md65536

Disclaimer: I'm not a real physicist, and I haven't read all the replies, but I wanted to chip in a couple cents. First: How can you possibly see something that's frozen in time? In the first post, you admit that you can't, but then suppose that you can -- that's just asking for problems when you assume something that's known to be unreal. What exactly do you expect to see? If the clock is sending out a signal at frequency more than one million megahertz, yet it appears to be completely frozen for you, how much time do you think it will be between signals that you receive? Answer: Infinity much, that's how much. Similarly, if you are shining light on it and it is reflecting that light, then the light that it reflects in say a second of its own time would need to be stretched out into an infinite amount of your time. It would need to receive and reflect an infinite amount of light in its own frame, for you to see its reflection. Second: If you do not observe that the matter of the clock has been absorbed by the BH, then you won't see the same matter evaporate out of it (you'd never know it was the same matter but you could measure its mass to be assured that it is never observed evaporating more mass than it is observed to have). However, if the BH evaporates, eventually it won't be a BH any more (it will become a normal boring dense mass?), at which point you could see the clock fall into it. I think what you'd see is that as the BH evaporates, the event horizon shrinks???, and the clock is allowed to move closer and slowly forward through time as it follows the EH that is shrinking away from it??????

I suppose for me the biggest clue would be an answer to: Is "our" geometry the only one that works? If I am one unit of distance away from two other locations that are also one unit away from each other, that forms an equilateral triangle, with an angle of 60 degrees in "flat" geometry. Exactly 6 of these can fit around me in a circle. Why exactly 6? In curved space it could be 4, or some other number... could that curved space be transformed into a flat geometry and have everything work, only with a different value for pi, etc? Then if you could say derive pi from c without using any of Euclid's axioms or postulates, or express geometry in terms of entropy or something, then I think you could show that geometry is the way we perceive it because of some fundamental universal constants, and not due to the fundamental nature of our particular geometry. In other words if geometry is shown to be subjectively determined by universal constants, that would answer the question, no? Another way might be to find a way to deduce Euclid's postulates from physics. I need to go back to school!!! Edit: I suppose you would also need to show that the other direction (deducing fundamental universal constants from geometry) is not valid or something.

No, I don't think so. Do you mean that something moving along a geodesic changes direction? I don't think that's true either. The object might appear to curve from other viewpoints, because space itself is curved, but the geodesic is essentially a straight line in curved space. From the viewpoint of the object, the geodesic IS straight... it APPEARS always straight all along the geodesic. The object would not experience any acceleration. > they don't follow the same path as light because they curve more than light does. Light only orbits where escape velocity is C. I don't think this is a correct or meaningful way to describe it. "Orbiting" requires moving off of a geodesic (continuously, I suppose). > That seems as impossible to me as the possibility that light contains infinite energy and infinite speed (instantaneity). I don't see how that is the case. My theory would have to have that the predicted behavior of light is no different than our accepted predicted behavior of light. This is possible, because the singularities are inside particles, and "out of reach" of light. Light either misses the particle or is absorbed or redirected by the particle, but the light never reaches the singularity. This may in turn explain things like refraction, where to light, a "bumpy surface consisting of particles" can behave as a smooth flat surface to light which acts like a wave. Basically, the infinite spatial curvature would have an "infinite" effect only for a radius of 0. It would quickly fall off, on the scale of subatomic particles or something like that. It would not be allowed to cause any sort of inconsistency -- if it could then the theory is wrong. > I agree except in terms of negative gravitation. What's so implausible about repellant gravity, especially considering how electrons behave around the nucleus? Well, for negative gravitation, you'd have to have spacetime that curves in the opposite way from "normal", so that this "repellent source" causes length expansion and time speeding up. I don't know of anything that would be explained by this, or any reason to suggest it's possible, or any aspect of reality that seems related. It might also involve a paradox, such as "Spacetime that is flatter than perfectly flat." > And how exactly is that "precise location" determined then? I don't know, but experiments and observations and derivations and theories have calculated the size of various particles. Observations of mass and light and various interactions and measurements can determine where particles are. It's subject to the uncertainty principle, but I don't know if that relates to all this. > I had that with you since a few posts back:) We respond where we deem our response relevant enough to share, no? Yes, but I feel compelled to try to respond to all questions, even when my answers are just a guess! Much of what I'm saying is nonsense, I'm sure! lol The problem with integrating 1/r^2 at r=0 makes me feel like I've hit a wall with being able to reason about this topic. Sorry for the inline quotes... I got lazy.

