md65536

The relevance is that you accept that gravity applies beyond experimental evidence (eg. in your living room) but dismiss evidence of relativity beyond experiments. This view might make more sense if relativistic effects (like length contraction) were just parts of a theory devised to explain observations of high-energy particle experiments, which you've suggested that you believe. However, relativity is a theory devised to explain other observations... namely those of the speed of light, and measurements thereof in different forms over a century or two. Length contraction and time dilation are consequences of relativity and of the observations of light. The theory came before experimental observation of relativistic effects. Particle experiments support the theory; they did not spawn the theory. Yes, I think this is true. I think it makes the most sense to consider only the properties of time that you can reason about (and do so precisely, ie. mathematically), and ignore everything else (because if you can't reason about it or test it, you can't validate it, and there would be no way to tell what is "true" from what is simply made up, or what is "cloudy"). For me a good ontological study would begin with what you can experimentally observe about time, and end with what you can logically deduce -- or perhaps a step further into interpretation(s). If ontology requires more (determining "what it is" when any potential answer can't be validated or evaluated), then I don't think ontology has scientific merit, besides being a source of imagination that can inspire new ideas. If ontology exceeds experimental validation, it is similar to me to visionary science fiction. But I think this is an aspect of philosophy in general, where it is good to think of ideas without limits, whether or not those ideas can be experimentally verified. Philosophy considers the meaning of things, and if you're trying to figure out something like time, that can definitely make things cloudy.

Come to think of it, I think the technical name for that is "local frame of reference" (or perhaps "inertial frame of reference"?). You might say that every observer prefers their local frame of reference, but that is not the accepted meaning of preferred frame. Considering all frames, none are generally preferred over others.

Isn't this just what "frames of reference" are in general? Things in an observer's inertial frame are at rest relative to the observer. Problems with this definition: - Every observer's frame is a preferred frame of reference, since every observer is at rest in their own frame. - How do you measure the distance between moving objects? For example, consider measuring the distance between 2 rockets moving away from each other. Where is the preferred frame, at rest relative to that which is being measured? I'm glad to see some specific ideas besides "SR is obviously wrong".

I must conclude that my initial idea was wrong. We can define space in such a way that it is defined for nothing, simply by having the definition not depend on things like matter. More practically, we can consider distance in terms of curvature, and discuss what curvature is like away from matter. I think that GR might not define curvature in the absence of all matter, but it does define curvature remote from matter, to any distance (since spacetime is homogeneous). ? I still "believe" that spacetime might not be homogeneous and there is some way to express some kind of curvature where distance "ends" or something, but this belief is based on ignorance. But I think there may be some insights into the topic in the question of "How would you measure a distance of nothing without sticking any matter into it?" (I think it's an interesting question, because if space curves due to matter, then measuring it with matter changes it, and then the real answer might be the answer to another question: "Do we assume that measuring space changes it very little, due to assumptions, or due to extrapolation?") So back to the question of how might we measure distance where there is no matter? If you beam photons into it, you will never get information back from them? Is there a way to beam energy into a void, and have it change direction without interacting with anything? Perhaps you can have something photon-like that decays into other photon-like energy that is emitted in different directions, at least one of which can be intercepted? Or perhaps shooting 2 converging beams into nothingness... would you be able to detect information from the point of convergence? And is putting energy into nothing the same as putting matter into it?

I'm surprised that you never came across these answers while studying SR in depth. I find that sometimes, pages of books I'm reading get stuck together and I skip over things without even realizing it. You might look over your notes to check for this. Perhaps you accidentally skipped a few chapters. Since you have studied it in depth, you will know how length contraction follows as a logical consequence of the principles of relativity, and you will know what observed evidence must be incorrect if length contraction is false. EDPP... I like it. It's less confusing than "time" and it's clear from the words exactly what it means (ie. it means what we really mean when we're talking about "time"). It doesn't roll off the tongue quite like "time"--I will pronounce it "Edpeepee"--but it is good. Of course, the Edpeepee still varies due to relativity; that is, the durations can be longer ie. dilated, but since the wording is clearer we can know that we don't have Edpeepee reification, when we say that it is a logical consequence of the principles of relativity and a fact of nature, that "Edpeepee dilates".

