Abstract: In underwater acoustic communication (UAC), channels are typically assumed to be stationary or slowly time-varying during short communication events, with a single statistical distribution ...

This puzzle is known as the problem of time, and it remains one of the most persistent obstacles to a unified theory of ...

Master the concepts of average velocity and position update in this physics tutorial. Learn step-by-step how to calculate motion, update positions over time, and solve related problems with clarity.

Time is almost up on the way we track each second of the day, with optical atomic clocks set to redefine the way the world ...

Many objects in space rotate. Earth completes a spin in roughly 24 hours, while Venus takes a whopping 243 Earth days. The ...

Time feels like the most basic feature of reality. Seconds tick, days pass and everything from planetary motion to human memory seems to unfold along a single, irreversible direction. We are born and ...