Saturday, June 22, 2013
There’s a Fly in My Tweets
Many important public health questions are difficult and costly to answer. What kind of risks do highly localized sources of pollution, like dry cleaners that use volatile chemicals, pose to the health of nearby residents? Are people with many friends healthier, or do those friendships increase the likelihood of infectious disease? Do frequent visits to public spaces like bars, gyms and restaurants affect a person’s health?
Researchers have been striving for generations to answer such questions, using health surveys of samples of individuals and computational studies of simulated populations. Now, however, the rise of social media and the burgeoning field of data science provide powerful tools to find high-precision, real-world answers with little cost or effort.
The millions of people posting to sites like Twitter and Facebook can be viewed as a vast organic sensor network, providing a real-time stream of data about the social, biological and physical worlds. While people use social media to build and maintain their social ties, the “data exhaust” of their postings can be analyzed to provide an enormous range of information at a population scale.
For example, my research group at the University of Rochester has analyzed Twitter postings from millions of cellphone users in New York City to develop a system to monitor food-poisoning outbreaks at restaurants.
We began by creating algorithms that can identify tweets about a given topic with near-perfect precision, even if the words and phrases used vary widely. The GPS information embedded in tweets sent from cellphones lets us integrate them with a variety of geographic databases.
We then feed the information into what we call the nEmesis system, whose development was led by our graduate student Adam Sadilek, now a researcher at Google. It begins by finding tweets that are sent from restaurants, which we can locate on Google Maps with 97 percent accuracy, thanks to GPS coordinates.
When a user is identified as having been at a restaurant, all of his or her tweets, from anywhere, are collected for the next 72 hours and analyzed to discover if any appear to report food poisoning symptoms, like vomiting, diarrhea, abdominal pain, fever or chills.
Such reports are rare but significant. Over a four-month period, our system collected 3.8 million tweets, from which we were able to trace 23,000 restaurant visitors and found 480 reports of likely food poisoning. Restaurants were then scored by the number of food poisoning reports from their patrons.
The Twitter reports are not an exact indicator — any individual case could well be caused by factors unrelated to the restaurant meal. But in aggregate the numbers are revealing. Working with Vincent Silenzio, who teaches in the department of community and preventive medicine at our medical school, we compared the results with the current database of restaurant inspections conducted by New York City’s Department of Health and Mental Hygiene. We found significant correlation between restaurants’ violation scores and the Twitter-based scores.
Our project isn’t alone. While an army of corporations are busy data mining social media for marketing, a small but growing number of research groups have initiated similar efforts to leverage the torrent of online information for social good.
Researchers have been striving for generations to answer such questions, using health surveys of samples of individuals and computational studies of simulated populations. Now, however, the rise of social media and the burgeoning field of data science provide powerful tools to find high-precision, real-world answers with little cost or effort.
The millions of people posting to sites like Twitter and Facebook can be viewed as a vast organic sensor network, providing a real-time stream of data about the social, biological and physical worlds. While people use social media to build and maintain their social ties, the “data exhaust” of their postings can be analyzed to provide an enormous range of information at a population scale.For example, my research group at the University of Rochester has analyzed Twitter postings from millions of cellphone users in New York City to develop a system to monitor food-poisoning outbreaks at restaurants.
We began by creating algorithms that can identify tweets about a given topic with near-perfect precision, even if the words and phrases used vary widely. The GPS information embedded in tweets sent from cellphones lets us integrate them with a variety of geographic databases.
We then feed the information into what we call the nEmesis system, whose development was led by our graduate student Adam Sadilek, now a researcher at Google. It begins by finding tweets that are sent from restaurants, which we can locate on Google Maps with 97 percent accuracy, thanks to GPS coordinates.
When a user is identified as having been at a restaurant, all of his or her tweets, from anywhere, are collected for the next 72 hours and analyzed to discover if any appear to report food poisoning symptoms, like vomiting, diarrhea, abdominal pain, fever or chills.
Such reports are rare but significant. Over a four-month period, our system collected 3.8 million tweets, from which we were able to trace 23,000 restaurant visitors and found 480 reports of likely food poisoning. Restaurants were then scored by the number of food poisoning reports from their patrons.
