Physics Buzz

One night in late April, my husband happened to look out the window and noticed, passing over our valley in southwest Montana, a string of around 30 mysterious lights—too fast to be aircraft and apparently too numerous to be satellites. The next day, a string of emails lit up a local listserv. People who’d observed the lights were wondering what they’d seen, and readers who knew what they’d seen were quick to respond: This was Starlink , a network of satellites intended to deliver high-speed broadband Internet to areas of the globe where such connectivity is currently costly, unreliable, or inaccessible. Deployed by SpaceX, the aerospace company founded by busy tech entrepreneur and would-be Martian Elon Musk, the network will ultimately consist of thousands of satellites and, according to its website, is projected to provide worldwide coverage by 2021.    The night sky over Silverthorne, Colorado     Credit: Nathan Anderson on Unsplash The company got closer to that goal l

Imagine a world where everyone is right-handed. The world may not look different, but eventually, the question might arise: Why is no one left-handed? In the world of the molecules that make up the bodies of living things like DNA and RNA, this is a real question—and astrophysics researchers think they might have an answer. Molecules that have two different structures that are mirror images but can’t be superimposed possess chirality—or handedness. Our hands are good visual representations of chirality: When you stack your hands, back of hand to palm, it’s apparent that, while being mirror images, they can’t be superimposed as your thumbs jut out to the sides. While molecules have the option of being left- or right-handed, biomolecules such as amino acids, RNA, and DNA only occur in one form in nature. DNA, for example, is only ever a right-handed helix, sugar molecules are also right-handed, while amino acids are the lefties of the biomolecular world. These preferences each bi

The essence of the perfect slice of sourdough bread is in the air right now. It is even on your hands. The heart of the sourdough is the starter, a fermented culture of flour and water. The sour flavor of the dough comes from lactic acid bacteria (LAB) who live in relative harmony and competition with yeasts. The starter (also called “levain” or “mother”) is the source of all of the good qualities of sourdough bread: the tang, the spongy texture, and the nutritional properties. Although yeasts are commonly associated with baking and other fermentations, the forgotten heroes are the LAB who generally outnumber yeasts by 100:1 in the starter1. The initial mixture of flour and water makes an excellent home for LAB with an initial pH of 5.0-6.2 - which is more acidic than water - and rich in carbohydrates for the bacteria to consume. In these favorable conditions, lactobacillus species, such as L. sanfanciscensis, flourish and outcompete other types of bacterias. Lactobacillus are used i

Combatting the COVID-19 pandemic has become an international challenge and charge. It has highlighted the positive consequences of science operating on a global scale. It has shown how answers can be found quickly when scientists share results at unprecedented speed and research becomes increasingly open-access. It has shown that we must rely on scientists from a wide array of expertise to understand — and eventually control — this virus. We need epidemiologists, virologists, biologists, engineers, data scientists, and statisticians. We also need physicists in the mix. Here at Physics Buzz, we’ve previously explored how artificial intelligence has helped us fight pandemics. But I also wanted to know: how has physics research aided in the fight to combat this pandemic? How does physics research overlap with other sciences — including epidemiology, medicine, virology, among others — to uncover new knowledge about COVID-19? What is the role of physics in our pandemic response? A quic

What happens when you focus one of the world’s most powerful lasers on a spot so tiny it can be hidden by a human hair? Using the J-KAREN-P laser at the Kansai Photon Science Institute (KPSI) in Japan, a team led by researchers from the National Institutes for Quantum and Radiological Science and Technology (QST) in Japan investigated this extreme situation. As they report in the American Physical Society’s journal Physical Review Letters, the experimental results reveal a fundamental limit that’s key to optimizing the next generation of ultra-high-intensity lasers. The J-KAREN-P (Japan-Kansai Advanced Relativistic ENgineering Petawatt) laser at KPSI. Credit: QST. “[S]tate-of-the-art high-power laser facilities can produce extreme conditions like no other on earth,” explains Nicholas Dover, a postdoctoral researcher at QST and lead author of the new research paper. “To be precise, there is no other method we know of to concentrate as much energy into such a small spac

We’ve all wished for weightlessness at some point in our lives—that fantastical quality that powers the magic of flying broomsticks and fuels our fascination with space travel. Although we’re a long way from floating down the street, physicists have developed ways to mitigate the effect of gravity, from carefully aligning sound waves to mimicking free fall in reduced-gravity aircraft . But Kosuke Shibata and his colleagues at the Gakushuin University say they’ve developed a new tool for levitation: beams of light. Figure 1. Astronaut David Scott experiences weightlessness in a C-135 aircraft. Image credit: NASA It might sound rather Star Trek-esque, but the physics is real. Light can be described mathematically as a wave of electric and magnetic fields moving through space, and when a strong light source like a laser shines on an atom, the changing electric field interacts with the electric charges contained within the atom’s protons and neutrons. If done just right, the res