I believe it because it does vary. The distance between Earth and Sun is the distance between Earth and Sun according to any observer. Distance between Earth and Sun varies even without length contraction since Earth's orbit isn't a perfect circle (wikipedia says "The Earth is 1.00 ± 0.02 AU from the Sun").But an AU is defined as a number of meters, which vary due to length contraction. What doesn't vary is c, which I think is key to grounding all of these concepts and making them meaningful despite all the variability. Curses! You've once again proven me a fool by my taking of your bait and replying to your posts!

I'm currently siding with the opinion that information that does not have an effect on anything else, does not exist. Is this true (or false) based on definitions ("exist" etc) or scientific laws? Why I think it's true: - If it has or can have no effect on anything, then it doesn't matter if it exists or not (there is no difference in the observable universe), and it seems like existence would require such a thing, by definition. Why I think it might be false: - Conservation laws; symmetry etc. If you have energy and you lose it, you know by conservation laws that it is not destroyed, and you can deduce that it still exists. I don't think this is valid, because it would require an assumption of the existence of things we have no way of knowing anything about. If we know that some energy has been lost (if there is some evidence of it left in the known universe, this constitutes a "memory" of the information, which might be considered an observable effect of the information??? This might require the distinction between "observable information", "deducible information", "lost information" (unknown information that might be found again), and maybe "destroyed information". Examples: - If you beam light into deep/empty space, and in the case that it may never come back, is that information lost? If it doesn't interact with anything, it is undetectable(?). Wouldn't this have happened with the big bang, where a lot of light would have escaped and continued outward forever, with no way for us to measure? Is there some unknowable amount of energy that is assumed to have escaped the big bang, or are there clues left behind to be able to determine the total energy of the big bang? - If you send a light signal across empty space (say from Earth to moon), that light does not seem to exist except where it is sent and where it is received. For the duration of its "flight", the photons have no effect on anything, and they are undetectable (except by something that changes their destination, in which case they still only exist where they have an effect). There is no observable difference between photons flying from one place to another, vs. photons jumping from one place and time to another. - If an event is completely forgotten (no memory of it, not written down anywhere, no evidence of it, no lasting effect on any energy or particles), is there any meaningful definition that says the event actually happened? This might get into many-worlds interpretation etc. - If you have 2 entangled particles and lose one, can you deduce the existence of the lost one from the known one? Are there such clues about all possible particles, found in all known particles?

Imagine a circle. What is it made of ("the ontological problem of the imaginary circle")? Is it curved? Can things that do not have physical presence (ie. non-entities) be curved? If no, then how did your imaginary circle become real? The difference is that in one situation (eg. due to gravity), all clocks slow down... ie. time dilates. In the other (eg. under water), not all clocks slow down. So for example if you put a clock underwater you can see that it's slowing down, but if you're traveling at near c with a clock, you can't see any change in time (in fact there is none relative to you) because your brain is also affected the same way that the clock is. Time dilation is only experienced relatively, from other frames of reference. AND because there is no privileged frame of reference, you cannot say that a clock is absolutely slowing down, from within an inertial frame of reference. If this doesn't make sense, it is because relativity is a very confusing thing to get, at many different levels (from general concept to exact details of particular examples), and you're not going to understand it without researching it. I could not and would not try to explain it all in an internet forum. All this evaluation of wording is beside the point. The point is: - time is well-defined and consistent - its definition is meaningful, in that it applies to aspects of real-world observations (unlike your example of auras and aura-meters) - it is complete in that the definition ("time is what clocks measure") does not fail to account for any "time-like notions of reality". Sorry my wording is not exactly scientific. Any proposed evidence to the contrary would be interesting.

Well, my reasoning is as follows: - Distance seems to be defined between any 2 points in space. - Distance also seems to be defined "around" matter, since mass curves spacetime. But to what extent? There seems to be no intrinsic limit based only on length (distance from the mass). I don't have a firm handle on curvature but I think curvature due to mass approaches 0 (flat) as distance approaches infinity, but it is still non-zero at any arbitrary distance??? - However, there is an intrinsic limit to distance based on time. A mass cannot have any effect on anything outside its light cone, ie. no information can travel faster than c. This is the law of causality. To me it means that a mass cannot define the curvature of space at a distance farther than where light (or eg. gravity waves) could be able to travel in the time that the mass has been around. In other words, space could not be defined farther than c * age of the universe away from any matter (even if inflation allows the matter to escape other matter's "causal horizon", which might allow for "gaps in space"). That spacetime warps (consistent with SR and GR) is a fact of reality that I accept. The universe appears (to the limit of our measurement) to be flat*; these are not mutually inconsistent statements. I don't understand it enough to say why. If there is infinite matter in the universe (which I don't believe is true) and it's evenly distributed, then distance would be defined to infinity in any direction. * Admittedly, this is pretty meaningless, because it's like saying "To the limit of my vision, the Earth appears to be flat." I agree. I believe that there's a finite amount of mass, all within some distance (related to the big bang), and that spacetime and distance is not defined beyond some limit (the union of all causal horizons of all matter and energy in the universe, I guess), and that spacetime is probably flat instead of closed. I don't think that all these beliefs are mutually consistent, and I'm missing some understanding of the meaning or implications of curvature, or mixing up the meanings of a flat universe and flat spacetime.

