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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

#81

Post by card_zero »

ben_w wrote: post #79
card_zero wrote: post #56

Earlier quoted context omitted.

If we say that seconds "pass", at what rate do they pass? Could they pass at some rate other than one second per second? That would entail outer seconds (second seconds, if you like). Which also have their own rate at which they pass, so now we need a third-level "flow of time", and so on. So to say seconds "pass" is describing something else. They aren't moving.

> If we say that seconds "pass", at what rate do they pass? One second per second for yourself, but other observers generally disagree. Or one could use it as an inverse of the things measured against time, so meters/second of speed can be turned into seconds flowing at a rate of length. Does "miles per gallon" lead to similar questions about gallons passing? > Could they pass at some rate other than one second per s…

You're talking about something else. Or rather, my line of argument ran into a distraction hazard, namely relativity. I wasn't trying to talk about relativity, but I should have seen that coming. And now everybody's very keen to explain relativity to me, dammit.

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

#82

Post by actionfromafar »

smokel wrote: post #41
ndsipa_pomu wrote: post #36

Earlier quoted context omitted.

I bet Colin gets annoyed every time we point a telescope at far away objects as he has to rush around behind the scenes and paint in all the details.

Wait until you hear how he performs garbage collection.

Arena allocators?

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

#84

Post by ben_w »

card_zero wrote: post #81
ben_w wrote: post #79

Earlier quoted context omitted.

> If we say that seconds "pass", at what rate do they pass? One second per second for yourself, but other observers generally disagree. Or one could use it as an inverse of the things measured against time, so meters/second of speed can be turned into seconds flowing at a rate of length. Does "miles per gallon" lead to similar questions about gallons passing? > Could they pass at some rate other than one second per s…

You're talking about something else. Or rather, my line of argument ran into a distraction hazard, namely relativity. I wasn't trying to talk about relativity, but I should have seen that coming. And now everybody's very keen to explain relativity to me, dammit.

I did give a response to the non-relativity interpretation too.

Sure, it wasn't clear which way you were going with that question, but I recognised that it could have been either.

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

#85

Post by card_zero »

ben_w wrote: post #84
card_zero wrote: post #81

Earlier quoted context omitted.

You're talking about something else. Or rather, my line of argument ran into a distraction hazard, namely relativity. I wasn't trying to talk about relativity, but I should have seen that coming. And now everybody's very keen to explain relativity to me, dammit.

I did give a response to the non-relativity interpretation too. Sure, it wasn't clear which way you were going with that question, but I recognised that it could have been either.

Time having a static existence, and all moments of time being equally real, ought to boggle the mind. Then again, it's not compulsory to be boggled, goodness knows it's exhausting and doesn't accomplish much.

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

#86

Post by ben_w »

card_zero wrote: post #85
ben_w wrote: post #84

Earlier quoted context omitted.

I did give a response to the non-relativity interpretation too. Sure, it wasn't clear which way you were going with that question, but I recognised that it could have been either.

Time having a static existence, and all moments of time being equally real, ought to boggle the mind. Then again, it's not compulsory to be boggled, goodness knows it's exhausting and doesn't accomplish much.

Hm.

I only find that boggling in the context we both agree you're not using: relativity (block universe in particular).

In so far as we ignore all of relativity because it's so counter-intuitive and strange, "all moments of time being equally real" seems as trivial and straightforward as "all places in cartesian 3-dimensional space being equally real".

But yes, boggling is never compulsory.

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

#87

Post by skissane »

RobotToaster wrote: post #57
gyomu wrote: post #42

Earlier quoted context omitted.

> A photon is, from its point of reference, at the point of creation and at the point of destination at the same "time" > every photon exists, from its point of view, for only infinitely small amount of time Why is that amount “infinitely small” and not 0 since photons travel exactly at the speed of light?

Existing for zero time would imply it never existed.

> Existing for zero time would imply it never existed.

In the mathematics of infinity, something can have exactly zero probability yet still happen, and exactly one probability yet nonetheless fail to happen (hence the standard term “almost surely”).

If something can have literally zero probability of existing yet still exist, why can’t it exist for literally zero time yet still exist?

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

#88

Post by gilbetron »

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…

My favorite explanation: https://www.youtube.com/watch?v=Vitf8YaVXhc

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

#89

Post by skissane »

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.

> 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.

Our experience of time passing is heavily influenced by the temporal granuality of our subjective experience-at the upper end, “now” lasts 2-3 seconds; at the lower end, our temporal discrimination goes down to tens of milliseconds for visual and tactile stimuli, and reaches down to microseconds for certain types of auditory stimuli. But, one supposes other species with different neurology would have these durations be shorter or longer, which would make time pass more slowly or faster for them, in subjective terms.

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

#90

Post by user3939382 »

Antibabelic wrote: post #64
user3939382 wrote: post #47

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

Would you like to share any details?

I would love to. Unfortunately when you’re talking about physics the community doesn’t welcome casual conversations, that’s been my experience. If you start with anything less than a formal proof all the hackstchuallys come out. So I will start with the proof, soon. Working with some academics on peer review now.
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