Monthly Archives: August 2014

Time Travel Simulation Resolves “Grandfather Paradox”

Time Travel Simulation Resolves “Grandfather Paradox”

By Lee Billings

What would happen to you if you went back in time and killed your grandfather? A model using photons reveals that quantum mechanics can solve the quandary—and even foil quantum cryptography

On June 28, 2009, the world-famous physicist Stephen Hawking threw a party at the University of Cambridge, complete with balloons, hors d’oeuvres and iced champagne. Everyone was invited but no one showed up. Hawking had expected as much, because he only sent out invitations after his party had concluded. It was, he said, “a welcome reception for future time travelers,” a tongue-in-cheek experiment to reinforce his 1992 conjecture that travel into the past is effectively impossible.

But Hawking may be on the wrong side of history. Recent experiments offer tentative support for time travel’s feasibility—at least from a mathematical perspective. The study cuts to the core of our understanding of the universe, and the resolution of the possibility of time travel, far from being a topic worthy only of science fiction, would have profound implications for fundamental physics as well as for practical applications such as quantum cryptography and computing.

Closed timelike curves

The source of time travel speculation lies in the fact that our best physical theories seem to contain no prohibitions on traveling backward through time. The feat should be possible based on Einstein’s theory of general relativity, which describes gravity as the warping of spacetime by energy and matter. An extremely powerful gravitational field, such as that produced by a spinning black hole, could in principle profoundly warp the fabric of existence so that spacetime bends back on itself. This would create a “closed timelike curve,” or CTC, a loop that could be traversed to travel back in time.

Hawking and many other physicists find CTCs abhorrent, because any macroscopic object traveling through one would inevitably create paradoxes where cause and effect break down. In a model proposed by the theorist David Deutsch in 1991, however, the paradoxes created by CTCs could be avoided at the quantum scale because of the behavior of fundamental particles, which follow only the fuzzy rules of probability rather than strict determinism. “It’s intriguing that you’ve got general relativity predicting these paradoxes, but then you consider them in quantum mechanical terms and the paradoxes go away,” says University of Queensland physicist Tim Ralph. “It makes you wonder whether this is important in terms of formulating a theory that unifies general relativity with quantum mechanics.”

Experimenting with a curve

Recently Ralph and his PhD student Martin Ringbauer led a team that experimentally simulated Deutsch’s model of CTCs for the very first time, testing and confirming many aspects of the two-decades-old theory. Their findings are published in Nature Communications. Much of their simulation revolved around investigating how Deutsch’s model deals with the “grandfather paradox,” a hypothetical scenario in which someone uses a CTC to travel back through time to murder her own grandfather, thus preventing her own later birth. (Scientific American is part of Nature Publishing Group.)

Deutsch’s quantum solution to the grandfather paradox works something like this:

Instead of a human being traversing a CTC to kill her ancestor, imagine that a fundamental particle goes back in time to flip a switch on the particle-generating machine that created it. If the particle flips the switch, the machine emits a particle—the particle—back into the CTC; if the switch isn’t flipped, the machine emits nothing. In this scenario there is no a priori deterministic certainty to the particle’s emission, only a distribution of probabilities. Deutsch’s insight was to postulate self-consistency in the quantum realm, to insist that any particle entering one end of a CTC must emerge at the other end with identical properties. Therefore, a particle emitted by the machine with a probability of one half would enter the CTC and come out the other end to flip the switch with a probability of one half, imbuing itself at birth with a probability of one half of going back to flip the switch. If the particle were a person, she would be born with a one-half probability of killing her grandfather, giving her grandfather a one-half probability of escaping death at her hands—good enough in probabilistic terms to close the causative loop and escape the paradox. Strange though it may be, this solution is in keeping with the known laws of quantum mechanics.

In their new simulation Ralph, Ringbauer and their colleagues studied Deutsch’s model using interactions between pairs of polarized photons within a quantum system that they argue is mathematically equivalent to a single photon traversing a CTC. “We encode their polarization so that the second one acts as kind of a past incarnation of the first,” Ringbauer says. So instead of sending a person through a time loop, they created a stunt double of the person and ran him through a time-loop simulator to see if the doppelganger emerging from a CTC exactly resembled the original person as he was in that moment in the past.

By measuring the polarization states of the second photon after its interaction with the first, across multiple trials the team successfully demonstrated Deutsch’s self-consistency in action. “The state we got at our output, the second photon at the simulated exit of the CTC, was the same as that of our input, the first encoded photon at the CTC entrance,” Ralph says. “Of course, we’re not really sending anything back in time but [the simulation] allows us to study weird evolutions normally not allowed in quantum mechanics.”

Those “weird evolutions” enabled by a CTC, Ringbauer notes, would have remarkable practical applications, such as breaking quantum-based cryptography through the cloning of the quantum states of fundamental particles. “If you can clone quantum states,” he says, “you can violate the Heisenberg uncertainty principle,” which comes in handy in quantum cryptography because the principle forbids simultaneously accurate measurements of certain kinds of paired variables, such as position and momentum. “But if you clone that system, you can measure one quantity in the first and the other quantity in the second, allowing you to decrypt an encoded message.”

“In the presence of CTCs, quantum mechanics allows one to perform very powerful information-processing tasks, much more than we believe classical or even normal quantum computers could do,” says Todd Brun, a physicist at the University of Southern California who was not involved with the team’s experiment. “If the Deutsch model is correct, then this experiment faithfully simulates what could be done with an actual CTC. But this experiment cannot test the Deutsch model itself; that could only be done with access to an actual CTC.”

Alternative reasoning
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Deutsch’s model isn’t the only one around, however. In 2009 Seth Lloyd, a theorist at Massachusetts Institute of Technology, proposed an alternative, less radical model of CTCs that resolves the grandfather paradox using quantum teleportation and a technique called post-selection, rather than Deutsch’s quantum self-consistency. With Canadian collaborators, Lloyd went on to perform successful laboratory simulations of his model in 2011. “Deutsch’s theory has a weird effect of destroying correlations,” Lloyd says. “That is, a time traveler who emerges from a Deutschian CTC enters a universe that has nothing to do with the one she exited in the future. By contrast, post-selected CTCs preserve correlations, so that the time traveler returns to the same universe that she remembers in the past.”

This property of Lloyd’s model would make CTCs much less powerful for information processing, although still far superior to what computers could achieve in typical regions of spacetime. “The classes of problems our CTCs could help solve are roughly equivalent to finding needles in haystacks,” Lloyd says. “But a computer in a Deutschian CTC could solve why haystacks exist in the first place.”

Lloyd, though, readily admits the speculative nature of CTCs. “I have no idea which model is really right. Probably both of them are wrong,” he says. Of course, he adds, the other possibility is that Hawking is correct, “that CTCs simply don’t and cannot exist.” Time-travel party planners should save the champagne for themselves—their hoped-for future guests seem unlikely to arrive.

 

Monkey leaders and followers have ‘specialized brains’

Monkey leaders and followers have ‘specialized brains’macaques

Monkeys at the top and bottom of the social pecking
order have physically different brains, research has found.

A particular network of brain areas was bigger in dominant animals, while other regions were bigger in subordinates.

The study suggests that primate brains, including ours, can be specialized for life at either end of the hierarchy.

The differences might reflect inherited tendencies toward leading or following, or the brain adapting to an animal’s role in life – or a little of both.

