings, as the top of the evolutionary ladder, that the intelligence we have, that makes us human beings, is the thing that all of evolution is striving toward. But what we know is that that's not true. Obviously it doesn't matter that much if you're a beetle, that you be really smart. If it were, evolution would have produced much more intelligent beetles. We have no empirical data to suggest that there's a high probability that evolution on another planet would lead to technological intelligence.

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.

it is as if two magic coins, flipped at different corners of the cosmos, always came up heads or tails together. (The spooky action takes place only in the context of simultaneous measurement. The particles share states, but they don’t send signals.)

fashion, temperament, zeitgeist, and sheer tenacity affected the debate, along with evidence and argument.

The certainty that spooky action at a distance takes place, Musser says, challenges the very notion of “locality,” our intuitive sense that some stuff happens only here, and some stuff over there. What’s happening isn’t really spooky action at a distance; it’s spooky distance, revealed through an action.

Why, then, did Einstein’s question get excluded for so long from reputable theoretical physics? The reasons, unfolding through generations of physicists, have several notable social aspects,

What started out as a reductio ad absurdum became proof that the cosmos is in certain ways absurd. What began as a bug became a feature and is now a fact.

“If poetry is emotion recollected in tranquility, then science is tranquility recollected in emotion.” The seemingly neutral order of the natural world becomes the sounding board for every passionate feeling the physicist possesses.

Musser explains that the big issue was settled mainly by being pushed aside. Generational imperatives trumped evidentiary ones. The things that made Einstein the lovable genius of popular imagination were also the things that made him an easy object of condescension. The hot younger theorists patronized him,

There was never a decisive debate, never a hallowed crucial experiment, never even a winning argument to settle the case, with one physicist admitting, “Most physicists (including me) accept that Bohr won the debate, although like most physicists I am hard pressed to put into words just how it was done.”

Arguing about non-locality went out of fashion, in this account, almost the way “Rock Around the Clock” displaced Sinatra from the top of the charts.

The same pattern of avoidance and talking-past and taking on the temper of the times turns up in the contemporary science that has returned to the possibility of non-locality.

the revival of “non-locality” as a topic in physics may be due to our finding the metaphor of non-locality ever more palatable: “Modern communications technology may not technically be non-local but it sure feels that it is.”

Living among distant connections, where what happens in Bangalore happens in Boston, we are more receptive to the idea of such a strange order in the universe.

The “indeterminacy” of the atom was, for younger European physicists, “a lesson of modernity, an antidote to a misplaced Enlightenment trust in reason, which German intellectuals in the 1920’s widely held responsible for their country’s defeat in the First World War.” The tonal and temperamental difference between the scientists was as great as the evidence they called on.

Science isn’t a slot machine, where you drop in facts and get out truths. But it is a special kind of social activity, one where lots of different human traits—obstinacy, curiosity, resentment of authority, sheer cussedness, and a grudging readiness to submit pet notions to popular scrutiny—end by producing reliable knowledge

What was magic became mathematical and then mundane. “Magical” explanations, like spooky action, are constantly being revived and rebuffed, until, at last, they are reinterpreted and accepted. Instead of a neat line between science and magic, then, we see a jumpy, shifting boundary that keeps getting redrawn

Real-world demarcations between science and magic, Musser’s story suggests, are like Bugs’s: made on the move and as much a trap as a teaching aid.

In the past several decades, certainly, the old lines between the history of astrology and astronomy, and between alchemy and chemistry, have been blurred; historians of the scientific revolution no longer insist on a clean break between science and earlier forms of magic.

Where once logical criteria between science and non-science (or pseudo-science) were sought and taken seriously—Karl Popper’s criterion of “falsifiability” was perhaps the most famous, insisting that a sound theory could, in principle, be proved wrong by one test or another—many historians and philosophers of science have come to think that this is a naïve view of how the scientific enterprise actually works.

They see a muddle of coercion, old magical ideas, occasional experiment, hushed-up failures—all coming together in a social practice that gets results but rarely follows a definable logic.

Yet the old notion of a scientific revolution that was really a revolution is regaining some credibility.

David Wootton, in his new, encyclopedic history, “The Invention of Science” (Harper), recognizes the blurred lines between magic and science but insists that the revolution lay in the public nature of the new approach.

What killed alchemy was the insistence that experiments must be openly reported in publications which presented a clear account of what had happened, and they must then be replicated, preferably before independent witnesses.

Wootton, while making little of Popper’s criterion of falsifiability, makes it up to him by borrowing a criterion from his political philosophy. Scientific societies are open societies. One day the lunar tides are occult, the next day they are science, and what changes is the way in which we choose to talk about them.

