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Physicists have designed the world’s smallest refrigerator, small enough that it can’t hold any of your food. The fridge consists of three qubits–quantum particles that act as on-off switches. These quantum particles could be ions, atoms, or subatomic particles.

Other small systems have been created, but this is the first that doesn’t rely on external mechanisms, such as sophisticated lasers. “The whole guts of the fridge, it’s all accounted for and not hidden in some macroscopic object which is really doing the work,” [coauthor Noah] Linden says. [Science News]

Kitchen refrigerators work by shuttling heat away from one area (where you store your food) and dumping it somewhere else (the coils behind). This transfer isn’t news. Fans of thermodynamics have built devices to wick away heat from one source and dump it somewhere else since the nineteenth century. The device proposed in a paper to appear in Physical Review Letters uses the same basic technique but at a much smaller scale–on the size of three qubits, connected to two “baths,” one cold (or around room temperature) and one hot.

You could represent an excited qubit as a 1, and an unexcited qubit as a 0. The trio might start in a state of “101″  which means “excited unexcited excited” or “010″ which means “unexcited excited unexcited.” Since the three qubits are linked, the system could flip between the two setups.  You might think of the excited qubits passing their excitement, or transferring energy, to the unexcited qubits–until the excited qubits become unexcited and the unexcited qubits become excited. If they are all the same temperature, they can flip back and forth from 101 to 010 to 101… all the live long day.

But this equal flipping changes when you add the hot and cold baths:

The trick is to put the first two qubits in contact with a cold bath and the third one in contact with a hot bath. The higher temperature makes it more likely that the third qubit will be in its excited state—and thus that the trio will be in the (101) state instead of the (010) state. But that means the system is more likely to flip out of (101) and into (010) than the other way around. So on average the flipping takes the first qubit from its excited state to its ground state and draws energy out of the first qubit. After a flip, the qubits essentially reset by interacting with the baths, allowing the cycle to start again. [ScienceNOW]

The researchers say they can just leave the system be and it will continue drawing energy out of that first qubit as long as the hot bath remains hot. Besides serving as an interesting look at thermodynamics on a quantum scale, the researchers believe the setup, when built, may find use in quantum computing.

Though one possibility for actually constructing the very mini-fridge involves capturing ions to act as qubits, ScienceNOW reports, an even smaller hypothetical fridge uses a particle with three levels instead of two.

Linden and his team also propose an even smaller system, in which a single particle with three distinct levels of quantum information, called a qutrit, acts as the refrigerator. “We believe this is the smallest possible thing you can call a fridge,” Linden says. [Science News]

Though quantum theorists may now hold the title for smallest refrigerator, particle physicists’ Large Hadron Collider with its superfluid helium “cryogenic distribution system” can cool a 16 mile accelerator ring, arguably making the LHC the planet’s largest fridge.

Image: flickr /Tweek

Source: Quantum Fridge: The Quest to Build the World’s Smallest Refrigerator

The city of New Orleans’ defenses are certainly better than they were five years ago, when Hurricane Katrina breached the levees and flooded the city. With the five-year anniversary of that disaster upon us, however, the question that hangs in the air is: Would those refurbished barriers stand up to another Katrina, or something worse?

Better Barricades

In the last five years, the federal government has invested about $15 billion to revamp the New Orleans levee system.

This time, tougher foundation material like a mixture of construction clay and cement, is being used in the soil to hold structural sections of wall designed as an inverted T instead of their previous I-shape. The new design is considered stronger, allowing steel pillars to bracket each end into the ground. Total completion is expected in June 2011. [Christian Science Monitor]

The levee system stretches about 350 miles around the city, and its walls stand about 30 feet high (Katrina’s storm surge rose to about 28 feet).

Bigger Storms?

Gregory Gunter of the U.S. Army Corps of Engineers trumpets the new systems as a defense against the so-called “100-year storm”—a tempest so bad it has only a 1 percent chance of striking in a given year.

