Category Archives: quantum / physics

Scientists make quantum leap in developing faster computers

The researchers have created components that could one day be used to develop quantum computers – devices based on molecular scale technology instead of and which would be much faster than conventional computers.

The study, by scientists at the Universities of Manchester and Edinburgh and published in the journal Nature, was funded by the European Commission.

Scientists have achieved the breakthrough by combining with molecular machines that can shuttle between two locations without the use of external force. These manoeuvrable magnets could one day be used as the basic component in quantum computers.

Conventional computers work by storing information in the form of bits, which can represent information in binary code – either as zero or one.

Quantum computers will use quantum , or , which are far more sophisticated – they are capable of representing not only zero and one, but a range of values simultaneously. Their complexity will enable quantum computers to perform intricate calculations much more quickly than conventional computers.

Professor David Leigh, of the University of Edinburgh’s School of Chemistry, said: “This development brings super-fast, non-silicon based computing a step closer.


Most powerful ever quantum chip undergoing tests

QUANTUM computing for the masses could come a step closer if tests prove successful on a prototype chip designed to process more quantum data than any previous device.

Quantum computers have the potential to be vastly more powerful than conventional machines because they exploit the rules of quantum mechanics to perform many calculations in parallel. They are difficult to build, however, because quantum information is easily destroyed. The most powerful machines to date can cope with only a handful of quantum bits, or qubits, making them little more capable than a hand-held calculator.

In contrast, the prototype chip built by D-Wave Systems in Burnaby, British Columbia, Canada, is designed to handle 128 qubits of information. The data is stored in 128 superconducting niobium loops as either a clockwise or an anticlockwise current, representing a 0 or a 1, or as a qubit with both currents at the same time in a quantum superposition. When the information needs to be processed, the individual qubits are manipulated by a magnetic field. To make the entire chip superconduct so that the currents can flow indefinitely without dissipating heat, it is cooled to 0.01 °C above absolute zero.

Because superconducting circuits are relatively large, they are easier to manufacture than other types of quantum devices, which manipulate single electrons or photons and so need to be much smaller. “It can be built using standard semiconductor approaches,” says Geordie Rose, chief technology officer of D-Wave. In addition, the method of computation, called adiabatic computing, does not use logic gates, further simplifying the design.


Physicists Find Dark Matter, or Something Even More Strange

A new experiment may have found the first direct evidence of dark matter particles, a discovery that could begin to unravel one of the biggest mysteries in physics.

Theorists believe that dark matter, made up of of weakly-interacting massive particles, composes 23 percent of the universe, but no one has ever directly detected one of these WIMPs.

Now, physicists have announced they’ve spotted electrons with just about the amount of energy they would have expected to be made by a particular kind of WIMP entering the visible world.

John Wefel of Louisiana State University and colleagues report in Nature Wednesday that they could have detected “Kaluza-Klein” electron-positron pairs resulting from the annihilation of these WIMPS.

The KK particles are predicted by multiple-dimension theories of the universe and have long-been a leading candidate as the substance of dark matter. The new discovery then, if confirmed, would provide evidence that the fabric of space-time has many “compact” dimensions beyond the four that humans perceive.

“If the Kaluza–Klein annihilation explanation proves to be correct, this will necessitate a fuller investigation of such multidimensional spaces, with potentially important implications for our understanding of the Universe,” the authors conclude.


Quantum computers could excel in modeling chemical reactions

Quantum computers would likely outperform conventional computers in simulating chemical reactions involving more than four atoms, according to scientists at Harvard University, the Massachusetts Institute of Technology, and Haverford College. Such improved ability to model and predict complex chemical reactions could revolutionize drug design and materials science, among other fields.

Writing in the Proceedings of the National Academy of Sciences, the researchers describe “software” that could simulate chemical reactions on quantum computers, an ultra-modern technology that relies on quantum mechanical phenomena, such as entanglement, interference, and superposition. Quantum computing has been heralded for its potential to solve certain types of problems that are impossible for conventional computers to crack.