Neuroscientists made the discovery, which appears in the journal Plos Biology, by comparing brain scans from 25 macaque monkeys that were already “on file” as part of ongoing research at the University of Oxford.

“We were also looking at learning and memory and decision-making, and the changes that are going on in your brain when you’re doing those things,” explained Dr MaryAnn Noonan, the study’s first author.

The decision to look at the animals’ social status produced an unexpectedly clear result, Dr Noonan said.

“It was surprising. All our monkeys were of different ages and different genders – but with fMRI (functional magnetic resonance imaging) you can control for all of that. And we were consistently seeing these same networks coming out.”

The monkeys live in groups of up to five, so the team identified their social status by watching their behaviour, then compared it to different aspects of the brain data.

In monkeys at the top of their social group, three particular bits of the brain tended to be larger (specifically the amygdala, the hypothalamus and the raphe nucleus). In subordinate monkeys, the tendency was for a different cluster of regions to be bigger (all within the striatum).

Nature plus nurture

At either end of the social ladder, compared to monkeys in the middle, the activity in all these different brain regions was more synchronized. The researchers believe these areas together constitute brain circuits that are crucial for negotiating social situations – interpreting social and emotional cues, learning the value of certain actions, and so on.

Dr Noonan said it was particularly interesting to see different brain regions expanded at the top and the bottom of the social ladder, indicating that dominance isn’t simply about being physically stronger and having an altogether bigger brain.

“It suggests that at either end [of the hierarchy], you really need a specific set of skills to be successful, and those skills are making higher neural demands on those areas of the brain,” she told the BBC.

“In the animal kingdom, you might think that being dominant is all about aggression – I’m the bigger monkey, bugger off the rest of you.

“But all of this put together means that dominance might actually depend not only on aggression and physical strength, but also on forming bonds and making coalitions – and being quite smart about placing your loyalties.”

The results cannot distinguish whether the differences in these monkeys’ brains were there from birth, predisposing them to a particular social lot in life, or whether they reflect ongoing changes in the brain’s organization based on the demands of living with a particular status. Dr Noonan thinks that a combination of both these effects is the most likely explanation.

“It probably is both, because they’re both really important mechanisms to have on board. You can imagine if you’ve come from ‘good stock’ within the monkey world, and your dad was really strong and muscly, you’ll inherit those genes, and that might set your brain up in a certain way.

“But of course you’re going to have to be plastic, in order to succeed and survive. You’ll have to be adapting your behavior and therefore your brain has got to adapt too.”

macaques

Differences between dominant and subordinate monkeys
could be adaptive or inherited, or a mixture of both

There is no reason to suspect that the correlations identified in the study would not apply to other primates, like apes and humans.

“The regions that we’ve found are all there in humans and they all do similar things,” Dr Noonan said.

But in our society, social position can vary considerably in different situations – so it is might be difficult to define “dominance” for a human study.

“While we might be top-dog in one circle of friends, at work we might be more of a social climber. The fluidity of our social position and how our brains adapt our behavior to succeed in each context is the next exciting direction for this area of research.”

The Star Wars George Lucas Doesn’t Want You To See

The Star Wars George Lucas Doesn’t Want You To See

By Rose Eveleth

 
The original 1977 version of the saga is nearly
impossible to find, so these fans made their own.

In 1978, Star Wars won seven Academy Awards. But if you want to watch that original version, the first of George Lucas’s soon to be seven-part saga, you’ll find it difficult. In fact, it’s actually impossible to buy an official copy of Star Wars as it was first released. Lucas doesn’t want you to see that version. Instead, he wants you to watch the continuously updated special editions—movies with added CGI, changed sound effects, and whole new scenes.

According to some fans, every element that prompted the Academy to recognize the original Star Wars has been changed in these new versions. And some of those fans are now taking it upon themselves to recreate the original Star Wars in a process they call “despecializing.” They gather in online forums and share their work—painstakingly reassembling the movie from a handful of different versions of the film, from VHS to DVD to 35mm print scans using photography and animation software.

One of the most well known despecializers goes by the name “Harmy,” and he recently released a little behind-the-scenes look at the various sources he used for his despecialized edition.

People like Harmy who create despecialized versions of Star Wars go through and correct all kinds of additions and changes that the later special editions added. In the original versions of the films, for example, it’s clear that Han Solo pulled out his gun and shot the bounty hunter Greedo. In the 1997 version, Greedo shoots first. In the 2004 version, they shoot at the same time. With the release of the later films, later versions of the original trilogy were edited to add in appearances from Jar Jar Binks and Hayden Christensen. Lucas even replaced the voice of Jason Wingreen*—the original Boba Fett—with the voice of Temuera Morrison who played Jango Fett in Episode II: Attack of the Clones.

There are huge lists of these inconsistencies online at places like SaveStarWars.com and OriginalTrilogy.com, where fans dissect the films and point out discrepancies. And on these message boards, Harmy is a bit of a superhero—although in many ways an unlikely one.

Harmy—a 25-year-old from the Czech Republic—never saw the original Star Wars in theaters. Instead, he had a VHS tape that he watched as a kid. And when he first saw the special editions, he actually liked them. But as his Star Wars fandom grew—he did his undergraduate thesis on the cultural impact of the original movies—so did his desire to see the film in its earliest state. Using skills he picked up in college, he created his first despecialized version four years ago. Now, he’s on version 2.5, and between new copies of the movie being made available, and the techniques he’s learned along the way, he’s confident this version is the best one yet. “I’m pretty proud of these latest ones,” he told me.

For Harmy, the project is all about being able to show people who haven’t seen the original Star Wars what the film was like when it first became a phenomenon. “Look at this awesome film that was made in the ’70s,” he says, “I want to show that to people. I wanted to show my brother. He was three when I started working and I showed it to him when he was five and he loved it.”

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It’s not that fans want to ban the new versions of Star Wars—no matter how much they may dislike them. They simply want to have a choice. Harmy even admits that he might watch the special edition every now and then. “If both versions were available in the same quality I would probably enjoy watching the special edition once in a while. It’s not about George Lucas not being able to do these special editions. If people like the special editing, they can continue watching those. As long as both versions are available.”

For his part, George Lucas doesn’t really care what Harmy and his cohort want. In 2004, when a new DVD special edition came out, Lucas told the Associated Press he had little sympathy for fans who yearn for the 1977 original. “It’s like this is the movie I wanted it to be, and I’m sorry if you saw half a completed film and fell in love with it,” he said. “But I want it to be the way I want it to be.”

But fans aren’t the only ones who want Lucas to release the original. Curators at the National Film Registry picked the 1977 version of Star Wars to preserve for history’s sake, but they still don’t have a copy in the registry. When they asked for a copy, Lucas refused, saying that he would no longer authorize the release of the original version. The Library of Congress does have a 35mm print of Star Wars, one that was filed in 1978 as part of the movie’s copyright deposit, but the registry, where films are meant to be preserved for history, is still without one.

And here’s the real plot twist. In 1988 George Lucas actually gave a speech before Congress about the importance of cinematic preservation. In the late 1980s, Ted Turner bought studios like MGM and began releasing colorized versions of classic movies. The directors of those movies weren’t happy, and a group of movie makers came together and argued before Congress that people had the right to their cultural heritage, in the form of original versions of classic films.