Wootton also insists, against the grain of contemporary academia, that single observed facts, what he calls “killer facts,” really did polish off antique authorities

once we agree that the facts are facts, they can do amazing work. Traditional Ptolemaic astronomy, in place for more than a millennium, was destroyed by what Galileo discovered about the phases of Venus. That killer fact “serves as a single, solid, and strong argument to establish its revolution around the Sun, such that no room whatsoever remains for doubt,” Galileo wrote, and Wootton adds, “No one was so foolish as to dispute these claims.

everal things flow from Wootton’s view. One is that “group think” in the sciences is often true think. Science has always been made in a cloud of social networks.

There has been much talk in the pop-sci world of “memes”—ideas that somehow manage to replicate themselves in our heads. But perhaps the real memes are not ideas or tunes or artifacts but ways of making them—habits of mind rather than products of mind

science, then, a club like any other, with fetishes and fashions, with schemers, dreamers, and blackballed applicants? Is there a real demarcation to be made between science and every other kind of social activity

The claim that basic research is valuable because it leads to applied technology may be true but perhaps is not at the heart of the social use of the enterprise. The way scientists do think makes us aware of how we can think

So long as we don’t think that the physicists’ space is more fundamental than, or is the ultimate reality of, lived space, then no harm is done.

in contemporary physics, space is curved, or non-Euclidean. In non-Euclidean space, the sum of the angles of a triangle may be greater than 180°; more importantly, the shortest distance between two points may not be a straight line, but a curved one.

When we first hear talk of ‘curved space’ we rebel. The least we should ask of something said to be curved is that it should have edges, surfaces, and parts that look or feel curved, which space itself does not. Analogies are offered to make the idea less counter-intuitive

Physicists will smile at taking the analogy too literally. But if it is not taken literally, it lacks explanatory force. And taken literally, it is seriously misleading. The curvature of an object such as the earth is extrinsic – evident in its surface

From Pythagoras onwards we have been prone to the illusion that our ways of geometrising space capture space itself – perhaps even believing that the mathematical logic of pure quantities is somehow ‘out there’. However, the immense power of mathematical physics – which requires abstracting from phenomenal reality and the reduction of experienced and experienceable reality to mere parameters to which numerical values are assigned – does not justify uncritically accepting concepts such as ‘curved space’ that attempt to re-insert phenomenal appearances into its abstractions. On the contrary, we should acknowledge that ‘unreasonably effective’ mathematics (to borrow Eugene Wigner’s phrase) can take us to places to which nothing non-mathematical corresponds. For instance, consider the assumption, central to modern cosmology, that space itself is expanding.

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.”

There were many new phenomena that were discovered and that came to be understood in the centuries that followed Newton’s era. Take electricity and magnetism, for example. Until the 19th century, we didn’t really know what electricity or magnetism were, or how they worked. Isaac Newton certainly didn’t have a clue.

To many physicists around the turn of the 20th century, the state of physics seemed very settled. The Newtonian worldview had been very successful, and for a very long time.

In 1905, however, a revolution in physics did come. And perhaps even more surprising than the revolution itself was where that revolution came from. In 1905, Albert Einstein was not working as a professor at some prestigious university. He was not famous, or even well-known among other physicists.

Things didn’t stay this way for long, however. In 1905, Einstein wrote not one or two, but four absolutely groundbreaking papers. Any one of these four papers would have made him a star within the field of physics, and would have certainly secured him a position of prominence in the history of science.

It seems that having so many breakthroughs of this magnitude in such a short period of time had never happened before, and has never happened since. In the first of Einstein’s 1905 papers, he proposed that light doesn’t only behave like a wave, but that it is also made up of individual pieces or particles.

But Einstein’s paper provided concrete empirical evidence that atoms were, in fact, real and tangible objects. He was even able to use these arguments to make a pretty good estimate for the size and mass of atoms and molecules. It was a huge step forward.

The equations that physicists use to describe the propagation of light waves—what are known as Maxwell’s equations—predict that light should move through space at a speed of about 670 million miles per hour. And more interestingly, these equations don’t make any reference to any medium that the light waves propagate through.

Although no experiment had ever detected this aether, they argued that it must fill virtually all of space. After all, they argued, the light from a distant star could only reach us if there was a continuous path filled with aether, extending all the way from the star to us.

ventually, though, physicists discovered that there was no aether. It would be Einstein who would come up with an equation to explain this conundrum.

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.”

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

Not only that, but the universe appears to be governed by a kind of cosmic censorship: Regions of extreme gravity—where space-time curves so sharply that Einstein’s equations malfunction and the true, quantum nature of gravity and space-time must be revealed—always hide behind the horizons of black holes.

