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The closer we look at time, the stranger it gets

sciencefocus.com

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Re: The closer we look at time, the stranger it gets

#101

Post by euroderf »

benchly wrote: post #62
My_Name wrote: post #55

They nearly have it in the article but don't take the next step, which is to realise that time is gravity. We are falling towards the future at the speed of causality. You can slow your experience of that by travelling really fast, or by being near something with a large gravity. Quantum particles can simply ignore gravity and time while we are forced to feel their effects due to our size, like a mote of dust can ign…

You might be interested in The Order of Time by Carlo Ravelli. Time and gravity are certainly linked, but from what I took away from the book (which is a lot to digest, even as non-mathy as it tries to be) is that Time is really heat. Heat moves only from hot to cold, dispersing in some entropic fashion as we move toward the final state of the universe, but in the meantime we can measure that time/heat "flows" at dif…

Entropy! What interests me is that particle behavior is reversible at micro scale, but then activity becomes irreversible "above" some point.

Re: The closer we look at time, the stranger it gets

#102

Post by IAmBroom »

grishka wrote: post #44

There's another inscrutable mystery in physics, the nature of consciousness. Time might as well be an artifact of that . I'm surprised this article doesn't mention this possibility. Here's an interesting lecture about it: https://www.youtube.com/watch?v=YusrOYGAhqM

The first problem with the nature of consciousness is describing what you mean by it. Try, and I guarantee you that someone will find a sponge, Apple product, or bathroom slipper that meets that definition.

Electro-magnetic radiation, on the other hands, is highly describable in precise, testable, repeatable terms.

When you can state Maxwell's Laws of Consciousness, we'll talk. And rename them "Grishka's".

Re: The closer we look at time, the stranger it gets

#103

Post by sbuttgereit »

ndsipa_pomu wrote: post #35

One problem that I have with trying to understand "time" is that we can't measure how quickly it "flows" or at least how quickly we travel through it.

I guess I have to ask what more you're looking for, perhaps hoping for, than: 1 second per second?

Re: The closer we look at time, the stranger it gets

#104

Post by euroderf »

sigmoid10 wrote: post #61
My_Name wrote: post #55

They nearly have it in the article but don't take the next step, which is to realise that time is gravity. We are falling towards the future at the speed of causality. You can slow your experience of that by travelling really fast, or by being near something with a large gravity. Quantum particles can simply ignore gravity and time while we are forced to feel their effects due to our size, like a mote of dust can ign…

Well, almost. Because these usual descriptions you give here are approximations. Yes, to the first order, gravity is expressed as the effect on time in general relativity. So you could describe how planets move simply by calculating how they move differently through time. But in the full picture, the way you move through space or near strong gravitational fields also influences your experience of space itself. So the…

> The ultimate question is, does spacetime itself also come quantized when you look close enough?

Isn't there some sort of "quantum foam" ? So it's going to be difficult to define a metric ?

Re: The closer we look at time, the stranger it gets

#105

Post by oersted »

_bernd wrote: post #94
oersted wrote: post #92

Earlier quoted context omitted.

Things happen, some things happen before other things. We count time by using clocks, they tick at regular rates with respect to other things happening. If a clock is in a frame of faster time, it will tick faster, its ticks will happen before, than an identical clock in a frame of slower time. That’s how I see time, it is the ordering of physical events, which we can trivially observe. You keep trying to explain tim…

> That’s how I see time, it is the ordering of physical events, which we can trivially observe. My teacher explained it in a similar way. Time passes when we can observe change. If there is no change then we can not measure time. Like with the heat death of the universe. At that time (lol) no more time would "happening".

What I ask myself is: is time purely the ordering of things that happen, or do gaps where there is potential for something to happen also count?

Let's assume for simplicity that time is a discrete dimension, which it might be. Then there would be a measure of distance of how many ticks of potential events there are between two actual events, even if nothing happened in between. Or maybe that's not the case and it's more of a directed graph defining the partial ordering of actual events.

Not sure if we could measure that in any case, we always need some kind of actually ticking clock, and it's not like we can isolate a period of time where nothing happens globally, unless its in a simulation. Just like weird things happen at quantum scale, I'm sure weird things happen at small enough time scales where there's really nothing between one event and the next, and there's no good way to determine how far a part they are.

Re: The closer we look at time, the stranger it gets

#106

Post by euroderf »

grishka wrote: post #44

There's another inscrutable mystery in physics, the nature of consciousness. Time might as well be an artifact of that . I'm surprised this article doesn't mention this possibility. Here's an interesting lecture about it: https://www.youtube.com/watch?v=YusrOYGAhqM

> consciousness. Time might as well be an artifact of that.

Psychedelics can remove the sensation of time passing. But they are also modifying the experience of "consciousness" itself.

Re: The closer we look at time, the stranger it gets

#108

Post by sbuttgereit »

I think I like Tim Maudlin's approach to the question. Time isn't all that mysterious: it's simply fundamental meaning it cannot be explained has being the sum of some things more fundamental. The argument is that's where the difficulty lies for many is they want to express time as though it's a composite, and it just isn't. So the best you can do is explain time by referencing those other aspects of existence which incorporate time.

Here's a much longer take from Tim Maudlin, "Tim Maudlin: A Masterclass on the Philosophy of Time" (https://youtu.be/3riyyEmWwoY?si=9aI-bETWcNpdjMW9), Tim Maudlin is Professor of Philosophy at NYU and Founder and Director of the John Bell Institute for the Foundations of Physics. The podcast is Robinson Erhardt's.

Re: The closer we look at time, the stranger it gets

#110

Post by sigmoid10 »

euroderf wrote: post #104
sigmoid10 wrote: post #61

Earlier quoted context omitted.

Well, almost. Because these usual descriptions you give here are approximations. Yes, to the first order, gravity is expressed as the effect on time in general relativity. So you could describe how planets move simply by calculating how they move differently through time. But in the full picture, the way you move through space or near strong gravitational fields also influences your experience of space itself. So the…

> The ultimate question is, does spacetime itself also come quantized when you look close enough? Isn't there some sort of "quantum foam" ? So it's going to be difficult to define a metric ?

The difficulty is turning the metric tensor into a quantum field like object. Apart from being incredibly complicated, because the field interacts with itself and all other fields, there are a bunch of mathematical quirks that prevent this from working out like it does in all our usual quantum field theories. Until someone comes along with a theory where all this works and still returns our normal physics in the low energy limit, noone can say what might really happen at that level. Maybe spacetime isn't quantizable because it fundamentally isn't quantum. Maybe it doesn't even exist at those length scales and what we perceive as space and time are emergent properties of some yet to be understood quantum process.
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