object that is actually at rest? - Page 1
Forum section: electronics / projects

author: coppercone2
author_rank: Super Contributor
timestamp: September 30, 2023, 06:28:25 pm
content: So the milky way is moving 600 mps, in addition to all the rotations and stuff going on.Is there any matter int he universe that is.. I guess relatively well isolated from this?As I see it, basically the milky way is a car, we are throwing objects inside of a car.Can a buoy be made (with thrusters) that keeps it in the same spot? It seems that everything is moving since the big bang or whatever they are saying now.I assume this object would appear to fly away from an observer very quickly.Because it strikes me as odd that all the matter that we know of is actually in motion. If we stabilize something its still moving with the galaxy.

author: TimFox
author_rank: Super Contributor
timestamp: September 30, 2023, 06:59:08 pm
content: This is the fundamental difference between Newtonian mechanics, where Newton believed in an absolute reference frame with respect to which other object moved, and Einstein's relativistic mechanics, where all "inertial" reference frames are equivalent.The simple definition of an inertial frame is that is not accelerating: this is a subtle concept that Einstein demonstrated with Swiss trains.Rotating objects exhibit acceleration: the velocity of any point on that object is being accelerated to maintain its rotation.In simple "Galilean" relativity, one can only see relative velocity between objects.The black-body residual radiation can be interpreted as defining the "rest frame" of the universe.

author: coppercone2
author_rank: Super Contributor
timestamp: September 30, 2023, 07:14:10 pm
content: well when you think about it in terms of motion of galaxies and stuff it seems like more that its hard to figure out how to apply a counter force to make it stiller.IDK about acceleration, more like velocity. They know the galaxies are gonna collide and stuff that means their some where and their going some where. but it seems like you can make something stay where it is.

author: RoGeorge
author_rank: Super Contributor
timestamp: September 30, 2023, 07:18:39 pm
content: Quote from: TimFox on September 30, 2023, 06:59:08 pmNot sure if that's a different way of naming it, a typo or maybe something else entirely. Is that about measuring the Doppler shift relative to the cosmic microwave background?Later edit:Question clarified, found out that the cosmic microwave background is sometimes referred as black body radiation, which makes sense.(BTW, I didn't know it the Doppler shift was big enough to measure it. Googled the keywords from the quoted text, and found out herehttps://www.quora.com/How-can-one-measure-speed-relative-to-the-rest-frame-of-the-Cosmic-Microwave-Background-radiationthat we are moving relative to the microwave background at about 0.1% of the speed of light)

author: coppercone2
author_rank: Super Contributor
timestamp: September 30, 2023, 07:22:51 pm
content: isent the cosmic back ground moving since the photons are moving, they can't stand still.

author: RoGeorge
author_rank: Super Contributor
timestamp: September 30, 2023, 07:52:51 pm
content: They don't sit still, but it is assumed that the photons from the MW background are a result of the big-bang, when all was very hot and very, very homogeneous, thus that the MW photons were emitted the same, in all directions, and from each point of space. Or at least that's the accepted explanation for now.The thing is, when the MW background is measured, it appears to be the same no matter in which direction the antenna is pointed.Funny tale, the two dudes that first discovered the MW background (by serendipity) were driven crazy about the fact that no matter the orientation they were pointing their antenna at, that MW noise was staying the same. They were keep receiving some radio noise despite all their efforts (their task was to get rid of noise). At some point they even considered the MW noise was somehow related with the pigeon's poop in the antenna, and went to scrub that.Eventually, they won the Nobel Prize, after another dude told them that that noise they were trying to get rid of, was in fact the MW background, a proof of the big-bang theory, a theory mostly unknown back then. The dude who told the two guys what that omnidirectional noise was from, didn't won any prize.

author: Benta
author_rank: Super Contributor
timestamp: September 30, 2023, 10:23:35 pm
content: This explains the whole thing:

author: SiliconWizard
author_rank: Super Contributor
timestamp: September 30, 2023, 10:32:34 pm
content: Quote from: coppercone2 on September 30, 2023, 07:14:10 pmNot sure I quite get the depth of your musing here. Are you by any chance pondering the question of how to stop the universe from expanding?

