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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

#21

Post by [deleted] »

ricardobeat wrote: post #13
slyfox125 wrote: post #9

We understand "time" in the context that we must: to subsist in order to procreate. The extent it exists outside of our own perception as we imagine it does, is debatable. Ultimately, time is our sensory interpretation of the world around us to facilitate our survival and thus, we may never make sense of it outside the constraints it exists within.

We know empirically that time only flows in one direction, it can’t be described as just a perception. You’d have had at least the tiniest of evidence that time sometimes flows backwards.

[deleted]

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

#22

Post by jrnng »

ricardobeat wrote: post #13
slyfox125 wrote: post #9

We understand "time" in the context that we must: to subsist in order to procreate. The extent it exists outside of our own perception as we imagine it does, is debatable. Ultimately, time is our sensory interpretation of the world around us to facilitate our survival and thus, we may never make sense of it outside the constraints it exists within.

We know empirically that time only flows in one direction, it can’t be described as just a perception. You’d have had at least the tiniest of evidence that time sometimes flows backwards.

What if it's circular, or cyclical?

We don't know empirically what came before the beginning.

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

#23

Post by actionfromafar »

robot-wrangler wrote: post #15

IANACosmologist, but in for a penny, in for a pound. If one accepts weirdness along the lines of extra spatial dimensions and mathematical singularities made physical, why not throw in a few extra dimensions for time or why not have imaginary time (in Hawking's sense)? > One might think this means that imaginary numbers are just a mathematical game having nothing to do with the real world. From the viewpoint of posit…

"describe our observations of the universe"

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

#24

Post by russdill »

dotancohen wrote: post #5

> Combining quantum mechanics and General Relativity is all well and good, but there‘s one key mystery it doesn’t address: why does time only seem to flow in one direction? Could the problem just be with us? When time flows backwards, we lose the ability to perceive the events that came after the "current" event. As it flows forward again, we have more time in our context window. We are able to perceive only those ev…

For the "canonical" physics explanation, see:

https://en.wikipedia.org/wiki/Past_hypothesis

You can happily run physics backwards and forwards, and there's no difference. But assuming that entropy was very low in the distant past is very useful and lets us talk about fascinating things, like what happened last tuesday (or 12 billion years ago)

If you just know the current state of the a system, there isn't really any difference between running time backwards and forwards. Of course, if you know exactly the state of every particle, field, etc, and the past hypothesis is true, running time one way will lead to lowering entropy, and the other way will lead to raising entropy. But if you're a mere mortal and just know the macrostate, either way you run time, the entropy of the system will increase.

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

#26

Post by thom »

All of this should be familiar to the average programmer. The Creator (I call him Colin), rushed for time and bereft of more elegant ideas, has widely deployed lazy loading as a solution to the finite processing power of the universe. Almost all of physics (the speed of light, the expansion of space, quantum entanglement) is an answer to the question of how the universe (and indeed Colin himself) can avoid doing too much work.

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

#28

Post by hikingsimulator »

msuniverse2026 wrote: post #19

In Anthroposophy or Western occult science time runs in reverse in something we call the etheric body. The physical body on the other hand is something that experiences the world through organs that register only the present moment. It can't perceive what no longer physically exists or what has not yet manifested physically. The etheric is a time-body, containing the complete formative record of one's biography and i…

Given how "western occult science" is just magical thinking and pseudo babble, it hardly fits on HN. Additionally, "western occult science" typically glosses over its 1920-1940s roots and branches. Wondering why...

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

#30

Post by tacker2000 »

ChuckMcM wrote: post #14

This was perhaps my favorite part of Physics 390 ("modern physics") which was about quantum dynamics and relativity. The speed of light is defined in terms of a velocity (~300,000,000 m/s) but if you were traveling at the speed of light time stops (which keeps the rule that its constant in all frames of reference). That and time passes more quickly at higher altitudes and these days we can actually measure that. Wild…

Also see the twin paradox, which is related to this and equally fascinating.

If one twin stays on earth and the other makes an intergalactic trip (with the speed of light), upon return, the one on earth will have aged much more than the one on the trip.

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