No one would ever read or take seriously a book describing the origins of life by an eternal creative being with simplistic statements like that. The 7th D is a D of rest? No one would read something like that.

Force (such as gravity) on a mass results in acceleration. Net 0 gravity means no acceleration, but it still has its velocity independent of this (v can be 0 relative to other locations). Yes, a frame's acceleration provides a force equivalent to gravity, but not its momentum. Sure, but satellites are accelerated by gravity. If they weren't, they would fly off on their own inertia, and follow the path that light would: a geodesic that curves along spacetime. Yes, 1/r^2 describes the magnitude of gravity and other things as well, such as the density of a fixed amount of energy stretched across a spherical surface. The initial conjecture is that there's a mass density singularity in any mass. This suggests that the density would taper off to fill all of space, instead of having an abrupt edge between zero mass density and some finite mass density. I think a mass density singularity would imply a spacetime curvature singularity. It *might* be that the mass density and the spacetime curvature could be described using the same functions. Otherwise they'd have to be discussed separately. Yes, I think that infinite spacetime curvature could imply infinite force. That's 3 separate but highly related things (mass, curvature, force). Negative mass makes no sense to me. All I can say is that it probably has no relation to reality, but I don't know for sure. I'd rather avoid it, but if I couldn't avoid it, it might not destroy the theory (it probably would tho). I'm not actually making sense! I proposed a function with sin(x) in it because the integral of that is finite, but that's because sin(x) has periodically negative values. Sin(x)/x is a bad guess anyway, because the limit as x approaches 0 is not infinite, which is what I'd want for a singularity of infinite mass density. Sure does! Lengths, and time, depend on an observer's relative velocity and gravitational field. Quantum mechanics deals with observers differently depending on interpretation, with variations from "observing reality affects it" to "differently observable realities exist in superposition." Invariable aspects of reality don't depend on how it is observed. I equate that with "fundamental" aspects of the universe, with observer-dependent things being "emergent". Some aspects of geometry (eg. the curvature of space) are observer-dependent. I believe that all geometry is ultimately emergent. There are and may need to be different boundaries or fields for the different forces. Those would determine how it interacts with other matter or energy. I think that the precise location of mass-energy of a quantum of matter describes a boundary of mass (which may be different from interactions). You're going into topics that are beyond my knowledge or reasoning, though.

Wait a sec... I've been on crack this whole time. The infinite integral of 1/x is divergent. The infinite integral of 1/x^2 is convergent, EXCEPT for the singularity at x=0. So the "fall-off" of function f( r ) = 1/r^2 is fine... it doesn't imply an infinite mass, unless we allow r=0. Suddenly the singularity is not so convenient :/

