Last August, astronomers working on the analysis of data being acquired by NASA’s WMAP (Wilkinson Microwave Anisotropy Probe) satellite announced that they found a huge void in the universe. A void is a region of space that has much less material (stars, nebulae, dust and other material) than the average. Since our universe is relatively heterogeneous, empty spaces are not rare, but in this case the enormous magnitude of the hole is way outside the expected range. The hole found in the constellation of Eridanus is about a billion light years across, which is roughly 10,000 times as large as our galaxy or 400 times the distance to Andromeda, the closest “large” galaxy.

The dimension of the hole is so big that at first glance, it results impossible to explain under the current cosmological theories, although scientists put forward some explanations based on certain theoretical models that might predict the existence of “giant knots” in space known as topological defects.

However, University of North Carolina at Chapel Hill physics Professor Laura Mersini-Houghton made a staggering claim. She says, “Standard cosmology cannot explain such a giant cosmic hole” and goes further with the ground-breaking hypothesis that the huge void is “… the unmistakable imprint of another universe beyond the edge of our own“.

The idea of alternative, or parallel universes has been around for quite a while and has provided considerable inspiration for Sci-Fi literature and sparked endless philosophical debate, but although begin seriously considered within the scientific realm it never crossed the limits of speculative of purely theoretical grounds. Perhaps until now. If Mersini-Houghton is right, Eridanus’ giant hole would be the first experimental evidence for the existence of another universe. The implications of this possibility are obviously of huge importance for everybody, but it also has further relevance for the astrophysics community as it would bring support for the hotly debated string theory and other central debates.

But Mersini-Houghton and colleagues’ theory of entangled universes make testable predictions, providing the opportunity to confirm or refute the claim as more data arrive to the astronomers’ computers. Her model predicts the existence of two voids rather than one, one in each hemisphere of our universe. The one that has been found by WMAP’s data lies in the Northern hemisphere. They expect new data will show a second similar void in the Southern side. This and other cutting-edge experimental projects testing Mersini-Houghton’s ideas will tell us whether a new era in cosmological thinking has indeed arrived.

Here’s new NASA satellite video showing the astounding loss of Arctic sea ice.

The 2007 Arctic summer sea ice has reached the lowest extent of perennial ice cover on record - nearly 25% less than the previous low set in 2005.

The area of the perennial ice has been steadily decreasing since the satellite record began in 1979, at a rate of about 10% per decade. But the 2007 minimum, reached on September 14, is far below the previous record made in 2005 and is about 38% lower than the climatological average. Such a dramatic loss has implications for ecology, climate and industry.

Craig Venter, a DNA researcher that had a part in deciphering the human genome, has stuck together 580,000 base pairs of genetic code to create an entirely new and alien chromosome. Based around the Mycoplasma genitalium bacterium (pictured in all its primordial glory), the new chromosome is then implanted into a living cell and renamed as Mycoplasma laboratorium - don’t you just love science jokes? The new “life form” is reliant on the host cell for replication and metabolism so it’s not exactly entirely synthetic, but as the DNA is different, it is effectively an artificial form of life. Sounds like the human race’s really doomed now: ultimately, all we’re doing is setting the robots up with a tag team.

A novel device, developed by a team led by University at Buffalo engineers, simply and conveniently traps, detects and manipulates the single spin of an electron, overcoming some major obstacles that have prevented progress toward spintronics and spin-based quantum computing.

Published online this week in Physical Review Letters, the research paper brings closer to reality electronic devices based on the use of single spins and their promise of low-power/high-performance computing.

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“The task of manipulating the spin of single electrons is a hugely daunting technological challenge that has the potential, if overcome, to open up new paradigms of nanoelectronics,” said Jonathan P. Bird, Ph.D., professor of electrical engineering in the UB School of Engineering and Applied Sciences and principal investigator on the project.

“In this paper, we demonstrate a novel approach that allows us to easily trap, manipulate and detect single-electron spins, in a scheme that has the potential to be scaled up in the future into dense, integrated circuits.”

While several groups have recently reported the trapping of a single spin, they all have done so using quantum dots, nanoscale semiconductors that can only demonstrate spin trapping in extremely cold temperatures, below 1 degree Kelvin.

The cooling of devices or computers to that temperature is not routinely achievable, Bird said, and it makes systems far more sensitive to interference.

The UB group, by contrast, has trapped and detected spin at temperatures of about 20 degrees Kelvin, a level that Bird says should allow for the development of a viable technology, based on this approach.

In addition, the system they developed requires relatively few logic gates, the components in semiconductors that control electron flow, making scalability to complex integrated circuits very feasible.

The UB researchers achieved success through their innovative use of quantum point contacts: narrow, nanoscale constrictions that control the flow of electrical charge between two conducting regions of a semiconductor.