The Twitter reports are not an exact indicator — any individual case could well be caused by factors unrelated to the restaurant meal. But in aggregate the numbers are revealing. Working with Vincent Silenzio, who teaches in the department of community and preventive medicine at our medical school, we compared the results with the current database of restaurant inspections conducted by New York City’s Department of Health and Mental Hygiene. We found significant correlation between restaurants’ violation scores and the Twitter-based scores.
Our project isn’t alone. While an army of corporations are busy data mining social media for marketing, a small but growing number of research groups have initiated similar efforts to leverage the torrent of online information for social good.
by Henry Kautz, NY Times | Read more:
Image: Olimpia Zagnoli
Eva Cassidy
It's funny how the distance can make you feel close and the things you lost are the things you want most. The weather's fine here, perfect shade of blue, I guess that's why I've been thinking of you. So I call you up just to tell you why, why I left you and say goodbye. Ooh must be the mood I'm in, I'm thinking of you again, I call you up just to tell you why, why I left you and say goodbye.
I know you're different now and I guess I changed too, and I thought what was once so right was so wrong for you. Yesterday I was talking and I heard your name, the weather's fine here with a slight chance of rain. Time makes you sorry for the things that you've done, sometimes you walk away and sometimes you run.. and the weather's fine here, I can feel a slight chill, some things change babe and some never will. I call you up just to tell you why to say I love you and to say goodbye.
Friday, June 21, 2013
Are You with the Right Mate?
Elliott Katz was stunned to find himself in the middle of a divorce after two kids and 10 years of marriage. The Torontonian, a policy analyst for the Ottawa government, blamed his wife. "She just didn't appreciate all I was doing to make her happy." He fed the babies, and he changed their diapers. He gave them their baths, he read them stories, and put them to bed. Before he left for work in the morning, he made them breakfast. He bought a bigger house and took on the financial burden, working evenings to bring in enough money so his wife could stay home full-time.
He thought the solution to the discontent was for her to change. But once on his own, missing the daily interaction with his daughters, he couldn't avoid some reflection. "I didn't want to go through this again. I asked whether there was something I could have done differently. After all, you can wait years for someone else to change."
What he decided was, indeed, there were some things he could have done differently—like not tried as hard to be so noncontrolling that his wife felt he had abandoned decision-making entirely. His wife, he came to understand, felt frustrated, as if she were "a married single parent," making too many of the plans and putting out many of the fires of family life, no matter how many chores he assumed.
Ultimately, he stopped blaming his wife for their problems. "You can't change another person. You can only change yourself," he says. "Like lots of men today," he has since found, "I was very confused about my role as partner." After a few post-divorce years in the mating wilderness, Katz came to realize that framing a relationship in terms of the right or wrong mate is by itself a blind alley.
"We're given a binary model," says New York psychotherapist Ken Page. "Right or wrong. Settle or leave. We are not given the right tools to think about relationships. People need a better set of options."
Sooner or later, there comes a moment in all relationships when you lie in bed, roll over, look at the person next to you and think it's all a dreadful mistake, says Boston family therapist Terrence Real. It happens a few months to a few years in. "It's an open secret of American culture that disillusionment exists. I go around the country speaking about 'normal marital hatred.' Not one person has ever asked what I mean by that. It's extremely raw."
What to do when the initial attraction sours? "I call it the first day of your real marriage," Real says. It's not a sign that you've chosen the wrong partner. It is the signal to grow as an individual—to take responsibility for your own frustrations. Invariably, we yearn for perfection but are stuck with an imperfect human being. We all fall in love with people we think will deliver us from life's wounds but who wind up knowing how to rub against us.
A new view of relationships and their discontents is emerging. We alone are responsible for having the relationship we want. And to get it, we have to dig deep into ourselves while maintaining our connections. It typically takes a dose of bravery—what Page calls "enlightened audacity." Its brightest possibility exists, ironically, just when the passion seems most totally dead. If we fail to plumb ourselves and speak up for our deepest needs, which admittedly can be a scary prospect, life will never feel authentic, we will never see ourselves with any clarity, and everyone will always be the wrong partner.
by Rebecca Webber, Psychology Today | Read more:
Image:uncredited
Light Rail Fits In
Green tracks have become increasingly popular in Europe and can be seen in pretty much every major European cities from Barcelona to Frankfurt, Milan, St-Etienne and Strasbourg.
by Kaushik, Amusing Planet | Read more:
Image via:
Lawyers Eye NSA Data as Treasure Trove for Evidence
The National Security Agency has spent years demanding that companies turn over their data. Now, the spy agency finds the shoe is on the other foot. A defendant in a Florida murder trial says telephone records collected by the NSA as part of its surveillance programs hold evidence that would help prove his innocence, and his lawyer has demanded that prosecutors produce those records. On Wednesday, the federal government filed a motion saying it would refuse, citing national security. But experts say the novel legal argument could encourage other lawyers to fight for access to the newly disclosed NSA surveillance database.
