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Business PHYS TECH_Technology

Laser technology allows self-driving cars to see around corners

Researchers working at Stanford University have developed a new laser imaging technique that could one day allow self-driving cars to see around corners, a new study published in the journal Nature reports.

The process works exactly as imagined, which means it can help autonomous cars stop at blind turns or navigate through tricky roads to avoid potential danger. In testing, the team found it helped stop cars that would normally hit a child coming around a turn.

This technology is important because traffic accidents — which claim more than 1.2 million lives a year — are the second leading cause of death for children ages 5 to 14. As a result, implementation of the system could significantly cut down on those numbers.

“This is a big step forward for our field that will hopefully benefit all of us,” said study co-author Gordon Wetzstein, assistant professor of electrical engineering at Stanford University, in a statement.

To build the new system, researchers installed a laser device next to an incredibly sensitive photon director. That then allowed them to shoot laser beams at a wall and reflect them onto a hidden object. From there, those beams then traveled off the detector and back to the car.

That process — known as a scan — takes between roughly a couple of minutes to an hour to complete. Then, an algorithm takes in the protons as blob-like shapes and transforms them into crisp images in less than a second.

The team calls the technology “confocal non-line-of-sight imaging” or C-LOS imaging. While this is not the first time such a process has been used to find hidden objects, it is one of the furthest along. The team hopes they can further expand on the system to make it quicker and more efficient.

“If the other vehicle or person is arriving too fast, implying that there could be a collision, then the system could feed this information to the car, which could then autonomously decide to slow down,” said Daniele Faccio, a physicist at Heriot Watt University who was not involved in the research, according to Tech Times.

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PHYS

DNA robot could one day move molecules around inside the body

A team of scientists working at the California Institute of Technology have developed a robot made entirely out of DNA, according to recent research in the journal Science.

This new “autonomous molecular machine” is constructed out of a single strand of DNA, and is able to perform tasks at the nanoscale level. It can “walk” around a surface, pick up molecules, and then drop them off in specific locations. While the device is too small for human applications, such a tiny helper could lead to new molecular research.

The team built the new bot by constructing three basic building blocks: a “leg” with two “feet” for walking, an “arm” and “hand” for picking up cargo, and a segment that can recognize a specific drop-off point. Each of these components is comprised of a few nucleotides that are contained within a single strand of DNA.

Though the bot in the study operates in one set way, the building blocks could in theory be rearranged for many different tasks.

In the study, the team used fluorescent molecules to document how well the robot moved certain objects to different locations. It successfully sorted six scattered molecules into their correct places within 24 hours. Then, when more robots were added to the surface, the same task took even less time.

That test is important because it shows that multiple robots can work together to make one task more efficient.

“I thought it was a fairly major step forward in molecular robotics,” said John Reif, a DNA nanoscientist at Duke University who was not involved in the research, according to The Los Angeles Times. “[The experiment] demonstrated that a little army of DNA robots can operate in parallel independently to work together to solve a problem.”

The team managed to create the unique machine because DNA has programmable chemical and physical properties. Each strand is made up of four different molecules — known as nucleotides — that are arranged in a string called a sequence. By rearranging such nucleotides the team can get the molecules to act in the way they want.

Though the process is still in the works, it holds a lot of promise for future research. The team hopes to expand on the new technology in order to see what other applications it might have.

“We don’t develop DNA robots for any specific applications,’ said study co-author Lulu Qian, a researcher at the California Institute of Technology, according to Phys.org. “Our lab focuses on discovering the engineering principles that enable the development of general-purpose DNA robots. However, it is my hope that other researchers could use these principles for exciting applications, such as using a DNA robot for synthesizing a therapeutic chemical from its constituent parts in an artificial molecular factory, delivering a drug only when a specific signal is given in bloodstreams or cells, or sorting molecular components in trash for recycling.”

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PHYS TECH_Technology

New light form could lead to better quantum computing

A group of researchers from the Massachusetts Institute of Technology and Harvard University have created a new form of light that shows photons are able to bind together, according to a study in the journal Science.

Typically, photons — the particles that make up light — do not interact with each other. In fact, if scientists put two into each other’s paths they will still find a way to pass by without touching. This new study changes that notion by revealing that photons can interact and bind together in groups of two or three.

To make this discovery, the team shone a weak laser beam through a dense cloud of the ultracold atoms, which then caused the photons to bind into either pairs or triplets. The photons attracted to each other, and the bound ones also appeared to acquire some mass during the process. That additional weight slowed down their speed by about 100,000 times.

Such interactions are completely new, and created a type of photonic matter previously unknown to science.

“The interaction of individual photons has been a very long dream for decades,” said study co-author Vladan Vuletic, a researcher at the Massachusetts Institute of Technology, according to International Business Times. “Photons can travel very fast over long distances, and people have been using light to transmit information, such as in optical fibers. If photons can influence one another, then if you can entangle these photons, and we’ve done that, you can use them to distribute quantum information in an interesting and useful way.”

