The particles that make up light, photons, may live for at least 1 quintillion (1 billion multiplied by 1 billion) years, new research suggests.
If photons can die, they could give off particles that travel faster than light.
Many particles in nature decay over time. For instance, radioactive atoms are unstable, eventually breaking down into smaller particles and giving off energy as they do so.
Scientists generally assume photons do not break down, since they are thought to lack any mass with which to decay. However, while all measurements of photons currently suggest they have no mass, they might instead potentially have masses too small for current instruments to measure. [10 Implications of Faster-Than-Light Travel]
"How much do we actually know about photons?" asked particle physicist Julian Heeck at the Max Planck Institute for Nuclear Physics at Heidelberg, Germany. "They led to several revolutions in science, but their properties are still a puzzle."
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