"What's good for the goose is good for the gander, I guess," said George Washington University privacy law expert Dan Solove. "In a way, it's kind of ironic."
Defendant Terrance Brown is accused of participating in the 2010 murder of a Brinks security truck driver. Brown maintains his innocence, and claims cellphone location records would show he wasn't at the scene of the crime. Brown's cellphone provider — MetroPCS — couldn't produce those records during discovery because it had deleted the data already.
On seeing the story in the Guardian indicating that Verizon had been ordered to turn over millions of calling records to the NSA last month, Brown's lawyer had a novel idea: Make the NSA produce the records.
Brown's lawyer, Marshall Dore Louis, said he couldn't comment while the trial was ongoing.
"Relying on a June 5, 2013, Guardian newspaper article ... Defendant Brown now suggests that the Government likely actually does possess the metadata relating to telephone calls made in July 2010 from the two numbers attributed to Defendant Brown," wrote U.S. District Judge Robin Rosenbaum in an order demanding that the federal government respond to the request on June 10.
The laws of evidence require that prosecutors turn over to the defense any records they have that might help prove a suspect's innocence.
"This opens up a Pandora's box," said Mark Rasch, former head of the Department of Justice Computer Crimes Unit, and now an independent consultant. “You will have situations where the phone companies no longer have the data, but the government does, and lawyers will try to get that data.” (...)
It's all part of the hazard of becoming, effectively, a backup server for all the nation's technology companies, said Solove.
"What's good for the goose is good for the gander, I guess," said George Washington University privacy law expert Dan Solove. "In a way, it's kind of ironic."Defendant Terrance Brown is accused of participating in the 2010 murder of a Brinks security truck driver. Brown maintains his innocence, and claims cellphone location records would show he wasn't at the scene of the crime. Brown's cellphone provider — MetroPCS — couldn't produce those records during discovery because it had deleted the data already.
On seeing the story in the Guardian indicating that Verizon had been ordered to turn over millions of calling records to the NSA last month, Brown's lawyer had a novel idea: Make the NSA produce the records.
Brown's lawyer, Marshall Dore Louis, said he couldn't comment while the trial was ongoing.
"Relying on a June 5, 2013, Guardian newspaper article ... Defendant Brown now suggests that the Government likely actually does possess the metadata relating to telephone calls made in July 2010 from the two numbers attributed to Defendant Brown," wrote U.S. District Judge Robin Rosenbaum in an order demanding that the federal government respond to the request on June 10.
The laws of evidence require that prosecutors turn over to the defense any records they have that might help prove a suspect's innocence.
"This opens up a Pandora's box," said Mark Rasch, former head of the Department of Justice Computer Crimes Unit, and now an independent consultant. “You will have situations where the phone companies no longer have the data, but the government does, and lawyers will try to get that data.” (...)
It's all part of the hazard of becoming, effectively, a backup server for all the nation's technology companies, said Solove.
by Bob Sullivan, NBC News | Read more:
Image: NSA
Is Franz Kafka Overrated?
Edmund Wilson claimed that the only book he could not read while eating his breakfast was by the Marquis de Sade. I, for different reasons, have been having a difficult time reading Franz Kafka with my morning tea and toast. So much torture, description of wounds, disorientation, sadomasochism, unexplained cruelty, appearance of rodents, beetles, vultures, and other grotesque creatures—all set out against a background of utter hopelessness. Distinctly not a jolly way to start the day. Kafka doesn’t make for very comforting reading at bedtime, either.Hypochondriac, insomniac, food faddist, cripplingly indecisive, terrified by life, obsessed with death, Franz Kafka turned, as best he was able, his neuroses into art. As a character in Isaac Bashevis Singer’s story “A Friend of Kafka” says, Kafka was “Homo sapiens in his highest degree of self-torture.” Still, the consensus remains that Franz Kafka is a modern master—a master, more specifically, in the modernist tradition, housed in the same pantheon as Joyce, Picasso, Stravinsky, Mallarmé, and other artists who have radically altered contemporary understanding of the world.
