|Time: A. Time is a dimension in which events are arranged. At first, no direction (before / after) is defined with this. A time direction can be obtained in the context of the Second Principle of Thermodynamics. However, a global framework must be assumed, within which there is an increase of entropy. The assumption of increasing entropy does not apply to the comparison of local events. B. In the case of the subjective time, the question of direction is less problematic. The perceived time direction is expressed by the learned use of the terms "before" and "after". See also time arrow, time travel, time reversal, symmetry, duration, space time, relativity theory, four-dimensionalism, world lines._____________Annotation: The above characterizations of concepts are neither definitions nor exhausting presentations of problems related to them. Instead, they are intended to give a short introduction to the contributions below. – Lexicon of Arguments. |
Def Time/Feynman: it's how long we wait. It can probably not be defined any further. It is important how we measure it.
Time Measurement/Measurement: one possibility: use something that changes periodically.
History: to be able to use the day as a measure, they had to make understand that days are not always of the same length; a different instrument was needed for that, e.g. an hour glass.
But with that they had not yet proven that they are periodic! >Covariance.
We can simply say that our definition of time is based on the repetition of an obviously periodic event._____________Explanation of symbols: Roman numerals indicate the source, arabic numerals indicate the page number. The corresponding books are indicated on the right hand side. ((s)…): Comment by the sender of the contribution.
Vom Wesen physikalischer Gesetze München 1993
Vorlesungen über Physik I München 2001