Distance, duration and dimension

There are many kinds of space. The most common space is that of positions, that is, distances and directions. There is also velocity-space. There is force-space. There is duration-space, too.

Particles travel on trajectories, points move on curves, vehicles travel on streets or routes, etc. Trajectories have distances traveled, travel times (durations), velocities, accelerations, etc. These are one-dimensional curves in three-dimensional space.

Trajectories also go in various directions. Travel distances, durations, velocities, forces, etc. have directions, that is, they are vectors.

Thus distances and durations are both properties of trajectories with magnitudes and directions. They are both vectors with dimensions. Travel distance is a measure of space so distance-spaces are a form of space. Duration or travel time is a measure of time so duration-spaces are a form of time.

There is a symmetry between travel distance and travel time. A trajectory or trip can be measured either or both ways. An odometer measures travel distance for example. A clock on a vehicle can measure travel time. Together they measure speed. Or if the speed is known, then the travel distance can be converted into travel time and vice versa.

If distance is 3-dimensional, then so is duration. Since duration is a form of time, the duration-space of 3-dimensions is 3-dimensional time. That is, time has 3-dimensions.