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The closer we look at time, the stranger it gets

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

#111

Post by grebc »

sbuttgereit wrote: post #108

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…

I like Tim, his arguments come across as an honest attempt to answer real questions. I feel as if the current crop of physicists look down on things that appear too simplistic.

Their math give an answer with artefacts they can’t match to reality so they keep probing the outliers of these absolutely bonkers ideas, and rabbit holes keep getting deeper & weirder.

Time doesn’t exist. Do the people writing this garbage live in a vacuum? Is it AI slop?

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

#112

Post by OkayPhysicist »

flowerthoughts wrote: post #75
MaxikCZ wrote: post #38

Earlier quoted context omitted.

The fact that at speed of light time stops is just so bonkers to me. A photon is, from its point of reference, at the point of creation and at the point of destination at the same "time". Its literally seeing both parts of the universe at the same time, and since its traveled some distance over that time it cannot perceive, its essentially connecting 2 points in spacetime. If I understand it correctly, every photon e…

Layman thoughts: The photon cannot experience the universe as it passes through it instantly. It seems to me the universal speed limit creates an observability barrier that is really fascinating. The question is what are we missing, because we're zipping through _something_ at the speed of light relative to it. Lately, I've been wondering what evidence we have that the speed of the photon/light is really the universa…

It does, though. Because it's massless, it either needs to be going at max speed or zero speed. And a zero-mass, zero-energy object is a pretty good working definition for "nothing", so photons must travel at the speed of causality, thus making it "the speed of light".

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

#113

Post by grebc »

IAmBroom wrote: post #99
grishka wrote: post #78

Earlier quoted context omitted.

I was downvoted for saying that our cosmological model might be wrong because "dark matter" sounds like a crutch. Now JWST has collected enough evidence that it might, in fact, be wrong.

Dark matter absolutely is a crutch. It's "dark" in the sense that the (fabled) Dark Ages were dark. They didn't have more cloud cover then. And dark matter is 'dark' as in 'inobservable, except by gravitational attraction'. So we admit it might not even be "matter" by any definition we have; it's just what we're calling this invisible, untouchable, silent elephant in the room. That is very heavy. And might not be an…

Honestly, just saying the maths doesn’t always work is much more approachable than dark/invisible matter.

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

#114

Post by flowerthoughts »

OkayPhysicist wrote: post #112
flowerthoughts wrote: post #75

Earlier quoted context omitted.

Layman thoughts: The photon cannot experience the universe as it passes through it instantly. It seems to me the universal speed limit creates an observability barrier that is really fascinating. The question is what are we missing, because we're zipping through _something_ at the speed of light relative to it. Lately, I've been wondering what evidence we have that the speed of the photon/light is really the universa…

It does, though. Because it's massless, it either needs to be going at max speed or zero speed. And a zero-mass, zero-energy object is a pretty good working definition for "nothing", so photons must travel at the speed of causality, thus making it "the speed of light".

Thanks for the reply. That's still a theoretical reasoning. "Based on our current _models_, it must follow that c=c'." I can accept that. I guess part of a wider theoretical answer is that a photon is just an interaction in quantum fields, and that indicates there's nothing special about a photon that could limit its speed (as you imply.) What you're saying makes me think I should be looking for impediments for attaining speed, and it seems only (inertial) mass is that thing.

My question is if this part of the model has been validated experimentally somehow.

BTW, it seems odd calling a photon a zero-energy object.

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

#115

Post by luc4sdreyer »

grebc wrote: post #111
sbuttgereit wrote: post #108

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…

I like Tim, his arguments come across as an honest attempt to answer real questions. I feel as if the current crop of physicists look down on things that appear too simplistic. Their math give an answer with artefacts they can’t match to reality so they keep probing the outliers of these absolutely bonkers ideas, and rabbit holes keep getting deeper & weirder. Time doesn’t exist. Do the people writing this garbage li…

> Time doesn’t exist. Do the people writing this garbage live in a vacuum? Is it AI slop?

Maybe don't dismiss an idea as garbage before trying to understand it.

One of the ideas here is that time is an emergent phenomenon, like how temperature and gas pressure seem real at a macroscopic level, but disappear once you look closer. They simply describe the average kinetic energy of all the molecules in the area.

The _hypothesis_ is that time could be similar.

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

#116

Post by OkayPhysicist »

flowerthoughts wrote: post #114
OkayPhysicist wrote: post #112

Earlier quoted context omitted.

It does, though. Because it's massless, it either needs to be going at max speed or zero speed. And a zero-mass, zero-energy object is a pretty good working definition for "nothing", so photons must travel at the speed of causality, thus making it "the speed of light".

Thanks for the reply. That's still a theoretical reasoning. "Based on our current _models_, it must follow that c=c'." I can accept that. I guess part of a wider theoretical answer is that a photon is just an interaction in quantum fields, and that indicates there's nothing special about a photon that could limit its speed (as you imply.) What you're saying makes me think I should be looking for impediments for attai…

Photons are zero-mass, some energy. (and thus moving at max speed). I was trying to convey that the only way for something to be massless and not moving at the speed of light would be for the massless object to be stationary (and thus zero energy).

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

#117

Post by user3939382 »

IAmBroom wrote: post #98
user3939382 wrote: post #47

I have a solution that addresses this. Will publish soon, it’s a slow process.

Ooh, do the unified-field thing next!

You are everything that’s wrong with STEM. Sarcastic and angry with 0 contribution.

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

#118

Post by MaxikCZ »

mr_mitm wrote: post #74
kburman wrote: post #59

Earlier quoted context omitted.

Have a question related to this, if a photon has zero proper time between emission and absorption, how should I think about the influence of later-created photons or fields on it? In our frame, we can interact with a photon long after it's emitted send it through a filter, bounce it off a mirror, measure it, etc. But from the photon's own “no proper time” perspective, does it make sense to ask how something created a…

The photon doesn't have an inertial frame of reference precisely because it's moving at the speed of light, so it doesn't have a perspective. It's a (quantized) wave in the electromagnetic field. The closer you get to the speed of light, the closer the proper time of the journey goes to zero, but actually taking the limit does not make sense physically.

I wonder if Photon doesnt have an inertial frame of reference - from our point of view.

Like, from our point of view, we assume that from photons point of view it has no perspective.

But maybe we are limited by our spacetime, where photon goes trough our universe in an instant, and continues to pierce infinite universes over its non-zero frame of reference.

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

#119

Post by alex77456 »

hnfong wrote: post #93
alex77456 wrote: post #12

Earlier quoted context omitted.

If you consider a person, their brain in particular, flowing backwards in time, the brain becomes a prediction tool. Events-memories (neural connections) appear out of nowhere (from the state of being 'forgotten' in the forward time flow) then completely disappear when the corresponding event happens, annihilating its 'predicting' memory.

The brain does want to predict (in fact I think that's what it's suppose to do), the problem is that the Earth is rather chaotic and unpredictable. If you subject a brain-like neural network to watch planets and stars orbiting around each other and rewarding it for getting things right, it will likely do quite well.

Not that kind of predict. And this reverse-time brain instantly forgets things it saw for the last time.

Consider a black box. A person opens it, sees a dice with a number, closes it. In our version of the time flow, the person finds out there's a dice and remembers it. In the 'reverse time' persons brain, they would know they would open the black box and know which number they will see. Then they will close it and completely forget what was inside forever.

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