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Problem of Time
- DrFell 7y agoThe problem of time comes from the notion that we are matter existing through time, instead of realizing sentience is made of events.
- ISL 7y agoEven if it is an ordered series of events, why does it appear to have a direction to the ordering?
- stagas 7y agoThe direction is purely philosophical. Things are changing from one state to the other. Even if it was backwards, you'd still convince yourself that it is the forward way. Things simply change.
- DrFell 7y agoCausality, I guess would be my answer there.
- AnimalMuppet 7y agoBut in your view of time, what is causality? Can it even exist?
- stagas 7y agoAre there distinct events in the real world or we simply draw the lines arbitrarily simply for the sake of practicality? The whole existence could be the light of a match, experienced in an immensely detailed spacetime scale.
- teilo 7y agoPrecise clocks don't care about your sentience or lack thereof. They still measure the gravity and speed-induced time dilation that is entirely missing in quantum mechanics. Relativity is a physical phenomenon that does not require sentience to operate, and time is part of that physical phenomenon.
- DrFell 7y agoClocks appear to tick because we are locked in a series of moments. The clock exists at all times it has or will show.
- jayd16 7y agoBut how does this solve for relativistic time dilation?
- DrFell 7y agoMy conjecture that consciousness is made of events is an attempt to explain why we see ‘the problem of time’. There are more widely accepted concepts around the subject, like the idea that all moments in time exists equally, not just now. Now is a slice through the cosmos that really exists. I have had thoughts about how relativistic effects work with that, but I honestly think I went far enough. I leave that to others to think about or scoff at.
- blfr 7y agoRelativity is a physical phenomenon that does not require sentience to operate We do not and cannot know that because all observations me make involve sentience. In fact, we can't even know if anything exists without sentience.
- JoeAltmaier 7y agoNope. The universe 'notices', by reacting in exactly the way you'd expect if relativity was happening. That last bit - "...we can't even know.." is sophistry.
- blfr 7y agoThere is nothing sophistic about this argument. It's pretty obvious. This is why some people argue that we might be living in a simulation. Because we don't have direct (not mediated by our senses) access to the underlying reality.
- Razengan 7y agoMaybe I’m not smart enough to find time as confusing as these things try to point out: Time is the sequence of states every time the rules are applied, or am I missing something?
- fsh 7y agoThis would imply that time progresses in steps. There is no hint that this is the case.
- mjfl 7y agoAccording to general relativity, the time order of events is relative depending on your position and velocity. This also seems to break causality in textbook quantum mechanics since local changes can lead to global adjustments (collapse, for one) of the wavefunction.
- fallingfrog 7y agoThat’s an intuitive understanding, but it doesn’t account for quantum effects like superposition, and it doesn’t account for relativistic effects either. Basically the answer has to be something like: in the multiverse of possible arrangements of particles, some of them are in your past, some of them are in your future, and some are in neither, but which depends on the observer, who is inside the universe they are trying to describe, and that creates the illusion of the flow of time. I don’t totally get it either.
- badrabbit 7y agoLet me ask you this: if there was no change, no interaction even between qanta, would there be time?
- luxuryballs 7y agoalso: if you had absolutely no memory or way of recording and comprehending the previous arrangements of space/matter
- colinhb 7y agoThink of a donut. Think of a vertical plane through the donut. The plane has two disconnected circles on it. Imagine trying to move the two circles apart. They resist your effort because they are attached together through their three-dimensional structure. In one view of time (“eternalism”, roughly speaking) saying “there is no change” or “no interaction” between any particles in the universe would mean that in the fixed structure of the universe of which time is a dimension, everything is constant in the direction of that dimension. So the two statements become roughly equivalent.
- saagarjha 7y agoThis is a pretty awful Wikipedia article. Unless it’s a plea for an actual expert in the field to go in and fix it, I’m not seeing how this is a good submission :(
- stagas 7y agoIt is an interesting discussion topic, people are confined to their houses for many days now and naturally experience existential issues. And, because noone sees the world the same way, HN relies on a sophisticated algorithm that tries to minimize bias on what is a good and what is a bad submission. A more constructive approach would be to point out why you think it is an awful article and share some knowledge on the topic.