Distance can be defined abstractly, so that the distance between imaginary points is still defined, and this doesn't depend on what space is defined as (because we can always (maybe???) define an abstract space as well that is infinite and covers any "nothing" we want to consider). It seems that if space is flat (infinite) and homogeneous and isotropic then an abstract definition of distance would match a real definition of distance? Then, even if we couldn't measure distance in nothing without putting something into it, we could extrapolate it. This relies on the assumption that spacetime curvature is homogeneous to an infinite distance in any direction, which kinda implies that infinite distance is defined. I'm confusing myself now, but there must be something in this statement. Matter causes spacetime curvature at a distance. That curvature can be measured or extrapolated. Or is spacetime curvature the same as distance, and could be argued to have no meaning except between given reference points? Without figuring out the meaning of nothingness or space, I would guess that the calculable effect of spacetime curvature caused by mass would allow for a definition of distance, and this curvature is defined within the light cone of that mass. So I think that on the "real" end of the spectrum, distance is measurable between points of matter, and on the "abstract" end of the spectrum, distance is defined abstractly in an infinite flat geometric space, and somewhere in between, there is spacetime, which is defined only within the union of all light cones of all matter, and that distance is defined throughout and only throughout all of spacetime. But then, I don't know whether or not nothing would be defined to be exclusive to spacetime, or within spacetime, or both. I think you would have to allow nothing within spacetime, or spacetime would have to be considered "something" and there's no good reason to do that. Alright I've talked myself in circles but it comes back to the original idea: Even if distance is only defined between things, doesn't all matter "radiate information" (for example in the form of gravity waves) that define distance within that matter's light cone, all around it? Or does information only exist if it causes an effect -- only if there is something out there to receive it?

This is a digression of the "ontology" thread... Can anyone think of a philosophical reasoning that this wouldn't be true, specifically by describing some definition of distance that has meaning without the presence of matter? How could you possibly measure (or express) distance of nothingness? Isn't 1m between nothing the same as a billion light years between nothing? How can you measure distance without using matter? If you stick a tape measure in it, the matter of the tape measure defines distance. If you shine a light into it, you receive no information back (unless spacetime is closed). Is there any example of distance that is defined without requiring some form of matter at its extremities?

Yes, if you consider something being affected by something else to be a measurement. It is not meaningless. Speak to a scientist about time dilation and they will know exactly the meaning of the words, and the math as well, so the meaning can be precisely used. How is "Clock variability" more meaningful? And the same with space. Remove all entities and nothing is all that remains. If something real or physical remains, it is by definition an entity. Edit: I've been thinking... that the best way to do a "ontological analysis of time" is to first understand as much of currently accepted science about time, and see why it is accepted, and see that it is experimentally backed up, and see that it makes sense. It is helpful to let go of any preconceptions about time that you may have. Do not get stuck on unanswerable questions like "but what is time, besides what I can know that it is?" Be aware of what time and related concepts are defined to be, vs. what are experimentally observed consequences, vs. what is an interpretation. Philosophically, you may have some success with the interpretation part of it. If you can find a simpler interpretation, or better yet find a testable consequence of an interpretation, you'll get somewhere. You'll get nowhere assuming that theories backed up by experimental evidence are wrong. For example, one interpretation of time might be that "the future has already happened in some other dimension" or whatever, but that is neither a part of the theory of relativity, nor an observed phenomena -- ontology can easily challenge it and provide alternative interpretations, but it can't challenge observed phenomena without providing a valid explanation for what is observed. Time is what is measured by clocks. By definition, what clocks measure is time. All of these things fit together perfectly like an intricate invisible puzzle. I get the sense that you want to see exactly what time is, and its elusive or ethereal scientific explanation is unsatisfying. The "ontological analysis" that you speak of seems to be nothing more than scattering the pieces of the puzzle, and then being asked for them to be put together in a more visible manner. All the "sciencey" replies to your questions involve the pieces being put back together as they were, as they work. All I see resulting from the ontological analysis is meaningless questions. What are some (or even one) useful results of the analysis? What progress has been made in it?