“People who alter or destroy works of art and our cultural heritage for profit or as an exercise of power are barbarians, and if the laws of the United States continue to condone this behavior, history will surely classify us as a barbaric society,” Lucas said in his speech. He went on:

Today, engineers with their computers can add color to black-and-white movies, change the soundtrack, speed up the pace, and add or subtract material to the philosophical tastes of the copyright holder. Tomorrow, more advanced technology will be able to replace actors with “fresher faces,” or alter dialogue and change the movement of the actor’s lips to match. It will soon be possible to create a new “original” negative with whatever changes or alterations the copyright holder of the moment desires. The copyright holders, so far, have not been completely diligent in preserving the original negatives of films they control. In order to reconstruct old negatives, many archivists have had to go to Eastern bloc countries where American films have been better preserved.

There’s some irony when you compare that quote with the work of Harmy, the fan from the Czech Republic spending hundreds of hours slaving away at restoring Lucas’s original vision.

Some argue that here Lucas was railing against outsiders being able to alter a directors work, not against directors being able to update their own pieces. Which raises the question of who truly owns something like Star Wars—a huge cultural phenomenon—once it is unleashed. Lucas addresses that in his speech too. “American works of art belong to the American public; they are part of our cultural history,” he said.

And while it raises legal questions, Harmy doesn’t think that his work is in any way jeopardizing the value of Star Wars. “I’m convinced that 99% of people who download this already bought Star Wars 10 times over on DVD.”

When Disney bought LucasFilms in 2012, rumors were reignited over the possibility of a true original being released. “I’m really hoping that now that Disney has the rights that they will release the original versions in a proper restored quality, and then I can take all this stuff down and enjoy Star Wars as it’s meant to be,” Harmy told me. But that day may never come. In the meantime, fans will continue to hunt for original copies of the film, and recreate the 1977 movie’s magic.

Have Humans Already Conquered The Threat Of Extinction?

Have Humans Already Conquered The Threat Of Extinction?

by George Dvorsky

The Great Filter theory suggests that all advanced civilizations eventually destroy themselves before acquiring the capacity to colonize space — a notion that could explain why we’ve never been visited by aliens. But there may be another reason for the celestial silence. Yes, the Great Filter exists, but we’ve already passed it. Here’s what this would mean.

Before we can get to the Great Filter hypothesis we have to appreciate what the Fermi Paradox is telling us.

The Fermi Paradox and the Great Silence

The so-called “Great Silence” is the contradictory and counter-intuitive observation that we have yet to see any evidence for the existence of aliens. The size and age of the Universe suggests that many technologically advanced extraterrestrial intelligences (ETIs) ought to exist — but this hypothesis seems inconsistent with the lack of observational evidence to support it.

Despite much of what popular culture and sci-fi would lead us to believe, the fact that we haven’t been visited by ETIs is disturbing. Our galaxy is so ancient that it could have been colonized hundreds, if not thousands, of times over by now. Even the most conservative estimates show that we should have already made contact either directly or indirectly (such as from dormant Bracewell communication probes).

Some skeptics dismiss the Fermi Paradox by suggesting that ETI‘s have come and gone, or that they wouldn’t find us interesting.

Unfortunately, most solutions to the FP don’t hold for a number of reasons, including the realization that a colonization wave of superintelligent aliens would likely rework the fabric of all life in the cosmos (e.g. uplifting), or that these solutions are sociological in nature (i.e. they lack scientific rigor and don’t necessarily apply to the actions of all advanced civilizations; all it would take is just one to think and behave differently —
what astrobiologists refer to as the non-exclusivity problem).

There have been many attempts to resolve the Fermi Paradox, including the herculean attempt by Stephen Webb in his book Fifty Solutions to Fermi’s Paradox and the Problem of Extraterrestrial Life.

If the Universe Is Teeming with Aliens … WHERE IS EVERYBODY?: Fifty
Solutions to the Fermi Paradox and the Problem of Extraterrestrial Life

But one solution stands out from the others,
mostly on account of its brute elegance: The Great Filter.

The Great Filter

Conceived in 1998 by Robin Hanson, the GF is the disturbing suggestion that there is some kind of absurdly difficult step in the evolution of life — one that precludes it from becoming interstellar.

And like the immutable laws of the universe, the GF is a stumbling block that holds true across the board; if it applies here on Earth, it applies everywhere.

Many look upon the GF as evidence that we’ll destroy ourselves in the future. The basic idea is that every civilization destroys itself before developing space-faring technologies, hence the empty cosmos. Given our own trajectory and the ominous presence of apocalyptic weapons, this scenario certainly seems plausible. We’re not even close to going interstellar, yet we’re certainly capable of self-annihilation.

But that doesn’t mean this interpretation of the GF is the correct one. Rather, it’s quite possible that human civilization has already passed the Great Filter. Should this be the case, it would be exceptionally good news. Assuming there’s no other filter awaiting us in the future, it means we might be the first and only intelligent civilization in the Milky Way.

It’s a possibility, however, that demands explanation. If the filter is behind us, what was it? And how did we manage to get past it? Interestingly, there are some excellent candidates.

Rare Earth

First and foremost there’s the Rare Earth Hypothesis (REH), the suggestion that the emergence of life was extremely improbable for a confluence of reasons. The theory essentially suggests that we hit the jackpot here on Earth.

Amazon.com: $13.50

This argument, which was first articulated by geologist Peter Ward and astrobiologist Donald E. Brownlee, turns the whole Copernican Principle on its head. Instead of saying that we’re nothing special or unique, the REH implies the exact opposite — that we are freakishly special and unique. What we see here on Earth in this solar system and in this part of the Galaxy may be a remarkable convergence of highly unlikely factors — factors that have resulted in a perfect storm of conditions suitable for the emergence of complex life.

It’s important to note that Ward and Brownlee are not implying that it’s one or two conditions that can explain habitability, but rather an entire array of happy accidents. For example, stars might have to be of the right kind (including adequate metallicity and safe distance from dangerous celestial objects), and planets must be in a stable orbit with a large moon. Other factors include the presence of gas giants, plate tectonics, and many others.

But even with all the right conditions, life was by no means guaranteed. It’s quite possible that the Great Filter involved the next set of steps: the emergence of life and its ongoing evolution.

The Improbability of Life

Indeed, in addition to the various cosmological and chemical prerequisites for life, there were at least three critical stages that could all be considered candidates for the Great Filter: (1) the emergence of reproductive molecules (abiogenesis and the emergence of RNA), (2) simple single-celled life (prokaryotes), and (3) complex single-celled life (eukaryotes).

Have Humans Already Conquered The Threat Of Extinction?

Chemists and biologists are still not entirely sure how the first self-replicating molecules came into existence. Unlike its big brother DNA, RNA is a single-stranded molecule that has a much shorter chain of nucleotides. Moreover, it usually needs DNA to reproduce itself, which would have been a problem given the absence of DNA in those early days.

That said, scientists know that RNA is capable of reproducing through autocatalysis. It does this by storing information similar to DNA, which allows it to become its own catalyst (a ribosome). This so-called RNA World Model suggests that RNA can function as both a gene and an enzyme — a pre-DNA configuration that eventually became the basis for all life.

Given that we’ve never detected life elsewhere, it’s difficult to know how difficult this initial step was. But that said, this form of life emerged super-early in the Earth’s history — about a billion years after its formation, and immediately after the cooling of rocks and the emergence of oceans.

But what we do know is that the next few steps — the leap from single-celled life to complex single-celled life — was exceedingly difficult, if not highly improbable. The process of copying a genetic molecule is extremely complex, involving the perfect configuration of proteins and other cellular components.

