Want to Know What Time Is?
post by Alexander Weinmann (alexander-weinmann) · 2019-03-07T19:49:29.465Z · LW · GW · 8 commentsContents
What is time? We consider time to be just the sum of all the information gathered during experiments. Now you know what time is! None 8 comments
I do not consider myself to be smart enough to answer a question that remains unanswered since thousands of years:
What is time?
Nevertheless I will answer that question now. I am asking every person smarter than me to explain to me, why my answer must be wrong. More so: There may even be some very basic mathematics below. I am very keen to find out why this mathematics is either wrong or irrelevant – or simply stupid. It sure is!
I define time as the amount of information available for a given phenomenon.
If there is a lot of information, then the phenomenon is considered to exist for a very long time. If only little information is available, the phenomenon is considered to exist for a very short time only.
For example, if a guy called Join Doe is traveling from Berlin to Moscow, there might be at least two bits of information about this:
- John Doe is in Berlin
- John Doe is in Moscow
If there is no other information available, then the phenomenon is very short lived, meaning John was traveling at maximum speed. That could be the speed of light.
But there might be more information available: John might take a stop in Minsk, because he loves a most beautiful Belarus girl at that place. It just means, that his travel speed is much slower. Far from the speed of light in this very case! So there is more time between his departure in Berlin and his arrival. It might even happen, because he is so very much in love with this girl, that he will never arrive in Moscow. In that case, the amount of time between departure and arrival is infinite.
Time Tcan thus be seen as function of the discrete amount N of available information: T(N) We know that for any N_1,N_2 with N_2 > N_1there will always be T(N_2) > T(N_1).
(But apart from that I do not really know a lot about the function T(N).)
Please note that by this definition there is no direction associated with time! So, time does not really tell us if Johnny starts his journey in Berlin or in Moscow. We can only be sure that he was in Minsk, and that he was having a great time there, wishing to stay for ever with the girl. (Maybe she also really cares a lot about him!)
Things are getting more interesting, if we – for example – consider a black hole. As we know by the theory of relativity, time “is slowing down” a bit, the nearer you get to a black hole. Now, let us look at John Doe again: Imagine this guy is getting really close to a black hole. (There is no reason whatsoever to compare his relationship with his girl to a black hole or find any other similarities or even more vulgar comparisons related to her.) Just imagine that John is attracted to the black hole just as he is attracted to his girl friend. The nearer he is getting to the black hole, the lesser are his chances to escape. A black hole squeezes a lot of matter into a tiny space, increasing its gravitational field and decreasing time in comparison to other people lucky enough to stay farer away from the black hole. (Still, please no comparisons to the girl friend!)
If John finally reaches the center of the black hole, there will be no more doubt about his very location. No longer will he be in Berlin! He will not be in Moscow, nor in Minsk. No matter how often we would request his position, we will always be sure that we could find him in the center of the black hole. Thus the amount of available information about his position has reached infinity, the uncertainty about his whereabouts has reached 0, and thus time will now longer flow. Time will stand still, and there will be no time at all at the center of a black hole.
As you can see, we can explain the behaviors of time in a very strong gravitational field, even without the nasty complexity of general relativity.
Let me give you another example: The double-slit experiment, seen from the viewpoint of quantum theory. As we know, getting information about a quantum system always implies doing an experiment, and the results will vary depending on their probabilities. The more experiments we do, the more information we will get about the location of a particle. Some very smart people would most likely say, that the Schrödinger equation collapses with each experiment, meaning that a probability wave will turn into some (trivial) information about something. Whatever that means, it is obvious to us that information pops up in exchange of a certain amount of uncertainty that we are loosing on the way.
We consider time to be just the sum of all the information gathered during experiments.
In particle physics, the path of a particle is somewhat indeterminate. No matter how many experiments we do, we will only end up with an approximate path of the particle. OK. But if we repeat the experiment under the exact same conditions, we might end up with a completely different path, only depending on some probabilistic rules determined by the maths of quantum physics.
But with our understanding of time that does not really bother us any longer. There is no order in time. Time does not flow from 0 to infinity, always in the same direction. It is just the sum of all the information that we can gather. And that does not need to be the same all the time!
Now you know what time is!
8 comments
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comment by ryan_b · 2019-03-08T16:05:43.197Z · LW(p) · GW(p)
Welcome to LessWrong!
The central issue I see with this argument is that it seems to assume time in the setup to the examples, or implicitly in the equation. For example:
For example, if a guy called Join Doe is traveling from Berlin to Moscow, there might be at least two bits of information about this:
John Doe is in Berlin
John Doe is in Moscow
How do we distinguish between the Berlin to Moscow case, and the Moscow to Berlin case? You mention this point later:
time does not really tell us if Johnny starts his journey in Berlin or in Moscow.