Kafka created “obscure lucidity,” Erich Heller wrote in his book on Kafka. “His is an art more poignantly and disturbingly obscure,” he added, “than literature has ever known.” One thinks one grasps Kafka’s meaning, but does one, really? All seems so clear, yet is it, truly? A famous aphorism of Kafka’s reads: “Hiding places there are innumerable, escape is only one, but possibilities of escape, again, are as many as hiding places.” Another runs: “A cage went in search of a bird.”
As with Kafka’s aphorisms, so with his brief parables. The parables, Walter Benjamin wrote, are “never exhausted by what is explainable; on the contrary, he took all conceivable precautions against the interpretation of his writings.” Whatever these precautions may have been, they were inadequate, for the works of Franz Kafka—apart perhaps only from the Bible and the works of Shakespeare—may be the most relentlessly interpreted, if not overinterpreted, in the modern world. (...)
Kafka, the critic Jeremy Adler holds, is “less dazzling than Proust, less innovative than Joyce, [but his] vision is more stark, more painful, more obviously universal than that of his peers.” Kafka’s universality derives from his high level of generality. Places are not named; most characters go undescribed; landscapes, sere and menacing, appear as they might in nightmares. Joyce and Proust work from detail to generality; Kafka works from generality to detail, giving his fiction the feeling that something deeply significant is going on, if only we could grasp what precisely it is.
“The vicinity of literature and autobiography could hardly be closer than it is with Kafka,” Erich Heller wrote. “Indeed, it almost amounts to identity.” The broader lineaments of Kafka’s autobiography are well known. Taken together, they constitute a life of nearly unrelieved doubt and mental suffering. (...)
Benjamin, Begley, Heller, Friedländer, and other critics who take Kafka’s greatness as self-evident agree that Kafka cannot be either explained or judged in the same way as other literary artists. Benjamin believed that “Kafka’s entire work constitutes a code of gestures which surely had no definite symbolic meaning for the author from the outset; rather, the author tried to derive such a meaning from them in ever-changing contexts and experimental groupings.”
Kafka felt that his talent was “for portraying my dream-like inner life.” But dreams, however gripping, are aesthetically unsatisfying.
“In Kafka’s fiction,” Friedländer writes, “the Truth remains inaccessible and is possibly nonexistent.” Begley, remarking on an object referred to as “Odradek” in a five-paragraph exercise of Kafka’s called “The Cares of a Family Man,” writes: “Some things cannot be explained.” Of “The Metamorphosis,” Kafka’s most famous story, Heller writes: “It defies any established intellectual order and familiar form of understanding, and thus arouses the kind of intellectual anxiety that greedily and compulsively reaches out for interpretations.” In his Times Literary Supplement review, Josipovici, noting that 100 years have passed since Kafka wrote his story “The Judgment,” adds: “We are probably no nearer to understanding that or any other of his works today than his first readers were, nor should we expect to be.”
Kafka, in other words, is given a pass on criticism. The argument is that he cannot finally be explained, but merely read, appreciated, and reread until his meaning, somehow, washes over you. But what if this meaning seems oddly skewed and in our day even outmoded, in the way great literature never is?
“In Kafka’s fiction,” Friedländer writes, “the Truth remains inaccessible and is possibly nonexistent.” Begley, remarking on an object referred to as “Odradek” in a five-paragraph exercise of Kafka’s called “The Cares of a Family Man,” writes: “Some things cannot be explained.” Of “The Metamorphosis,” Kafka’s most famous story, Heller writes: “It defies any established intellectual order and familiar form of understanding, and thus arouses the kind of intellectual anxiety that greedily and compulsively reaches out for interpretations.” In his Times Literary Supplement review, Josipovici, noting that 100 years have passed since Kafka wrote his story “The Judgment,” adds: “We are probably no nearer to understanding that or any other of his works today than his first readers were, nor should we expect to be.”