Here’s how it likely happened: Once a self-replicating molecule emerged, the presence of RNA allowed for the formation of protobionts, a theoretic precursor to prokaryotic cells. These tightly bound bundles of organic molecules contained RNA within their membranes, which could have evolved into proper prokaryotic cells.

And here’s where it gets interesting. After the formation of prokaryotes (about 3.5 billion years ago) nothing changed in the biological landscape for the next 1.8 billion years. Life in this primitive form was completely stuck. Imagine that — no evolution for almost two billion years. It was only after the endosymbiosis of multiple prokaryotes that complex single-cell life finally emerged — a change that was by no means guaranteed, and possibly unlikely.

And it’s this highly improbable step, say some scientists, that’s the Great Filter. Everything that happened afterward is a complete bonus.

Now that said, there may have been other filters as well. These could include the emergence of terrestrial organisms, hominids, and various civilizational stages, like the transition from stone age culture to agricultural to industrial. But unlike the first primordial stages already discussed, these are porous filters and not terribly unlikely.

More Filters Ahead?

So, if the GF is behind us, it would do much to explain the Fermi Paradox and the absence of extraterrestrial influence on the cosmos. Should that be the case, we may very well have a bright future ahead of us. The Milky Way Galaxy is literally ours for the taking, our future completely open-ended.

But before we jump to conclusions, it’s only fair to point out that we’re not out of the woods yet. There could very well be another GF in the future — one just as stingy as the filters of our past. The universe, while giving the appearance of bio-friendliness, may in reality be extremely hostile to intelligent life.

Mystery of moving boulders in Death Valley solved

How Do Death Valley’s “Sailing Stones” Move Themselves Across the Desert?

By Joseph Stromberg

These mysterious rocks have puzzled scientists for decades
—until one geologist found the answer on his kitchen table

Start at the Furnace Creek visitor center in Death Valley National Park. Drive 50 miles north on pavement, then head west for another 30 miles on bone-rattling gravel roads. During the drive—which will take you four hours if you make good time—you’ll pass sand dunes, a meteor crater, narrow canyons, solitary Joshua trees and virtually no evidence of human existence whatsoever.  But soon after cresting the Cottonwood Mountains, you’ll come upon a landscape so out of place even in this geologically bizarre park that it almost seems artificial.

Racetrack Playa is a dried-up lakebed, ringed by mountains, about 3 miles long and flat as a tabletop. During summer, the cracked floor looks prehistoric under the desert sun; during winter, it’s intermittently covered by sheets of ice and dustings of snow. But the dozens of stones scattered across the playa floor are the most puzzling part of the view. Ranging from the size of a computer mouse to a microwave, each one is followed by a track etched into the dirt, like the contrail behind an airplane. Some tracks are straight and just a few feet long, while others stretch the length of a football field and curve gracefully or jut off at sharp angles.

Staring at these “sailing stones,” you’re torn between a pair of certainties that are simply not compatible: (1) these rocks appear to have moved, propelled by their own volition, across the flat playa floor, and yet (2) rocks don’t just move themselves.

“It’s very quiet out there, and it’s very open, and you tend to have the playa to yourself,” says Alan Van Valkenburg, a park ranger who has worked at Death Valley for nearly 20 years. “And the longer you stay out there, it just takes on this incredible sense of mystery.” The mystery is rooted in an extraordinary fact: No one has ever actually seen the rocks move.

Explanations for the stones’ movement have tended towards the absurd (magnetism, aliens and mysterious energy fields, for example). Some present-day visitors apparently agree—Van Valkenburg notes that stone theft is a growing problem, perhaps because of perceived special properties. “I don’t know whether people think they’re ‘magic rocks,’” he says. “But of course, as soon as you remove them from the playa, all ‘magic’ is lost.”

But if they’re not magic, what really does cause the stones to sail? In 1948, two USGS geologists named Jim McAllister and Allen Agnew set out to answer the question. They proposed that dust devils caused the strange movement, perhaps in combination with the playa’s intermittent flooding. In 1952, another geologist tested this hypothesis as directly as he knew how: He soaked a stretch of the playa and used a plane’s propeller to create powerful winds. Results were inconclusive.

In the following decades, theories drifted towards ice, which can occasionally form on the playa during the winter. During the early 1970s, a pair of geologists—Robert Sharp of Cal Tech and Dwight Carey of UCLA—attempted to settle once and for all whether ice or wind was responsible. The team visited the Racetrack twice a year and meticulously tracked the movements of 30 stones, giving them names (Karen, the largest boulder, was 700 pounds). They planted wooden stakes around the stones, surmising that if ice sheets were responsible, the ice would be frozen to the stakes, thereby immobilizing the stones. But some stones still escaped—and despite frequent visits, the pair never saw one move.

Still, ice remained the primary hypothesis for decades. John Reid, a Hampshire College professor, took student groups to the playa annually from 1987 to 1994 to study the stones. Because of the many parallel tracks, he came away convinced that they were locked together in large ice sheets that were blown by strong winds.

But Paula Messina, a geologist at San Jose State, used GPS to create a digital map of the tracks and found that most were, in fact, not parallel. Furthermore, wind-based models were thrown into doubt when researchers attempted to calculate the wind speeds necessary to move the ice sheets. The lowest figures were hundreds of miles per hour.

Enter Ralph Lorenz, a planetary scientist at Johns Hopkins University. In 2006, as part of a project with NASA, Lorenz was setting up a network of miniaturized weather stations in Death Valley. The weather is harsh enough there to serve an analogue for weather conditions on Mars. But then he discovered the sailing stones. “I was intrigued, as everyone is, and I had this instrumentation I was using in desert locations during the summer,” he says. “We realized we could use it during the winter and try to understand what the conditions really are at the playa.”

As the research team studied weather patterns on the Racetrack, they also looked for rocks that seemed to move on their own in other environments. Scanning the scientific literature, Lorenz learned that the buoyancy of ice helped float boulders onto arctic tidal beaches, creating barricades along the shore. The scientists began putting this idea together with what they saw on the Racetrack. “We saw one instance where there was a rock trail and it looked like it hit another rock and bounced, but the trail didn’t go all the way up to the other rock, like it was repelled somehow,” says Lorenz. “We thought if there was a collar of ice around the rock, then it might be easy to imagine why it might bounce.”

Eventually, Lorenz employed a tried-and-true method for testing his nascent idea: the kitchen-table experiment. “I took a small rock, and put it in a piece of Tupperware, and filled it with water so there was an inch of water with a bit of the rock sticking out,” he says. “I put it in the freezer, and that then gave me a slab of ice with a rock sticking out of it.” He flipped the rock-ice hybrid upside down and floated it in a tray of water with sand on the bottom. By merely blowing gently on the ice, he realized, he could send the embedded rock gliding across the tray, scraping a trail in the sand as it moved. After decades of theoretical calculations by countless scientists, the answer seemed to be sitting on his tabletop.

Lorenz and his team presented their new model in a 2011 paper. “Basically, a slab of ice forms around a rock, and the liquid level changes so that the rock gets floated out of the mud,” he explains. “It’s a small floating ice sheet which happens to have a keel facing down that can dig a trail in the soft mud.” Calculations show that, in this scenario, the ice causes virtually no friction on the water, so the stones are able to glide with just a slight breeze. The team argues that their model accounts for the movement far better than any other, since it doesn’t require massive wind speeds or enormous ice sheets.