author: ejeffrey
author_rank: Super Contributor
timestamp: September 30, 2023, 11:07:43 pm
content: Quote from: coppercone2 on September 30, 2023, 07:22:51 pmBasically there is a velocity such that the CMB looks about the same temperature in every direction. Increase you velocity in one direction and the CMB there gets blue shifted and thus hotter, while the CMB behind you is red shifted and colder.That's about as close as you can come to an absolute rest frame although it's not preferred or special by any laws of physics that we know of. It's just a way of sort of averaging over the observable universe. It's what people who are looking for violations of the principle of relativity (such as faster than light communication) typically assume would be the preferred frame if one exists.

author: David Hess
author_rank: Super Contributor
timestamp: October 01, 2023, 01:20:07 am
content: Quote from: coppercone2 on September 30, 2023, 06:28:25 pmSpace itself is expanding and there is no "center". Imagine the surface of a balloon as the balloon is inflated; every point on the surface is moving away from every other point.At any given point you can measure the velocity at a fixed distance and so "cancel" your velocity so that you are still, but so can every other point, and you will be receding from those points as space expands.Galaxies and galaxy clusters have enough self gravitation to dominate local movement, so they are not expanding within themselves, at least for now.When we look at the cosmic microwave background, we are seeing something that in the past was much closer, and actually adjacent. We are really seeing the past, and the redshift is caused by the expansion of space between that point and us. Go further and the redshift exceeds the speed of light and forms an event horizon, and nothing can be seen.

author: coppercone2
author_rank: Super Contributor
timestamp: October 01, 2023, 03:12:48 am
content: but if you have a ant on a balloon it can walk over to where it was. it just stands on thinner rubber. it would detect that the ground under it is thinning and simply step to where it felt that it was

author: IanB
author_rank: Super Contributor
timestamp: October 01, 2023, 03:58:43 am
content: Quote from: coppercone2 on October 01, 2023, 03:12:48 amI don't understand this statement. Can you elaborate?

author: RoGeorge
author_rank: Super Contributor
timestamp: October 01, 2023, 05:49:19 am
content: Quote from: coppercone2 on October 01, 2023, 03:12:48 amThe balloon analogy might be misleading because of the stretching in the rubber molecules.Instead of that, I prefer to think that in time, new "particles of space" pop into existence, thus the dilation of the universe and the stretching of light wavelengths. This avoids the conflict of apparently "faster than light" speeds outside the visible universe.No matter how you put it, some idea of "sitting still" reference frame is embedded in those analogies, which reminds of the idea of aether, which is heavily rejected by mainstream physics.As for a "sitting still" object, that would be a very twisted trajectory relative to us, because the Earth is spinning around its own axis (even more, a tilted one), then spinning around the Sun, and the solar system is spinning with the galaxy, and so on.Talking about the kind of trajectory in the animation shown at 19:51 (and in the video thumbnail)https://youtu.be/IJhgZBn-LHg?t=1191How Earth MovesVsauce

author: coppercone2
author_rank: Super Contributor
timestamp: October 01, 2023, 06:08:27 am
content: if new particles are forming its kind of like floating on top of a pipe that is ejecting water (flooded manhole) that is spreading out in all directions to flood the area. It still seems possible to remain floating right on top of it. It seems to me if anything new is being introduced you are simply trying to over come a drift current. If its stretching I guess that is also a current/flow.that is also bizzare to me because how many source points are there for new particles to be created. The idea that something is changing phase, stretching, etc.. is much more plausible to me. So then it makes me think that there is particle spawners aligned on some fixed grid that fill in the gaps? not sure what these particles are either. quantum foam? then you have minimum spacing ?And even if everything is spinning I am guessing a still object would have to end up rotating (from our refernece frame) to be still. I don't think it can follow any curvature because that would imply its coupled to something I think. It could spin and also move at some direction? im not sure about the cork screw motion at its final resting position. I think it would appear to be spinning and moving away from us in a strait line. Maybe I am missing something about precession. that one is weird.

author: Microdoser
author_rank: Frequent Contributor
timestamp: October 01, 2023, 09:38:00 am
content: An object completely at rest would still be moving forwards in time at the speed of light. Einstein proposed that time is a dimension (t) that we move through to experience time. This concept is why time slows down when you move in other directions (x,y,z) close to the speed of light,your speed is always constant, you just share it between moving in space and moving in time. So if you could move at the speed of light in a spacecraft, time would stop for you. If you could stop your x,y,z motion completely, time would happen at its fastest possible rate (1 second per second).Stopping is not an option, slowing down is not an option. All you can do is change the direction you travel.