“There is a fundamental problem with simulating quantum systems — such as chemical reactions — on conventional computers,” says Alán Aspuru-Guzik, assistant professor of chemistry and chemical biology in Harvard’s Faculty of Arts and Sciences. “As the size of a system grows, the computational resources required to simulate it grow exponentially. For example, it might take one day to simulate a reaction involving 10 atoms, two days for 11 atoms, four days for 12 atoms, eight days for 13 atoms, and so on. Before long, this would exhaust the world’s computational power.”

Unlike a conventional computer, Aspuru-Guzik and his colleagues say, a quantum computer could complete the steps necessary to simulate a chemical reaction in a time that doesn’t increase exponentially with the reaction’s complexity.


Hawking: If we survive the next 200 years, we should be OK

Professor Stephen Hawking, one of the world’s great scientists, is looking to the stars to save the human race — but pessimism is overriding his natural optimism.

Hawking, in an exclusive CNN interview, said that if humans can survive the next 200 years and learn to live in space, then our future will be bright.

“I believe that the long-term future of the human race must be in space,” said Hawking, who is almost completely paralyzed by the illness ALS.

“It will be difficult enough to avoid disaster on planet Earth in the next 100 years, let alone next thousand, or million. The human race shouldn’t have all its eggs in one basket, or on one planet. Let’s hope we can avoid dropping the basket until we have spread the load.”

Hawking is one of the few scientists known to a wide audience outside academia thanks to his best-selling books, a guest spot on “The Simpsons” and an ability to clearly explain the complexities of theoretical physics.

He has 12 honorary degrees, was awarded the CBE in 1982 and since 1979 has been at Cambridge University’s Department of Applied Mathematics and Theoretical Physics, where he is Lucasian Professor of Mathematics — a post once held by Isaac Newton.

Speaking at Cambridge’s Centre for Mathematical Studies, he said: “I see great dangers for the human race. There have been a number of times in the past when its survival has been a question of touch and go. The Cuban missile crisis in 1963 was one of these. Video Watch the interview in full »

“The frequency of such occasions is likely to increase in the future. We shall need great care and judgment to negotiate them all successfully.

“But I’m an optimist. If we can avoid disaster for the next two centuries, our species should be safe, as we spread into space.”


World first for sending data using quantum cryptography

For the first time the transmission of data secured by quantum cryptography is demonstrated within a commercial telecommunications network. 41 partners from 12 European countries, including academics from the University of Bristol, have worked on realising this quantum cryptographic network since April 2004.

Today [Wednesday 8 October] the first commercial communication network using unbreakable encryption based on quantum cryptography is demonstrated in Vienna, Austria. In particular the encryption utilises keys that are generated and distributed by means of quantum cryptographic technologies. Potential users of this network, such as government agencies, financial institutions or companies with distributed subsidiaries, can encrypt their confidential communication with the highest level of security using the quantum cryptographically generated keys.

The network consists of six nodes and eight intermediary links with distances between 6km and 82km (seven links utilising commercial standard telecommunication optical fibres and one “free-space”-link along a line of sight between two telescopes). The links employ altogether six different quantum cryptographic technologies for key generation which are integrated into the network over standardised interfaces.

The network is installed in a standard optical fibre communication ring provided by SECOQC partners, Siemens AG Österreich in Vienna. Five subsidiaries of Siemens are connected to the network. The operation of the quantum cryptographic network will be visualised on a screen at the Siemens Forum in Vienna and streamed live over the Internet. The network-wide key generation and distribution will be demonstrated, the different functionalities of the network itself will be presented as well as utilisation of the keys for standard communication applications. A voice-over-iptelephone-application will be secured by the information-theoretically secure “one-time-pad-encryption“ while videoconferencing will be protected by symmetrical AES-encryption with frequent key changes. A low-cost key distributor, with the potential of extending the quantum cryptographic network to the consumer, will also be shown.


Star Trek warp drive is a possibility, say scientists

Two physicists have boldly gone where no reputable scientists should go and devised a new scheme to travel faster than the speed of light.

The advance could mean that Star Trek fantasies of interstellar civilisations and voyages powered by warp drive are now no longer the exclusive domain of science fiction writers.

