9 ms·
I find it really fascinating to think that when 60 minutes pass on star S62, on Earth 100 minutes would have passed in the same duration. This is Sci-Fi territo
by brainless 6y ago
I find it really fascinating to think that when 60 minutes pass on star S62, on Earth 100 minutes would have passed in the same duration. This is Sci-Fi territory in my mind. I am having all sorts of difficulty imagining some implications of this.
Does this roughly mean, things are "sped up" in S62 from our point of view, if we could observe some activity on that star?
- wtmt 6y ago> This is Sci-Fi territory in my mind. Simpler Sci without the Fi, but still incredible to lay people, is that earth’s gravity and the movement of the satellites cause time dilation that’s accounted for in GPS satellite clocks and the receiver clocks. It’s amazing how much the Special Relativity and General Relativity influence our daily lives. See: The Wikipedia entry on GPS.
- spyder 6y agoYes: Time go faster at the top of a building compared to the bottom. https://wtamu.edu/~cbaird/sq/2013/06/24/does-time-go-faster-at-the-top-of-a-building-compared-to-the-bottom/ https://wtamu.edu/~cbaird/sq/2013/06/24/does-time-go-faster-...
- saagarjha 6y agoWell, it’s that and also their speed, the effects of which are predicted by general and special relativity respectively.
- saagarjha 6y ago> It’s amazing how much the Special Relativity and General Relativity influence our daily lives. I mean aside from the obvious one of it being an underlying theory for how the universe works and without it a lot of stuff would break it is really not that huge a part of most people’s lives. Sure, the GPS example is a fun one to bring up, but other than that there’s just a few things that we interact with that actually have a noticeable effect due to relativity, like some of the very characteristic properties of heavier metals or the design of particle accelerators, which many people used to have in their house until recently. And I guess you could go out and look at Einstein’s cross. But other than that it really doesn’t affect us that much.
- chrisweekly 6y agoHa! Apparently other mods didn't, but I appreciate your sense of humor. :)
- wruza 6y agoIt barely mentions the effect. Better see https://en.m.wikipedia.org/wiki/Error_analysis_for_the_Global_Positioning_System#Relativity https://en.m.wikipedia.org/wiki/Error_analysis_for_the_Globa... tl;dr we perceive gps satellites clock ticks faster due to lower gravity (+46us/day), but slower due to motion (-7us/day).
- brainless 6y agoYou are absolutely right. I guess I was just fascinated because of the stated difference, which some have pointed out is off by a factor of 10! Yikes, so much for reporting.
- j15e 6y agoI think its the opposite: things are slowed down on S62 so they can’t reach speed of light. That is how you could (in theory) go in the future because earth time would go faster if you were on S62. So if you could watch it, it would be slower?
- deleted 6y ago[deleted]
- floydnoel 6y agoI think they’ll appear slower to us. We’d be sped up to them. I’d love to be able to travel at half the speed of light, a few months and I’d be able to return far in the future.
- saagarjha 6y agoI’d hate to burst your bubble, but if you travelled at half the speed of light for what you think is a couple months, you’d come back in…a couple months. The dilation effect is only about 15% at that speed.
- yodsanklai 6y agoThis is the plot of the book "planet of the apes". The explorers think they are on a different planet, until they realize they are in a future earth (because they travel at near the speed of light in their spaceship). (hope I don't spoil anything, it's such a classic).
- dragontamer 6y agoYOU MANIAC! You spoiled the movie. Damn you. Damn you all to hell!
- vagab0nd 6y agoWhy do you do such a thing? You hope you don't spoil it but you just did the opposite.
- caf 6y agoTime there appears to pass slower to us (an observer here). But time here also appears to pass slower to them (an observer there)!
- mulmen 6y agoHow would FTL communication work? Let’s assume we can literally communicate over any distance instantly. Do we come across as a bit slow to anyone orbiting star S62? “Wow, these earthlings sure are hard to work with. They just can’t seem to keep up!” Do we have to remember that the people we communicate with have different experiences of time? Gender identity, sexual orientation, native language. Temporal perception? Honestly it doesn’t seem hard to overcome. But I do love the idea of shipping off a problem and having it done 20% faster. But wait, aren’t they 20% farther along in evolutionary terms too? So isn’t that like a multimillion year advantage?
- jedberg 6y ago> Do we have to remember that the people we communicate with have different experiences of time? This is already true on Earth. Different people process information at different speeds. Think about when you're talking to someone who is elderly. Do you slow down a bit so they have a chance to keep up?
- mulmen 6y agoYep, exactly. I was just chatting with someone in the park today who was much slower to process and respond than I am accustomed to. I was able to adapt to that and we had a nice conversation. It’s definitely a thing. Communication is messy. I do think this thought experiment is a bit different though. In the sense that everyone orbiting S62 is faster than us, by a considerable margin. There will still be individual variances of course but the baseline moves. It’s not just a way you adapt to an individual but to an entire group of people, based on properties of their location.
- prox 6y agoReminds me of that star trek voyager episode with the fast moving planet “Blink of an eye” Hours in our universe, is centuries on this planet that orbits at an incredible velocity.
- 6y ago
- pdonis 6y ago> I find it really fascinating to think that when 60 minutes pass on star S62, on Earth 100 minutes would have passed in the same duration. It doesn't; phys.org is way off in their math (if they even bothered to check the math).