The system shouldn’t fail in a “400-year” Katrina-strength storm either, although Gunter says such a surge would probably flow over the barriers. This would lead to some flooding, but nothing like the scale of Katrina, which pushed over walls and breached levees. [New Scientist]

However, flood experts point out, the people who really know about keeping flood waters at bay—the Dutch—build their levees with a much larger investment, intending them to withstand a “10,000-year” event. In addition, because our hurricane records go back only so far, and because the past may not be an accurate picture of future storms, those year designations may be misleading anyway.

Paul Kemp, director of the National Audubon Society’s Louisiana Coastal Initiative in Baton Rouge, and former storm surge modeller, says the new designs presume that future storms will resemble past ones. He points out that climate change may increase hurricane strength. [New Scientist]

Don’t Forget the Wetlands

The Corps of Engineers has taken its share about abuse for Katrina failures (including by New Orleans resident Harry Shearer of The Simpsons and This Is Spinal Tap fame, whose new Katrina documentary is out now). The levees weren’t the only problem, though: New Orleans’ degraded wetlands put the city in added danger.

According to the Army Corps, all of the levees that failed during Katrina lacked wetland protection; the levees with a wetland buffer remained intact. Scientists have estimated that storm surge is diminished by one foot for every square-mile of wetland it travels through [National Geographic].

Now, groups like the Sierra Club are trying to revive the cypress ecosystem that once thrived in the shallow waters, and are doing so with a plan that actually requires pumping in partially treated sewage. With a high enough volume of biosolids—semi-treated sewage—they could add up to four feet of new material in which plants could take root.

The swamp has been killed primarily through saltwater intrusion from the various surrounding canals that connect the Mississippi River to the Gulf of Mexico. A pulse of freshwater sewage could make the site more suitable for wetland species. In return, those species would help filter and clean the effluent [National Geographic].

Unknown Toll

President Obama spoke at Xavier University of Louisiana in New Orleans yesterday to mark the Katrina anniversary, praising the growth of small business and announcing that the federal government was finally ready to dole out its promised $2 billion investment in the city school system. But one thing still remains unsettled: Just how many people we lost, and who they are.

The Houston Chronicle reports that about 500 of the 1,500 people in Louisiana’s recognized death toll remain unidentified. And that official count could be a lowball figure, some argue:

John Mutter, a Columbia University professor, has been gathering personal testimonials and public records of those killed in Katrina for an effort he calls Katrinalist. Mutter estimates the true death toll will top 3,500 if those killed by the storm and by its many after-effects are accurately tallied. And yet other counts put the toll at an estimated 1,800 [Houston Chronicle].

Image: Office of the President of the United States

Source: Five Years Later, Could New Orleans Withstand Another Major Hurricane?

rhaas writes “NASA’s Kepler spacecraft has discovered the first confirmed planetary system with more than one planet crossing in front of, or transiting, the same star. They found two planets almost the size of Saturn, and possibly a third, small, very hot planet with a radius about 1.5 times that of Earth.”

Source: Kepler Spacecraft Finds System With Multiple Planets Transiting the Star

The two newest planets spied by the Kepler space telescope are locked in a forever back-and-forth.

When Kepler’s scientists saw a star 2,000 light years away dim slightly, they knew there was the chance it was the telltale signature of a planet passing in front. But when the calculations were done and the confirmation came in, they found a surprise—what they’d seen was actually two stars transiting in front of the star.

NASA says it’s the first time they’ve ever caught such a sight, and today the scientists officially announced the finding with a study in Science. While other studies have found multiple planets around a single star–in fact, it happened earlier this week–those studies have used different planet-detection techniques like the wobble method.

The two worlds, both gas giants, do more than orbit the same star on the same plane, though. They push and pull each other in a motion that keeps the two exoplanets close to arithmetic celestial perfection. Kepler-9B, the larger, orbits the star in 19.24 days on average, the astronomers saw. Kepler-9c, the smaller, completes a revolution in an average of 38.91 days. But every time the scientists checked, 9b’s orbit was getting 4 minutes longer, while 9c’s shrank by 39 minutes.

