Mechanical clock and atomic clock

From general relativity, gravity slows down time. Time would run faster further up, where gravity is weak. With atomic clock, time speeds up further up. This seems to confirm general relativity. But with mechanical clock, time slows down further up. Isn’t more natural to regard clocks as time keeping instruments with different mechanisms? Isn’t more natural to leave time itself alone?

But authorities in physics insist time dilation is a fundamental concept. The following is an answer from copilot.

That’s an interesting perspective! The way we describe the effects of gravity on time and clocks can indeed be nuanced. Here’s a breakdown of why we often say “time speeds up” or “slows down” in the context of relativity:

Time Dilation and Relativity

In the framework of general relativity, time dilation is a fundamental concept. It describes how time itself is affected by gravity and relative motion. According to Einstein’s theory, time is not an absolute constant but can vary depending on the strength of the gravitational field and the relative velocity of observers.

Mechanical vs. Atomic Clocks

• Mechanical Clocks: These clocks are influenced by gravity in a more mechanical sense. For example, a pendulum clock might run slower at higher altitudes due to changes in gravitational force affecting the pendulum’s swing. This is more about the physical mechanics of the clock rather than a fundamental change in the flow of time.

• Atomic Clocks: These clocks measure time based on the vibrations of atoms, which are influenced by the gravitational field. When we say an atomic clock runs faster at higher altitudes, we are observing a fundamental effect predicted by general relativity: time itself is passing more quickly in a weaker gravitational field.

Why We Say “Time Speeds Up”

The reason we say “time speeds up” or “slows down” is because, according to general relativity, the passage of time is relative and can be affected by gravity. This isn’t just about the clocks themselves but about how time is experienced differently in varying gravitational fields. When an atomic clock runs faster at higher altitudes, it reflects that time is indeed passing more quickly there compared to a stronger gravitational field.

Conceptual Understanding

Your suggestion that “time flow is constant while the pace of measuring devices may change with gravity” is a valid way to think about it from a practical standpoint. However, in the context of relativity, the changes in the pace of atomic clocks are used to illustrate that time itself is not constant and can be warped by gravity.

Conclusion

Both perspectives are valuable. The relativistic view helps us understand the fundamental nature of time and space, while your practical view emphasizes the behavior of measuring devices. This dual understanding enriches our grasp of how the universe operates.

Would you like to explore more about the implications of time dilation or other aspects of relativity?

: NASA - Einstein’s Theory of Relativity, Critical For GPS : Ohio State University - GPS and Relativity