How do we know time exists and isn’t just an imaginary measurement?


How do we know time exists and isn’t just an imaginary measurement?

In: Physics

We don’t, not in a “we are absolutely sure and can prove it” sort of way. What we do know is that we seem to have both a personal and shared experience of time, and (at least at the macro or emergent level) our physical laws incorporate time. Ultimately, that’s about it. There’s nothing we can touch or point to and say, “See that? That right there is ‘time’.”

But go one step further, how do we know ANYTHING exists and isn’t imaginary beyond our personal and apparently shared experiences? And ultimately even if nothing “exists” independent of our/your imagining of it, isn’t that still a form of existence? My imagination exists, my thoughts exist, maybe that’s all there is?

The simple answer is we don’t. We cannot prove the concept of time at all, but nothing makes sense without it do we fudge stuff to apply time to science.

At quantum levels time is even excluded as a variable in equations. There was even a chap called Rovelli who published articles about how time does not exist at all and its merely human perception.

However, from a practical perspective try and spend a week without acknowledging time as a thing and you’ll come unstuck pretty fast.

It *is* an imaginary measurement, all measurements are. They’re arbitrary words we assigned to concepts so that we can communicate from one person to another, “Yes, I am referring to this specific amount of this specific thing.” Inches, pounds, minutes, miles, they don’t “exist” on their own. It’s language as tools.

This question is often asked as a thought exercise in philosophy classes as well because we can’t prove it even though we all live by the same convention that we think of as time.

If you’re talking specifically for physics, then “time”, as in a direction of development, is an equivalence to both causality and to the limited (non-infinite) speed of light. Because information can only travel at a fixed speed, and we observe that things do in fact travel, this necessitates that events have an “order” (although that order itself is subjective).

We can then use thermodynamics to define the positive direction of time to be the direction of increasing entropy, which we use because that also coincides with how we mentally interpret time.

Time exists because things change. If you roll a ball down a ramp it changes position over time. It can only do that if there is time.

The measurement of time is made up. We just picked something conveient that everyone could agree on so when we talk about time everyone has the same idea.

At first it was just dividing the time it takes for the Earth to spin. Now it’s based on a something that happens very quickly to an atom that we can count.

There is both a subjective and objective elements. It is not an illusion. It is not a flow of continuous ‘ now’s ‘ although there is a real ‘now’s in time.

See “ New Advent- Catholic Encyclopedia “. Go to letter ‘T’ and scroll down to “ Time “ Read it for sure!

The measure of motion is time. No one has definition of time but we know a lot about the nature of time. Time as a duration is the continued existence of motion. Time is also a measure the definition of which is the number of movement in respect of before and after. Time and motion differ. Motion belongs to the thing that is moving and can be fast or slow. Time however is everywhere and is not fast or slow.

Time is intimately connected with succession. Time is a measure of movement and that which is not in time is immobile. And time is not the same as movement since it is its measure. The words ‘ in respect of before and after ‘ indicate that time does not apply to movement precisely as movement, but in so far as it is successive. Today, in nature, there is no known movement that is absolutely uniform. In a wide sense past, present, and future are parts of time.

The duration of motion is not a reality found in nature apart from the mind. It is our mind, endowed with memory, which gives unity to motion, and to the duration of motion, as a whole. Further, its duration is the foundation of time as a measure, since only in so far as it is an enduring whole does it lend itself to measurement.

In so far as time exists, it does so by reason of the present instant, which is not a part of time. It is present only in so far as it is considered by the mind in relation to past and future but it clearly does not make the past or present exist.

So neither time as a duration nor as a measure exist or are real apart from the mind. This should not blind us to the fact that there is an element of time which has an extra-mental existence, viz. the indivisible of time, the instant.

The very totality of time is comprehended through the ordering of the soul which enumerates before and after in motion. Taken as a whole duration or measure exists in the mind only.

“ Modern Thomistic Philosophy “ R.P. Phillips.

I have read on Quota time and entropy have nothing to do with one another. Furthermore, to a physicist time is what a clock measures. Physicists use time but I don’t think they really have any idea what it is no matter how many books they write. It is a philosophical measure. Because they consider the arrow of time and wonder why time goes forward and are confused about it does not mean others are not more than competent to discuss this.