author: jpanhalt
author_rank: Super Contributor
timestamp: October 01, 2023, 11:03:47 am
content: Is this really a "Project, Design, and Technical Stuff?" I'd have a hard time fitting it even in "Dodgy Technology." All motion is relative. Here is an interesting, more technical discussion:https://physics.stackexchange.com/questions/192891/if-all-motion-is-relative-how-does-light-have-a-finite-speedWill the originators of such spam be convinced by anything? I doubt it.

author: EPAIII
author_rank: Super Contributor
timestamp: October 02, 2023, 12:19:47 am
content: This is the exact stuff that brought Einstein to his theories of relativity. That background radiation may change wavelength if you are traveling but it's measured velocity stays exactly the same. Thus a "stationary" observer and an observer who is moving at a high velocity to that "stationary" observer will both measure the velocity of that radiation as having the same value. And that is true no matter which way they measure it in: left or right, up or down, forward or backwards (x, y, z -x, -y, or -z). This is so counter-intuitive that many, perhaps most other scientists had to be brought to that point of viewkicking and screaming. There were a multitude of alternate theories proposed to explain things in other ways but they all failed. So, if you find this hard to understand, you are in good company with some of the most brilliant scientists of the last century.For better or worse, the others were proven wrong so relativity is now the "law of the land" in physics. But even that is not a real law and we are now finding even smaller differences between what relativity predicts and what we are observing. So even more advanced theories are coming up to supplant those of Einstein.One thing that I have observed about science is that it is NEVER settled. When you hear someone loudly proclaiming that, "The science is settled!", you can quietly tell yourself that person knows little or NOTHING about science. And "laws" of science are NOT actual laws. They are not carved in stone. They are only well established theories that will some day be replaced with better theories.The answer the the OP's question about anything being "at rest" is no, we can never say that anything is "at rest". Everything moves, relative to other things. Perhaps not all other things, but relative to some, everything moves. And that "some" can and often will be different for each object you consider. And no object or group of objects can ever lay claim to being at rest in an absolute sense.Quote from: David Hess on October 01, 2023, 01:20:07 am

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 02, 2023, 01:09:34 am
content: As long as there is energy in the universe, there is no "rest". And is there any universe to speak of if there is no energy?

author: switchabl
author_rank: Frequent Contributor
timestamp: October 02, 2023, 09:28:22 am
content: Quote from: Microdoser on October 01, 2023, 09:38:00 amI think the geometric approach to space-time is due to Minkowski, not Einstein. And to me, the picture you paint is a useful analogy but I'm somewhat worried that trying to make it into more than that and even re-defining speed as the norm of the four-velocity might be stretching the original concept of "motion" rather thin. It might also make it a little too easy to lose sight of the fact that spacetime is not actually Riemannian and even though we have scaled the time dimension by c to treat it on an equal footing with the space dimensions, there is still a fundamental difference due to the signature of the metric. This is purely a disagreement about didactics (and maybe philosophy), not physics, of course.Quote from: EPAIII on October 02, 2023, 12:19:47 amThere isa lotof settled science. Not in an absolute, epistemological way of course, but practically (and socially) speaking anyway. Theories aside, no one actually expects our experiments to turn out different tomorrow than they do today (the more reliable, well-replicated ones in any case). To put it bluntly, do you actually believe that the apple might fall upwards tomorrow?And some theories are constrained pretty tightly by experiment, so even if they end up being replaced, their core will likely live on in some approximate or limiting sense. Heck, Newtonian mechanics and classical electrodynamics have both been superseded by "better" theories but they are being used more widely, and successfully, today than ever.No one is going to abandon a successful and deeply entreched theory without some very convincing evidence either. Basically, unless you got something really solid, you're going to be laughed out of the room.

author: David Hess
author_rank: Super Contributor
timestamp: October 02, 2023, 01:36:03 pm
content: Quote from: EPAIII on October 02, 2023, 12:19:47 amThe science is settled in the sense that the theory which replaces Einstein's relativity has to make the same predictions, like relativity simplifies to Newton's laws of gravity.We know relativity and quantum mechanics are incomplete because they conflict, but they are still correct where they apply.

author: Microdoser
author_rank: Frequent Contributor
timestamp: October 02, 2023, 01:54:21 pm
content: Quote from: switchabl on October 02, 2023, 09:28:22 amWell, QM says it is possible, but the possibility of it happening is so small that it is not likely to happen in the lifetime of the universe. If we regard human experience and lifespans, that's practically the same as impossible. To restrict that to just tomorrow adds another level of unlikeliness.But an apple could indeed fall upwards tomorrow. It's just not very likely.It's far more likely that all the RAM in your video card would fail in the exact way required to depict a full colour photorealistic Donald Trump emulating a GOATSE image.