Kafka, in other words, is given a pass on criticism. The argument is that he cannot finally be explained, but merely read, appreciated, and reread until his meaning, somehow, washes over you. But what if this meaning seems oddly skewed and in our day even outmoded, in the way great literature never is?
by Joseph Epstein, The Atlantic | Read more:
Image: MVM
Sea of Bikes Swamps Amsterdam
About 6:30 weekday mornings, throngs of bicycles, with a smattering of motor scooters and pedestrians, pour off the ferries that carry bikers and other passengers free of charge across the IJ (pronounced “eye”) harbor, clogging the streets and causing traffic jams down behind Amsterdam’s main train station.
“In the afternoon it’s even more,” moaned Erwin Schoof, a metalworker in his 20s who lives in the canal-laced center of town and battles the chaos daily to cross to his job.
Willem van Heijningen, a railway official responsible for bikes around the station, said, “It’s not a war zone, but it’s the next thing to it.”
This clogged stream of cyclists is just one of many in a city as renowned for bikes as Los Angeles is for automobiles or Venice for gondolas. Cyclists young and old pedal through narrow lanes and along canals. Mothers and fathers balance toddlers in spacious wooden boxes affixed to their bikes, ferrying them to school or day care. Carpenters carry tools and supplies in similar contraptions and electricians their cables. Few wear helmets. Increasingly, some are saying what was simply unthinkable just a few years ago: There are too many bikes.
While cities like New York struggle to get people onto bikes, Amsterdam is trying to keep its hordes of bikes under control. In a city of 800,000, there are 880,000 bicycles, the government estimates, four times the number of cars. In the past two decades, travel by bike has grown by 40 percent so that now about 32 percent of all trips within the city are by bike, compared with 22 percent by car.
Applauding this accomplishment, a Danish urban planning consultancy, Copenhagenize Design, which publishes an annual list of the 20 most bike-friendly cities, placed Amsterdam in first place this year, as it has frequently in the past. (The list consists mostly of European cities, though Tokyo; Nagoya, Japan; and Rio de Janeiro made the cut. Montreal is the only North American city included.)
But many Amsterdamers say it is not so much the traffic jams like those at the morning ferry that annoy them most, but the problem of where to park their bikes once they get to where they’re going, in a city with almost more water than paved surfaces.
“Just look at this place!” said Xem Smit, 22, who for the past year has struggled to maintain order at a municipal bike parking lot in the heart of town, waving a hand at bikes chained to lampposts, benches, trees and almost any other permanent object across a tree-lined square between the stock market and the big De Bijenkorf department store.
by John Tagliabue, NY Times | Read more:
Image: Pavel Prokopchik for The New York Times
“In the afternoon it’s even more,” moaned Erwin Schoof, a metalworker in his 20s who lives in the canal-laced center of town and battles the chaos daily to cross to his job.Willem van Heijningen, a railway official responsible for bikes around the station, said, “It’s not a war zone, but it’s the next thing to it.”
This clogged stream of cyclists is just one of many in a city as renowned for bikes as Los Angeles is for automobiles or Venice for gondolas. Cyclists young and old pedal through narrow lanes and along canals. Mothers and fathers balance toddlers in spacious wooden boxes affixed to their bikes, ferrying them to school or day care. Carpenters carry tools and supplies in similar contraptions and electricians their cables. Few wear helmets. Increasingly, some are saying what was simply unthinkable just a few years ago: There are too many bikes.
While cities like New York struggle to get people onto bikes, Amsterdam is trying to keep its hordes of bikes under control. In a city of 800,000, there are 880,000 bicycles, the government estimates, four times the number of cars. In the past two decades, travel by bike has grown by 40 percent so that now about 32 percent of all trips within the city are by bike, compared with 22 percent by car.
Applauding this accomplishment, a Danish urban planning consultancy, Copenhagenize Design, which publishes an annual list of the 20 most bike-friendly cities, placed Amsterdam in first place this year, as it has frequently in the past. (The list consists mostly of European cities, though Tokyo; Nagoya, Japan; and Rio de Janeiro made the cut. Montreal is the only North American city included.)
But many Amsterdamers say it is not so much the traffic jams like those at the morning ferry that annoy them most, but the problem of where to park their bikes once they get to where they’re going, in a city with almost more water than paved surfaces.