- saagarjha 7y agoI have nothing against the topic, I think the Wikipedia article is incredibly poor. It does little to explain the topic and presents a one-sided viewpoint authoritatively when it seems anything but. It’s clearly lacking an encyclopedic tone. There’s a couple of warnings for its poor quality both in the article itself and on the talk page.
- mjfisher 7y agoJust to add to what saagarjha said; there's large parts of the article that just don't seem to make sense on their own. I only have a Master's degree in Physics, and haven't specialized in general relativity - nevertheless I usually have enough background to at least follow along with Wikipedia. In particular, the "Overturning of absolute time in general relativity" section is very hard to follow, and I suspect would only make passing sense to a reader already very familiar with the subject matter. It has a very stream-of-consciousness feel to it, it doesn't introduce concepts as it moves along, and it makes unexplained logical leaps from one idea to another. I'm glad someone took the time to start the article and it sounds like an interesting subject; but it could certainly see improvement from someone with the right knowledge.
- acqq 7y ago
- greenstork 7y agoIsn't time just a history of movement? For example, if you stopped the movement of everything in the universe (all the way down to subatomic particles) for a "moment" and then turned movement back on again, how long would that moment have lasted for? 1 second or 100 years? There's no way to define how long that moment lasted, since nothing was moving during that moment. So it seems to me that time cannot exist without movement which makes me think that time is a byproduct of motion (a history of motion).
- Yajirobe 7y ago> how long would that moment have lasted for? 0 seconds.
- sgillen 7y agoMaybe, it’s an open question whether or not what you are calling time is a useful way to look at the problem the article is talking about. The article wants to know if time is a universal constant (as in quantum mechanics) or if it’s malleable and relative (as in general relativity). It’s not clear to me if viewing time as a history is useful here.
- Der_Einzige 7y agoIs there any evidence of a fundemental quantized unit of time existing? Can I fundementally treat time as continuous or discrete? Plank time isn't good enough because it's possible that we see a phenomenon that happens over a shorter time period and that we need better instruments. This question very important to me because I don't see a possibility that we can situate identity as existing metaphysically without quantized time. It also seems to imply to me that determinism is wrong. But please correct me on this you big-brains I don't study quantum physics or general relativity
- mellosouls 7y agoSo far many of the comments seem to have misread the article, which doesn't seek to address the mystery of what time is directly, but rather it describes a supposed mismatch between quantum and classical (via general relativity) interpretations of it's essence.
- skat20phys 7y agoI don't mean to sound snarky, but aren't those two problems related?
- mellosouls 7y agoSure, and the article goes on to discuss time itself as a necessary consideration, but it's not the main focus - the title is somewhat misleading.
- deleted 7y ago[deleted]
- peter_d_sherman 7y agoExcerpt: The quantum concept of time was invented by physicist Bryce DeWitt in the 1960s:[5] "Different times are special cases of different universes."
- KingFelix 7y agoThe Order of Time - Carlo Rovalli, great read if anyone is looking for a book on time. Also, Your brain is a time machine - Dean Buonomano
- niketdesai 7y agoThanks for the recommendation. I'm going to check out Rovalli's book.
- enricozb 7y ago> no known physical laws seem to require a single direction. What would a physical law that required a single direction look like?
- hoorayimhelping 7y agoI believe it looks like this: https://en.wikipedia.org/wiki/Speed_of_light https://en.wikipedia.org/wiki/Speed_of_light That physical limitation on how fast a mass can move is what keeps causality in check and things like the grandfather paradox from being possible. Edit: now that I think more on it, this is probably a better law that ensures causality: https://en.wikipedia.org/wiki/Entropy#Second_law_of_thermodynamics https://en.wikipedia.org/wiki/Entropy#Second_law_of_thermody...
- ethn 7y agoAs another HN member mentioned, this is a pretty awful article. What is the alleged conflict supposed to be? It's my understanding that quantum mechanics necessarily describes systems in a single inertial reference frame, so for that system, time is absolute w.r.t to both general relativity and QM.
- lonelappde 7y agoAs the article explains, time in Relativity is not Absolute, it's.... Relative.
- ethn 7y agoIn General Relativity time is absolute throughout the same inertial reference frame...
- Vysero 7y agoWhy do I get the feeling that when they do finally figure out what time is it's somehow going to be related to imaginary numbers: The complexity of things - the things within things - just seems to be endless. I mean nothing is easy, nothing is simple. ~Alice Munro