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Stopping time

Posted: Wed Feb 21, 2018 3:55 pm
by Atla
Here is a hilarious way to speed up, slow down or theoretically stop time evolution.

So take a quantum system, for example an unstable particle, that will soon decay. Keep observing this particle as frequently as possible.

(It is not possible to observe it infinitely frequently, so time evolution can't be 100% stopped, this can only be approached. Neither is it really known what "observe" means here, but a measuring device or an adult human seems to do the trick. Whether or not this is completely true is not the point here.)

So we keep observing the particle that will soon decay. And it never decays, because we have "frozen it in time" (arrested it's time evolution). Or at least we slowed it down to an almost complete halt.

Depending on the frequency of observation, we can also speed it up in time, so the decay will likely happen faster than it should.

-----------------------

Time is already a difficult thing to think about in several ways, so I thought why not make it even more confusing. :)

So for example one could wonder, when we suddenly stare at an analog watch, does the seconds dial sometimes really stop for a moment, or is our mind simply playing a trick on us?

Re: Stopping time

Posted: Thu Feb 22, 2018 7:07 am
by Noax
Atla wrote: Wed Feb 21, 2018 3:55 pm Here is a hilarious way to speed up, slow down or theoretically stop time evolution.

So take a quantum system, for example an unstable particle, that will soon decay. Keep observing this particle as frequently as possible.


So we keep observing the particle that will soon decay. And it never decays, because we have "frozen it in time" (arrested it's time evolution). Or at least we slowed it down to an almost complete halt.
Not sure what you mean by the term 'time evolution', but you seem to imply that the decay of a particle can be affected by keeping it under observation, sort of a watched-pot never boiling sort of thing. Take something simple like a helium-6 atom, which will likely decay in just under a second. Are you proposing that this decay will be delayed by frequent observation of it? What makes you think this is so?

I suppose it can be hastened by observing it in a sufficiently high-energy manner, similar to one's ability to hasten the decay of my life via 'observation' via interaction with a sufficiently high-energy bullet, but doing so would not seem to have any effect on what you deem to be 'time evolution'.

[/quote]Whether or not this is completely true is not the point here.[/quote]It is completely untrue, but if that's not the point, what is?

Re: Stopping time

Posted: Thu Feb 22, 2018 7:26 am
by Atla
Noax wrote: Thu Feb 22, 2018 7:07 am Not sure what you mean by the term 'time evolution', but you seem to imply that the decay of a particle can be affected by keeping it under observation, sort of a watched-pot never boiling sort of thing. Take something simple like a helium-6 atom, which will likely decay in just under a second. Are you proposing that this decay will be delayed by frequent observation of it? What makes you think this is so?

I suppose it can be hastened by observing it in a sufficiently high-energy manner, similar to one's ability to hasten the decay of my life via 'observation' via interaction with a sufficiently high-energy bullet, but doing so would not seem to have any effect on what you deem to be 'time evolution'.
Yes, a watched quantum pot never boils. If we have a helium-6 atom in quantum state and we observe it frequently, it should not decay. This is so because when we observe it, we keep reseting it's state. No high energies, or any energy transfer, is involved, just the observation.
It is completely untrue, but if that's not the point, what is?
It's not untrue, I just wanted to avoid the endless discussion of trying to correctly interpret QM for now.

Re: Stopping time

Posted: Thu Feb 22, 2018 4:41 pm
by Noax
Atla wrote: Thu Feb 22, 2018 7:26 am Yes, a watched quantum pot never boils. If we have a helium-6 atom in quantum state and we observe it frequently, it should not decay. This is so because when we observe it, we keep reseting it's state. No high energies, or any energy transfer, is involved, just the observation.
Nonsense. The above is an empirical claim, so independent of interpretation. No data exists to support this notion.
It is completely untrue, but if that's not the point, what is?
It's not untrue, I just wanted to avoid the endless discussion of trying to correctly interpret QM for now.[/quote]My comments are not based on any interpretation. If one claims to know the correct interpretation, they'd be mistaken. If there was a way to know it, they would not be interpretations.

