Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: particle physics – Page 550

A team from Griffith’s Centre for Quantum Dynamics in Australia have demonstrated how to rigorously test if pairs of photons — particles of light — display Einstein’s “spooky action at a distance”, even under adverse conditions that mimic those outside the lab.

They demonstrated that the effect, also known as , can still be verified even when many of the photons are lost by absorption or scattering as they travel from source to destination through an optical fiber channel. The experimental study and techniques are published in the journal Science Advances.

Quantum nonlocality is important in the development of new global information networks, which will have transmission security guaranteed by the laws of physics. These are the networks where powerful quantum computers can be linked.

Read more

To the best of our knowledge, we humans can only experience this world in three spatial dimensions (plus one time dimension): up and down, left and right, and forward and backward. But in two physics labs, scientists have found a way to represent a fourth spatial dimension.

This isn’t a fourth dimension that you can disappear into or anything like that. Instead, two teams of physicists engineered special two-dimensional setups, one with ultra-cold atoms and another with light particles. Both cases demonstrated different but complementary outcomes that looked the same as something called the “quantum Hall effect” occurring in four dimensions. These experiments could have important implications to fundamental science, or even allow engineers to access higher-dimension physics in our lower-dimension world.

“Physically, we don’t have a 4D spatial system, but we can access 4D quantum Hall physics using this lower-dimensional system because the higher-dimensional system is coded in the complexity of the structure,” Mikael Rechtsman, professor at Penn State University behind one of the papers, told Gizmodo. “Maybe we can come up with new physics in the higher dimension and then design devices that take advantage the higher-dimensional physics in lower dimensions.”

Read more

For the first time, physicists have built a two-dimensional experimental system that allows them to study the physical properties of materials that were theorized to exist only in four-dimensional space. An international team of researchers from Penn State, ETH Zurich in Switzerland, the University of Pittsburgh, and the Holon Institute of Technology in Israel have demonstrated that the behavior of particles of light can be made to match predictions about the four-dimensional version of the “quantum Hall effect”—a phenomenon that has been at the root of three Nobel Prizes in physics—in a two-dimensional array of “waveguides.”

A paper describing the research appears January 4, 2018 in the journal Nature along with a paper from a separate group from Germany that shows that a similar mechanism can be used to make a gas of exhibit four-dimensional quantum Hall as well.

“When it was theorized that the quantum Hall effect could be observed in four-dimensional space,” said Mikael Rechtsman, assistant professor of physics and an author of the paper, “it was considered to be of purely theoretical interest because the real world consists of only three spatial dimensions; it was more or less a curiosity. But, we have now shown that four-dimensional quantum Hall physics can be emulated using photons—particles of light—flowing through an intricately structured piece of glass—a array.”

Read more

Climate Change Research: our team came up with this concept — https://www.behance.net/gallery/59176073/Climate-Change This team tested an instrument that gathers key data about aerosols—small, solid or liquid particles suspended in the Earth’s atmosphere—to better to assess their effects on weather, climate and air quality.

We recently put an instrument to the test that gathers key data about aerosols—small, solid or liquid particles suspended in the Earth’s atmosphere—to better to assess their effects on weather, climate and air quality. See what happened: http://go.nasa.gov/2BfdJdL

Read more

While bullet-proof body armor does tend to be thick and heavy, that may no longer be the case if research being conducted at The City University of New York bears fruit. Led by Prof. Elisa Riedo, scientists there have determined that two layers of stacked graphene can harden to a diamond-like consistency upon impact.

For those who don’t know, graphene is made up of carbon atoms linked together in a honeycomb pattern, and it takes the form of one-atom-thick sheets. Among various other claims to fame, it is the world’s strongest material.

Known as diamene, the new material is made up of just two sheets of graphene, upon a silicon carbide substrate. It is described as being as light and flexible as foil – in its regular state, that is. When sudden mechanical pressure is applied at room temperature, though, it temporarily becomes harder than bulk diamond.

Read more

Although solar panels might appear bright and shiny, in desert environments, where they are most frequently installed, layers of dust and other particles can quickly coat their surface. These coatings can affect the panels’ ability to absorb sunlight and drastically reduce the conversion of the sun’s rays into energy, making it necessary to periodically wash the panels with water. But often, in areas like Nevada, water resources are scarce.

Consequently, NEXUS scientists have turned their attention toward developing technologies for waterless cleaning. NASA has already been using such techniques to wash panels in the lunar and Mars missions, but their developed methodologies prove too expensive for widespread public application. NEXUS scientist Biswajit Das of UNLV and his team are aiming to develop a water-free cleaning technology that will be cost-effective for large-scale photovoltaic generation, whereby they look to nanotechnology, rather than water, to clean the panels. “Our mission is to develop a waterless, or at least a less-water cleaning technique to address the effect of dust on solar panels,” Das says. “Once developed, this method will significantly reduce water use for the future PV generation.”

Read more

A cylindrical rod is rotationally symmetric — after any arbitrary rotation around its axis it always looks the same. If an increasingly large force is applied to it in the longitudinal direction, however, it will eventually buckle and lose its rotational symmetry. Such processes, known as “spontaneous symmetry breaking”, also occur in subtle ways in the microscopic quantum world, where they are responsible for a number of fundamental phenomena such as magnetism and superconductivity. A team of researchers led by ETH professor Tilman Esslinger and Senior Scientist Tobias Donner at the Institute for Quantum Electronics has now studied the consequences of spontaneous symmetry breaking in detail using a quantum simulator. The results of their research have recently been published in the scientific journal Science.

Phase transitions caused by symmetry breaking

In their new work, Esslinger and his collaborators took a particular interest in — physical processes, that is, in which the properties of a material change drastically, such as the transition of a material from solid to liquid or the spontaneous magnetization of a solid. In a particular type of phase transition that is caused by , so-called Higgs and Goldstone modes appear. Those modes describe how the particles in a material react collectively to a perturbation from the outside. “Such collective excitations have only been detected indirectly so far,” explains Julian Léonard, who obtained his doctorate in Esslinger’s laboratory now works as a post-doc at Harvard University, “but now we have succeeded in directly observing the character of those modes, which is dictated by symmetry.”

Read more

Some of the earliest computers relied upon tape drives for storage, but we’ve since moved on to faster and more versatile storage technologies. Still, tape drives continue to exist in enterprise, and they’ve been advancing by leaps and bounds while you haven’t been paying attention. IBM just announced a new record in data storage density — 201 gigabits per square inch on a magnetic tape (that’s one square inch of it above). That works out to a whopping 330TB of uncompressed data on a single tape drive cartridge.

IBM reached this plateau in magnetic tape density by developing several new technologies. Older versions of IBM’s magnetic tape used a thin film of barium ferrite particles applied to the surface like paint. “Sputtered tape” uses several layers of thin metal film that are applied using a new vacuum technology. A layer of lubricant is also applied to the reading surface of the tape to keep the tape in good working order as it’s run through the drive. The higher density arrangement of magnetic nanoparticles will, of course, require new drive technology to read.

Read more