Still, says Ranger Van Valkenburg, most visitors to the Racetrack seem to resist this concrete explanation for such a peculiar phenomenon. “People always ask, ‘what do you think causes them to move?’ But if you try to explain, they don’t always want to hear the answers,” he says. “People like a mystery—they like an unanswered question.”

In a way, though, Lorenz’ physical explanation really need not diminish the feeling of awe the sailing stones bring about—it can heighten it. You can get a sense of it by sitting at the playa and imagining the perpetual sailing of the stones over time, stretching into millennia. As human societies rise and fall, and as cities are constructed and then left to disintegrate, the stones will glide gradually around their playa, turning back and forth. Frozen in ice and nudged by the slightest of breezes, they will endlessly carve mysterious, zigzagging paths into the hard flat ground.

Air Travel Is Becoming Inhumane, And It Won’t Change As Long As Airlines Remain Greedy

Air Travel Is Becoming Inhumane, And It
Won’t Change As Long As Airlines Remain Greedy

by John Haltiwanger

No one likes having his or her space invaded. We all need a little wiggle room and it’s anxiety-inducing to feel confined. This is particularly true while traveling. Anyone who has ever traveled on an airplane can likely sympathize with this sentiment.

Let’s face it: Traveling is stressful, and it’s often extremely uncomfortable.

First, you have to pack and ensure that your luggage isn’t too heavy or you’ll have to pay extra. Then, you have to get to the airport, check your baggage and make it to security. At security, you might even be lucky enough to get pulled aside to be groped by a total stranger.

You finally make it to your gate, but it’s another two hours until your flight, or even worse, it’s been delayed.

Finally, it’s time to board. Every passenger shuffles quickly into line, despite the fact that everyone has assigned seats and you’re all going to the same place. There’s really no need to rush, but for some reason, everyone always does.

What’s more, you’re likely sleep deprived, or maybe even jet-lagged. Like everyone else around you, your patience is wearing thin, and you just want to get to where you’re going in peace.

At long last, you get to your seat. You’re ready to get comfortable, possibly have a drink, watch a movie and doze off until you reach your destination. However, almost immediately after takeoff, the person in front of you reclines his or her chair, and you have no room to move your legs.

You politely ask the person to return the chair to its normal position, but you’re denied. What do you do next? Would you start a fight?

In the past week, two fights have broken out on airplanes over disputes surrounding passengers reclining their chairs. In both incidents, the flights were diverted and forced to land early.

When it comes down to it, flying is becoming increasingly more stressful as airlines continue to decrease the amount of room they provide for passengers. On top of the increase in added fees, planes are getting more and more crowded.

Two decades ago, passengers were given around 34 inches of legroom on a flight. Today, they are only given around 28 inches, and it’s only going to get lesser. This is a 10 percent decrease in space.

Why are airlines doing this? Profit. They want to fit as many people on a plane as possible, and also encourage people to upgrade to more comfortable settings in business or first class by paying more for their tickets.

Airlines like Air Canada are a prime example of this, but they are not alone in this strategy. A lot of airline companies from the United States are actively taking out older, more spacious seats and replacing them with smaller, lighter and more confined ones.

The seats not only mean more passengers, but also less weight and reduced fuel costs.

One might argue that the desire to increase profits by denying customers basic comforts is inhumane. It’s unhealthy to sit for long periods of time. Furthermore, when people are squeezed into confined spaces, the likelihood of them being able to get up and move around diminishes exponentially.

Moreover, as the Center for Disease Control notes, blood clots are a serious risk for people traveling long-distances:

… Anyone traveling more than four hours, whether by air, car, bus, or train, can be at risk for blood clots.

Blood clots can form in the deep veins (veins below the surface that are not visible through the skin) of your legs during travel because you are sitting still in a confined space for long periods of time.

The longer you are immobile, the greater is your risk of developing a blood clot… A serious health problem can occur when a part of the blood clot breaks off and travels to the lungs causing a blockage.  This is called a pulmonary embolism, and it may be fatal.

The process of traveling is stressful enough without the lack of space. In fact, in 2007, a neuropsychologist argued that passing through Heathrow Airport induced the same amount of mental stress as encountering a riot.

The decision of airlines to decrease legroom in planes is bad for both the psychological and physical health of passengers. Simply put, the airlines are to blame here, not the people. By seeking higher profits and lowering the quality of air travel, they are increasing the likelihood of confrontations on flights.

As more flights get diverted due to related issues, perhaps airlines will lose profits and change their policies. In a perfect world, they would have a bit more integrity and provide enough space for people to travel in comfort and safety.

Until that time, we might all have to settle for less legroom. Or, you could consider chartering a private jet?

NASA Sets A 2018 Launch Date For The Rocket That Will Take Us To Mars

NASA Sets A 2018 Launch Date For The Rocket That Will Take Us To Mars

by Robbie Gonzalez

Three years after its unveiling, NASA managers have approved the development of the rocket that will carry astronauts into deep space. Called the Space Launch System (SLS), the heavy-lift rocket will be the most powerful ever built, and is designed to launch the next generation of space explorers to deep-space worlds well beyond Earth’s moon.

NASA has unveiled the rocket that will take us to Mars

Say hello to NASA’s Space Launch System (SLS) — it’s about to become the largest, most powerful space rocket we’ve ever built.

The Agency announced a design for the rocket earlier today, saying it will be a “safe, affordable and sustainable means of reaching beyond our current limits and opening up new discoveries from the unique vantage point of space.” Buckle up, everybody — we’re going to Mars.

The announcement comes just days after NASA initiated construction of the first space-bound version of its Orion Multi-Purpose Crew Vehicle (MPCV), the crew capsule designed to carry astronauts deeper into space than they’ve ever been.

The SLS and Orion MPCV are both part of the 2010 NASA Authorization Act signed last October by U.S. President Barack Obama, who has charged the US Space Agency with putting humanity on Mars by the 2030’s. And the SLS is the heavy-lift rocket designed to get us there.

According to NASA, the SLS rocket will “incorporate technological investments” and “proven hardware” from previous space exploration programs. But what does that mean?

Remember the shuttles we shelved just a few months ago? Well various parts of the new shuttle will be reminiscent of those — only bigger and badder. Numerous components on the SLS, ranging from its fuel tanks to its rocket boosters, will be based on up-scaled and upgraded versions of technologies featured on retired NASA tech.

NASA hopes that this “evolvable development approach” will allow for quick but cost-effective progress over the next few years, allowing them to meet the 2017 deadline that they’ve set for the rocket’s first, unmanned test flight. NASA says the SLS will have an initial lift capacity of 70 metric tons, but that this capacity will be “evolvable” to an unprecidented 130 metric tons.

2018 Launch Date For The Rocket To Mars

The SLS’s maiden flight, dubbed “EM-1” is slated for November, 2018, and will catapult an uncrewed Orion spacecraft on a three-week test flight beyond the Moon. That’s a year later than officials had originally hoped, but was reportedly necessary to assess the technological and financial investments necessary to deliver on a spacecraft initially billed as a “safe, affordable and sustainable means of reaching beyond our current limits and opening up new discoveries from the unique vantage point of space.”

“After rigorous review, we’re committing today to a funding level and readiness date that will keep us on track to sending humans to Mars in the 2030s – and we’re going to stand behind that commitment,” said Associate Administrator Robert Lightfoot, at a press briefing held on Wednesday. “Our nation is embarked on an ambitious space exploration program.”

