Skip to main content

Home/ Indie Nation/ Group items tagged physics

Rss Feed Group items tagged

John Lemke

Scientists May Have Decoded One of the Secrets to Superconductors | Science | WIRED - 0 views

  • “In the same way that a laser is a hell of a lot more powerful than a light bulb, room-temperature superconductivity would completely change how you transport electricity and enable new ways of using electricity,” said Louis Taillefer, a professor of physics at the University of Sherbrooke in Quebec.
  • ripples of electrons inside the superconductors that are called charge density waves. The fine-grained structure of the waves, reported in two new papers by independent groups of researchers, suggests that they may be driven by the same force as superconductivity. Davis and his colleagues directly visualized the waves in a study posted online in April, corroborating indirect evidence reported in February by a team led by Riccardo Comin, a postdoctoral fellow at the University of Toronto.
  • Taken together, the various findings are at last starting to build a comprehensive picture of the physics behind high-temperature superconductivity. “This is the first time I feel like we’re making real progress,” said Andrea Damascelli, a professor of physics at the University of British Columbia who led two recent studies on charge density waves. “A lot of different observations which have been made over decades did not make sense with each other, and now they do.”
  • ...4 more annotations...
  • The community remained divided until 2012, when two groups using a technique called resonant X-ray scattering managed to detect charge density waves deep inside cuprates, cementing the importance of the waves. As the groups published their findings in Science and Nature Physics, two new collaborations formed, one led by Damascelli and the other by Ali Yazdani of Princeton University, with plans to characterize the waves even more thoroughly. Finishing in a dead heat, the rival groups’ independent studies appeared together in Science in January 2014. They confirmed that charge density waves are a ubiquitous phenomenon in cuprates and that they strenuously oppose superconductivity, prevailing as the temperature rises.
  • y applying Sachdev’s algorithm to a new round of data, Davis and his group mapped out the structure of the charge density waves, showing that the d-wave distribution of electrons was, indeed, their source.
  • The waves’ structure is particularly suggestive, researchers say, because superconducting pairs of electrons also have a d-wave configuration. It’s as if both arrangements of electrons were cast from the same mold. “Until a few months ago my thought was, OK, you have charge density waves, who cares? What’s the relevance to the high-temperature superconductivity?” Damascelli said. “This tells me these phenomena feed off the same interaction.”
  • In short, antiferromagnetism could generate the d-wave patterns of both superconductivity and its rival, charge density waves.
John Lemke

'Solid' light could compute previously unsolvable problems - Princeton Engine... - 0 views

  • The researchers are not shining light through crystal – they are transforming light into crystal. As part of an effort to develop exotic materials such as room-temperature superconductors, the researchers have locked together photons, the basic element of light, so that they become fixed in place.
  • The results raise intriguing possibilities for a variety of future materials. But the researchers also intend to use the method to address questions about the fundamental study of matter, a field called condensed matter physics.
  • To build their machine, the researchers created a structure made of superconducting materials that contains 100 billion atoms engineered to act as a single "artificial atom." They placed the artificial atom close to a superconducting wire containing photons. By the rules of quantum mechanics, the photons on the wire inherit some of the properties of the artificial atom – in a sense linking them. Normally photons do not interact with each other, but in this system the researchers are able to create new behavior in which the photons begin to interact in some ways like particles. "We have used this blending together of the photons and the atom to artificially devise strong interactions among the photons," said Darius Sadri, a postdoctoral researcher and one of the authors. "These interactions then lead to completely new collective behavior for light – akin to the phases of matter, like liquids and crystals, studied in condensed matter physics."
John Lemke

NSA reportedly intercepting laptops purchased online to install spy malware | The Verge - 0 views

  • According to a new report from Der Spiegel based on internal NSA documents, the signals intelligence agency's elite hacking unit (TAO) is able to conduct sophisticated wiretaps in ways that make Hollywood fantasy look more like reality. The report indicates that the NSA, in collaboration with the CIA and FBI, routinely and secretly intercepts shipping deliveries for laptops or other computer accessories in order to implant bugs before they reach their destinations. According to Der Spiegel, the NSA's TAO group is able to divert shipping deliveries to its own "secret workshops" in a method called interdiction, where agents load malware onto the electronics or install malicious hardware that can give US intelligence agencies remote access. While the report does not indicate the scope of the program, or who the NSA is targeting with such wiretaps, it's a unique look at the agency's collaborative efforts with the broader intelligence community to gain hard access to communications equipment. One of the products the NSA appears to use to compromise target electronics is codenamed COTTONMOUTH, and has been available since 2009; it's a USB "hardware implant" that secretly provides the NSA with remote access to the compromised machine.
  • The Der Spiegel report, which gives a broad look at TAO operations, also highlights the NSA's cooperation with other intelligence agencies to conduct Hollywood-style raids. Unlike most of the NSA's operations which allow for remote access to targets, Der Spiegel notes that the TAO's programs often require physical access to targets. To gain physical access, the NSA reportedly works with the CIA and FBI on sensitive missions that sometimes include flying NSA agents on FBI jets to plant wiretaps. "This gets them to their destination at the right time and can help them to disappear again undetected after even as little as a half hour's work," the report notes.
  •  
    While the scope or the targets are reportedly not known, the article also does not mention anything about a search warrant. This is what happens when the government feels they are above the law.
John Lemke

