First Measurement of Pressure from Individual Particles Achieved

Researchers at Yale University have successfully measured the pressure exerted by individual particles for the first time, marking a significant breakthrough in precision physics. The team, led by Yu-Han Tseng, developed an ultra-sensitive sensor featuring a 100-nanometer silica sphere suspended by a laser beam. When particles collide with the sphere, the resulting motion alters reflected light, allowing for real-time detection of single impacts. Tested in an ultra-high vacuum with various gases, the device's measurements aligned perfectly with mathematical predictions. This technology enables the definition of extreme high-vacuum regimes where traditional sensors fail, as it counts individual molecular collisions rather than relying on average effects. Beyond redefining vacuum standards, the device holds promise for astronomical applications, such as analyzing low-pressure interstellar spaces. Most notably, researchers aim to use this sensitivity to detect hypothetical sterile neutrinos. These elusive particles could resolve long-standing anomalies in particle physics and potentially constitute dark matter. The study demonstrates how tracking individual particle interactions, previously observable only as averaged blurs, can open new avenues for understanding fundamental forces and mysterious components of the universe.