“We are making excellent progress on SLS designed for missions beyond low Earth orbit,” he said. “We owe it to the American taxpayers to get it right.”

NASA Sets A 2018 Launch Date For The Rocket That Will Take Us To Mars

Republican Reaction to Ferguson Shows They Cannot be Trusted to Govern America

Republican Reaction to Ferguson Shows They Cannot be Trusted to Govern America

By Hrafnkell Haraldsson

Kevin Sorbo, not content to hate on atheists, has added blacks to his list by claiming that the protesters in Ferguson, MO, are “animals” and “losers.”

TV’s Hercules is starting to sound like Joe the Plumber, or Ted Nugent. And America, as you can see from the photo below, is starting to look like an American run by Ted Nugent.

Pictures, as they say, are worth a thousand words. In my thousand words then, I shall try to go deeper than this AP photo, or to at least provide some useful context.

“Ferguson riots have very little to do with the shooting of the young man. It’s an excuse to be the losers these animals truly are,” Sorbo wrote on Facebook, and that is certainly how the police sniper above seems to feel.

Sorbo’s Facebook post that has since been removed and replaced by an ” apology.”

The police have yet to apologize.

What Sorbo originally wrote was,

It is a tipping point to frustration built up over years of not trying, but blaming everyone else. The Man, for their failures. It’s always someone else’s fault when you give up.

That sounds like the House of Representatives to me. Sorbo has described John Boehner to a tee.

Sorbo said that the death of Mike Brown should serve as a “reminder to the African Americans that their president they voted in has only made things worse for them, not better.”

Their president. Not Sorbo’s.

And don’t get excited by his so-called apology. What he says is, “Yes. I am an idiot and do hold myself accountable for the way my post came off.”

Not what he felt, but how it came off. As apologies go, it’s not much of an apology. But then, what conservative apology is?

What Sorbo told TMZ is that he was, like politicians, “taken out of context”:

Like politicians always say, things are taken out of context,” he said. “Look, I’ve got plenty of friends from all races and all religions and all colors and all breeds. I’m hardly a racist.
Oh, I don’t know, I think the context was pretty clear. Much more telling was his previous claim that the protesters in Ferguson, MO, are “animals” and “losers.”

And for Sorbo, the media are “nothing more than agitators.”

The media promote chaos to boost their pathetic ratings. We should shut them all off and watch clips on the internet only when republished under fair use by a conservative media watchdog group.”
Oh boy. Sorbo is pumping in the Kool Aid via IV. He’s not even drinking it anymore. A conservative watch dog group. Really. Why bother when we have Fox News editing clips 24/7 to make Obama say things he never said.

We’ve already got Fox News’ expert assessment of Ferguson from a member of their Medical A-Team, Keith Ablow, who says Ferguson residents hate whites (heck, I’m white, and I’m beginning to hate me some whites too) and are psychologically suspect.

Sorbo’s suggestion is like suggesting we ask Joseph Goebbels to tell us about the Jews. Of course, that logic behind that no doubt sounds perfectly reasonable to conservatives, who love to ask the people responsible for America’s debacle in Iraq and Afghanistan to tell us how to solve the problems they created.

This is all disgusting.

Is it less disgusting than Ben Carson’s claim that it wasn’t the police who killed Mike Brown, but political correctness and the young man’s lack of a father figure? Carson, one of the GOP’s token blacks, wants the “agitators” and “criminals” in Ferguson punished, saying they need to “teach [their] children to respect authority.”

This is pretty much like Ted Nugent’s World Net Daily piece blaming liberalism for the death of Mike Brown, not conservative fueled racism, like his own. If President Obama is a sub-human mongrel to Nugent, what are the folks of Ferguson?

It’s a shame Kevin Sorbo again fails to see the extent to which Nugent’s column is an example of “blaming everyone else.”

Like Laura Ingraham, Carson praised Cliven Bundy and his gang of rebels. At that time, with a wealthy white man involved, it was important to “stand up against the government” and martial law was a sign of government oppression.

Carson also got with Steve Malzberg of Newsmax to compare the Ferguson protestors with Hamas. Crazy as it sounds to compare the people of Ferguson to Hamas, Carson told Malzberg that “political correctness is in the process of destroying this nation.”

 

So no, Kevin Sorbo is far from alone in demonizing the people of Ferguson, MO, who have lost not only some of their numbers to police bullets, but even their status as human beings. They have become not frustrated people dealing with rampant racism and oppression, but terrorists.

America’s conservatives have proved in the wake of the killing of Mike Brown that minorities will have no justice under Republican governance. They can expect to be controlled, however, and taught authority via tear gas and bullet.

Token blacks like the Quisling Ben Carson will cheer them on.

In Republican America, white folks are the real victims, particularly the fake-Christian variety, and every time conservative fueled hate results in another victim, Republicans know who to blame: liberals and the black victims themselves, who, we are told, are literally begging for the police to shoot them.

The sad truth is that Republicans could shoot Mike Brown, so in a collective sense, they did. They can’t shoot President Obama, though they’d like to, so they’ll settle for tearing America apart around him, suing him, impeaching him, and throwing him in prison where they have proven they think black men belong.

Republicans are outraged that in the wake of these egregious examples of racism that blacks in Ferguson are registering to vote, but the real impetus to vote comes not from liberals, but from the Republicans themselves, who have made the most compelling argument possible that they cannot be trusted to govern America.

 

Radical New Theory Could Kill the Multiverse Hypothesis

Radical New Theory Could Kill the Multiverse Hypothesis

By Natalie Wolchover

Though galaxies look larger than atoms and elephants appear to outweigh ants, some physicists have begun to suspect that size differences are illusory. Perhaps the fundamental description of the universe does not include the concepts of “mass” and “length,” implying that at its core, nature lacks a sense of scale.

This little-explored idea, known as scale symmetry, constitutes a radical departure from long-standing assumptions about how elementary particles acquire their properties. But it has recently emerged as a common theme of numerous talks and papers by respected particle physicists. With their field stuck at a nasty impasse, the researchers have returned to the master equations that describe the known particles and their interactions, and are asking: What happens when you erase the terms in the equations having to do with mass and length?

Nature, at the deepest level, may not differentiate between scales. With scale symmetry, physicists start with a basic equation that sets forth a massless collection of particles, each a unique confluence of characteristics such as whether it is matter or antimatter and has positive or negative electric charge. As these particles attract and repel one another and the effects of their interactions cascade like dominoes through the calculations, scale symmetry “breaks,” and masses and lengths spontaneously arise.

Similar dynamical effects generate 99 percent of the mass in the visible universe. Protons and neutrons are amalgams — each one a trio of lightweight elementary particles called quarks. The energy used to hold these quarks together gives them a combined mass that is around 100 times more than the sum of the parts. “Most of the mass that we see is generated in this way, so we are interested in seeing if it’s possible to generate all mass in this way,” said Alberto Salvio, a particle physicist at the Autonomous University of Madrid and the co-author of a recent paper on a scale-symmetric theory of nature.

In the equations of the “Standard Model” of particle physics, only a particle discovered in 2012, called the Higgs boson, comes equipped with mass from the get-go. According to a theory developed 50 years ago by the British physicist Peter Higgs and associates, it doles out mass to other elementary particles through its interactions with them. Electrons, W and Z bosons, individual quarks and so on: All their masses are believed to derive from the Higgs boson — and, in a feedback effect, they simultaneously dial the Higgs mass up or down, too.