A single 1cm "row" of glass molecules would have 10^7 molecules. The number of interactions of transmitted light could be far less (if photons bypass most molecules) or more (if photons interact with multiple rows of molecules). Smaller wavelengths (violet) refract more than longer (red) so the former must involve more interactions. Have scientists observed or modeled the path of photons and the number of interactions? If a photon is absorbed and then re-emitted when passing through glass, it would still have to obey causality. I assume that if a photon is absorbed at one point and time, and emitted at another point and time, the energy that makes up the photon will be found to have traveled some distance at a speed of c. Uncertainty might disagree with that. But I suspect that both uncertainty and causality apply: The exact location of energy is uncertain, but where it is observed, it is observed to have traveled at a speed of c. Does it make sense to speak of the path of photons between when they are absorbed and re-emitted? They might not be considered photons after being absorbed. It might not even be the same energy that gets re-emitted??? But if it does make sense, you could call the path of the energy a curved path along which the energy travels at a speed of c? The conjecture seems to be compatible with the principle of "least time". The principle says that the path of light takes the least time to get from P to Q while traveling at different speeds through different media. My conjecture would state that the speed of light is constant through all media, and follows a path of least distance (and thus least time) getting from P to Q. Since the distance inside the glass is different due to curvature than the same distance measured by an external observer, it doesn't appear to be the least distance to an outside observer. It might even be the case that the bent path "feels" straight to the photons??? A traveling photon (imagined to be moving in some pseudo-classical sense) might not experience any change in direction, nor any interaction with molecules, when passing from air to glass, but might instead experience a sudden warping of space as it passes from the spacetime curvature of one medium to the curvature of another. Infinite length contraction makes this impossible to imagine, and possibly meaningless. However, this doesn't seem to be compatible with reflection, and I would assume that the behavior of reflected light is very similar to the behavior of refracted light, in terms of photon/matter interaction.

Part 1: Slow glass... From a thread in the Relativity forum: http://en.wikipedia....ight_in_fiction "'Slow glass' is a material where the delay light takes in passing through the glass is attributed to photons passing '...through a spiral tunnel coiled outside the radius of capture of each atom in the glass.'" Suppose you had complete control over the path of light through some volume. Even with light traveling at c, a long curving path would take longer for light to travel, and could be used to delay light. A fractal path on an arbitrarily small section of a plane can have an infinite length. Quantum limitations might make a true fractal path impossible, but using arbitrarily large volumes of "slow glass" and being able to cross paths and use 3 dimensions should allow you to make an arbitrarily large path for light. If you had the path determined by some repeated crystal structure, such that the path of light entering from any specific angle at some specific point, would be the similar to the path of light entering from the same angle at any other point, you might be able to implement slow glass (possibly restricted only to a specific incoming and outgoing angle, eg. you might make it work only for light that is normal to the surface). Part 2: Refraction Can refraction and the "slowing of light in a physical medium" be described as the light traveling a greater, curving distance through the medium than it would if it were traveling through a vacuum? My (poor) understanding of refraction is that photons traveling through a medium with an index of refraction > 1 will interact with chains of molecules one after another, making light appear to have a speed lower than c, when instead it is just being delayed due to these interactions. But I can't make sense of that. The arrangement of molecules should make light behave differently depending on its angle through the medium. How can light through eg. glass be so perfect unless every path of given length through it intersected with the same number of molecules, regardless of direction? How could the atomic structure of glass be so isotropic? INSTEAD... I imagine that, say you have a 1 cm thick pane glass, then the distance across that pane, as measured from inside the pane, is greater than 1 cm. It might be that the path of light is simply curved or bent in some uniform way as the light interacts with the matter (ie. all glass is a type of "slow glass"). Another possibility is that the matter of the glass curves its interior space so that what appears as a straight line of 1 cm from outside, becomes a straight line greater than 1cm inside. Then light need not directly interact with the matter; it just follows a longer curved path through a vacuum inside the glass (ie the mostly empty space between the subatomic particles of the glass), and the length of that path is determined by the curvature caused by the matter. Can anyone imagine this? One problem is that refractive index depends on light wavelength, so the curvature of space within a medium would need to be variable. I can imagine curving spacetime looking like a curved funnel of typical spacetime "rubber sheet analogy" drawings, with different wavelengths of light going on different locations on the funnel, resulting in different distances being traveled through the glass. To rephrase the conjecture: Matter causes local spacetime curvature, that causes light of a specific wavelength to travel a longer path through the medium than it would through a vacuum. Then it's easy to conjecture that if a material is opaque to light of a certain wavelength, that means that the curvature is too extreme for the light to escape, similar to a black hole. Could the absorption of light energy be equated to light entering a black hole?