Re: Stopping time

Posted: Thu Feb 22, 2018 5:46 pm
by Atla
Noax wrote: Thu Feb 22, 2018 4:41 pm Nonsense. The above is an empirical claim, so independent of interpretation. No data exists to support this notion.
Hmm so you don't think that this is how the world works?

Re: Stopping time

Posted: Fri Feb 23, 2018 8:13 am
by Atla
So anyway. It's called the quantum zeno and anti-zeno effects. This is how the world works and it's experimentally verified.

Re: Stopping time

Posted: Fri Feb 23, 2018 6:58 pm
by Noax
Atla wrote: Fri Feb 23, 2018 8:13 amSo anyway. It's called the quantum zeno and anti-zeno effects. This is how the world works and it's experimentally verified.
Cool. Learned something. I was speaking of radioactive decay. This effect seems more to be seen with decay of an excited state to a more base state, like electricity exciting the filament atoms of a light bulb, which then decay over time, emitting photons. Apparently if you measure the filament faster than that decay rate, the light shines less.
I retract my uniformed assessment of 'nonsense'.

My one comment is that 'staring at' is not observation. They mean 'doing something to it', not letting it do something to you. So the methods I see is bathing the sample in radiation of just the right frequency to reset those quantum states. So the act of staring is just noticing photons that have already measured the observed thing at some time in the past.

My analog watch second-hand really does stand still between ticks, which are I think 5 per second. Many quartz watches are motionless most of the time and tick once per second. Mine is not quartz, and unfortunately not as accurate either.

Re: Stopping time

Posted: Fri Feb 23, 2018 7:36 pm
by Atla
Noax wrote: Fri Feb 23, 2018 6:58 pm My one comment is that 'staring at' is not observation. They mean 'doing something to it', not letting it do something to you. So the methods I see is bathing the sample in radiation of just the right frequency to reset those quantum states. So the act of staring is just noticing photons that have already measured the observed thing at some time in the past.
The way I understand it right now and I may be wrong, but then again no one knows it: well if only it was that simple. Generally speaking (not just quantum zeno) "doing something to it" or "letting it do something to you" has nothing to do with an observation. However most observations do involve "doing something to it" hence the illusion. "Doing something to it" can also cause coherence with the environment but that's not quite the same thing.

The latest idea is this: if the state of such a quantum system is knowable in any way to the observer, then there will be a collapse. It doesn't matter where that data is, you can choose to never look at the data, instead put it on a rocket and send it to the Andromeda galaxy. And there will still be a collapse. Roughly speaking, what matters is the availability of the data to the observer, not interaction.

Re: Stopping time

Posted: Fri Feb 23, 2018 8:06 pm
by Atla
Now an "availability of data" can also be a tricky thing. For example you can set up a measuring device that attempts to record the data, the RW head is moving but it has no tape to record the data on.
But you will probably still get a collapse. Because the movement of the RW head itself, has leaked the data into the environment.

And when data is recorded but then erased and then you look at the result, you will not get a collapse. Because data is not available to you.

Re: Stopping time

Posted: Sun Feb 25, 2018 7:20 am
by gaffo
Atla wrote: Wed Feb 21, 2018 3:55 pm Here is a hilarious way to speed up, slow down or theoretically stop time evolution.

So take a quantum system, for example an unstable particle, that will soon decay. Keep observing this particle as frequently as possible.

(It is not possible to observe it infinitely frequently, so time evolution can't be 100% stopped, this can only be approached. Neither is it really known what "observe" means here, but a measuring device or an adult human seems to do the trick. Whether or not this is completely true is not the point here.)

So we keep observing the particle that will soon decay. And it never decays, because we have "frozen it in time" (arrested it's time evolution). Or at least we slowed it down to an almost complete halt.

Depending on the frequency of observation, we can also speed it up in time, so the decay will likely happen faster than it should.

-----------------------

Time is already a difficult thing to think about in several ways, so I thought why not make it even more confusing. :)

So for example one could wonder, when we suddenly stare at an analog watch, does the seconds dial sometimes really stop for a moment, or is our mind simply playing a trick on us?
time - the forward progression is part if it -is the 4th dimension in our space.

in other "spaces" - inside BH who knows.

Re: Stopping time

Posted: Sun Feb 25, 2018 7:20 am
by gaffo
Atla wrote: Wed Feb 21, 2018 3:55 pm Here is a hilarious way to speed up, slow down or theoretically stop time evolution.

