# Time and motion

In relativity, two clocks need not agree. A clock on a fast journey runs slow, and a clock higher in a gravitational field runs a little faster than one lower down. Satellite navigation has to correct for both effects to stay accurate.

Connects to:
- [Geometry](https://mapideas.org/i/mat_geometry)
- [Clocks](https://mapideas.org/i/ti_clocks)
- [The arrow of time](https://mapideas.org/i/ti_arrow)
- [Gödel’s rotating universe](https://mapideas.org/i/ti_godelmetric)
- [Light takes time](https://mapideas.org/i/as_light)
- [Is there a shared now?](https://mapideas.org/i/q_time_now)
- [Does time flow?](https://mapideas.org/i/q_time_flow)
- [How accurate can a clock be?](https://mapideas.org/i/q_time_clock)
- [What is the far sky like now?](https://mapideas.org/i/q_astro_now)

Sources:
- [Wikipedia: Time dilation](https://en.wikipedia.org/wiki/Time_dilation)
- [Wikipedia: Global Positioning System: Relativity](https://en.wikipedia.org/wiki/Global_Positioning_System#Relativity)

Source: https://mapideas.org/i/ti_relativity · open on the map: https://mapideas.org/#ti_relativity