The multiverse ennui can’t last forever.

The new scale symmetry approach rewrites the beginning of that story.
“The idea is that maybe even the Higgs mass is not really there,” said Alessandro Strumia, a particle physicist at the University of Pisa in Italy. “It can be understood with some dynamics.”

The concept seems far-fetched, but it is garnering interest at a time of widespread soul-searching in the field. When the Large Hadron Collider at CERN Laboratory in Geneva closed down for upgrades in early 2013, its collisions had failed to yield any of dozens of particles that many theorists had included in their equations for more than 30 years. The grand flop suggests that researchers may have taken a wrong turn decades ago in their understanding of how to calculate the masses of particles.

“We’re not in a position where we can afford to be particularly arrogant about our understanding of what the laws of nature must look like,” said Michael Dine, a professor of physics at the University of California, Santa Cruz, who has been following the new work on scale symmetry. “Things that I might have been skeptical about before, I’m willing to entertain.”

The Giant Higgs Problem

The scale symmetry approach traces back to 1995, when William Bardeen, a theoretical physicist at Fermi National Accelerator Laboratory in Batavia, Ill., showed that the mass of the Higgs boson and the other Standard Model particles could be calculated as consequences of spontaneous scale-symmetry breaking. But at the time, Bardeen’s approach failed to catch on. The delicate balance of his calculations seemed easy to spoil when researchers attempted to incorporate new, undiscovered particles, like those that have been posited to explain the mysteries of dark matter and gravity.

Instead, researchers gravitated toward another approach called “supersymmetry” that naturally predicted dozens of new particles. One or more of these particles could account for dark matter. And supersymmetry also provided a straightforward solution to a bookkeeping problem that has bedeviled researchers since the early days of the Standard Model.

In the standard approach to doing calculations, the Higgs boson’s interactions with other particles tend to elevate its mass toward the highest scales present in the equations, dragging the other particle masses up with it. “Quantum mechanics tries to make everybody democratic,” explained theoretical physicist Joe Lykken, deputy director of Fermilab and a collaborator of Bardeen’s. “Particles will even each other out through quantum mechanical effects.”

This democratic tendency wouldn’t matter if the Standard Model particles were the end of the story. But physicists surmise that far beyond the Standard Model, at a scale about a billion billion times heavier known as the “Planck mass,” there exist unknown giants associated with gravity. These heavyweights would be expected to fatten up the Higgs boson — a process that would pull the mass of every other elementary particle up to the Planck scale. This hasn’t happened; instead, an unnatural hierarchy seems to separate the lightweight Standard Model particles and the Planck mass.

Hypothetical particles believed to exist at the Planck scale (right) are about a billion billion times heavier than the known particles (left). The tendency of particle masses to equalize in calculations makes this a puzzling hierarchy.

With his scale symmetry approach, Bardeen calculated the Standard Model masses in a novel way that did not involve them smearing toward the highest scales. From his perspective, the lightweight Higgs seemed perfectly natural. Still, it wasn’t clear how he could incorporate Planck-scale gravitational effects into his calculations.

Meanwhile, supersymmetry used standard mathematical techniques, and dealt with the hierarchy between the Standard Model and the Planck scale directly. Supersymmetry posits the existence of a missing twin particle for every particle found in nature. If for each particle the Higgs boson encounters (such as an electron) it also meets that particle’s slightly heavier twin (the hypothetical “selectron”), the combined effects would nearly cancel out, preventing the Higgs mass from ballooning toward the highest scales. Like the physical equivalent of x + (–x) ≈ 0, supersymmetry would protect the small but non-zero mass of the Higgs boson. The theory seemed like the perfect missing ingredient to explain the masses of the Standard Model — so perfect that without it, some theorists say the universe simply doesn’t make sense.

Yet decades after their prediction, none of the supersymmetric particles have been found. “That’s what the Large Hadron Collider has been looking for, but it hasn’t seen anything,” said Savas Dimopoulos, a professor of particle physics at Stanford University who helped develop the supersymmetry hypothesis in the early 1980s. “Somehow, the Higgs is not protected.”

The LHC will continue probing for convoluted versions of supersymmetry when it switches back on next year, but many physicists have grown increasingly convinced that the theory has failed. Just last month at the International Conference of High-Energy Physics in Valencia, Spain, researchers analyzing the largest data set yet from the LHC found no evidence of supersymmetric particles. (The data also strongly disfavors an alternative proposal called “technicolor.”)

The theory has what most experts consider a serious flaw:
It requires the existence of strange particle-like entities called “ghosts.”

The implications are enormous. Without supersymmetry, the Higgs boson mass seems as if it is reduced not by mirror-image effects but by random and improbable cancellations between unrelated numbers — essentially, the initial mass of the Higgs seems to exactly counterbalance the huge contributions to its mass from gluons, quarks, gravitational states and all the rest. And if the universe is improbable, then many physicists argue that it must be one universe of many: just a rare bubble in an endless, foaming “multiverse.” We observe this particular bubble, the reasoning goes, not because its properties make sense, but because its peculiar Higgs boson is conducive to the formation of atoms and, thus, the rise of life. More typical bubbles, with their Planck-size Higgs bosons, are uninhabitable.

“It’s not a very satisfying explanation, but there’s not a lot out there,” Dine said.

As the logical conclusion of prevailing assumptions, the multiverse hypothesis has surged in begrudging popularity in recent years. But the argument feels like a cop-out to many, or at least a huge letdown. A universe shaped by chance cancellations eludes understanding, and the existence of unreachable, alien universes may be impossible to prove. “And it’s pretty unsatisfactory to use the multiverse hypothesis to explain only things we don’t understand,” said Graham Ross, an emeritus professor of theoretical physics at the University of Oxford.

The multiverse ennui can’t last forever.

“People are forced to adjust,” said Manfred Lindner, a professor of physics and director of the Max Planck Institute for Nuclear Physics in Heidelberg who has co-authored several new papers on the scale symmetry approach. The basic equations of particle physics need something extra to rein in the Higgs boson, and supersymmetry may not be it. Theorists like Lindner have started asking, “Is there another symmetry that could do the job, without creating this huge amount of particles we didn’t see?

Wrestling Ghosts

Picking up where Bardeen left off, researchers like Salvio, Strumia and Lindner now think scale symmetry may be the best hope for explaining the small mass of the Higgs boson. “For me, doing real computations is more interesting than doing philosophy of multiverse,” said Strumia, “even if it is possible that this multiverse could be right.”

For a scale-symmetric theory to work, it must account for both the small masses of the Standard Model and the gargantuan masses associated with gravity. In the ordinary approach to doing the calculations, both scales are put in by hand at the beginning, and when they connect in the equations, they try to even each other out. But in the new approach, both scales must arise dynamically — and separately — starting from nothing.

“The statement that gravity might not affect the Higgs mass is very revolutionary,” Dimopoulos said.

A theory called “agravity” (for “adimensional gravity”) developed by Salvio and Strumia may be the most concrete realization of the scale symmetry idea thus far. Agravity weaves the laws of physics at all scales into a single, cohesive picture in which the Higgs mass and the Planck mass both arise through separate dynamical effects. As detailed in June in the Journal of High-Energy Physics, agravity also offers an explanation for why the universe inflated into existence in the first place. According to the theory, scale-symmetry breaking would have caused an exponential expansion in the size of space-time during the Big Bang.