- perbu 6y agoWay off. 60 minutes, 11 seconds on earth would be more like it.
- deleted 6y ago[deleted]
- tsbinz 6y agoIt looks like someone (in addition to forgetting to clearly state where the observer is) forgot a zero when putting it in the calculator, at 80% of the speed of light you get the time dilation factor they state.
- mikro2nd 6y agoFurthermore they betray a Northist bias that I find disappointing in an Astronomy article, when they say, "In the Fall of 2022..." For half the terraqueous globe it will, in fact, be Spring. And anyway, I think they really meant "Autumn", dammit! </curmudgeonly>
- neltnerb 6y agoYet from S62's perspective, we're the ones moving. It will be hard to imagine if you try to retain the concept of some universal clock. The important thing is that if you actually traveled from one to the other that during your accelerations time would warp around you so as to perfectly make both sides local clocks correct.
- samus 6y agoFrom S62's perspective, _everyone_ is moving. They would infer that S62 is the oddball, and not the galaxy around them.
- neltnerb 6y agoSure, and knowing that they're the oddball doesn't mean their physics is any different locally. This is the core concept of special relativity from which the rest is derived, neither of us is special in how our environment behaves. Whether you're on the spaceship traveling at 0.99c relative to earth or "at rest" (both are actually at rest but hopefully you know what I mean) everything feels the same as long as you are not accelerating.
- vagab0nd 6y agoBut S62 is special because it's constantly accelerating very fast (going in orbit). And that makes it special and not equivalent to us. Twin paradox is very similar. It's an apparent paradox but not real.
- thdrdt 6y agoLast week I watched the movie Interstellar and I still don't get why the main character could be younger than his daughter when he returns from space. And I also don't get your comment. Probably because I don't get relativity. If we send a clock into space it will just tick away seconds (a unit designed by people). When it will return back to earth years later in my mind it just ticked away the same amount of time as it would have on earth. What am I missing about relativity?
- chillee 6y agoIt will have ticked away less seconds. Time runs slower the faster you move. From the perspective of each individual person they wouldn't be able to tell the difference, but when they come back together they'll have passed different amounts of time.
- thdrdt 6y agoBut doesn't Einstein not talk about how you observe the clock when you move away from the clock? So the clock keeps ticking the same time but you can't observe it because you are traveling at the speed of light. So when you travel away from the earth at the speed of light you can't see the rotarion of the earth. But when you move back to the earth you are still just as old as the people who were the same age as you when you left?
- ben_w 6y agoI’m going to try a different thought experiment than the others. Imagine your clock is an LED, a light sensor, and a mirror. The “tick” of this clock is: the LED sends out a brief flash of light, which travels to the mirror, bounces off, and returns to the sensor. If this clock is stationary relative to you, the time of that tick is the distance between the three components divided by the speed of light (c = d / t). If it is moving relative to you, the light has to be at an angle, shining at where the mirror will be by the time the light gets there. This is a longer distance, and so it ticks more slowly from your perspective. Every atom in your body, or in a clock, is held together by forces that behave like the light in the example clock. Give two people clocks and have them move relative to each other, and both think the other is slow. This leads to the “twins paradox”, and while I can say the answer involves acceleration, I don’t fully intuit it and can’t help you with it.
- tsbinz 6y agoThere is a couple of things to keep in mind. First, like others mentioned, they are way off in the effect size, for this kind of time dilation you need 80% the speed of light, not 8%. Second, when looking at time dilation caused by velocity, it is always necessary to say who observes what since observers that move relative to each other won't agree on which clock runs at what speed. If the star moved at 80% of the speed of light, someone on that star would say "When a 100 minutes pass here, only 60 minutes pass on Earth" while an observer on Earth would say "When 100 minutes pass here, only 60 minutes pass on that star". So both observers would say that the other's clock is running slower than their own. This answers a part of your last question - time dilation always makes clocks appear to tick slower than your clock if they move relative to you. There are other effects that can make things appear "sped up", there's all kind of odd things happening when you go to high relativistic speeds ...
- eru 6y ago> Second, when looking at time dilation caused by velocity, it is always necessary to say who observes what since observers that move relative to each other won't agree on which clock runs at what speed. Interestlingly, the universe does have a preferred velocity (and thus a preferred inertial frame). It's the speed and direction that makes the cosmic background radiation not have a dipole. https://astronomy.swin.edu.au/cosmos/c/Cosmic+Microwave+Background+Dipole https://astronomy.swin.edu.au/cosmos/c/Cosmic+Microwave+Back...
- tinco 6y agoSo this velocity must be relative to some common point/area right? Like the center of the event that caused it? When they say "300,000 years after the big bang" how do they count that, is that seconds in some periodic movement inside matter or radiation?
- brnt 6y agoThere is no center to the source of the background radiation, as it is was created at a moment the universe was still a fairly homogeneous soup (apparently) with these photons being created (and absorbed) everywhere roughly in equal quantity. Only after the universe became transparent did these photons become free, and since they were produced roughly homogenously in that soup there are everywhere in the same quanitity: a background radiation. Since they were not produced in a localized event, they won't have a center. But since they're everywhere, they are a sort of absolute reference for how fast you're going (actually that's a new and interesting idea for me too, pretty neat).
- mensetmanusman 6y agoYou are re-experiencing the thought process of Einstein. The recognition that there are consequences to our understanding of time if the speed of light is constant in every reference frame was earth shattering in the science community a century ago.