Dyson, who helped develop quantum electrodynamics (the theory of interactions between matter and light) and is professor emeritus at the Institute for Advanced Study in Princeton, New Jersey, where he overlapped with Einstein, disagrees with the argument that quantum gravity is needed to describe the unreachable interiors of black holes. And he wonders whether detecting the hypothetical graviton might be impossible, even in principle. In that case, he argues, quantum gravity is metaphysical, rather than physics.

The ability to detect the “grin” of quantum gravity would seem to refute Dyson’s argument. It would also kill the gravitational decoherence theory, by showing that gravity and space-time do maintain quantum superpositions.

If gravity is a quantum interaction, then the answer is: It depends. Each component of the blue diamond’s superposition will experience a stronger or weaker gravitational attraction to the red diamond, depending on whether the latter is in the branch of its superposition that’s closer or farther away. And the gravity felt by each component of the red diamond’s superposition similarly depends on where the blue diamond is.

“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.

in general what he argues is that if you take a look at animal cognition, human too, it's computational systems. Therefore, you want to look the units of computation. Think about a Turing machine, say, which is the simplest form of computation, you have to find units that have properties like "read", "write" and "address." That's the minimal computational unit, so you got to look in the brain for those. You're never going to find them if you look for strengthening of synaptic connections or field properties, and so on. You've got to start by looking for what's there and what's working and you see that from Marr's highest level.

it's basically in the spirit of Marr's analysis. So when you're studying vision, he argues, you first ask what kind of computational tasks is the visual system carrying out. And then you look for an algorithm that might carry out those computations and finally you search for mechanisms of the kind that would make the algorithm work. Otherwise, you may never find anything.

"Good Old Fashioned AI," as it's labeled now, made strong use of formalisms in the tradition of Gottlob Frege and Bertrand Russell, mathematical logic for example, or derivatives of it, like nonmonotonic reasoning and so on. It's interesting from a history of science perspective that even very recently, these approaches have been almost wiped out from the mainstream and have been largely replaced -- in the field that calls itself AI now -- by probabilistic and statistical models. My question is, what do you think explains that shift and is it a step in the right direction?

AI and robotics got to the point where you could actually do things that were useful, so it turned to the practical applications and somewhat, maybe not abandoned, but put to the side, the more fundamental scientific questions, just caught up in the success of the technology and achieving specific goals.

The approximating unanalyzed data kind is sort of a new approach, not totally, there's things like it in the past. It's basically a new approach that has been accelerated by the existence of massive memories, very rapid processing, which enables you to do things like this that you couldn't have done by hand. But I think, myself, that it is leading subjects like computational cognitive science into a direction of maybe some practical applicability... ..in engineering? Chomsky: ...But away from understanding.

I was very skeptical about the original work. I thought it was first of all way too optimistic, it was assuming you could achieve things that required real understanding of systems that were barely understood, and you just can't get to that understanding by throwing a complicated machine at it.

if success is defined as getting a fair approximation to a mass of chaotic unanalyzed data, then it's way better to do it this way than to do it the way the physicists do, you know, no thought experiments about frictionless planes and so on and so forth. But you won't get the kind of understanding that the sciences have always been aimed at -- what you'll get at is an approximation to what's happening.

Suppose you want to predict tomorrow's weather. One way to do it is okay I'll get my statistical priors, if you like, there's a high probability that tomorrow's weather here will be the same as it was yesterday in Cleveland, so I'll stick that in, and where the sun is will have some effect, so I'll stick that in, and you get a bunch of assumptions like that, you run the experiment, you look at it over and over again, you correct it by Bayesian methods, you get better priors. You get a pretty good approximation of what tomorrow's weather is going to be. That's not what meteorologists do -- they want to understand how it's working. And these are just two different concepts of what success means, of what achievement is.

if you get more and more data, and better and better statistics, you can get a better and better approximation to some immense corpus of text, like everything in The Wall Street Journal archives -- but you learn nothing about the language.

the right approach, is to try to see if you can understand what the fundamental principles are that deal with the core properties, and recognize that in the actual usage, there's going to be a thousand other variables intervening -- kind of like what's happening outside the window, and you'll sort of tack those on later on if you want better approximations, that's a different approach.

take a concrete example of a new field in neuroscience, called Connectomics, where the goal is to find the wiring diagram of very complex organisms, find the connectivity of all the neurons in say human cerebral cortex, or mouse cortex. This approach was criticized by Sidney Brenner, who in many ways is [historically] one of the originators of the approach. Advocates of this field don't stop to ask if the wiring diagram is the right level of abstraction -- maybe it's no

if you went to MIT in the 1960s, or now, it's completely different. No matter what engineering field you're in, you learn the same basic science and mathematics. And then maybe you learn a little bit about how to apply it. But that's a very different approach. And it resulted maybe from the fact that really for the first time in history, the basic sciences, like physics, had something really to tell engineers. And besides, technologies began to change very fast, so not very much point in learning the technologies of today if it's going to be different 10 years from now. So you have to learn the fundamental science that's going to be applicable to whatever comes along next. And the same thing pretty much happened in medicine.