Roxxxy the US$7,000 companion/sex robot (NSFW) - 0 views

  •  
    When it comes to technology, the sex industry is no laggard, and as robots become more human-like in their appearance and abilities, US-based company TrueCompany is poised to launch Roxxxy - the world's first sex robot - that has many more capabilities than your average sex doll. Apart from having better defined physical features than previous dolls, Roxxxy has been programmed with her own personality and her manufacturers say she can listen, talk, carry on a conversation, feel your touch and respond to it, as well as move her private areas inside when she is being "utilized" to deliver an unforgettable erotic experience. There are even plans for a male version - Rocky the Robot.
John Lemke

BGU Students Develop Thought-Controlled, Hands-Free Computer For The Disabled - 0 views

  •  
    BGU software engineering students have developed innovative technology that could enable people to operate a computer without using a keyboard or mouse - only their brainwaves. While there have been previous attempts to develop devices to read brainwaves and operate specific programs, they were cumbersome and not feasible outside of a laboratory setting. The BGU technology features a helmet equipped with 14 EEG connect points that sense brain activity. According to Dr. Rami Puzis, "The technology is designed to assist those who are physically disabled who might otherwise be unable to manipulate a computer mouse or keyboard." The student team, Ori Ossmy, Ofir Tam and Ariel Rozen, developed the prototype application for their bachelor's degree project under supervision at BGU by Prof. Mark Last, Dr. Rami Puzis, Prof. Yuval Elovich and Dr. Lior Rokah. As part of a recent demonstration, a student composed and sent a hands-free e-mail using only thought combined with the adaptive hardware. The students and BGU team plan to continue research working with the disabled.
John Lemke

New Theory Suggests Parallel Universes Interact With And Affect Our Own Universe | IFLS... - 0 views

  • This new theory suggests that all of these infinite multiple worlds overlap and occupy the same region of time and space simultaneously, just like a quantum state. 
  • Under this new interpretation, some worlds in parallel universes would be nearly identical. In others, the “Butterfly Effect” is responsible for completely different outcomes. Each universe is equally real; it isn’t that one universe is the truth while others are bizarre copies or lesser in any way. Wiseman also believes that the quantum forces responsible for driving this shared existence are also responsible for causing quantum interactions between the worlds.
John Lemke

Voyager 1 spots new region at the edge of the Solar System | Ars Technica - 0 views

  • The researchers suspect they've reached a region of the solar-interstellar boundary that nobody had predicted. In this area, the magnetic field lines of the Sun link up with those of the interstellar field. Scientists are calling this linkage a "highway" for particles to travel along. It lets solar wind particles escape more readily, causing the drop in their intensity. And it opens the door for low-energy cosmic rays to slip in to our Solar System, which is why Voyager 1 is seeing so many of them. According the researchers at the press conference that announced these results, most steady-state models of the Solar System failed to predict anything like this. A few models did have a feature like this, but it was only a transient one that appeared at certain times of the solar cycle.
John Lemke

Rent-to-own PCs surreptitiously captured users' most intimate moments | Ars Technica - 0 views

  • The software, known as PC Rental Agent, was developed by Pennsylvania-based DesignerWare. It was licensed by more than 1,617 rent-to-own stores in the US, Canada, and Australia to report the physical location of rented PCs. A feature known as Detective Mode also allowed licensees to surreptitiously monitor the activities of computer users. Managers of rent-to-own stores could use the feature to turn on webcams so anyone in front of the machine would secretly be recorded. Managers could also use the software to log keystrokes and take screen captures.
  • In some cases, webcam activations captured images of children, individuals not fully clothed, and people engaged in sexual activities, the complaint alleged. Rental agreements never disclosed the information that was collected, FTC lawyers said.
  • PC Rental Agent also had the capability to display fake registration pages for Microsoft Windows, Internet Explorer, Microsoft Office, and Yahoo Messenger. When customers entered their names, addresses, and other personal information in the forms, the data was sent to DesignerWare servers and then e-mailed to the rent-to-own licensees.
John Lemke

FBI surveillance malware in bomb threat case tests constitutional limits | Ars Technica - 0 views

  • The FBI has an elite hacker team that creates customized malware to identify or monitor high-value suspects who are adept at covering their tracks online, according to a published report.
  • as the capability to remotely activate video cameras and report users' geographic locations—is pushing the boundaries of constitutional limits on searches and seizures
  • Critics compare it to a physical search that indiscriminately seizes the entire contents of a home, rather than just those items linked to a suspected crime. Former US officials said the FBI uses the technique sparingly, in part to prevent it from being widely known.
  • ...1 more annotation...
  • "We have transitioned into a world where law enforcement is hacking into people’s computers, and we have never had public debate,” Christopher Soghoian, principal technologist for the American Civil Liberties Union, told The Washington Post, speaking of the case against Mo. "Judges are having to make up these powers as they go along."
John Lemke

