No need to spend much time on this one. Pun intended! Time is not a dimension of reality. Time is just identical with motion. We can prove this using a simple thought experiment:

Imagine that everything stopped moving.

Can you think of a single scientifically or artistically relevant way in which there could still be time? If so, bring it into the discussion.

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Obviously if the universe did not change, then there length of the time dimension of the universe is indistinguishable from zero. It seems fair to say that in a timeless universe, there is no time dimension.

It is not clear what you mean by “time is identical with motion.” This doesn’t seem diametrically opposed to the notion that time is a dimension of the universe, since motion occurs within geometric dimensions.

Please explain two phenomenon in the context of your statement:

1.Time dilation: i.e. Objects which are not in the observer’s inertial frame appear to experience time more slowly.

2.If time is not a dimension, then it is difficult to understand how the direction of time can differ for two observers and general relativity (a geometric theory based on four dimensional space-time vectors) does not make sense. If the difference in the direction of time does not cause the apparent acceleration in a gravity well, what does?

A note on language: Regardless of whether or not you consider time to be a geometric dimension of the universe it is still a dimension. That is, when specifying an event, adding a time stamp gives additional information which is not contained in a purely geometric coordinate system. That is, I can not only say I ate lunch today at 38° 45′ N, 90° 23′ W. I can add that I ate lunch at 12:31 and you get more information.

Now, in your example where nothing in the universe ever changes, then specifying a time coordinate does not add additional information, since all locations in space are eternally the same.

Dearest urdumb:

Are you implying that anything that adds more information is a dimension? This seems problematic, as this would imply there are penultimate dimensions! (See https://sciencedefeated.wordpress.com/2008/10/21/infinity-part-one/) I cannot only say I ate lunch today at 38° 45′ N, 90° 23′ W, I can add that I ate a delicious reuben sandwich and met with my cousin. But clearly, What I Eat and Who I Eat With aren’t dimensions.

*sigh*

Dear mr.,

Yes and no.

First remember, we are not referring to geometric dimensions, as I clearly stated.

But, rather time can be a useful part of a coordinate system to specify an event. In principle there isn’t anything innately special about the information which forms a coordinate system, but anything approaching a useful a coordinate system must have three properties. It must have be (a) specified for all events, (b) differs between events and (c) produce a unique ordering of events.

(that is have an axis or direction.)

c) is likely the most slippery concept. Essential it means that we must be able to construct a function which sorts events into one and only one configuration. Linear ordering are easy to see, but a closed ordering is also acceptable. We can arrange the colors in a color wheel that has no edge, but every color can be unambiguously mapped onto the color wheel. Of course, not all events have a defined color, so color cannot be used as a coordinate system in most contexts.

You might enjoy Christoph Schiller’s textbook Motion Mountain which goes into the nature of motion in a bit more depth. A downloadable copy can be found at http://www.motionmountain.net/

Thanks for the recommendation!

Can I still play?

If we could stop

allmotion (down to elementary particles) in (for instance) a one meter box, then an observer would note that nothing changed within the box but that time still passed, and that time is real and distinct from motion.If the observer were also inside the box (maybe a bigger box) then the observer stops along with everything else. From this perspective time and motion are the same. Perhaps this is what you intended?

I believe

Urdumbis correct that physics contradicts this, but I don’t recall physics being invited to play this game.Dan,

In the very insightful thought experiment you describe, I think my timeless ontology still applies. What the outside observer would notice is actually

justthat nothing is moving. The only sense in which the outside observer would note that time continued is that motion continued. I think this is more parsimonious.NS

Timeless Ontology– Very good!The outside observer sees more than

justno movement, they see that the box and its contents continue to exist (a reality) over time even though nothing is moving in the box. The observer inside the box notices nothing at all, of course.My argument requires imposing a frame of reference beyond the thought experiment you originally stated, which may not be playing fair. Without this frame of reference, I am forced to concede your point.

Thanks for taking the time to revisit this.

without memory, there would be no time. therefore, it’s a perception. you are correct. time is related to motion

And how would this affect us?

And more importantly, how can this help me take over the world?