author: TimFox
author_rank: Super Contributor
timestamp: October 02, 2023, 02:20:50 pm
content: One possible scenario that had been discussed theoretically was if anti-matter would fall up in the usual gravitational field.A difficult experiment to perform, but it was recently announced that anti-hydrogen atoms (a positron orbiting an anti-proton) did, in fact, fall down.https://new.nsf.gov/science-matters/down-goes-antimatter-gravitys-effect-mattersIn newspaper articles, someone at U California Berkeley said that no one in his department was surprised.

author: Terry Bites
author_rank: Super Contributor
timestamp: October 02, 2023, 09:16:01 pm
content: Space is not static, its expanding (don't believe the current JW bullshit factory). Every point is moving away from every other . You cant fix anything to a moving point or a time come to that. The way things are going, the milky way will be chucking us out.

author: bostonman
author_rank: Super Contributor
timestamp: October 03, 2023, 03:01:31 am
content: I watched that 21min long video and found it quite interesting.From the video,and prior to watching it, I have a few questions. Our galaxy is circulating the sun, and, according to the video, traveling in a conic circle pulling away from the sun (or the video just left the sun at rest to show the trajectory of our galaxy).Did the video leave the sun at rest by accident or did I miss something?As for the universe "expanding", is all matter in the universe expanding equally meaning, are the planets expanding, us humans, my computer, car, etc... or is just the boundaries of the universe expanding and everything (planets, stars, etc...) remaining the same distance from each other?

author: RoGeorge
author_rank: Super Contributor
timestamp: October 03, 2023, 08:37:50 am
content: The Sun, and the entire solar system, is orbiting around the center of our galaxy. There's nothing special about the Sun, and it is not at a fixed point, it "circles" around the center of our galaxy, and the entire galaxy is moving too, relative to other galaxies, etc. So far it seems to be aGreat Attractor(like a gravitational "centre" when looking at the entire observable universe), but that's a recent observation, still in research.In a computer animation, one can pick any point where to put the camera, and that point can take the Sun as "fixed". Funny thing, when you attach a camera to something that moves, the video might look very unusual for us, who are used with a "fixed ground" as a reference. See for example this 3 seconds animated image with a camera attached to the track of a tractor. Play it in a loop.https://www.eevblog.com/forum/chat/fun-for-nerds/?action=dlattach;attach=815313Look at the yellow wheel(s). Notice how the yellow wheel normally rotates, then the rotation "instantly stops", as if it where no inertia!?!In that video loop there is no mystery of how's so, that a rotating wheel can (apparently) "instantly stop". Only bringing it to illustrate the weirdness that can arise from the movement of two reference frames relative to each other.As for the objects expanding together with the universe, my understanding is that the inflation is happening mostly for the empty/interstellar space, not for planets and stars and other objects. So, the computer, the Earth, us humans, do not "expand" with time.Keep in mind that I'm not a physicist, so I might have got some aspects wrong.

author: David Hess
author_rank: Super Contributor
timestamp: October 03, 2023, 08:18:38 pm
content: Quote from: bostonman on October 03, 2023, 03:01:31 amObjects which are gravitationally bound, including galaxies and galaxy clusters, are not expanding within themselves. So the space between distant objects which are not gavitationally bound expands such that those objects move away from each other, but objects which are closer are gravitationally bound and are not expanding away from each other.

author: bostonman
author_rank: Super Contributor
timestamp: October 04, 2023, 02:24:41 am
content: So the "walls" of the universe are expanding, nothing else?In other words, if we wanted to travel to the edge of the universe, it will always be escaping us due to expanding (at the speed of light?), but, everything else (galaxies, stars, planets, etc...) will always keep the same distance?My understanding is our sun doesn't move but moves as our Milky Way galaxy moves. So all eight (or nine) planets, moons, and the stars, rotate around the sun and the sun remains "still" but the galaxy is moving through the universe.I know things like our moon is slowly pulling away from Earth, but, regardless, does the sun move relative to our Milky Way?