“Just look at this place!” said Xem Smit, 22, who for the past year has struggled to maintain order at a municipal bike parking lot in the heart of town, waving a hand at bikes chained to lampposts, benches, trees and almost any other permanent object across a tree-lined square between the stock market and the big De Bijenkorf department store.
Image: Pavel Prokopchik for The New York Times
On Friendship
[ed. I like the term "carbonation" in reference to a certain type of friend. I share that inclination.]
“He has lots of friends,” we’ll mention in recommending somebody, whether a plumber or a stockbroker: he’s okay, he’ll lend an ear, he won’t leave a customer in the lurch. Lending an ear is essential in mainline friendships, and less disruptive than lending money. “I’m always here for you” is the desired pledge (like the colloquial promise “I have your back”) of best-friendship, a category often lasting at least until marriage, if not beyond. The personalities that occupy the niche—nerd or happy-go-lucky—might change according to the phases of life, but draw a nostalgic smile in our mind’s eye when we remember them. (...)
“How are you?” is the current universal greeting in America, yet not to answer “Fine” would violate the social compact in a minor way because almost nobody who asks wants to know if you’re not. If you can’t keep your marbles together, agencies exist to do it for you. Friends are for when the question isn’t rote, however, and the “Me, myself, and I” of childhood fame feels buffaloed. You and the cat are watching a hummingbird feeder out the window; yet you need more to get up and fight the day. Call a fellow vinyl collector, card player, Little League coach. Yes, the specialist told us on the spectrum of autism it’s a milder kind. … So he sez it was only a one-night stand; he didn’t expect me to cry. … My skills are dated or outdated, whichever term they used. … I was so happy for a second, I couldn’t speak, didn’t try, but then he died. … I wonder if 40 is too late to apply for the ministry? Is it silly to inquire? … The school apologized for letting him go home on the bus. They didn’t realize it was a concussion. … A friend pauses to listen, his grin of solace not a tic. (...)
In adulthood, friendships originate adventitiously: at the water cooler or neighborhood association. My closest in old age began when a pizza counterman made fun of my stutter and I returned out of curiosity to see why he would. It turned out that he needed affection so badly, he felt compelled to outrage strangers to test their loyalty; after testing mine, he became wonderfully generous, recounting dozens of typewriter-ready stories I could make use of, from war lore to which of the ladies in the Laundromat had turned tricks (he said) in her youth.
He protected my house from robbery or vandalism during hunting season, while mending relations with his children, estranged to various degrees, rehearsing with me his explanations to them beforehand. His fireman father had thrown his mother down the cellar stairs, so although he was Irish, a local Jersey mafia don adopted him as a mascot for landscaping or driving hijacked trucks from Point A to Point B. His mother, when he was small, used to take him to a Catholic cemetery to pee on the graves of the nuns who’d mistreated her at their orphanage, slamming her fingers in a door, and so forth—another memory his combat stint in Korea didn’t soften. In reparative interludes we made friends—the verb is kinetic—till the pistol he carried no longer tempted him toward Russian roulette. But he still drove customers away if he could, skinning the raccoons and coyotes he trapped on the sandwich board at his greasy spoon, so that if people wandered in asking for a pastrami hero, John could point at the naked carcass he was cutting at: “Pick your part!” It decreased sales. (...)
I like carbonation in my friends: out-on-a-limb idealism or a traveler’s itch, a shivery past or libertarian streak, with frostbite scars, perhaps, or a veteran’s fatalistic flinch when a car backfires. The “vibes” people speak of seem natural to me. When you intuit that somebody you hadn’t expected is approaching before they reach your door, or realize that a person, silent, elsewhere in the house, needs a hug, it’s not “extrasensory perception” but telepathy to antennae we haven’t pinpointed, a force field we haven’t quantified, which also warns us, when we’re hurrying down a city street, about unseen dangers around the corner: potential collisions, muggers, flimflammers, whatever.
by Edward Hoagland, The American Scholar | Read more:
Photo by Maureen Lunn
Physics’s Pangolin
Theoretical physics is beset by a paradox that remains as mysterious today as it was a century ago: at the subatomic level things are simultaneously particles and waves. Like the duck-rabbit illusion first described in 1899 by the Polish-born American psychologist Joseph Jastrow, subatomic reality appears to us as two different categories of being.
