For the final sound-design project, Mateo promised to record one minute of perfect silence. His teacher raised an eyebrow but approved the plan. The city university had an anechoic chamber—a room built to swallow echoes—and Mateo's aunt arranged a supervised visit.

The chamber looked wrong before it sounded wrong. Foam wedges covered the walls, ceiling and floor, pointing inward like thousands of grey teeth. A suspended wire platform kept visitors above the wedges underfoot. When the technician sealed the heavy door, the ventilation stopped and the room seemed to expand.

Mateo pressed Record. At first he heard nothing. Then a soft thump arrived through the headphones. Another followed. He checked the microphone cable before realising the sound was his own heartbeat. A faint hiss rose and fell with his breathing. When he shifted his weight, a tiny creak came from inside his knee. The chamber had removed the room's sounds so completely that his body became the loudest thing in it.

He tried holding his breath, but the effort made his pulse faster. He set the recorder on the platform and stepped away; the microphone still captured the small electrical murmur of its own circuits. After eleven minutes, Mateo opened the door without obtaining a single second of what he had promised.

Back at school, he considered submitting nothing. Instead, he layered the heartbeat, breath, knee creak and circuit hum into a sixty-second piece. He titled it No Such Thing. The final sound was the chamber door opening, followed by the sudden flood of corridor noise.

His teacher listened twice. Mateo had failed to record silence, she said, but he had answered a better question: when the world becomes quiet, what remains?