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 04, 2023, 02:47:56 am
content: I've always wanted to take a sip, sitting on the edge of the universe, but this very thought keeps expanding.

author: coppercone2
author_rank: Super Contributor
timestamp: October 04, 2023, 02:50:34 am
content: if the walls are just moving you can still stay in the same place IMO. even if ratiometrically between the measured distance to each wall

author: IanB
author_rank: Super Contributor
timestamp: October 04, 2023, 03:50:05 am
content: Quote from: coppercone2 on October 04, 2023, 02:50:34 amMotion is relative. So if you can see something moving, then you are moving relative to it. The only way to be stationary is for nothing in your observable horizon to be moving (including distant stars and galaxies). Since it is effectively impossible for this ever to happen, it is effectively impossible to be stationary in our present universe.

author: Bud
author_rank: Super Contributor
timestamp: October 04, 2023, 05:32:13 am
content: You guys need a girlfriend. Return to the reality will be quick.

author: coppercone2
author_rank: Super Contributor
timestamp: October 04, 2023, 05:36:21 am
content: ooga oooga

author: Microdoser
author_rank: Frequent Contributor
timestamp: October 04, 2023, 01:04:38 pm
content: Quote from: Bud on October 04, 2023, 05:32:13 amSounds like you need a wife

author: bostonman
author_rank: Super Contributor
timestamp: October 04, 2023, 02:48:54 pm
content: QuoteHow can this be? If I'm sitting on my front lawn (i.e. at rest) and a car drives by, I can see it moving.In any case, ignoring that our solar system is moving through space, the sun remain still, correct?

author: IanB
author_rank: Super Contributor
timestamp: October 04, 2023, 03:01:36 pm
content: Quote from: bostonman on October 04, 2023, 02:48:54 pmBut if someone is sitting in the car and looking out the window, then they see you moving past the window as the car goes past. From their perspective the car is stationary and everything outside the car is moving past. Physics says that either perspective is valid.QuoteNo, even within the solar system the the Earth and the sun are orbiting around each other. If you think of an imaginary string between the center of the sun and the center of the Earth, then the Earth and the sun are revolving around a point somewhere along that string (which is somewhere inside the sun, but not at the center of the sun).

author: David Hess
author_rank: Super Contributor
timestamp: October 04, 2023, 03:17:59 pm
content: Quote from: bostonman on October 04, 2023, 02:24:41 amThe "walls" are the boundary beyond which nothing can have an effect on us because beyond that point space is expanding away from us faster than the speed of light. Since light from that area can never reach us, that area can have no effect on us.QuoteObjects which are far enough away not to be gravitationally bound are also moving away from us. If you were to travel 100s of millions of lightyears to a point outside of the Virgo Supercluster, or maybe the Laniakea Supercluster which includes the Virgo Supercluster, then the Milky Way and Sun, and entire Virgo Supercluster, would gradually recede with the expansion of space.QuoteThe sun, and objects gravitationally bound to the sun like its planets and moons, is gravitationally bound to the Milky Way so orbits the gravitational center of the Milky Way.

author: David Hess
author_rank: Super Contributor
timestamp: October 04, 2023, 03:25:25 pm
content: Quote from: bostonman on October 04, 2023, 02:48:54 pmYou cannot actually establish when you are at rest. Albert A. Michelson and Edward W. Morley tried that by measuring the speed of light in different directions. When at rest, the speed of light should be the same in all directions, right?Well, it does not work that way. What they measured showed that the speed of light was the same in every direction no matter what your velocity is.https://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experimentWe can be "at rest" in comparison to the microwave background radiation, but so can every other point in the universe and because the universe is expanding, those points are moving away from us. So no points are at rest and all points are at rest. "At rest" has no meaning when comparing observers at different points.

author: TimFox
author_rank: Super Contributor
timestamp: October 04, 2023, 03:38:36 pm
content: What you can do, however, is determine if you are beingaccelerated: an example would be a rotating reference frame.One of Einstein's important postulates is that the effect of a gravitational field is equivalent to being in an accelerating reference frame.

author: bostonman
author_rank: Super Contributor
timestamp: October 04, 2023, 05:25:31 pm
content: QuoteMaybe I'm confusing the terminology. I'm thinking the sun doesn't move meaning, unlike (let's just use one planet) Earth that is rotating and orbiting the sun. I assume the sun rotates, but does it orbit (again, ignoring that our Milky Way is moving through the universe)?I (much like I assume many) picture the sun as a sold non moving object with our eight (or nine) planets circuling it. This is also ignoring the miniscule distances things like our moon is pulling away from Earth, and, I assume, planets are not sitting in perfect orbit and are slowly drifting closer/further.