Colliding Atmospheres: Mars vs Comet Siding Spring - NASA Science - 0 views

  • "We hope to witness two atmospheres colliding," explains David Brain of the University of Colorado's Laboratory for Atmospheric and Space Physics (LASP).  "This is a once in a lifetime event!"
  • Everyone knows that planets have atmospheres.  Lesser known is that comets do, too.  The atmosphere of a comet, called its "coma," is made of gas and dust that spew out of the sun-warmed nucleus.  The atmosphere of a typical comet is wider than Jupiter.
  • The timing could scarcely be better.  Just last year, NASA launched a spacecraft named MAVEN to study the upper atmosphere of Mars, and it will be arriving in Sept. 2014 barely a month before the comet. MAVEN is on a mission to solve a longstanding mystery: What happened to the atmosphere of Mars?  Billions of years ago, Mars had a substantial atmosphere that blanketed the planet, keeping Mars warm and sustaining liquid water on its surface. Today, only a wispy shroud of CO2 remains, and the planet below is colder and dryer than any desert on Earth. Theories for this planetary catastrophe center on erosion of the atmosphere by solar wind.
  • ...1 more annotation...
  • the comet could spark Martian auroras.
John Lemke

Elusive particle that is its own antiparticle observed -- ScienceDaily - 0 views

  • Using a two-story-tall microscope floating in an ultralow-vibration lab at Princeton's Jadwin Hall, the scientists captured a glowing image of a particle known as a "Majorana fermion" perched at the end of an atomically thin wire -- just where it had been predicted to be after decades of study and calculation dating back to the 1930s.
  • The hunt for the Majorana fermion began in the earliest days of quantum theory when physicists first realized that their equations implied the existence of "antimatter" counterparts to commonly known particles such as electrons. In 1937, Italian physicist Ettore Majorana predicted that a single, stable particle could be both matter and antimatter. Although many forms of antimatter have since been observed, the Majorana combination remained elusive.
  • Despite combining qualities usually thought to annihilate each other -- matter and antimatter -- the Majorana fermion is surprisingly stable; rather than being destructive, the conflicting properties render the particle neutral so that it interacts very weakly with its environment. This aloofness has spurred scientists to search for ways to engineer the Majorana into materials, which could provide a much more stable way of encoding quantum information, and thus a new basis for quantum computing.
John Lemke

Earth's Impending Magnetic Flip - Scientific American - 0 views

  • The European Space Agency's satellite array dubbed “Swarm” revealed that Earth's magnetic field is weakening 10 times faster than previously thought, decreasing in strength about 5 percent a decade rather than 5 percent a century. A weakening magnetic field may indicate an impending reversal, which scientists predict could begin in less than 2,000 years. Magnetic north itself appears to be moving toward Siberia.
  • There is a good chance the weakening magnetic field that the Swarm satellites observed will not lead to a full flip. Indeed, Glatzmaier notes that there have been several false starts over geologic history. The intensity of Earth's magnetic field, though waning, now equals its average strength over millions of years. The field would need to weaken at its current rate for around 2,000 years before the reversal process actually begins.
  • It is hard to know how a geomagnetic reversal would impact our modern-day civilization, but it is unlikely to spell disaster. Although the field provides essential protection from the sun's powerful radiation, fossil records reveal no mass extinctions or increased radiation damage during past reversals. A flip could possibly interfere with power grids and communications systems—external magnetic field disturbances have burned out transformers and caused blackouts in the past. But Glatzmaier is not worried. “A thousand years from now we probably won't have power lines,” he says. “We'll have advanced so much that we'll almost certainly have the technology to cope with a magnetic-field reversal.”
    • John Lemke
       
      Likely not the end of the world for past reversals have not show evidence of mass extinctions.
John Lemke

Physicist/musician's CD comes with a Petri dish and scientific paper - Boing Boing - 0 views

  •  
    A micrograph of stained penicillin is printed onto the CDs, which are presented in an attractive Petri Dish setting. The album sleeve notes come in the form of a 20-page scientific paper, telling you all you could ever wish to know about the origins, methods and results of this art/science endeavour, as well as full lyrics and some scientific background to explain the songs.
John Lemke

Cambridge team breaks superconductor world record | University of Cambridge - 0 views

  • three tonnes of force inside a golf ball-sized sample of material that is normally as brittle as fine china.
  • Superconductors are materials that carry electrical current with little or no resistance when cooled below a certain temperature. While conventional superconductors need to be cooled close to absolute zero (zero degrees on the Kelvin scale, or –273 °C) before they superconduct, high temperature superconductors do so above the boiling point of liquid nitrogen (–196 °C), which makes them relatively easy to cool and cheaper to operate.
  • Superconductors are currently used in scientific and medical applications, such as MRI scanners, and in the future could be used to protect the national grid and increase energy efficiency, due to the amount of electrical current they can carry without losing energy.
1 - 16 of 16
Showing 20 items per page