While the team is not exactly sure why the interaction occurred in the way that it did, they believe it might be because as a single photon moves through the cloud of rubidium atoms, it briefly lands on a nearby atom before skipping to another. However, if another photon is also moving through the cloud, it can sit on a rubidium atom as well.

That then forms a polariton, which is part photon and part atom. From there, two polaritons can interact through their atomic component. Not only does that work with two protons, it can also work with three to create an even stronger bond.

This new type of light has a lot of potential, especially in the world of quantum computing. The team hopes to expand on their research and see what other interactions they can find moving forward. 

“It’s completely novel in the sense that we don’t even know sometimes qualitatively what to expect,” added Vuletic, in a statement. “With repulsion of photons, can they be such that they form a regular pattern, like a crystal of light? Or will something else happen? It’s very uncharted territory.”

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PHYS Physics Science

Large Hadron Collider detects rare particle decays

CERN’s Large Hadron Collider (LHC) near Geneva has been back to smashing protons at high speeds since the completion of its two-year refit for greater power potential. CERN scientists recently reported evidence of particle decays that had been predicted but had never been detected.

According to the Los Angeles Times, the decay pattern observed “could help researchers test the limits of the standard model of particle physics and probe unexplained cosmic phenomena, including the existence of dark matter and the dearth of antimatter in the universe.”

“From the scientific standpoint, this is big, heady stuff. All the puzzles of physics could fall into place or they could just remain mysteries based on what we learn from these decays,” LHC researcher Joel Butler of Fermilab said. “This is kind of a fantastic time in physics, where many mysteries might get resolved.”

While the standard model of particle physics aligns well with previously detected particles like the Higgs boson, it does not adequately explain the nature and behavior of dark matter, dark energy or antimatter. Dark matter is not directly detectable and is thought to account for much of the mass and therefore gravitational influence in the universe. Dark energy is believed to be the force behind the universe’s increasing rate of expansion. Antimatter is thought to have been created alongside matter, but according to traditional models, matter and antimatter should have destroyed one another by now.

The type of particles involved in the groundbreaking decay observations are known as neutral B mesons, which decay quickly into other particles. Mesons are made up of quarks, of which there are six known types. The research team looked at data collected by the LHC concerning the decay rates of two types of B meson, one of which performed at a rate similar to what the standard model predicts, and one of which decayed at a rate almost four times higher than predicted.

Butler noted that the discrepancy could possibly be attributed to the small sample size of data regarding the oddly performing B meson. “If that holds up, it will be very interesting, but for right now, it’s best explained as a statistical fluke. It’s got our attention, let’s put it that way,” Butler said.

The team will be collecting more data to explore which particle behaviors remain in keeping with the standard model and which particle decays either support or rule out theories within supersymmetry. Supersymmetry is a model of particle physics which assumes that each particle has a more massive “superparticle” twin, which would decay quickly into more stable and less massive particles. Under the auspices of supersymmetry, the lightest and most stable of these particles could be the elusive form of dark matter.

The results were published in the journal Nature.

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NWT_Energy PHYS Physics Science

Hydrogen may turn metal within planet interiors, study reports

A team of international physicists have used lab-based mimicry to prove hydrogen can turn into liquid metal when put into conditions commonly found inside the interiors of giant planets, a new study published in the journal Science reports.

Hydrogen is the simplest and most abundant element in the universe. However, despite that, scientists know relatively little about it. There are many mysteries surrounding the substance, and one of the biggest is how it behaves on other worlds.

For instance, while the element is a gas on the surface of large planets like Jupiter and Saturn, research suggests it becomes a metal when inside those world’s interiors.

“This transformation has been a longstanding focus of attention in physics and planetary science,” said lead author Peter Celliers, a researcher at the Lawrence Livermore National Laboratory, according to Phys.org.

In the study, the team focused on the gas-to-metallic-liquid transition in the molecular hydrogen isotope deuterium. They looked at how deuterium reflects light and then analyzed the way those properties changed at both six million times normal atmospheric pressure and at temperatures lower than 3,140 degrees Fahrenheit.

The reason the team focused specifically on reflectivity is because it can often show if something is metal.

Analysis revealed that under roughly 1.5 times normal atmospheric pressure (150 gigapascals) the deuterium switched from transparent to opaque, which means it absorbed light instead of allowing it to pass through. It then moved to a metal-like reflectivity started at nearly 2 million times normal atmospheric pressure (200 gigapascals).

That transition is important because it could help scientists get a much better picture of, not just other planets, but the physical properties of the universe as a whole.

