Something changed there.
Something changed here.
Between them was a signal.
What are you able to notice because something reached you?
Go notice a signal
- A clap in another room
- A smell from the kitchen
- Starlight through a window
- The phone in your hand. It is already an antenna
The screen is a door, not the destination.
What traveled
- ClapAir. Needs a medium. Slow next to light.
- Light, radio, hydrogenThe electromagnetic field. Vacuum is enough. Speed of light.
- A nerveVoltage, then chemistry. Fast for a body. Slow next to light.
- A smellMolecules on the air.
- The chirpSpacetime itself. Also the speed of light. Not sound.