The electromagnetic spectrum, an assortment of energy wiggling throughout space and time, is overwhelmingly underappreciated in our lives. There is no combination of existence that could happen without it. To celebrate the role that light plays in our lives, our ecosystem, and the operation of the universe, UNESCO declared March 16th as the International Day of Light , a day to celebrate “ vital role of light and light-based technologies in science, culture and art, education and sustainable development”. Across the world, citizens are planning events to celebrate light in all of its forms. Everywhere around us are waves, whether we can see them or not. Out of all the waves traveling through space, we can only see a fraction. On earth, we’re only seeing ~44% of the radiation coming from the sun! Even so, scientists estimate that we can differentiate up to 10 million colors in the visible spectrum. Everything we can see in this universe is detected through waves, with wavelengths fa

UUltrasound is a powerful tool for looking inside the body. The scans see through layers of tissue to reveal pumping hearts, developing fetuses, troublesome blood clots, and injured muscles. They are relatively low-cost, portable, and have few side effects. Patients aren’t exposed to ionizing radiation or confined in a small space. They are, however, slathered in goo. Most of the time, having a body part temporarily coated in a cold, sticky substance and then pressed on by a technician is a small price to pay for an accurate diagnosis. But in some situations, like when it’s necessary to image a wound, this contact can be painful. That’s one of the downsides of ultrasound technology. Another is that some results can be influenced by the amount of pressure applied by the technician–it’s a very “hands-on” technique, especially compared to other types of medical imaging. In new research published in the journal Light: Science & Applications, a team of researchers from the Massachus

If you’re on the receiving end of a snapping shrimp’s attack, prepare to be stunned. Also known as pistol shrimp, these little crustaceans shoot lethal rounds at predators and prey at highway speeds—a direct hit can be outright fatal or shock the recipient into submission. It’s not just the force of the attack that’s stunning though, it’s the sound. Snapping shrimp are among the noisiest creatures in the ocean. Left: Researcher Ashlee Lillis holds a microphone to tank of snapping shrimp. Right: A snapping shrimp, note the large snapping claw. Credit: Woods Hole Oceanographic Institution. “They are hardly ever seen, and very cryptic in their habitat, but their sounds are ubiquitous,” says to Ashlee Lillis, a scientist leading the coral conservation activities in the US Virgin Islands for The Nature Conversancy. As a PhD student Lillis studied the soundtrack of the ocean and its impact on marine larvae. “I was fascinated by the most common biological sound in all of the recordings

One of the most captivating aspects of the summer Olympics is watching the world’s best athletes push their bodies to the edge of what is humanly possible. In 2016, the world watched in awe as Jamaican sprinter Usain Bolt won his third consecutive Olympic gold in each of three distances—the 100m, 200m, and 4x100m relay. Bolt is the fastest man in recorded history, reaching a top of speed of 12m/s, more than 27mph. Usain Bolt (Jamaica) in the lead during the 100 m heat of the 14th IAAF World Championships in Athletics in Moscow, Russia. Credit: Tobi 87 ( CC BY-3.0 ). His wins left me wondering about the science of it all. How fast is it humanly possible to run? Aside from willingness to get off the couch and train, what ultimately limits running performance? In new research published in the journal Science Advances , Vanderbilt University’s Amanda Sutrisno and David Braun explored these questions from a fascinating perspective. Braun leads the Advanced Robotics and Control Labo

The novel coronavirus outbreak has quickly become the largest pandemic in recent history, but it’s not unprecedented. The outbreak of the so-called “ Spanish Flu ”, an avian influenza virus, spread worldwide, infecting one-third of the population. While scientists are still learning how the coronavirus operates, we have lots of tools at our disposal to fight it. In the world of ever-growing datasets, artificial intelligence can make connections that even the most diligent of scientists miss. While they have a lot to learn before making insights, I believe AI can save the world. Visualization of the coronavirus (via Fusion ) Faster diagnoses Identifying positive coronavirus cases is critical for mitigating its spread, but that’s hard to do. In the US, a shortage of COVID-19 tests means that many more people have the virus than what we’re counting for. It also means that we’re likely underestimating the number of fatalities from the virus. We’re seeing shortages of the vital