So I can accept the argument that Berlin,Moscow and Moscow,Berlin are the same amount of time - it stands to reason that doing the same thing in reverse order should take the same amount of time, which the information rule seems to capture. But this doesn't seem to square with the Minsk example:
it might even happen, because he is so very much in love with this girl, that he will never arrive in Moscow. In that case, the amount of time between departure and arrival is infinite.
Based on the previous example I would expect Berlin,Minsk,Moscow to be the same as Moscow,Minsk,Berlin, and this seems to hold up - but it doesn't seem consistent that Berlin,Minsk,Moscow is more time than just Berlin,Moscow and yet Berlin,Minsk is infinite.
It also looks to me like we have a problem with trying to integrate new kinds of information. For example, under this rule Berlin,Minsk,Moscow and Berlin,Paris,Moscow are the same amount of time - but when we look at the map we see Paris is farther away from Moscow than Berlin is. How do we account for this, under the rule?
comment by etsim · 2019-03-08T14:34:15.264Z · LW(p) · GW(p)
As a few threshold considerations:
How do you determine what "information" is relevant? And at what level of detail? I could zoom in on any number of areas of inquiry about John's original "instantaneous" journey and come up with additional information until the cows come home. In doing so, it seems that the "time" conclusion would change based in what information I deem relevant.
As another big issue, I would ask what qualifies information as being "available". In other words, available to who?
It seems to me that your proposal gives ad hoc answers to these questions which fit your desired outcome.
More generally speaking, I think you need to fold a whole lot more subjectivity into a conception of time. In my view, time itself is a quale.
comment by countingtoten · 2019-03-09T09:40:58.931Z · LW(p) · GW(p)
The first potential problem I see is that "information available" should be relative to an information-storage device like a human brain, whereas time in (my limited understanding of) physics is relative to a rock or other physical frame of reference. Those seem different.
If we try to remove that problem then we get a new one (which might exist anyway in a less acute form). When we take as our "given phenomenon" something large in spatial area, like 'the Earth at exactly 4:40 am EST in this frame of reference,' we find vastly more available information than we could have - even in principle, I would think - for many phenomena we would consider to take more time. So this definition doesn't seem to match the word.
Replies from: TAG↑ comment by TAG · 2019-03-09T12:04:17.614Z · LW(p) · GW(p)
It doesn't match a certain way of defining "information". But some people are quite happy with notions of information that aren't tied to a subject. You can reconcile the two by saying that objective information is potential subjective information.
comment by Slider · 2019-03-08T15:00:55.309Z · LW(p) · GW(p)
If I study history with this view I would be moving events in time. There seems to be a lot of implicit assumtions that could go multiple ways needed to make it compatible with ordinary time phenomena.
There seems to be similarity with Zeno's arrows in that if each state is considered separately no movement occurs. Is this just a restatement of that view?
comment by Alexander Weinmann (alexander-weinmann) · 2019-03-08T18:08:09.989Z · LW(p) · GW(p)
Thanks very much for wonderful replies! There are not many places in the net where such articles can be published and are read! I am confident that my thoughts can only get less wrong, if they received some feedback. So you guys make me happy!
@ryan_b Do not look at maps or watches to understand time! It did not help in two milleniums. Since Einstein we live in space-time, and it does not make sense to talk about time without context. Imagine there were considerably more mass concentrated in Paris, then in Berlin. Very, very, very fat people for example! That would bend space-time, clocks would be slower in Paris, and Paris could indeed be nearer to Moscow than Berlin, considering all possible measurements.
@Slider Yes! It is a “playful” concept, full of details that needed to be ironed out. For now, I find it very interesting to ignore the fact that we experience time as directed. I tried to start with a new concept, completely independent of everday’s experience. How we experience time might be misleading. The whole phenomenon might be an illusion.
@etsim Yes, indeed! Subjectivity! Since Einstein, time depends on the relative speed you have compared to somebody else. – What information is relevant? When I wrote the article, I dared concentrating on the information about speed and position of “something”, say a particle. But that is plain physics, and I am not the right guy for such stuff. But I know about the uncertainty principle: Speed and location cannot be determined with the same accuracy at the same time. There is always uncertainty involved. Missing information? A missing understanding? I find these things very, very interesting and fascinating.
comment by bubblesort · 2019-03-08T18:56:50.694Z · LW(p) · GW(p)
What an inspiring thought. I love ideas like yours, mainly because I was taught philosophy at UCL in London UK. At the time Arnold Zuboff was a lecturer there and his ideas were as interesting as yours. I was there some time around 1992 or 3, I last spoke to him around 2004 maybe 2006. UCL may be able to put you in touch with him, as they did that for me. He is very good at discussing ideas such as yours in emails and on sites such as this. Let me assure you, Zuboff is a genius. Here is a paper he wrote regarding time and self identity https://philpapers.org/rec/ZUBMUA
I am fairly certain, and I hope I'm not wrong or embarrassing myself or him in some way but seriously, get his advice