Suppose you have some space and you take everything but the space away (if such a thing is possible). Does the space still exist on its own, independent of all other things? If yes, then it is an entity. If no, then Einstein's quote holds (sorta... the quote speaks of space without "matter" while I'm speaking about space without "everything"). If it's impossible to take everything out of space, then space can't exist on its own. So the quote holds. No, it does not imply that at all. What if we didn't call it "time dilation", but instead called it "time differences"? Does that make time an entity? What if we just called it "differences in the measurements of the rates at which clocks tick in different environments"? Does that make time an entity? Does giving something a name (like "time dilation") give it a physical presence? I really think you're making a huge imaginative and misunderstanding-filled jump from "statements about time" to "time is an entity". I think that SR/GR is closer than you think, philosophically, to your own beliefs about time. I think that because SR makes claims about time (or the measurements of clocks) that you don't understand, you are assuming that it's claiming that time is a "thing", when really it is not. Time dilation does not imply that time is an entity.

I think the general idea's worth investigating, but I disagree with your details: - The properties of antimatter are actually very similar to matter, in terms of visibility, behavior, mass, etc. The only thing different is charge, as far as I know. - Antimatter annihilates with matter. If you are conjecturing that this involves moving to a different "time zone" or dimension or whatever, then what happens to the matter that is also annihilated? ALSO, annihilation releases a lot of energy, consistent with e=mc^2. Though it disappears, there's nothing missing when its gone. - The properties of known antimatter are fairly well known. If a lot of dark matter is made up of antimatter, it's not made up of "regular" known antimatter. But I think that's okay; we don't know the properties of dark matter, and I don't see why it couldn't be antimatter or somehow related.

Given your definition of dark matter as "matter", can we assume that there is also an antimatter equivalent? "Dark antimatter"? And since dark matter doesn't interact with matter, I presume it wouldn't interact with antimatter??? (Or would it? Would it annihilate, which is a different interaction from EM force interaction???) Dark antimatter probably wouldn't interact with antimatter, and might also not interact with matter, nor with dark matter. This doesn't help explain dark matter at all, but it might provide a possible explanation for why there seems to be so much more matter than antimatter in the universe. If all the antimatter is hiding in the form of dark antimatter, it might be possible that the total mass of matter equals the total mass of antimatter. I would guess that dark antimatter (vs dark matter) would be as scarce as antimatter is vs. matter. However, if matter can be converted into dark matter and/or vice versa, then some version of the OP's conjecture might be tenable.

Be careful with your terminology. Time is the measurement. Otherwise we'll be mired in questions like "an artifact of a measurement of what?" and that gets you nowhere. Then all your questions could be answered and you can still imagine there must always be something more to wonder what it is. Okay so I thought you were saying that time must be something more than what SR/GR says, but are you instead saying it is something less? Again, I believe it is a mistaken interpretation of SR to say that it suggests that time is an entity, or even that it is unexplained. If SR/GR's definition of time is no good, what can be added, changed, or removed to improve it? What specific observable (measurable) phenomena might be predicted differently by GR vs. this new definition (Note that all observed phenomena so far are consistent with GR)? If none, then how would you clearly describe the difference between the new definition and GR's definition of time, precisely enough for it to be useful? My point is, how can you define time by anything other than that which can be measured (ie. by a time measuring device)? If you propose some aspect of time that is not a consequence of what is observed, then how can you evaluate its validity? On the other side of the issue, if you propose some aspect that can be removed from GR's definition of time, how do you account for all of the observed phenomena that are consistent with GR? Well sure... the box can define a space. But I think Einstein was talking about removing everything, including such a box. Einstein's saying that space and time don't exist on their own. If something exists on its own, when considered as independent of other things, this implies that it is an entity (by the very definition of entity), agreed? But time is not an entity, agreed? Therefore, time does not exist on its own. Similarly space is not an entity, agreed? Therefore, space does not exist on its own. If you agree with all these things, where's the problem with Einstein's quote?