That suggests the planets are in the midst of a gravitational push-pull that keeps the orbits close to a 2-to-1 ratio, in what’s known as a planetary resonance. In our own solar system, Pluto and Neptune are in a similar resonance (2-to-3), which is why little Pluto can’t be kicked out its orbit. The same thing applies to the Kepler-9 system [MSNBC].

While the ratio at the moment slightly exceeds 2 to 1, Kepler-9b’s growing orbital time and 9c’s shrinking one mean the system is moving back toward 2 to 1. Like a pendulum it will swing to a ratio just smaller than 2 to 1, and then swing back as the two planets’ gravities keep each other constantly in check.

Study leader Matthew Holman says that the larger, inner world has a mass about 80 times that of Earth. Its smaller counterpart tallies about 54 Earth masses.

“The variation in transit times depend upon the masses of the planet,” Holman told reporters in a news conference announcing the findings. “The larger the mass the larger the variations. These variations allows us to determine the mass of the objects and we can confirm that they are planets” [Universe Today].

There’s something else in the Kepler-9 system, too: a candidate for a small planet just about one and a half times the size of Earth. However, while the two large planets are now confirmed—bringing Kepler’s exoplanet count to seven—the possible super-Earth remains with the hundreds of candidates in Kepler’s files that must be confirmed through further studies.

Image: NASA/Ames/JPL-Caltech

Source: Astronomers Find 2 Giant Exoplanets Locked in an Endless Dance

In August 2006, Pluto received its official demotion to dwarf planet status, taking our solar system down to eight planets. In August 2010, exoplanet hunters say they’ve found a haul of new worlds around a single star; that alien solar system may have seven known planets, meaning the system could be more like our home system than any ever discovered. And one of those worlds could be the smallest exoplanet ever found, too.

The star these planets orbit is called HD 10180, and it lies 127 light years from here. Astronomers at the European Southern Observatory in Chile used a spectrograph called HARPS to track tiny variations in the starlight caused by the pull of the planets.

It found clear evidence for five giant planets similar in size to Uranus or Neptune in our own solar system. But there were also tantalising signs that two other planets are also present, one of which would be the smallest, or least-massive, yet found orbiting another star [Christian Science Monitor].

While those gas planets would be at least 13 times the size of the Earth, the small world—if it’s truly there—would contain less than one and a half Earth masses. But as astronomers have seen with many of the small exoplanets they’ve found, Earth-size doesn’t mean Earth-like when it comes to temperature, chemical composition, or anything else. The HARPS data suggests this roughly Earth-size planet is scaldingly close to the star: Its year is just more than one of our days.

And, as we saw last month when one of the scientists behind the planet-hunting Kepler mission got everyone excited over Earth-size planet “candidates,” it can take a long time to confirm the finding of smaller, rocky worlds. Astronomer Alan Boss agreed:

Boss noted that the method was “biased toward finding the big guys” because the greater the planet, the greater its gravity and the more it made its parent star wobble. But he said the discovery showed that finding smaller planets was still possible. “This field has gone from zero to close to 500 planets in just 15 years,” he said. “Fifteen years ago we did not know about the big guys. Earth-like planets are going to be quite commonplace” [AP].

Whether this star system has five or seven planets, it shows that astronomers are creeping closer to finding systems that look like ours. National Geographic reports that just 15 known systems have three planets or more, but that number might soon shoot upward. Next year the Kepler scientists are supposed to release their full data set from the telescope’s first batch of findings, including the Earth-sized candidates they’ve been holding back. And, on a more basic level, every year since the first exoplanet discovery, astronomers have spotted more of them than the year before.

As the planet count rises, we’ll probably see solar systems that resemble home on more sophisticated levels. HD 10180 might have about the same number of planets as our sun, but the system itself is markedly different: Those Neptune-sized gas planets orbit much closer than Neptune, and there doesn’t appear to be a Jupiter-sized giant in the group. The gravitational influence of a huge gas giant can especially influence the prospects for life:

Studies have shown that Jupiter, with its gassy enormity, has been acting as a sort of shield for Earth, gravitationally deflecting asteroids and comets that hold the potential to trigger mass extinctions [National Geographic].

