Since the 1960s, scientists who study X-rays, lightning and similar phenomena have observed something curious: In lab experiments replicating these occurrences, electrons accelerated between two electrodes can be of a higher energy than the voltage applied. According to Penn State researchers, this defies an assumption in physics that the energy of the electrons should correspond with the voltage applied. Despite the decades-long awareness of this apparent contradiction, researchers couldn’t figure out why this was happening.  

Recently, a team of Penn State researchers used mathematical modeling to explain the underlying mechanism at play. They published their results in Physical Review Letters. 

The first-known direct observations of the movement of microfiber plastics through a thin layer of soil-like particles show that they tend to tumble, roll and sometimes get stuck in spaces. The findings, reported in the journal, Water Resources Research, mean that the fibers could get easily trapped in sediment. The work helps to improve understanding of the exposure risks and possible health impacts of the pervasive pieces of plastic, which are the largest pollutant in the world by mass.

The Intergovernmental Panel on Climate Change (IPCC), a body of the United Nations, has long been at the forefront of climate science, regularly producing state-of-the-science assessments and possible solution pathways for policymakers.  In a first-of-its-kind ethnographic study, researchers from Indiana University Bloomington and Princeton University provide insights into the human and scientific dynamics that shape global climate assessments and sea level rise projections in the IPCC’s Sixth Assessment Report (AR6).  

Researchers developed a fully integrated photonic processor that can perform all the key computations of a deep neural network on a photonic chip, using light. This advance could improve the speed and energy-efficiency of running intensive deep learning models for demanding applications like lidar, astronomical research, and navigation.