But there is another paradox in play. Physics itself is riven by the competing frameworks of quantum theory and general relativity, whose differing descriptions of our world eerily mirror the wave-particle tension. When it comes to the very big and the extremely small, physical reality appears to be not one thing, but two. Where quantum theory describes the subatomic realm as a domain of individual quanta, all jitterbug and jumps, general relativity depicts happenings on the cosmological scale as a stately waltz of smooth flowing space-time. General relativity is like Strauss — deep, dignified and graceful. Quantum theory, like jazz, is disconnected, syncopated, and dazzlingly modern.
Physicists are deeply aware of the schizophrenic nature of their science and long to find a synthesis, or unification. Such is the goal of a so-called ‘theory of everything’. However, to non-physicists, these competing lines of thought, and the paradoxes they entrain, can seem not just bewildering but absurd. In my experience as a science writer, no other scientific discipline elicits such contradictory responses. (...)
Many physicists are Platonists, at least when they talk to outsiders about their field. They believe that the mathematical relationships they discover in the world about us represent some kind of transcendent truth existing independently from, and perhaps a priori to, the physical world. In this way of seeing, the universe came into being according to a mathematical plan, what the British physicist Paul Davies has called ‘a cosmic blueprint’. Discovering this ‘plan’ is a goal for many theoretical physicists and the schism in the foundation of their framework is thus intensely frustrating. It’s as if the cosmic architect has designed a fiendish puzzle in which two apparently incompatible parts must be fitted together. Both are necessary, for both theories make predictions that have been verified to a dozen or so decimal places, and it is on the basis of these theories that we have built such marvels as microchips, lasers, and GPS satellites.
Quite apart from the physical tensions that exist between them, relativity and quantum theory each pose philosophical problems. Are space and time fundamental qualities of the universe, as general relativity suggests, or are they byproducts of something even more basic, something that might arise from a quantum process? Looking at quantum mechanics, huge debates swirl around the simplest situations. Does the universe split into multiple copies of itself every time an electron changes orbit in an atom, or every time a photon of light passes through a slit? Some say yes, others say absolutely not.
Theoretical physicists can’t even agree on what the celebrated waves of quantum theory mean. What is doing the ‘waving’? Are the waves physically real, or are they just mathematical representations of probability distributions? Are the ‘particles’ guided by the ‘waves’? And, if so, how? The dilemma posed by wave-particle duality is the tip of an epistemological iceberg on which many ships have been broken and wrecked.
Undeterred, some theoretical physicists are resorting to increasingly bold measures in their attempts to resolve these dilemmas. Take the ‘many-worlds’ interpretation of quantum theory, which proposes that every time a subatomic action takes place the universe splits into multiple, slightly different, copies of itself, with each new ‘world’ representing one of the possible outcomes.
When this idea was first proposed in 1957 by the American physicist Hugh Everett, it was considered an almost lunatic-fringe position. Even 20 years later, when I was a physics student, many of my professors thought it was a kind of madness to go down this path. Yet in recent years the many-worlds position has become mainstream. The idea of a quasi-infinite, ever-proliferating array of universes has been given further credence as a result of being taken up by string theorists, who argue that every mathematically possible version of the string theory equations corresponds to an actually existing universe, and estimate that there are 10 to the power of 500 different possibilities. To put this in perspective: physicists believe that in our universe there are approximately 10 to the power of 80 subatomic particles. In string cosmology, the totality of existing universes exceeds the number of particles in our universe by more than 400 orders of magnitude.
Nothing in our experience compares to this unimaginably vast number. Every universe that can be mathematically imagined within the string parameters — including ones in which you exist with a prehensile tail, to use an example given by the American string theorist Brian Greene — is said to be manifest somewhere in a vast supra-spatial array ‘beyond’ the space-time bubble of our own universe.
What is so epistemologically daring here is that the equations are taken to be the fundamental reality. The fact that the mathematics allows for gazillions of variations is seen to be evidence for gazillions of actual worlds.
