The following is a collection of links related to nonlinear conceptions of time—especially the concept of cyclical time, prominent in Eastern philosophical traditions—and philosophical contemplation on the nature of time in general.

Concentrichron: a clock and calendar made of concentric rings.

Chronodex: “Since the beginning of the diary making business, every single diary is made by representing time in fixed grids. To challenge this rigid representation, after exploring in deep thoughts the essence of my own perfect diary, I present to you my Chronodex idea.” See also: Facebook, Flickr, and Pinterest.

The Daily Rind: “… it’s a system that reminds me that days and years and life itself are inherently cyclical, as opposed to purely linear, and so challenges me by its very form to begin looking for patterns and recognizing habits — good or bad — where I might not have noticed them before.”

Mr. Reid on Time: “Decimalising time would also make calculations involving time a great deal simpler: no more need for modular arithmetic, just simple plus and minus. There would be no more worrying about AM and PM and no more need for the 24-hour clock.”

Arrows of Time: A project by Quanta Magazine. The human mind has long grappled with the elusive nature of time: what it is, how to record it, how it regulates life, and whether it exists as a fundamental building block of the universe. This timeline traces our evolving understanding of time through a history of observations in CULTURE, PHYSICS, TIMEKEEPING and BIOLOGY.

“In geometry, a cycloid is the curve traced by a point on a circle as it rolls along a straight line without slipping. A cycloid is a specific form of trochoid and is an example of a roulette, a curve generated by a curve rolling on another curve.”

The present is defined by the past, therefore, the future is defined in the present.