Partly, technology adapts to fit our lives, and partly our lives adapt to fit available technology. To replace all passenger jets, you're talking about a major change in lifestyle. The world would be a very different place. But I think people and lifestyles could adapt to it. I envision a future that has overlapping phases of both increased technology (and travel speed), and reduced resource use due to scarcity. That might involve perhaps "floating cities" that use wind power or similar, where people can freely drift all over the world, while at the same time there may be space planes that get you anywhere in an hour, but that are only used by few people or in rare circumstances. This is a very different lifestyle than the "work in one place; get away as quickly as possible" lifestyle. Anyway, there are a lot of possibilities to imagine. I think that the only thing that would reduce the number of people traveling or greatly increase the travel time, would be resource scarcity, and when that happens it will happen along with some major changes in lifestyle and technology. Hopefully it would be evolutionary and not disruptive.

It's conceivable, but I doubt it, because... 1) Anti-matter looks and behaves like normal matter. If dark matter can't be detected, making it antimatter doesn't make its invisibility any more explained. 2) Large amounts of antimatter probably do not exist in observable space. If they did exist in places, we would likely see evidence of annihilation of matter and antimatter in such areas or along the boundaries between areas of matter and antimatter. Oops... I didn't realize that your conjecture goes beyond this. Perhaps "dark antimatter" is different from antimatter, but evidence suggests that matter and antimatter have no problem coming into contact.

That which clocks measure, dilates. ie time. If that's unsatisfactory, can you give us a concrete example or speculation or anything of what time might be other than "that which clocks measure"? Is there any reason to suggest it is something more? And a follow-up: Is there any observable or testable prediction or consequence (even if indirect) of such an expanded definition of time? Or is there any way in which you can notice the effects of time, for which it is insufficient to say that it is "that which clocks measure", so that the definition of time used by SR/GR is insufficient? And, in case there is no way to notice the effect of any consequence of an expanded, ontological definition of time, then how would you verify that it was true, especially versus any other supposed ontological definition of time that also can't be verified or falsified, including of course the obvious possible case that it is nothing more?

I should have omitted "mechanical". Clocks ticking at different rates due to relativity are not due to any sort of error. Clocks ticking at different rates will not remain synchronized. GPS corrections etc involve re-synchronization of one frame's clocks to another's, not correcting for errors in time-keeping. It is malleable in that it is adjustable, even controllable (though neither easily nor arbitrarily, but it certainly happens as an everyday phenomena on a negligible scale). It adjusts to changing circumstances. "traveling forward through time" has the same meaning as "time travel" except it is limited to change in the same direction of the arrow of time. It does not imply any extra "stuff". If the word "through" bothers you, I'll change it to "one-way time travel". If that still bothers you perhaps you can define what you mean by "time travel" in a way that doesn't evoke "stuff". Going backwards is more complicated and really depends on what you mean to even begin discussing if it's possible. For example, universal time doesn't exist according to SR, so having everything go backwards in time while synchronized by all (universal) observers is impossible. An individual particle might be able to go backward in time. Some types of time travel might be possible with faster-than-light travel, which is itself impossible. I would say a safe bet is that any type or meaning of "time travel" that breaks the rules of causality, is impossible.

The Earth orbiting the sun can be considered a clock. All clocks experience the same relativistic effects under SR/GR. Different clocks tick at different rates due to relativity*, not due to mechanical error. Yes, different clocks ticking at different rates can be considered correct. But wait, perhaps you are right. The Earth orbiting is a really big clock, and I can see how that would make it authoritative. The solar system is our homeland. Obviously it should be treated as a privileged frame of reference, even though theory and experiment show that there is no such thing. Even if we say we accept the principles of relativity, the theory must be wrong because I still don't get it. I suggest we get the word out by spamming science forums on the internets. Then again... in your example, every observer agrees that 10 years and 10 orbits have occurred in the Earth frame while the rocket was traveling. Some just see that happening faster than others. Everyone is still correct. * In that sense, time can be considered somewhat malleable. If you consider "traveling forward through time at different rates" to be time travel, then time travel is an experimentally verified reality.