author: TimFox
author_rank: Super Contributor
timestamp: October 04, 2023, 08:16:20 pm
content: When you work out the orbital mechanics of the earth orbiting the sun, it is convenient to reduce the problem mathematically.If you look in any elementary book on classical mechanics, the two positions are replaced by an equivalent radius at which an equivalent mass orbits around an effective center: see textbook for details.Since the sun is far heavier than the earth, the effective center is well within the body of the sun, so the correction is small.When you deal with binary systems where the masses are not very different, this is a large correction.

author: IanB
author_rank: Super Contributor
timestamp: October 04, 2023, 08:24:15 pm
content: Quote from: bostonman on October 04, 2023, 05:25:31 pmNo, the sun is not a solid, non-moving object. If two objects are orbiting each other in space, like the sun and a planet, then they are each orbiting around a common center point, called the barycenter. So the sun is not fixed, it is experiencing orbital movement of its own.See here for more info:https://spaceplace.nasa.gov/barycenter/en/

author: TimFox
author_rank: Super Contributor
timestamp: October 04, 2023, 08:31:57 pm
content: That useful article points out that the "barycenter" for the Sun-Earth system is close to the center of the Sun, but for Sun-Jupiter it is approximately at the surface of the Sun.

author: Microdoser
author_rank: Frequent Contributor
timestamp: October 05, 2023, 01:27:02 am
content: Quote from: David Hess on October 04, 2023, 03:25:25 pmYou can't measure the speed of light from one point to another one way. You can only time how long it takes for light to do a round trip, so you'll never know if it took less time to get there than it did to get back, only the total time. Even if you get two perfect clocks to measure the time the light arrives and compare to the first clock, you have to match them up next to each other, otherwise the potential difference in the speed of light affects the synchronisation, and special relativity says that moving a clock changes what time it says, and the change is dependent on the speed of light, so if the speed of light is different going this way compared to that then your clocks will be wrong by a proportional amount.Michelson and Morley did their experiments before we knew about relativity, special or general, or they would have known this.

author: coppercone2
author_rank: Super Contributor
timestamp: October 05, 2023, 02:00:30 am
content: well I think the reference frame for still must be at zero velocity at the start of time / motion. A velocity at which it looks like everything is moving away from you.If you can put a ship in the middle of the big bang or matter incursion or whatever and measure the distance to the interface/surface of the expanding thing, then you can stay still, if the rates measured on all the sensors are equal. That is like hovering in the middle of a expanding balloon. There seems to be a very specific 'front' that you can use as a reference in this case.Would it not be like the center of mass point kind of?But its still confusing because how do you treat it, at first its a ball of high energy expanding quickly. It seems feasible to stay in the middle of that. But when it starts condensing and you have orbits between matter condensation, even if you stay in the middle based on some kind of boundary, it seems poorly defined on what is still at that point. The only thing that kind of makes sense to me is center of mass or net force cancelation, but its very confusing... some averaging comes to mind to remain statistically motionless despite their being complex minor motion.So it seems to me at least for a while you can stay still if you know the shape of the wave? front of the big bang/rip/whatever.

author: SiliconWizard
author_rank: Super Contributor
timestamp: October 05, 2023, 02:22:59 am
content: Quote from: coppercone2 on October 05, 2023, 02:00:30 amWhat is time?

author: coppercone2
author_rank: Super Contributor
timestamp: October 05, 2023, 03:23:32 am
content: WELL in that case it seems like when you can measure velocity

author: David Hess
author_rank: Super Contributor
timestamp: October 05, 2023, 07:15:15 am
content: Quote from: coppercone2 on October 05, 2023, 02:00:30 amAs I pointed out, the problem with what you suggest is that if I do the same thing for a another point at a distance, then both points by your measurement are at rest, but they are also moving away from each other.QuoteThe ship is on the surface of the balloon and not in the middle of the balloon.

author: Microdoser
author_rank: Frequent Contributor
timestamp: October 05, 2023, 11:51:31 am
content: Quote from: SiliconWizard on October 05, 2023, 02:22:59 amSome people think, based on the fact that when you fall into a black hole space becomes timelike, and inwards becomes forwards in time, that this creates a new spacetime where 'inwards' is the future, and the past leads to the event horizon. It neatly explains why there is a limit on the speed of light, for example.Anyway, this would mean that the answer to 'What is time' would be, 'it is the physical manifestation resulting from us falling towards a singularity that exists at the end of time'. We do this at the speed of light.