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Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

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Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#41

Post by _8j50 »

pmoriarty wrote: post #26
_8j50 wrote: post #20

I think I'm a simpleton because I could never imagine time being it's own thing. I see time as simply the amount of change in reality we can perceptually sample. Much like how an object in motion will continue in it's motion until it meets resistance,reality in my opinion is in continuous motion that has yet to meet resistance. Time (imo)is our measure of this change divided by our ability to sample it(where this abi…

"I see time as simply the amount of change in reality we can perceptually sample." So if there was no one to perceive the change, there'd be no time? Also, what is change?

Change is modification of a physhical attribute for an object. Without someone to perceive there would be change but no time.

Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#42

Post by pmoriarty »

_8j50 wrote: post #41
pmoriarty wrote: post #26

Earlier quoted context omitted.

"I see time as simply the amount of change in reality we can perceptually sample." So if there was no one to perceive the change, there'd be no time? Also, what is change?

Change is modification of a physhical attribute for an object. Without someone to perceive there would be change but no time.

"Change is modification of a physhical attribute for an object."

This sounds like a circular definition because "modification" is a synonym for "change".

Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#43

Post by _8j50 »

gowld wrote: post #25
_8j50 wrote: post #20

I think I'm a simpleton because I could never imagine time being it's own thing. I see time as simply the amount of change in reality we can perceptually sample. Much like how an object in motion will continue in it's motion until it meets resistance,reality in my opinion is in continuous motion that has yet to meet resistance. Time (imo)is our measure of this change divided by our ability to sample it(where this abi…

Sounds good. Next, please define "change", and explain why or how "change" exists and is detectable by humans. That's what Rovelli is investigating/theorizing about.

Yes but they are investigating our relative perception of the change. It's like studying astronomy without considering the fact that the stars we perceive in the sky is just our perception of how they looked like in the past. We distinguish how things are now from what we can perceive by measuring light and EMR. Why can't we at least consider the possibility that our perception of change might be different from the actual nature and attributes of this change?

Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#44

Post by redial »

pmoriarty wrote: post #36
redial wrote: post #34

Earlier quoted context omitted.

I was talking about the royal you: we. But more importantly, "when" the question was first asked doesn't change the nature of the question. Sure, you (we) can ask it, but it is no more insightful that the myriad of other metaphysical questions that have been asked through history that will never be answered because they lack a fundamental grounding in the shared experience we call "reality". Are there any blue reds?…

"Are there any blue reds? We can spend a millennia thinking about it." It's pretty obvious that you can have blue reds: they're called purples or violets. Just squeeze some blue out of a tube of paint, and then some red, mix them together and you get a blue red. You can also have a black white: it's called gray. Anyway, I'd agree that one could ask any number of metaphysical questions, but it could be argued that onl…

Violet is not blue and it is also not red. I'm not asking for a bluish red but for a 100% blue color that it is also red.

You are misusing the language, or rather I am in this case, to ask a paradoxical question. Where are all the cat dogs? This is a never ending game because we don't agree on the language. This is exactly the realm of metaphysics.

And greatness is in the eye of the beholder. To me greatness could be quantified by how much progress has been made in answering the question. After a thousand years and possibly millions of lives wasted trying to answer "is there existence before this life?" we are not one single iota closer to an answer. That implies a pretty bad question that is not grounded in reality, or at the very least not "grammatically" grounded in reality.

Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#45

Post by _8j50 »

pmoriarty wrote: post #42
_8j50 wrote: post #41

Earlier quoted context omitted.

Change is modification of a physhical attribute for an object. Without someone to perceive there would be change but no time.

"Change is modification of a physhical attribute for an object." This sounds like a circular definition because "modification" is a synonym for "change".

An object's property had a specific value. That value became different.

Can we agree on that definition?

Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#46

Post by _8j50 »

andrepd wrote: post #37
_8j50 wrote: post #20

I think I'm a simpleton because I could never imagine time being it's own thing. I see time as simply the amount of change in reality we can perceptually sample. Much like how an object in motion will continue in it's motion until it meets resistance,reality in my opinion is in continuous motion that has yet to meet resistance. Time (imo)is our measure of this change divided by our ability to sample it(where this abi…

Right, however relativity tells us that time is an actual, physical thing that can be affected by and affect matter.

I am not informed well enough to answer you but can you point me in the right direction on anything that associates time being a physhical matter? How would relativity change if one looks at time as "perceived universal change'?

Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#47

Post by andrepd »

trevyn wrote: post #6
pmoriarty wrote: post #2

Not to nitpick, but I'm not sure the nature of time is so indisputably the greatest remaining mystery. The nature of consciousness, life, and death can all certainly give it a run for its money. Incidentally, would anyone happen to have a direct link to a version of this article that could be read without enabling javascript?

Consciousness: Thomas Metzinger’s “The Ego Tunnel” Life and death: Molecular biology

The way you curtly replied makes you think that the question is settled, perhaps even trivial, when in reality regarding consciousness that is but one person's thought on an issue where nobody can claim to have an understanding, let alone an answer, and regarding molecular biology there is still much, much to learn.

Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#48

Post by andrepd »

simondedalus wrote: post #9
everdev wrote: post #4

Earlier quoted context omitted.

"Nature of existence" probably encapsulates all of those ideas including time as time seems to be required for a creation/destruction type event.

nature of consciousness is the biggest one IMO, precisely because it doesn't appear to be captured by "nature of existence." we have good physical/mathematical models on hand re: causation, such that we can at least start hypothesizing about what change is, where the universe came from, what if anything differentiates life from other motion, etc. but consciousness is so categorically different that we can't even star…

This is very much how I think about this issue. It's a problem of a completely different class than almost anything else.

Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#49

Post by andrepd »

_8j50 wrote: post #46
andrepd wrote: post #37

Earlier quoted context omitted.

Right, however relativity tells us that time is an actual, physical thing that can be affected by and affect matter.

I am not informed well enough to answer you but can you point me in the right direction on anything that associates time being a physhical matter? How would relativity change if one looks at time as "perceived universal change'?

I'm not sure what I would recommend as an introduction to relativity. If you're mathematically minded and have a lot of time on your hands, and actually want to learn the physics, a superb book is "Spacetime and Geometry" by Sean Carrol. As for a layman introduction, I'm not sure what to recommend.

As succinctly as I can put it, in our current understanding spacetime is a 4-dimensional space whose curvature is related to the local energy-momentum content. In turn, the motion of particles in freefall is dictated by this curvature.

Re: Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time

#50

Post by pmoriarty »

_8j50 wrote: post #45
pmoriarty wrote: post #42

Earlier quoted context omitted.

"Change is modification of a physhical attribute for an object." This sounds like a circular definition because "modification" is a synonym for "change".

An object's property had a specific value. That value became different. Can we agree on that definition?

"An object's property had a specific value. That value became different."

How is something that's different different from something that's changed? It sounds like it's one and the same to me.

Also, you used the word "became". That word has temporal connotations. So if you define change in terms of time, you can't then go on to define time in terms of change without it being another circular definition.

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