So there’s no place quite like home… yet.

Image: ESO / Davide De Martin

Source: Homey-Looking Alien Star System May Host 7 Planets

eldavojohn writes “The European Southern Observatory has announced that with the aid of their 190 HARPS measurements they have found the solar system with the most planets yet. Furthermore they claim ‘This remarkable discovery also highlights the fact that we are now entering a new era in exoplanet research: the study of complex planetary systems and not just of individual planets. Studies of planetary motions in the new system reveal complex gravitational interactions between the planets and give us insights into the long-term evolution of the system.’ The star is HD 10180, located 127 light-years away in the southern constellation of Hydrus, that boasts at least five planets (with two more expected) that have the equivalent of our own Titius–Bode law (their orbits follow a regular pattern). Their survey of stars also helped reinforce the correlation between ‘between the mass of a planetary system and the mass and chemical content of its host star. All very massive planetary systems are found around massive and metal-rich stars, while the four lowest-mass systems are found around lower-mass and metal-poor stars.’ While we won’t be making a 127 light-year journey anytime soon, the list of candidates for systems of interest grows longer.”

Source: Richest Planetary System Discovered With 7 Planets

Bruce Schneier noted a story today over at his blog about a new Skeletal Identification System being developed at Wright State. Of course this is just another biometric detection system, but one that would be pretty tough to disguise.

Source: Skeletal Identification

cbraescu1 writes “I live in a city with a population in the millions (someplace in the Middle East; the country is not important), and I am mad as hell. The car traffic is going from bad to worse, and I’m sick of all the car accidents that keep happening (we have one of the biggest accident and mortality rates per km of road or per 1,000 vehicles). I just witnessed a car accident a few hours ago, and in the last few months I’ve given first aid at two other car accidents, all happening within 500 meters of each other. Today’s victims escaped alive, but the motorcycle driver who was responsible fled and the police weren’t equipped to catch him. There are laws, but not much willingness to enforce them, and no traffic lights at all. After speaking with some of my friends, we decided to take the issue into our own hands: build a traffic radar system able to capture a vehicle’s speed, install it at our own expense, and share the generated penalties with the city government (all subject of their approval, of course). We want to start on the main avenue (more than 15 km) and to ‘roll’ the income from the penalties into covering new streets (so that perpetrators will basically finance the system). We’re not rich and we will not ask for our money back. We just need to make the system start and we’re confident the penalty fees will cover its spread. So, I’m asking Slashdot: what would be a workable way to build such a system? It must withstand drivers claiming the system is cheating, high temperatures, high levels of humidity, and crappy electricity. Any suggestions would be appreciated. This is about technology saving lives — literally.”

Source: Building a Traffic Radar System To Catch Reckless Drivers?

aarondubrow writes “Researchers at MIT have created an experimental system for smart phones that allows engineers to leverage the power of supercomputers for instant computation and analysis. The team performed a series of expensive high-fidelity simulations on the Ranger supercomputer to generate a small “reduced model” which was transferred to a Google Android smart phone. They were then able to solve engineering and fluid flow problems on the phone and visualize the results interactively. The project proved the potential for reduced order methods to perform real-time and reliable simulations for complicated problems on handheld devices.”

Source: Supercomputing, There’s an App For That

eburnette writes “A former Sun/Oracle employee explains how developers created patents in an unofficial contest to see who could get the goofiest patent through the system. James Gosling said, ‘… we got sued, and lost. The penalty was huge. Nearly put us out of business. We survived, but to help protect us from future suits we went on a patenting binge. Even though we had a basic distaste for patents, the game is what it is, and patents are essential in modern corporations, if only as a defensive measure. There was even an unofficial competition to see who could get the goofiest patent through the system. My entry wasn’t nearly the goofiest.’ Now Oracle is using patents from the same folks as the basis for its lawsuit against Google.”

Source: Why Software Patents Are a Joke — Literally