“To build better models of potential exoplanetary architecture, this transition between gas and metallic liquid hydrogen must be demonstrated and understood,” explained study co-author Alexander Goncharov, a researcher at the Carnegie Institution of Washington. “Which is why we focused on pinpointing the onset of reflectivity in compressed deuterium, moving us closer to a complete vision of this important process.”

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NWT_Energy PHYS Physics Science

Researchers at CERN are on a subatomic hunt to detect rare particle decay

An experiment at CERN in Geneva, called NA62, is designed to let scientists watch a rare kind of particle decay, writes Ryan F. Mandelbaum for Gizmodo. Most particles, with the exception of the ones out of which we ourselves are made, and a couple of others—fall apart (decay) into other particles in a tiny fraction of a second. (Some of these particles survive only a trillionth of a trillionth of a second, or even less!)

The physicists working on the NA62 experiment are searching for subatomic particles that may reveal new laws of physics. Using a new detection method, the team may have finally spotted what they’re looking for. They are hunting for quarks, the building blocks of other subatomic particles. There are six kinds: the common up and down quark, the strange and charm quarks, and the rarest top and bottom quarks.

Protons and neutrons contain only up and down quarks. The experiment’s goal is to manufacture as many kaon particles, as possible. Kaons contain an up quark, along with the antiparticle of the strange quark. NA62 produces kaons by hitting a target with a beam of high-energy protons from an adjacent particle accelerator. The team passes the beam through a detector and makes measurements while the particles are traveling.

An incredibly rare, on-in-10 billion result, is that it splits into a neutrino, an antineutrino, and a “pi-on.” The team presented their first candidate at a seminar held by CERN. They spotted a potential instance of this particular kaon decay.

“They’re not at a point of scientific significance yet, but they’ve demonstrated that their technique works,” Bob Tschirart, chief project officer of the Fermi National Lab, said. He pointed out that NA62 has the potential to observe as many as 100 events. Given the one-in-ten billion odds, that could bring the uncertainty in the measurement down by a lot.

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PHYS Physics Science

Higgs boson decay process observed for first time

Nearly six years after first discovering the elusive Higgs boson particle, scientists at the Large Hadron Collider have managed to finally observe its most common decaying process, two new studies (1, 2) report.

In the research, a team of physicists noted the boson decaying into two smaller particles — a bottom quark and an antibottom quark. That falls right in line with the the Standard Model of particle physics, which predicts a Higgs boson will decay into bottom quarks roughly 60 percent of the time.

However, as common as that is for the particle, the process has proved difficult to track. That is because the Higgs boson only comes about through the collision between two protons. In addition, even if that process does occur and the boson comes about, the particle only exists for one-septillionth of a second before it decays into less massive particles.

It is those particles that scientists used to infer the Higgs boson’s existence.

Typically, the particles decay into either a fermion-antifermion pair, a pair of photons, or a pair of gauge bosons. However, bottom quarks are more complicated because every proton-proton collision creates subatomic particles, including bottom quarks.

As Higgs boson only exist for a fraction of a second, researchers have not been able to tell if bottom quarks come from a decaying Higgs boson or the result of a proton collision background processes.

To shed light on that, researchers combined data from the first and second runs of the Large Hadron Collider and then analyzed that data to try and find bottom quarks from the particle showers they produced. Once there, they traced the bottom quarks back to a Higgs boson.

“Finding just one event that looks like two bottom quarks originating from a Higgs boson is not enough,” said co-author of one of the studies Chris Palmer, a physicist at Princeton University, according to Science Alert. “We needed to analyse hundred of thousands of events before we could illuminate this process, which is happening on top of a mountain of similar-looking background events.”

That study enabled the team to specifically illuminate Higgs events, which then shed light on how the particle comes about.

This finding is important because it once again confirms the Standard Model of particle physics, opening up new possibilities for scientists to better study the Higgs boson in greater detail. It could also give them a chance to see if it interacts with mysterious particles like dark matter.

“The experiments continue to home in on the Higgs particle, which is often considered a portal to new physics,” said Eckhard Elsen, CERN Director for Research and Computing, according to Phys.org“These beautiful and early achievements also underscore our plans for upgrading the LHC to substantially increase the statistics. The analysis methods have now been shown to reach the precision required for exploration of the full physics landscape, including hopefully new physics that so far hides so subtly.”

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Business PHYS TECH_Technology

Metalens technology could revolutionize future devices

Researchers from Harvard University have developed a type of metalens that can focus the entire spectrum of light on a single point. 

Typically, technology gets smaller and more efficient over time. However, optical lenses — which are in everything from cameras to microscopes — do not follow this rule. That is because researchers have not yet been able to make them more efficient and more compact at the same time.

However, the team in the new study may have gotten around that obstacle with metalenses — tiny, flat devices that use specially engineered nanostructures to focus light. Such lenses mimic the way traditional curved lenses work, but only take up a fraction of the space.