However, the theory has what most experts consider a serious flaw: It requires the existence of strange particle-like entities called “ghosts.” Ghosts either have negative energies or negative probabilities of existing — both of which wreak havoc on the equations of the quantum world.

“Negative probabilities rule out the probabilistic interpretation of quantum mechanics, so that’s a dreadful option,” said Kelly Stelle, a theoretical particle physicist at Imperial College, London, who first showed in 1977 that certain gravity theories give rise to ghosts. Such theories can only work, Stelle said, if the ghosts somehow decouple from the other particles and keep to themselves. “Many attempts have been made along these lines; it’s not a dead subject, just rather technical and without much joy,” he said.

Strumia and Salvio think that, given all the advantages of agravity, ghosts deserve a second chance. “When antimatter particles were first considered in equations, they seemed like negative energy,” Strumia said. “They seemed nonsense. Maybe these ghosts seem nonsense but one can find some sensible interpretation.”

Meanwhile, other groups are crafting their own scale-symmetric theories. Lindner and colleagues have proposed a model with a new “hidden sector” of particles, while Bardeen, Lykken, Marcela Carena and Martin Bauer of Fermilab and Wolfgang Altmannshofer of the Perimeter Institute for Theoretical Physics in Waterloo, Canada, argue in an Aug. 14 paper that the scales of the Standard Model and gravity are separated as if by a phase transition. The researchers have identified a mass scale where the Higgs boson stops interacting with other particles, causing their masses to drop to zero. It is at this scale-free point that a phase change-like crossover occurs. And just as water behaves differently than ice, different sets of self-contained laws operate above and below this critical point.

To get around the lack of scales, the new models require a calculation technique that some experts consider mathematically dubious, and in general, few will say what they really think of the whole approach. It is too different, too new. But agravity and the other scale symmetric models each predict the existence of new particles beyond the Standard Model, and so future collisions at the upgraded LHC will help test the ideas.

In the meantime, there’s a sense of rekindling hope.

“Maybe our mathematics is wrong,” Dine said. “If the alternative is the multiverse landscape, that is a pretty drastic step, so, sure — let’s see what else might be.”

The Dirty Secret Doctors Don’t Want You To Know

The Dirty Secret Doctors Don’t Want You To Know

by Kent Sepkowitz

A new book about a doctor’s first year as a medical examiner reveals all sorts of grisly detail, but none so alarming as a trade secret the rest of us are perhaps better off not knowing.

Doctors are much weirder than anyone realizes. We are people who, despite ourselves, find ourselves drawn to the sick, the dying, the permanently bruised. It surely is perverse. It surely edges into a morally indefensible territory. It surely however gives a certain type of feller a thrill, dark and shameful though it may be. You know that unusual illness your grandmother had a few years ago? The one with the fever and the rash and the kidney failure that eventually killed her? You all call it a family tragedy—we doctors call it a great case.Before consulting the rabbis and priests for moral pronouncements, however, please realize that we aren’t the only ones—take the undertakers. They too love a good death, a brilliant corpse, a riveting sequence of unfortunate events. Their eagerness for the extreme and the extremely awful may surpass even our own, so pleased are they with their restorative skills. One only need read the classic book by the poet-mortician Thomas Lynch, The Undertaking: Life Studies from the Dismal Trade, to appreciate how far pride of place has migrated.

For those who want a deeper look at this sort of psychopathology (from which I too suffer, gravely), the two involved professional groups have met up in Working Stiff: Two Years, 262 Bodies, and the Making of a Medical Examiner by Dr. Judy Melinek and her husband, T.J. Mitchell. Melinek is the fledgling medical examiner in question, choosing to pursue that macabre branch of medicine that determines how newly dead people died—murder or accident or suicide or old age. Their timing is apt: The medical examiner is now a hot commodity in TV-land. Countless shows, from Quincy to Bones to NCIS: Everywhere, have a usually crusty, sometimes sexy, but always aloof medical examiner at the center of the drama.

 Melinek and Mitchell write about Melinek’s time a decade ago as a training doctor in the New York City Medical Examiner’s office, where she did autopsies on decomposing men tossed into dumpsters, children scalded to death, various drug addicts who shot too much heroin, bodies that washed ashore or fell a distance to splat onto pavement, and those found—because of the rotting smell—dead in their apartment. The details are vivid and somewhat unimaginable; they also run together. To offset this potential monotony, the authors weave through the many vignettes the sad personal tale of Dr. Melinek’s own father’s suicide as a youngish man of 37, even mentioning the Medical Examiner’s description of her father’s autopsy.

The book is at times fun, at other times chilling, but it also can be quite glib. For example, in the chapter entitled “Death at the Hand of Another,” the authors describe Dr. Melinek’s excitement as she determined the relationship between a bullet’s trajectory and the inferred sequence of events that killed a man. “‘That is so cool!’ I proclaimed to Barb and Renee, the tech, when I saw the point of my probe emerge from the dead man’s flayed brow.” Another story, this one in the chapter uncomically titled “Stinks and Bones,” refers to a mostly decomposed anonymous body with a penis “clinging valiantly to the front of the pubic bone”—a comment perhaps better left unwritten or unsaid anywhere in society—except perhaps the autopsy table.

Make no mistake though—this sort of insider jargon, glib though it may be, is absolutely the coin of every hospital’s realm and indeed could be said to make any health-care facility more functional by giving practitioners a chance to blow off verbal steam. Every group, under pressure, needs its own strange barks and twitches, from U.S. senators to defensive linemen to the guy rewiring your cable box. Not surprisingly, MedSpeak is a very coarse, very colorful, very cruel argot that doctors learn to speak from the first days of medical school, perfect after a decade or so and practice religiously—right up to that moment in middle age when they find themselves surrounded by friends and loved ones who occupy not chairs and sofas but rather hospital beds and CT scanners. Then the jollity of gallows humor, the need to show sang-froid despite the obvious impropriety, yields to the frigid touch of one’s own impending doom.

What the authors hint at with their coy descriptions of the very dead, but seem to avoid meeting head-on, is the aforementioned up-is-down doctor problem—our trademark love of illness. Within that passion for decrepitude, unstated but never out of view, is the working premise for the whole deal: that somehow we can look death square in the eye because we are not eligible for the squad—a new sort of diplomatic immunity really worth fighting for.

140821-sepkowitz-working-stiff-embed
‘Working Stiff: Two Years, 262 Bodies, and the Making
of a Medical Examiner’ by Judy Melinek, MD & T.J. Mitchell. 272 pgs. 

 

And the deeper we go—by, say, becoming a forensic pathologist or a pediatric oncologist—the more confident we are that this hyper-haunted house experience will strengthen our diplomatic immunity, as sure as Dr. Oz’s latest tonic will strengthen other sorts of immunity. Shucks, if we keep it coming, we may never die! Alas, however, this run-straight-into-darkness strategy is, just like gobs of blueberries, completely ineffective at warding off trouble.

Perhaps, though, it is best that the big awful secret remains hidden from the public, out of Working Stiff and everywhere else. No one really wants to know just how excited a guy can get when he makes a difficult diagnosis, his thrill at being right, his satisfaction at seeing a rare disease even if it kills the person whose hand he shook warmly just a day or two ago. In this moment when transparency is all and seemingly every story must be told and every secret bared, it actually may be time to re-introduce the concept of opacity.