This kind of reification of equations is precisely what strikes some humanities scholars as childishly naive. At the very least, it raises serious questions about the relationship between our mathematical models of reality, and reality itself.
by Margaret Wertheim, Aeon | Read more:
Illustration by Claire Scully
But there is another paradox in play. Physics itself is riven by the competing frameworks of quantum theory and general relativity, whose differing descriptions of our world eerily mirror the wave-particle tension. When it comes to the very big and the extremely small, physical reality appears to be not one thing, but two. Where quantum theory describes the subatomic realm as a domain of individual quanta, all jitterbug and jumps, general relativity depicts happenings on the cosmological scale as a stately waltz of smooth flowing space-time. General relativity is like Strauss — deep, dignified and graceful. Quantum theory, like jazz, is disconnected, syncopated, and dazzlingly modern.Physicists are deeply aware of the schizophrenic nature of their science and long to find a synthesis, or unification. Such is the goal of a so-called ‘theory of everything’. However, to non-physicists, these competing lines of thought, and the paradoxes they entrain, can seem not just bewildering but absurd. In my experience as a science writer, no other scientific discipline elicits such contradictory responses. (...)
Many physicists are Platonists, at least when they talk to outsiders about their field. They believe that the mathematical relationships they discover in the world about us represent some kind of transcendent truth existing independently from, and perhaps a priori to, the physical world. In this way of seeing, the universe came into being according to a mathematical plan, what the British physicist Paul Davies has called ‘a cosmic blueprint’. Discovering this ‘plan’ is a goal for many theoretical physicists and the schism in the foundation of their framework is thus intensely frustrating. It’s as if the cosmic architect has designed a fiendish puzzle in which two apparently incompatible parts must be fitted together. Both are necessary, for both theories make predictions that have been verified to a dozen or so decimal places, and it is on the basis of these theories that we have built such marvels as microchips, lasers, and GPS satellites.
Quite apart from the physical tensions that exist between them, relativity and quantum theory each pose philosophical problems. Are space and time fundamental qualities of the universe, as general relativity suggests, or are they byproducts of something even more basic, something that might arise from a quantum process? Looking at quantum mechanics, huge debates swirl around the simplest situations. Does the universe split into multiple copies of itself every time an electron changes orbit in an atom, or every time a photon of light passes through a slit? Some say yes, others say absolutely not.
Theoretical physicists can’t even agree on what the celebrated waves of quantum theory mean. What is doing the ‘waving’? Are the waves physically real, or are they just mathematical representations of probability distributions? Are the ‘particles’ guided by the ‘waves’? And, if so, how? The dilemma posed by wave-particle duality is the tip of an epistemological iceberg on which many ships have been broken and wrecked.
Undeterred, some theoretical physicists are resorting to increasingly bold measures in their attempts to resolve these dilemmas. Take the ‘many-worlds’ interpretation of quantum theory, which proposes that every time a subatomic action takes place the universe splits into multiple, slightly different, copies of itself, with each new ‘world’ representing one of the possible outcomes.
When this idea was first proposed in 1957 by the American physicist Hugh Everett, it was considered an almost lunatic-fringe position. Even 20 years later, when I was a physics student, many of my professors thought it was a kind of madness to go down this path. Yet in recent years the many-worlds position has become mainstream. The idea of a quasi-infinite, ever-proliferating array of universes has been given further credence as a result of being taken up by string theorists, who argue that every mathematically possible version of the string theory equations corresponds to an actually existing universe, and estimate that there are 10 to the power of 500 different possibilities. To put this in perspective: physicists believe that in our universe there are approximately 10 to the power of 80 subatomic particles. In string cosmology, the totality of existing universes exceeds the number of particles in our universe by more than 400 orders of magnitude.
Nothing in our experience compares to this unimaginably vast number. Every universe that can be mathematically imagined within the string parameters — including ones in which you exist with a prehensile tail, to use an example given by the American string theorist Brian Greene — is said to be manifest somewhere in a vast supra-spatial array ‘beyond’ the space-time bubble of our own universe.
What is so epistemologically daring here is that the equations are taken to be the fundamental reality. The fact that the mathematics allows for gazillions of variations is seen to be evidence for gazillions of actual worlds.
This kind of reification of equations is precisely what strikes some humanities scholars as childishly naive. At the very least, it raises serious questions about the relationship between our mathematical models of reality, and reality itself.
by Margaret Wertheim, Aeon | Read more:
Illustration by Claire Scully
Thursday, June 20, 2013
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