Hasn't this issue been addressed literally trillions of times in these forums, for this issue and an essentially identical issue regarding "space" as well as "time"? I'm no expert but I'll stab at it once again: SR and GR deal specifically with the rate at which clocks tick. The essence of time according to GR is that time is what a clock measures. Einstein defined time (as far as he dealt with it) as what clocks measure. And by clock I mean anything that measures time. A mechanical clock is a clock. A person is a clock, with their age a measurement of time. Rotting fruit can be a clock -- obviously some of these are more precise than others and some of them vary greatly depending on the environment. But here's the thing: constant velocity is not an objective aspect of the environment, yet relative velocity precisely affects the rate at which clocks tick. I'll explain what I mean: Velocity is relative, which means that if you have 2 inertial frames moving relative to each other, neither frame is "preferred", ie. neither frame can be said to be absolutely at rest while only the other is moving. Practically, what this means is that any clock you have has no absolute meaning of being at rest vs being in motion, and is therefore unable to detect any clue about such a non-existent thing, and therefore behaves the same relative to an observer in its same inertial frame whether it is at rest or moving relative to another inertial frame. Therefore, different clocks in the same inertial frame will not behave differently from each other due to relative motion vs another frame. If you have 2 otherwise identical environments, such as rocket interiors, all clocks will keep time the same in them whether moving or at rest relative to something else. (Anything that makes the frame a non-inertial frame can be an exception, so you may have clocks that "behave weird" during acceleration phases. Mechanical pendulum clocks should behave differently under acceleration. However, these cases are exceptions, and SR and GR apply to the general case, so we don't have to go into these exceptions to discuss either the consequences or the validity of SR or GR (which can deal with the exceptions anyway)). In summary the choice of clocks or the mechanics of those clocks don't matter. SR/GR applies to all clocks. Now, you are certainly more concerned about "what time really is" and all that, beyond "time only as measured by clocks." But GR is NOT concerned with that. For one thing, time as measured by clocks is ALL that GR needs, as far as being a theory. For another thing, GR does NOT imply anything more than that about what time "is". It would be a MISTAKE to derive a greater ontological meaning of time more than what clocks measure, from GR, because it simply does not say more about time than that. And this is a mistake you've made. If you have interpreted GR as making specific claims about time being some "thing" or whatever, something more than what clocks measure, then this is an interpretation of GR, and not a part of the central theory. Certainly, there are multiple possible interpretations of GR, and the interpretation (ontological aspects?) have not been settled. The accepted interpretation will certainly change over time (especially since it's not exactly complete, as far as I know). Your ontological study of time transcends GR. But certainly, your interpretation of time must account for GR in one way or another if it has any chance of being correct, because GR is experimentally supported. In summary: Interpret time however you may wish, but 1) you may not be able to prove that certain ontological aspects of that interpretation are correct, yet 2) if your interpretation does not agree with GR then it can probably easily be proven incorrect (unless you can experimentally prove GR incorrect). Perhaps you can consider GR's implications of time as a minimalist ontological description of time, that any other ontological interpretation must accommodate. Assuming GR says more about time is a mistake. Asking people to explain how GR deals with your specific interpretations and misinterpretations is illogical. Expecting GR to explain any more about time than it needs to is like demanding blood from a stone. Asking people to extract more information about time from GR is like repeatedly demanding to know the blood type of blood from a stone, and this is also illogical.

Keep in mind you've defined the problem as "not a logical problem", even though there is some intuitive logic in this example. If you generalize this problem then you're basically talking about making statements about a set based on a sampling of the set. When you make probabilistic statements based on samples (whether you take enough samples or, as the above example, not), you don't just have a probability that something is true, but you have a confidence interval or whatever. With your example, the "error bars" would be so big that the possibilities of the contradictory statements overlap or something. Also... treating this as a general example and not a real-world example, you allow the case that there are no crows at all. In this case, both statements about crows in the set are true. If you sample objects and none of them are crows (as you did in your example), you increase your confidence in this case being a reality. If you sampled all objects in the set and found that none of them were crows, you'd prove both statements with 100% certainty. If you sampled all but one object, and none were crows, the error bars on the probability of both statements would still cover various contradictory statements about crows in the set.