I think spacetime can be flat at a point (or over a volume of points), iff at that point the gravitational pull from all mass balances out to a net force of 0. If the magnitude of gravitational force is directly related to curvature, then a gravitational gradient would involve the difference in curvature at different points, not the "steepness" of the curvature at those points. The main thing that affects tides is that the force of gravity from the moon at the point on Earth that is closest to the moon, is stronger from the force at the point on Earth farthest from the moon. This means a difference (gradient) in the curvature of space across the volume of the Earth. You could have uniformly curved spacetime (ie. be in a uniform gravitational field) and tides shouldn't happen, but that doesn't mean that spacetime there is flat. I don't think of gravity as an inherent force, but rather a kind of inertial motion in curved space. Geodesics are "paths of zero acceleration", so satellites do not follow geodesics as they're constantly being accelerated due to gravity (inward gravitation balances outward inertia in a perfect orbit). I'm speaking of any mass, specifically when viewed as a single indivisible unit (a particle, basically). I'm saying that its distribution isn't uniform, but that it is infinitely dense at a point in its center. This describes a singularity. Consider for example a spherical drop of water of radius R. Its mass distribution might be something like f( r ) = { 0, r > R 1, r < R This is a uniform distribution within its radius. A distribution like f( r ) = 1/r^2 has a singularity at its center, but unfortunately it describes infinite mass. So I'm not sure what type of distribution would fit what I'm proposing. (But, since I'm already babbling... I have thought about it: f( r ) = sin^2( r ) / r^2 would not be infinite (I think)... and it may capture a "wave nature" of matter... but unfortunately it has areas of negative mass-energy density which doesn't make sense to me, and it is not strictly decreasing which I assume matches reality. f( r ) = 1 / C^r for some constant C might work, but I don't see how this has any connection with observations and reality). No... I think that's already accepted by all(?) gravitational theories. I'm talking about the uniformity of the mass that cause these gravitational fields, not the field itself. Yes. 1/r (magnetism) and 1/r^2 (gravity) approach 0 as r approaches infinity, but they are non-zero for any finite r. They have no finite boundary, though far enough out they become negligible relative to nearer interstellar matter... or possibly even vacuum energy (dark energy?)) Yes, I think that as long as the objects didn't have inertia exceeding escape velocity, they should collapse. Yes, I suppose that's a good analogy. You could say that the boundary of the cloud is the volume in which all its water molecules are contained, but since the air around the cloud contains water molecules too, there's not a hard boundary. It's like a smooth transition between higher and lower humidity. You could define a precise boundary using some humidity limit. But like you said earlier, from far away a cloud may look like a solid thing (perhaps with uniform density), but as you move into it (as with fog), the boundary of the cloud appears to change with your location. This is what I think happens with masses or particles. I think the important things would be 1. It has to be consistent with all existing observations (subjective negligibility I suppose) 2. It has to be consistent with a sensible theoretical description (which might predict objective detectability) I think we're safe in the Speculations forum as long as we're speculating and not asserting claims! This conjecture wasn't meant as an explanation of gravity... to me it would only need to be consistent with existing gravitational theory. The effect of infinite spacetime curvature within a particle might be related to gravity but I personally wouldn't call it gravity because it might confuse things (nuclear force is similar in ways to gravity but different enough to avoid calling it gravity). Yeah... the issue of explaining volume of particles is key. I think the answer is that what we observe (of the subatomic world or the macroscopic world or anything), as far as volumes and empty space etc go, is not a fundamental aspect of the universe. Reality depends on how it is observed. That might open up some theoretical possibilities, but doesn't really help us figure out which are right :/ CRAZY IDEA: - The mass distribution of a point mass is 1/r^2 but it is scaled by some infinitesimal factor, such that the mass is only apparent where the density is infinite (at the location of the singularity, though I don't know how it would then appear to have volume). - This distribution represents "uniform mass density" throughout the entirety of a 2-dimensional universe... 1/r^2 means that a spherical shell of any radius would contain the same amount of mass as a shell of any other radius. If we remove a dimension or 2 (time and distance, specifically), we might be able to describe a 2-D geometry in which all 3-D spheres of different radii become identical structures in the 2-D world. In this case, the mass then is uniformly distributed across the entire 2-D universe. This is "nice" because it fits (vaguely) with the holographic principle, which among other things suggests that any point in a 3D volume maps to all points on a 2D holographic surface. This would allow a particle to be uniformly distributed across this surface. Question: Is it possible to modify f( r ) = 1/r^2 such that an infinite 3D volume integral becomes finite? Would the "infinitesimal factor" have to be non-constant? I will try to ask in a math forum...

