It’s that time of the week again when we take a look at the top news from the world of physics. As always, here are the top 3 news stories with the corresponding links. To receive these news to your email address, register for our email newsletter.
1. Acoustic Levitation Made Simple (Jan 5)
A team of researchers from the University of São Paulo, Brazil has developed a new levitation device that can hover a tiny object with more control than ever before. The device works by levitating polystyrene particles by reflecting sound waves from a source above off a concave reflector below, while changing the orientation of the reflector allows the hovering particle to be moved around.
This breakthrough may be an important step toward building larger devices that could be used to handle hazardous materials, chemically-sensitive materials like pharmaceuticals—or to provide technology for a new generation of high-tech, gee-whiz children’s toys. “Modern factories have hundreds of robots to move parts from one place to another,” said Marco Aurélio Brizzotti Andrade, who led the research. “Why not try to do the same without touching the parts to be transported?”
The map of mysterious interstellar molecules
2. An Uncertainty Relation Beyond Heisenberg (Jan 5)
The so called Heisenberg uncertainty principle, being one of the most important principles in quantum mechanics, guides the behaviour of quantum systems. In particular, the principle bounds the product of the variances of two incompatible observables such as the position and the momentum of a particle by the Planck constant.
However, the flaw of the Heisenberg relation lies in the fact that due to its product structure, it cannot fully capture the concept of incompatible observables. Now, a new paper by L. Maccone and A. K. Pati at the Physical Review Letters offers two new uncertainty relations that bound the sum of variances of two incompatible observables. In contrast to the well-known Heisenberg-Robertson relation, which bounds the product of variances, these new relations always give non-trivial bounds for all incompatible observables. e new relations derived in this paper can have fundamental implications, as they not only capture the incompatibility of observables; they also do it in terms of quantities that are physically measurable.
Recently Johns Hopkins astronomers have analysed the light of hundreds of thousands of celestial objects from the Sloan Digital Sky Survey. This resulted in a unique map of enigmatic molecules in our galaxy that are responsible for puzzling features in the light from stars. The so-called diffuse interstellar bands have been a mystery ever since they were discovered by astronomer Mary Lea Heger of Lick Observatory in 1922. While analyzing the light from stars, she found unexpected lines that were created by something existing in the interstellar space between the stars and the Earth. Further research showed that these mysterious lines were caused by a variety of molecules, however, it was not clear which of the many possible molecules were responsible for the phenomena.
“These results will guide researchers toward the best observations and laboratory experiments to pin down the properties and nature of these enigmatic molecules,” said Ting-Wen Lan, who led the study. Even though the scientists do not have the full map yet, statistical analysis offered some important insights into, which surroundings are more likely to host the elusive molecules.