that's the kind of transition from something like an art, that you learn how to practice -- an analog would be trying to match some data that you don't understand, in some fashion, maybe building something that will work -- to science, what happened in the modern period, roughly Galilean science.

it turns out that there actually are neural circuits which are reacting to particular kinds of rhythm, which happen to show up in language, like syllable length and so on. And there's some evidence that that's one of the first things that the infant brain is seeking -- rhythmic structures. And going back to Gallistel and Marr, its got some computational system inside which is saying "okay, here's what I do with these things" and say, by nine months, the typical infant has rejected -- eliminated from its repertoire -- the phonetic distinctions that aren't used in its own language.

people like Shimon Ullman discovered some pretty remarkable things like the rigidity principle. You're not going to find that by statistical analysis of data. But he did find it by carefully designed experiments. Then you look for the neurophysiology, and see if you can find something there that carries out these computations. I think it's the same in language, the same in studying our arithmetical capacity, planning, almost anything you look at. Just trying to deal with the unanalyzed chaotic data is unlikely to get you anywhere, just like as it wouldn't have gotten Galileo anywhere.

with regard to cognitive science, we're kind of pre-Galilean, just beginning to open up the subject

You can invent a world -- I don't think it's our world -- but you can invent a world in which nothing happens except random changes in objects and selection on the basis of external forces. I don't think that's the way our world works, I don't think it's the way any biologist thinks it is. There are all kind of ways in which natural law imposes channels within which selection can take place, and some things can happen and other things don't happen. Plenty of things that go on in the biology in organisms aren't like this. So take the first step, meiosis. Why do cells split into spheres and not cubes? It's not random mutation and natural selection; it's a law of physics. There's no reason to think that laws of physics stop there, they work all the way through. Well, they constrain the biology, sure. Chomsky: Okay, well then it's not just random mutation and selection. It's random mutation, selection, and everything that matters, like laws of physics.

What I think is valuable is the history of science. I think we learn a lot of things from the history of science that can be very valuable to the emerging sciences. Particularly when we realize that in say, the emerging cognitive sciences, we really are in a kind of pre-Galilean stage. We don't know wh

at we're looking for anymore than Galileo did, and there's a lot to learn from that.

As compared to dogmatic atheists, non-dogmatic disbelievers go only one (modest) step beyond the undecided agnostic. It’s accurate to say that neither the non-dogmatic atheist nor the agnostic holds any faith in the existence of a god. But the more tolerant (or less “doctrinaire”) atheist—unlike the agnostic, who prefers to remain non-committal—is still ready to take a stand on the matter, asserting (though as an opinion): “I believe that no god (and certainly not God in the traditional sense)  exists.”

But even though they strive to keep an open mind on all things—for they’re oriented toward the world empirically and governed by facts rather than faith— non-dogmatic atheists simply can’t find any compelling evidence for a (monotheistic or biblical) god's existence.

To them, all that humans are able to know for sure exists in the realm of the relative. Anything beyond that points to the insoluble mysteries of the universe—which even today’s scientists recognize may be forever beyond their ever-more-precise instruments of knowing.

Coming full circle, if scientists in general—and physicists in particular—can’t ever be absolutely certain about Absolutes, how much more difficult must it be for metaphysicists to attain such certitude? To answer my own question: very difficult, indeed!

molecular biologists were soon speaking of information, not to mention codes, libraries, alphabets and transcription, without any sense of metaphor. In Gleick’s words, “Genes themselves are made of bits.” At the same time, physicists exploring what Einstein had called the “spooky” paradoxes of quantum mechanics began to see information as the substance from which everything else in the universe derives. As the physicist John Archibald Wheeler put it in a paper title, “It From Bit.”

"Modern physics is based on two theories, relativity and the quantum theory, so half of modern physics would have to be replaced by a new theory.

Pope Francis.” Once they consulted the blog post it advertised, though, they the tweet “deemed overtly speculative and not prescient.” 

But that doesn’t quite mean anything. The authors admit that the study might have failed for many reasons: Time travelers might not have the ability to physically adjust the past; they might not have posted about the events the authors were looking for; they might have posted about the events but not turned up in a search. Time travelers might have also read the study or this news story about it, and been sure to making avoid any careless mistakes.

[G]iven the current prevalence of the Internet, its numerous portals around the globe, and its numerous uses in communication, this search might be considered the most sensitive and comprehensive search yet for time travel from the future.