In the research, scientists created a type of metalens that is able to focus the entire visible spectrum of light on single point in high resolution. Before the study, such a feat only occurred when multiple traditional lenses were stacked on top of each other.

It is not easy to focus the entire visible spectrum because each wavelength moves through materials at different speeds. That then causes distortions known as chromatic aberrations. Many optical instruments, such as cameras, get around those issues by using curved lenses with different thicknesses and materials, but that then lowers efficiency.

“Metalenses have advantages over traditional lenses,” said study co-author Federico Capasso, a researcher from the Harvard John A. Paulson School of Engineering and Applied Sciences, according to International Business Times. “Metalenses are thin, easy to fabricate and cost effective. This breakthrough extends those advantages across the whole visible range of light. This is the next big step.”

The new metalenses are paper-thin and have an array of tiny nanostructures made from titanium dioxide. Those structures focus light equally so that all wavelengths arrive at the focal point at the same time and eliminate chromatic aberrations. The design also dramatically reduces thickness and design complexity compared to composite standard lenses.

While the technology is still in the early stages, the quality of images produced with metalenses exceeds those created with traditional lenses. In addition, as they are so small, metalenses are much easier to mass produce than curved ones.

The team next plans to expand on the study by incorporating their new lens into common optical devices, such as cameras, and to scale up the design to about 1 cm in diameter. That could then increase their applications.

“Using our achromatic lens, we are able to perform high quality, white light imaging. This brings us one step closer to the goal of incorporating them into common optical devices such as cameras,” said study co-author Alexander Zhu, a researcher at Harvard University, according to International Business Times.

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PHYS Physics Science

World’s fastest rotor spins 60 billion times a minute

Researchers from Purdue University have created a tiny rotor that makes 60 billion revolutions a minute, marking it as the fastest-spinning human made device in history.

The new technology is important because, not only does it push the boundaries of physics, but it may also help researchers better understand the mechanisms of quantum physics.

The rotor may even give a glimpse into the fundamentals of the universe, including the way gravity and friction operate in a vacuum.

“This study has many applications, including material science,” said study co-author Tongcang Li, a researcher at Purdue University, in a statement. “We can study the extreme conditions different materials can survive in.”

The nano-rotor may lead to various investigations within the world of physics. It is made up of a silica nanoparticle and shaped like a dumbbell. To develop it, researchers suspended it in a vacuum with a laser than can be polarized in a straight line or circle.

When the laser is in a circle the device spins. However, when the laser is straight the device vibrates in a way that allows scientists to study weak forces.

Both of those modes are significant and will likely be utilized in future research.

In addition, suspending a nanoparticle in a vacuum allows for extremely precise measurements that are not affected by natural forces like temperature or air flow. In that way, such information cannot be gathered anywhere else.

Though the rotor is tiny there is a lot that it can tell researchers about the forces that drive the universe.

“People say that there is nothing in vacuum, but in physics, we know it’s not really empty,” added Li, according to Science Alert“There are a lot of virtual particles which may stay for a short time and then disappear. We want to figure out what’s really going on there, and that’s why we want to make the most sensitive torsion balance.”

The research is published in Physical Review Letters.

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PHYS

Scientists discover more evidence of water on Jupiter’s moon Europa in old images

Scientists discover images of what seems to be the Galileo orbiter flying through a plume of water shooting out from Jupiter’s moon Europa twenty years ago. On December 16, 1997, Galileo flew 400 kilometers above Europa’s surface and recorded an isolated spike in the magnetic field along with a spike in the energy of the particles it detected, writes Ryan F. Mandelbaum for Gizmodo.

Looking at the twenty-year evidence with fresh eyes, a team of researchers believe the spike was Galileo flying through a plume of water. “This wasn’t planned out,” says study author Xianzhe Jia from the University of Michigan. “It just so happened that the spacecraft passed through a region where we saw plumes.” When NASA announced in 2013 that Hubble spotted what appeared to be water vapor above the moon’s south pole, Jia and his team decided to look for more evidence of the plumes using images taken by Galileo. They found what they were looking for–the evidence seemed clear.

Jesse Christiansen, staff scientist at the NASA Exoplanet Archive, is excited by the results. “It’s incredible that these authors were able to go back to 20-year-old observations from the Galileo spacecraft with new information and fresh eyes and find this smoking-gun evidence that Galileo encountered one of Europa’s plumes,” he told Gizmodo. Scientists are preparing for the “Europa Clipper” mission that would potentially sample the plumes for biological material, writes Mandelbaum. Grant Tremblay, astrophysicist at Harvard-Smithsonian Center for Astrophysics, believes the images offer more evidence of water on Jupiter’s moon. “Europa’s possible subsurface ocean remains among the best candidate harbors of extraterrestrial life in our Solar System.”