In the long running television series created by Gene Roddenberry, the warp drive was invented by Zefram Cochrane, who began his epic project in 2053 in Bozeman, Montana.

Now Dr Gerald Cleaver, associate professor of physics at Baylor, and Richard Obousy have come up with a new twist on an existing idea to produce a warp drive that they believe can travel faster than the speed of light, without breaking the laws of physics.

In their scheme, in the Journal of the British Interplanetary Society, a starship could “warp” space so that it shrinks ahead of the vessel and expands behind it.

By pushing the departure point many light years backwards while simultaneously bringing distant stars and other destinations closer, the warp drive effectively transports the starship from place to place at faster-than-light speeds.


Quantum computing breakthrough

In a Nature Physics journal paper currently online, the researchers describe how they have created a new, hybrid molecule in which its quantum state can be intentionally manipulated – a required step in the building of quantum computers.

“Up to now large-scale quantum computing has been a dream,” says Gerhard Klimeck, professor of electrical and computer engineering at Purdue University and associate director for technology for the national Network for Computational Nanotechnology.

“This development may not bring us a quantum computer 10 years faster, but our dreams about these machines are now more realistic.”

The workings of traditional computers haven’t changed since they were room-sized behemoths 50 years ago; they still use bits of information, 1s and 0s, to store and process information. Quantum computers would harness the strange behaviours found in quantum physics to create computers that would carry information using quantum bits, or qubits. Computers would be able to process exponentially more information.

If a traditional computer were given the task of looking up a person’s phone number in a telephone book, it would look at each name in order until it found the right number. Computers can do this much faster than people, but it is still a sequential task. A quantum computer, however, could look at all of the names in the telephone book simultaneously.

Quantum computers also could take advantage of the bizarre behaviours of quantum mechanics – some of which are counterintuitive even to physicists – in ways that are hard to fathom. For example, two quantum computers could, in concept, communicate instantaneously across any distance imaginable, even across solar systems.


Astronomers discover largest dark matter structures, spanning 270M light-years

Astronomers discover largest dark matter structures, spanning 270M light-years

A University of British Columbia astronomer with an international team has discovered the largest structures of dark matter ever seen. Measuring 270 million light-years across, these dark matter structures criss-cross the night sky, each spanning an area that is eight times larger than the full moon.

“The results are a major leap forward since the presence of a cosmic dark matter web that extends over such large distances has never been observed before,” says Ludovic Van Waerbeke, an assistant professor in the Dept. of Physics and Astronomy.

To glimpse the unseen structures, the team of French and Canadian scientists “X-rayed” the dark matter, an invisible web that makes up more than 80 per cent of the mass of the universe.

The team used a recently developed technique called “weak gravitational lensing,” which is similar to taking an X-ray of the body to reveal the underlying skeleton. The study relied on data gathered from the world’s largest digital camera.

“This new knowledge is crucial for us to understand the history and evolution of the cosmos,” says Van Waerbeke. “Such a tool will also enable us to glimpse a little more of the nature of dark matter.”

Google sponsors new race to the moon

Google sponsors new race to the moon

More than three decades after the last Apollo astronauts roamed the lunar surface, disparate universities, open-source engineers and quixotic aerospace start-ups are planning to start their own robotic missions to the Earth’s barren cousin.

The return to the moon is part of the Google Lunar X Prize, a competition sponsored by Google with $30 million in prizes for the first two teams to land a robotic rover on the moon and send images and other data back home.

At Google’s headquarters here Thursday, 10 teams from five countries announced their intention to participate in the competition.

They include a team led by William Whitaker, a professor at Carnegie Mellon University and a renowned roboticist; an affiliation of four universities and two major aerospace companies in Italy; and one group comprised of a loose association of engineers coordinating their efforts online.

At the event, the new lunar explorers shared some high-minded goals, like reigniting moon exploration and jump-starting an age of space commerce. “This is about developing a new generation of technology that is cheaper, can be used more often and will enable a new wave of explorers,” said Peter Diamandis, chairman of the X Prize Foundation.