Particles known as baryons show their first hints of antimatter-matter discrepancies.
Category: particle physics – Page 598
Most people will be familiar with Moore’s Law which states that the number of transistors it’s possible to get on a microprocessor doubles every 18 months. If this holds true it means that some time in the 2020s we’ll be measuring these circuits on an atomic scale.
You might think that that’s where everything comes to a juddering halt. But the next step from this is the creation of quantum computers which use the properties of atoms and molecules to perform processing and memory tasks.
If this all sounds a bit sci-fi, it’s because practical quantum computers are still some way in the future. However, scientists have already succeeded in building basic quantum computers that can perform certain calculations. And when practical quantum computing does arrive it has the potential to bring about a change as great as that delivered by the microchip.
In Brief.
Researchers have published a paper demonstrating how they were able to create the first fully programmable and reprogrammable quantum computer in the world. Other quantum computers in existence at the moment can only run one type of operation.
While several other teams and companies, including computer technology giant IBM, are in on the race towards quantum computing, all the quantum computers presented thus far can only run one type of operation—which is ironic, seeing as quantum computers can theoretically run more operations than there are atoms in the universe.
Machines enrich and enhance our lives, whether it’s the smartphones that allow us to stay connected or the supercomputers that solve our toughest computational problems. Imagine how much more productive and innovative our world will be when computers become infinitely more powerful. Indeed, the growing field of quantum computing may make our current technological capacities look feeble and primitive in comparison. It could even transform the workings of the human brain and revolutionize how we think in ways we can’t begin to imagine.
Today, computers operate at the most basic level by manipulating two states: a zero or a one. In contrast, quantum computers are not limited to two states, but can encode information in multiple states that exist in superposition, also known as quantum bits or qubits.
In other words, this technology takes advantage of one of the most fascinating properties of the quantum world: the ability of subatomic particles to exist in more than one state at any given time. Consequently, a quantum computer can perform many calculations at the same time, whereas a traditional Turing machine can only perform a single calculation at once. Such quantum machines will be millions of times more powerful than our most powerful current computers.
If the 1967 film “The Graduate” were remade today, Mr. McGuire’s famous advice to young Benjamin Braddock would probably be updated to “Plastics … with nanoparticles.” These days, the mechanical, electrical and durability properties of polymers—the class of materials that includes plastics—are often enhanced by adding miniature particles (smaller than 100 nanometers or billionths of a meter) made of elements such as silicon or silver. But could those nanoparticles be released into the environment after the polymers are exposed to years of sun and water—and if so, what might be the health and ecological consequences?
In a recently published paper, researchers from the National Institute of Standards and Technology (NIST) describe how they subjected a commercial nanoparticle-infused coating to NIST-developed methods for accelerating the effects of weathering from ultraviolet (UV) radiation and simulated washings of rainwater. Their results indicate that humidity and exposure time are contributing factors for nanoparticle release, findings that may be useful in designing future studies to determine potential impacts.
In their recent experiment, the researchers exposed multiple samples of a commercially available polyurethane coating containing silicon dioxide nanoparticles to intense UV radiation for 100 days inside the NIST SPHERE (Simulated Photodegradation via High-Energy Radiant Exposure), a hollow, 2-meter (7-foot) diameter black aluminum chamber lined with highly UV reflective material that bears a casual resemblance to the Death Star in the film “Star Wars.” For this study, one day in the SPHERE was equivalent to 10 to 15 days outdoors. All samples were weathered at a constant temperature of 50 degrees Celsius (122 degrees Fahrenheit) with one group done in extremely dry conditions (approximately 0 percent humidity) and the other in humid conditions (75 percent humidity).
“It’s clear that the light is trapped — there are photons circulating around the atoms,” Everett says. “The atoms absorbed some of the trapped light, but a substantial proportion of the photons were frozen inside the atomic cloud.”
Co-researcher Geoff Campbell from ANU explained that while photons commonly pass by each other at the speed of light without any interactions, atoms interact with each other more freely.
“Corralling a crowd of photons in a cloud of ultra-cold atoms creates more opportunities for them to interact,” Campbell says.
Remember that scene in “The Force Awakens” where the dark side warrior Kylo Ren stops a laser blast in mid-air? In a Canberra laboratory, physicists have managed a feat almost as magical: they froze the movement of light in a cloud of ultracold atoms. This discovery could help bring optical quantum computers from the realms of sci-fi to reality.
The experiment, published in a paper this week, was inspired by a computer stimulation run by lead researcher Jesse Everett from the Australian National University. The researchers used a vaporized cloud of ultracold rubidium atoms to create a light trap, into which they shone infrared lasers. The light trap constantly emitted and re-captured the light.
“It’s clear that the light is trapped – there are photons circulating around the atoms,” Everett says. “The atoms absorbed some of the trapped light, but a substantial proportion of the photons were frozen inside the atomic cloud.”
Hmmm; like the graphic reminds of one of my posts.
In Brief.
- Quantum computers would run some 100 million times faster than your PC, but they have proven to be a monumental feat of engineering.
- In a new experiment, physicists managed to stop light, which helps us overcome challenges and brings us close to optical quantum computing.
A team of researchers at The Australian National University (ANU) may have found another work-around to bring us closer to quantum computing: The physicists have managed to find a new way to stop light.
Light was trapped by shining infrared lasers into ultra-cold atomic vapor. While the atoms absorbed some photons, a large amount were left in a frozen state in the atomic cloud — enhancing photon interaction with atoms or other photons.
Dramatic advances in laser technologies are enabling novel studies to explore laser-matter interactions at ultrahigh intensity. By focusing high-power laser pulses, electric fields (of orders of magnitude greater than found within atoms) are routinely produced and soon may be sufficiently intense to create matter from light.
Now, intriguing calculations from a research team at the Institute of Applied Physics of the Russian Academy of Sciences (IAP RAS), and reported this week in Physics of Plasmas, explain the production and dynamics of electrons and positrons from ultrahigh-intensity laser-matter interactions.
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