What is time?

The question came up in the one philosophy class I ever took way back when, and no one seemed to know. Not even the professor.

I’m talking about that whatever-it-is continuum which perhaps started when the Big Bang started.

It’s the thing that stops everything happening all at once.

Best explanation I’ve heard (and it might even be right, who knows), was offered by scotth in this thread (which is woprth reading just for the insanity of it all):

Or, in other words, our universe is like the wave of motion in a chain of toppling dominoes - it’s not the dominoes themselves, it’s just an effect of their falling in sequence, each one triggering the next.

The link didn’t work. I’d like to read the thread, though.


John Wheeler.

Thanks. I checked him out at Wiki, noting the books he wrote and so on.

“In 1979 Wheeler spoke to the American Association for the Advancement of Science (AAAS), asking them to expel parapsychology, which had been admitted ten years earlier at the request of Margaret Mead. He called parapsychology a pseudoscience (Gardner 1981:185ff). His move was turned down and the Parapsychological Association remained a member of the AAAS.”

Is parapsychology still in the AAAS?

The Parapsychological Association is still an affiliate of the AAAS (which is what Wheeler was objecting to).

No Time Cube references?
I’m shocked.

No, you’re educated stupid.

Mass and energy exist in the fabric of space.
The fabric of space, at present, is undefined.
A given distribution is a moment in time.
An alternate distribution is a different moment in time.
The flow of time results from the fact that changes in the distribution of mass-energy in the matrix of space follow mathematically describable patterns.
There is a debate, in general, about whether this distribution changes in discrete quanta, or in a continuum.
Right now the quantum approach seems to hold sway.

I think it’s the agency that sorts causes before effects, and it only appears to be something flowing because our brains (whose function is to manipulate cause and effect) manage things with constructs we “think about”. That is, since the brain manages time for us, when we use that same brain to think about the nature of time itself, it seems like “stuff”.

I was going to reply with: Well, if you tell us how you’d define space, then we can continue from there.

But Chief Pedant beat me to it.

For a thermodynamicist, it’s the difference between which a close system is more orderly and when it becomes less orderly, or more primitively, the difference between the state when two ends of a box are at much different temperatures and when they’re closer to equilibrium. For the quantum mechanicist, it’s all about the spread of the probability distribution of the momentum and location (or two other comingled factors) of a particle. And for a child, it’s the difference between running around freely in the backyard and being forced by beastly creatures pretending to be parents to lie in bed and stare at the ceiling.

It’s a useful metric to judge the rate or effect of other actions, but only in a local reference frame. Beyond that, there’s no good answer to your question; certainly not from the Philosophy department.


It’s been a while since I read A Breif History of Time by Stephen Hawking, but IIRC he basically disproves the laypersons conception of time as a strict unit of measure. I couldn’t find a link with quotes, nor do I own the book, but I think it’s a great book for anyone to own regardless of their level of scientific knowledge.

On the contrary, there are several good answers (or at least, thoughts potentially contributing to a good answer) from the Philosophy department. For the curious, some of them may be contained at the following link: http://plato.stanford.edu/entries/time/



It’s what you measure with a clock.

Think of this aspect of time: relations of events to each other

Time allows things to not happen all at once. For example, in the news, the highway bridge collapse, the mine incident, the New York City tornado - all happened on roughly the same day. Of course, there is no reason why they could not happen on different days. The point is that there is a finite number of ‘events’ that don’t happen on the same day…say, a million events, similar to the bridge collapse or the tornado, could not happen on the same day.

But is that a function of time or mere probability? I wonder if John Wheeler fired off his famous statement in jest - “Time keeps things from happening all at once” (or words to that effect).

Time — whatever it is — doesn’t DO anything. Time is just there and in some baffllingly impassive way, it enables shit to happen totally independent of it. Except that if time stopped, all events would stop, too.

Time somehow enables change, but doesn’t control change; it doesn’t limit how many events that can happen in a given span.

I think.

Time is 4:16 PM, Central Daylight, at posting

Centimeters measure the physical distance between objects. Likewise, seconds measure the temporal distance between events. Time is only another dimension, just one that we perceive differently.

If you really want to twist your noodle, think about the fact that inside a black hole, timelike dimensions become spacelike dimensions and vice versa.