Knots are everywhere — from tangled headphones to DNA strands packed inside viruses — but how an isolated filament can knot itself without collisions or external agitation has remained a longstanding puzzle in soft-matter physics.

Now, a team of researchers at Rice University, Georgetown University and the University of Trento in Italy has uncovered a surprising physical mechanism that explains how a single filament, even one too short or too stiff to easily wrap around itself, can form a knot while sinking through a fluid under strong gravitational forces. The discovery, published in Physical Review Letters, provides new insight into the physics of polymer dynamics, with implications ranging from understanding how DNA behaves under confinement to designing next-generation soft materials and nanostructures.

Soil is one of Earth’s largest carbon sinks, second to the ocean. New study discovers a key iron mineral in soil has a nanoscale mosaic of positive and negative charges. Varied charges, hydrogen bonding and strong chemical bonds enable mineral to trap carbon. Findings help explain why some carbon is locked in soils for centuries.

A University of Houston computational chemist has received a $1.96 million federal grant to study how light transforms small molecules, work that could open new avenues for storing and using chemical energy, and for designing materials that change when exposed to light.

Snow and ice can damage paved surfaces, leading to frost heaves and potholes. These become potential hazards for drivers and pedestrians and are expensive to fix. Now, researchers propose in ACS Sustainable Chemistry & Engineering a figurative and literal green solution to improve the durability of roads and sidewalks: an algae-derived asphalt binder. For temperatures below freezing, results indicated that the algae binder reduced asphalt cracks when compared to a conventional, petroleum-based binder.

SAN ANTONIO — December 15, 2025 — Southwest Research Institute (SwRI) has received $1.75 million in funding from the ENERGYWERX program to support a set of hydrogen-related projects. The eight projects focus on testing components for the hydrogen industry to improve energy infrastructure and support the use of this clean-burning fuel.

AIP’s 2026 Karl Taylor Compton Medal for leadership in physics is being awarded to Professor John Holdren of Harvard University and former Chief Science & Technology Advisor to President Obama. Named after prominent physicist Karl Taylor Compton, the medal is presented by AIP every two years to a highly a distinguished physicist who has made outstanding contributions to physics through exceptional statesmanship in science. Holdren was chosen by the selection committee “for his scientific leadership in engaging the public and promoting sound governmental policies and key international agreements.”