“It was recently predicted that it should be possible to use these constrictions to trap single spins,” said Bird. “In this paper, we provide evidence that such trapping can, indeed, be achieved with quantum point contacts and that it may also be manipulated electrically.”

The system they developed steers the electrical current in a semiconductor by selectively applying voltage to metallic gates that are fabricated on its surface.

These gates have a nanoscale gap between them, Bird explained, and it is in this gap where the quantum point contact forms when voltage is applied to them.

By varying the voltage applied to the gates, the width of this constriction can be squeezed continuously, until it eventually closes completely, he said.

“As we increase the charge on the gates, this begins to close that gap,” explained Bird, “allowing fewer and fewer electrons to pass through until eventually they all stop going through. As we squeeze off the channel, just before the gap closes completely, we can detect the trapping of the last electron in the channel and its spin.”

The trapping of spin in that instant is detected as a change in the electrical current flowing through the other half of the device, he explained.

“One region of the device is sensitive to what happens in the other region,” he said.

Now that the UB researchers have trapped and detected single spin, the next step is to work on trapping and detecting two or more spins that can communicate with each other, a prerequisite for spintronics and quantum computing. 

Physicists at the National Institute of Standards and Technology have transferred information between two “artificial atoms” by way of electronic vibrations on a microfabricated aluminum cable, demonstrating a new component for potential ultra-powerful quantum computers of the future. The setup resembles a miniature version of a cable-television transmission line, but with some powerful added features, including superconducting circuits with zero electrical resistance, and multi-tasking data bits that obey the unusual rules of quantum physics.

The resonant cable might someday be used in quantum computers, which would rely on quantum behavior to carry out certain functions, such as code-breaking and database searches, exponentially faster than today’s most powerful computers. Moreover, the superconducting components in the NIST demonstration offer the possibility of being easier to manufacture and scale up to a practical size than many competing candidates, such as individual atoms, for storing and transporting data in quantum computers.

Unlike traditional electronic devices, which store information in the form of digital bits that each possess a value of either 0 or 1, each superconducting circuit acts as a quantum bit, or qubit, which can hold values of 0 and 1 at the same time. Qubits in this “superposition” of both values may allow many more calculations to be performed simultaneously than is possible with traditional digital bits, offering the possibility of faster and more powerful computing devices. The resonant section of cable shuttling the information between the two superconducting circuits is known to engineers as a “quantum bus,” and it could transport data between two or more qubits.

The NIST work is featured on the cover of the Sept. 27 issue of Nature. The scientists encoded information in one qubit, transferred this information as microwave energy to the resonant section of cable for a short storage time of 10 nanoseconds, and then successfully shuttled the information to a second qubit.

“We tested a new element for quantum information systems,” says NIST physicist Ray Simmonds. “It’s really significant because it means we can couple more qubits together and transfer information between them easily using one simple element.”

The NIST work, together with another letter in the same issue of Nature by a Yale University group, is the first demonstration of a superconducting quantum bus. Whereas the NIST scientists used the bus to store and transfer information between independent qubits, the Yale group used it to enable an interaction of two qubits, creating a combined superposition state. These three actions, demonstrated collectively by the two groups, are essential for performing the basic functions needed in a superconductor-based quantum information processor of the future.

In addition to storing and transferring information, NIST’s resonant cable also offers a means of “refreshing” superconducting qubits, which normally can maintain the same delicate quantum state for only half a microsecond. Disturbances such as electric or magnetic noise in the circuit can rapidly destroy a qubit’s superposition state.

With design improvements, the NIST technology might be used to repeatedly refresh the data and extend qubit lifetime more than 100-fold, sufficient to create a viable short-term quantum computer memory, Simmonds says. NIST’s resonant cable might also be used to transfer quantum information between matter and light — microwave energy is a low-frequency form of light — and thus link quantum computers to ultra-secure quantum communications systems.

If they can be built, quantum computers — harnessing the unusual rules of quantum mechanics, the principles governing nature’s smallest particles — might be used for applications such as fast and efficient code breaking, optimizing complex systems such as airline schedules, making counterfeit-proof money, and solving complex mathematical problems. Quantum information technology in general allows for custom-designed systems for fundamental tests of quantum physics and as-yet-unknown futuristic applications.

A superconducting qubit is about the width of a human hair. NIST researchers fabricate two qubits on a sapphire microchip, which sits in a shielded box about 8 cubic millimeters in size. The resonant section of cable is 7 millimeters long, similar to the coaxial wiring used in cable television but much thinner and flatter, zig-zagging around the 1.1 mm space between the two qubits. Like a guitar string, the resonant cable can be stimulated so that it hums or “resonates” at a particular tone or frequency in the microwave range. Quantum information is stored as energy in the form of microwave particles or photons.