¿Está vacío el vacío?

The video explores different perspectives on whether a glass is half full or empty, emphasizing that it is always full of air and gases. It discusses how temperature affects light emission, comparing it to heating metal. The concept of cooling to absolute zero is introduced, highlighting its theoretical impossibility. Finally, the nature of vacuum is examined, explaining that it is not truly empty but filled with low-energy states.

What is the lowest possible temperature, and why is it considered impossible to reach it in a finite number of steps?

Discuss the idea that the vacuum is not truly empty. What does this imply about the universe?