I have been annoyed by official definitions of time from many Google searches and decided after listening to Sean Carroll's podcast to write my own. Here is what I did so far:

What is time? A state that changes.

What does time look like? It is perceived as a non-spatial continuum of changing states where each state has the most infinitely small differences compared to any other state in the continuum.

The arrow of time? A state in high entropy is not changing, and so only a state that has low entropy can be a state that can change. Any changing state therefore is perceived as a state changing with linear direction governed by the entropy of the continuum.

Please let me know if I used any time-like words, or you have some better definitions.

  • $\begingroup$ Defining time as change is sensible to me as well. But that doesn't conflict with any official definition of time, as far as I know. $\endgroup$
    – Steeven
    Sep 17 at 9:49
  • $\begingroup$ Why are you annoyed by 'official' definitions of time? Note that the concept of time can be notoriously difficult, and even more so if you're not a student of physics (which I'm presuming you are, correct me if I'm wrong). $\endgroup$ Sep 17 at 11:22
  • $\begingroup$ Time is a lot different than everyday intuition would lead you do expect - What is time, does it flow, and if so what defines its direction?. Also, could you add a link to the podcast? $\endgroup$
    – mmesser314
    Sep 17 at 11:27

What is time? A state that changes.

There are a couple of problems here. You have to define what you allow to be a "state" and what you allow to vary when the state "changes" i.e. what is it changing with respect to.

To illustrate these problems, suppose we define a state as "the average temperature at a given location on the surface of the Earth averaged over the year 2020". The average temperature is not the same at all locations, so this state "changes", but it changes with respect to space rather than time.

The difficulty is that if you qualify "state" to mean "state at a given instant in time" and you qualify "changes" to mean "changes with respect to time" then you have introduced time into your definition of time, which is circular. I don't see how you can appropriately qualify "state" and "changes" without using time within your definition.

  • $\begingroup$ i never qualify 'state to mean state at a given instant of time'. state is anything as defined different from anything else given that a change exists, irrispective of time. all of time could happen instantaneously and it wouldnt matter to the definition. changes are what quantify time, not the other way around. $\endgroup$
    – Jase
    Sep 17 at 11:10

You would be better to conflate your first two questions and define time as a continuum of non-spatial change, as the question 'what does time look like?' is literally meaningless-we cannot see time.

Your statement about the arrow of time is false. High entropy does not rule out change over time.

The idea of time having a direction is unnecessary- one can consider time to be a cumulative measure of change, which by definition is always positive.


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