WikiMechanics

Asterias, Jean Baptiste Lamarck. Tableau Encyclopédique et Méthodique des Trois Regnes de la Nature, Paris 1791-1798. Photograph by D Dunlop.

WikiMechanics begins with the premise that we can understand time by what we see, hear and feel. And according to Albert Einstein time is what a clock tells.¹ So to make sense of time we are going to give some consideration to how a clock can be understood as a collection of sensations. Over the next few pages three preliminary ideas are discussed.

• Temporal orientation: is a binary description of how thermal feelings change. For example, a chain of events might be described as warming or cooling.

• Historical order: we say that a chain of events is historically ordered if it has the same temporal orientation as the Earth.

• Chronological order: a chronologically ordered chain parses sensation into events that are related to terrestrial days.

Einstein also taught us that time depends on some frame of reference. So first we say a few words about reference frames.