So take a quantum system, for example an unstable particle, that will soon decay. Keep observing this particle as frequently as possible.

(It is not possible to observe it infinitely frequently, so time evolution can't be 100% stopped, this can only be approached. Neither is it really known what "observe" means here, but a measuring device or an adult human seems to do the trick. Whether or not this is completely true is not the point here.)

So we keep observing the particle that will soon decay. And it never decays, because we have "frozen it in time" (arrested it's time evolution). Or at least we slowed it down to an almost complete halt.

Depending on the frequency of observation, we can also speed it up in time, so the decay will likely happen faster than it should.

-----------------------

Time is already a difficult thing to think about in several ways, so I thought why not make it even more confusing. :)

So for example one could wonder, when we suddenly stare at an analog watch, does the seconds dial sometimes really stop for a moment, or is our mind simply playing a trick on us?
time - the forward progression is part if it -is the 4th dimension in our space.

in other "spaces" - inside BH who knows.

Re: Stopping time

Posted: Sun Feb 25, 2018 7:20 am
by gaffo
Atla wrote: Wed Feb 21, 2018 3:55 pm Here is a hilarious way to speed up, slow down or theoretically stop time evolution.

So take a quantum system, for example an unstable particle, that will soon decay. Keep observing this particle as frequently as possible.

(It is not possible to observe it infinitely frequently, so time evolution can't be 100% stopped, this can only be approached. Neither is it really known what "observe" means here, but a measuring device or an adult human seems to do the trick. Whether or not this is completely true is not the point here.)

So we keep observing the particle that will soon decay. And it never decays, because we have "frozen it in time" (arrested it's time evolution). Or at least we slowed it down to an almost complete halt.

Depending on the frequency of observation, we can also speed it up in time, so the decay will likely happen faster than it should.

-----------------------

Time is already a difficult thing to think about in several ways, so I thought why not make it even more confusing. :)

So for example one could wonder, when we suddenly stare at an analog watch, does the seconds dial sometimes really stop for a moment, or is our mind simply playing a trick on us?
time - the forward progression is part if it -is the 4th dimension in our space.

in other "spaces" - inside BH who knows.

Re: Stopping time

Posted: Sun Feb 25, 2018 7:21 am
by gaffo
Atla wrote: Wed Feb 21, 2018 3:55 pm Here is a hilarious way to speed up, slow down or theoretically stop time evolution.

So take a quantum system, for example an unstable particle, that will soon decay. Keep observing this particle as frequently as possible.

(It is not possible to observe it infinitely frequently, so time evolution can't be 100% stopped, this can only be approached. Neither is it really known what "observe" means here, but a measuring device or an adult human seems to do the trick. Whether or not this is completely true is not the point here.)

So we keep observing the particle that will soon decay. And it never decays, because we have "frozen it in time" (arrested it's time evolution). Or at least we slowed it down to an almost complete halt.

Depending on the frequency of observation, we can also speed it up in time, so the decay will likely happen faster than it should.

-----------------------

Time is already a difficult thing to think about in several ways, so I thought why not make it even more confusing. :)

So for example one could wonder, when we suddenly stare at an analog watch, does the seconds dial sometimes really stop for a moment, or is our mind simply playing a trick on us?
time - the forward progression is part if it -is the 4th dimension in our space.

in other "spaces" - inside BH who knows.

Re: Stopping time

Posted: Sun Feb 25, 2018 1:49 pm
by Atla
Yeah these everyday things called space, time, causality, actions.. they don't really seem to exist in the quantum world at all, they are more like an apparent special case of the quantum world. So even gravity might not exist fundamentally, which might be why it can't be unified with the other forces.

In the quantum world there only seem to be correlations that ignore time and distances. Even apparent retrocausality, or breaking the speed of light, is perfectly normal in QM.

Re: Stopping time

Posted: Sun Feb 25, 2018 9:39 pm
by uwot
Atla wrote: Sun Feb 25, 2018 1:49 pmIn the quantum world there only seem to be correlations that ignore time and distances. Even apparent retrocausality, or breaking the speed of light, is perfectly normal in QM.
Really? Can you cite your source for this?