Xiangxiang Ren

Inside the receiver of a telescope aimed at the oldest glow in the universe sits a tiny thermometer chip. It's so sensitive that the heat from a single photon can warm it noticeably. But to hear that whisper of heat, you need a middleman — an amplifier that doesn't add its own noise.

Picture a room where hundreds of people are talking at once while you strain to hear a pin drop. That is essentially how physicists with the PandaX-4T collaboration listened for silence inside 3.7 tonnes of liquid xenon.