Also, if time does exist, doesn’t there have to be a definable beginning or end? Otherwise it’s just infinity which to me suggests the absense of time.
I partially read “The Discoverers” by Daniel Boorstin several years ago and he discussed how different societies conceptualized of time and how they kept time. And it has had me wondering ever since. Then I started exploring Zen Buddhism which emphasizes the present moment as the only tangible reality, along with the illusion of the ego, which only furthered my questioning.
EDIT – I am aware that the concept of time is based on the revolution of the Earth and it’s moon. However, that is just how humans conceive of time. That’s not proof of time itself.
EDIT 2 – The explanation of timespace and relativity is the best from an objective point of view. No matter how much I read or watch, it was always a bit hard to grasp but it makes sense in terms of change or entropy. The reality of time being flexible vs the human perception of time being linear and unchangeable gets closer to what I am asking.
EDIT 3 – “Exist” is a tricky word.
In: 7871
We can observe that things change and that things happen; for example the arms on a clock always seem to be in a different position than our memory tells us they were. In fact, it seems like nothing in our universe is ever constant or ever stands still. “Time” is just the human awareness that everything seems to be in flux, and that it seems to be “one directional” (things don’t change to be like they used to be; everything is always slightly different), and “time” is also how humans place order on this flux (e.g. X happened before Y, but after Z) and also how we measure how much flux has happened.
“Time” as some sort of power or energy like in science fiction probably doesn’t exist. “Time” is just the observation that things change.
So you’re sort of halfway to understanding time as a concept, because you’ve started to question the idea that the things that we usually use to mark the passage of time — seconds and minutes and hours, and even things like ‘planetary rotations’ and ‘lunar orbits’ — are largely arbitrary, and would change depending on where you’re based relative to other things. A slightly trickier question, though, is how do we know that one second is the same length as every other second? Maybe if there was an ‘outside perspective’ of time, one minute could last *this* long, and another minute could last *thiiiiiiiiiiis* long, but they feel the same length to us because one of them was squished together with us inside of it. Each one of them contains a minute’s worth of ‘stuff’, but just because they *feel* the same length to us, how do we know they actually *are* from some external and objective reality?
Weirdly, this isn’t as crazy as it sounds. [*Time dilation*](https://en.wikipedia.org/wiki/Time_dilation) is an effect of relativity, in which — from an ELI5 perspective — a second as perceived by one person might be a very different length to a second as perceived by a different person depending on how fast they’re going. You can define a second as the time it takes a pendulum of a certain length to swing once, and that time will be the same for both Person A and Person B… but Person A’s pendulum might swing dozens or hundreds of times more often than Person B’s pendulum from Person A’s perspective during the same interval, depending on their relative speeds. (Relativity is complicated, and things get very unintuitive very quickly.) We can calculate these values consistently and show them to be real — in fact, things like GPS satellites *depend* on us being able to calculate these values consistently — but they’re still different from the point of view of each observer. So how can we define *time* at all, if it’s not the same everywhere? If time depends on how fast you’re moving, how do we know that it actually even exists at all?
One way is to think about *time* not in terms of measuring it, but in terms of whether we can detect time ‘happening’ in the first place. (Now we’re not interested in whether a second is a second, but whether a second is *anything meaningful at all*.) In that sense, what we call ‘time’ is really just a measurement of *change*. (After all, the only way to detect the passage of time is to note how things vary from one point to the next. You can think of it like taking two photos; if you can’t detect any changes between the photos, how do you know that it’s two photos taken seconds or minutes or weeks or years apart, rather than just two copies of the same photo?) One of these is the principle of *cause and effect*, namely that if an action A causes an effect B, A must have happened before (or rather, at an earlier time than) B. One way to think of ‘time’, then, is as a measurement of causal effect. Time *must* be progressing, because change keeps happening, and because change happens in one direction only, the value we assign to ‘time’ — perhaps thought of as the countdown that has progressed from the start of everything to what we call ‘now’ — has to keep increasing. The classic example is unscrambling an egg: from our perspective, the unscrambled egg must always come before the scrambled egg, and so it can be seen that time can only act in one direction; as a result, A must predate B. (The slightly more scientific formation of this thought is that [entropy](https://en.wikipedia.org/wiki/Entropy) — the level of ‘disorder’ in a system — cannot decrease over time without putting work into the system; just as you can’t expect the milk you stirred into your coffee to randomly unstir itself, you can’t undo the natural processes that split apart an atom by radioactive decay. State A comes before State B, and so if you could line up all of those necessary A-before-B states from the beginning of time to now, you’d end up with what is effectively a timeline that shows a progression. You might not know how long it took between each *step* of that timeline, but you’d still be able to show that progression was happening.)
Again, this is a *very* ELI5 explanation, but [this is a pretty good rundown of why figuring out whether time is ‘real’ is a bigger — and smarter — question than it first sounds.](https://bigthink.com/starts-with-a-bang/does-time-exist-182965/) The short version is that *time* can be definitely said to exist, at least according to our current understanding; it’s just the specific measurements that are fiddly and weird and often pretty arbitrary.
First off, the current theory of time, as I understand it (and let’s be clear, it is, at best, a vague understanding) is that time is basically a fourth dimension to space. It’s just a measurement. Like you can describe an object by its length, width, height, and time. That’s why you sometimes hear people referring to ‘space/time’ So, specifically, time only exists where there is space. So that the big bang wasn’t just when everything came into existence, but when time came into existence, because before that, there wasn’t space for space/time to measure.
So time isnt infinite, exactly, it’s just a measurement tool for defining something when you have something that needs to be defined.
And that’s the key. It’s a measurement. It isn’t a thing. Like a shelf isn’t composed of six inches of width, the width is just how we organize the aspects of the existing piece of wood.
Does that make sense?
To add to all the answers here, time is actually proposed to be a type of physical unit as well as a measurement of passing events.
“Time has been called a river that carries forward every thing until it sinks in its waves, but time is not a river and it does not flow. Physical reality is a process and it can be called the river of existence. This river does not need time or any other force beyond itself to “carry” it and to be what it is: a process. Time is not part of that process: it is not an ingredient of physical reality and it does not flow. Time is the artificial bank in relation to which the river of physical reality flows. Time is an element of our language by means of which we speak about physical reality and its change: it is one of the basic elements of the conceptual system by means of which we express our perception and understanding of the physical reality in which we dwell and of which we are part.” Radovan 2011
https://www.researchgate.net/publication/262108573_Time_and_the_river_of_existence
Yes and no. Time exists as a property of space but it doesn’t exist in the same way a block of cheese exists. Time is the property of how things move through space in relation to each other.
And, more importantly, what is clocks?
Time can be described as one of two things:
A) The difference between one from of reality to the next.
B) versions the universe lined up from one moment to the next
Are you familiar with George Carlin’s thoughts on the topic from some time in the 1970s.? Might be helpful answering it from a philosophical point of view.
>That’s not proof of time itself.
Okay, but live long enough to watch your body do its slow decomposition thing and, well, yeah. Corporeal things exist within a limited amount of linear time.
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