I'm sure that gravity does cancel itself out as you suggest. At a Lagrange point between the the Earth and moon, the overlapping spacetime curvature due to the Earth (curving in one way) and the moon (curving in the other way) combine to result in flat spacetime. I don't think there's any distinction between "pure" and "net" gravitation: It's all net, whether you're describing a system with one atom, or a trillion stars. Yes, it's the opposite of a derivative. In this case, if you take the total mass energy of say a particle, then the derivative of that mass would represent the density of mass across space -- a mass distribution function. The integral of the mass distribution function would be the total sum of the mass. I may not be describing that with the right terminology. I'm not sure. However: We can make observations of mass and determine where that mass is. If I'm saying "that mass is actually spread out across all of space", that claim has to somehow match observed reality. One way to do that is the conjecture that any such "spread out" mass somehow appears as a particle: The spread out mass appears to be only in one not-spread-out place. Another way is if the mass density falls off at such an extreme rate that any mass energy outside of some distinct boundary is undetectable and unobservable and negligible, and thus all the mass appears to be within that hard boundary. Edit: I think the first option is true. I think that the mass distribution of a mass depends on how it is observed. For example, from far enough a way, a table should appear to have a uniform mass density, no matter how it is measured. From closer up (or on a smaller scale), that uniform mass will separate into particles, each of which appear to have uniform mass density. If you get smaller/closer then the particles can be broken up into smaller particles. I suppose at some point there is a quantum limit to this. However, I suspect that any apparent uniform mass density that appears from any of these points of reference is not fundamental; it is only an observational side-effect. Exactly... If we allow tiny singularities of infinite spacetime curvature inside any particle, then we may be able to model reality such that the singularities "average out" to form fairly flat spacetime on a large scale (effecting gravity), but have much stronger effects on very small scale (effecting EM and/or nuclear forces). If we assume that spacetime curvature is actually smooth, then there's no way that I know of to make the same curvature "weak" enough to explain gravity, and "strong" enough to explain the other forces, and still maintain a gentle curvature for small masses.

Tides are caused by gravitational gradient, not magnitude (the sun's gravitational pull is stronger but the moon's gradient is steeper due to it being closer and thus the moon's effect on tides is greater). Gravitational fields intersect or overlap. The gravitational pull of the sun and moon and Earth summed together would be the same as summing the gravitational pull of all of the particles that make up the 3 bodies. This is similar to the above idea that any mass can be considered a particle, from the right viewpoint. From some locations, Earth's gravitational pull is identical to treating Earth as a point mass (right?). I think that from the right locations, all physical aspects of Earth can be made indistinguishable from a point particle with the right properties. The meaning of "on earth" or "on the moon" is semantics. I don't think it needs to be defined to precisely describe gravity. However, it does bring up a good point: We know and can measure that gravitational fields intersect, but there is no evidence that mass or energy overlaps the same way. In fact it most certainly doesn't. The mass-energy distribution of a mass probably could not be 1/r or 1/r^2 because the integral of those over all of space is infinite. Unless we attribute vacuum energy or dark matter to this theory (which wouldn't work anyway cuz neither of those are infinite), we would probably require that the total mass is finite and in fact it should be equal to existing mass measurements of whatever mass we're considering. So the speculative "influence over area" of mass energy does not have the same drop-off function as the space-time curvature drop-off function of a mass. (Does that make sense?) So this idea certainly doesn't magically unify the forces. Mass energy and the spacetime curvature due to said mass would need different distributions. Why would that be? The distribution of the mass of a particle would have to drop off at a high enough rate that we could consistently observe that all the mass appears to be within a fixed boundary, in all observations in all of our history (whether it be planets or tables or particle experiments). UNLESS... I'm confusing a gravitational force function (proportional to 1/r^2) with a spacetime curvature function (which I have no understanding of). Googling it, I see that "space is nearly flat for weak gravitational fields". My conjecture is that this is not true, for a very small volume within any mass: At this point, spacetime is infinitely curved. Is it possible to "pinch" spacetime in a very small volume, such that: 1. It is infinitely curved at many points (wherever there is a mass particle), but 2. On average it is "nearly flat". On average, the curvature is exactly as GR predicts. ??? I think that eventually, physics will explain all of geometry, and will also transcend it and explain things that are "more fundamental" than geometry. Isn't this already partly true? Can (some) thermodynamic systems be described without geometry? Or the holographic principle? I think it would make sense if singularities exist in the geometry of space (just like they do in math), but only in the geometry and are "cured" in a topological description of the universe. Is the quantum description of electrons a geometrical one? I suppose it would also make sense if singularities disappear from the geometry with a new or more sophisticated description (this is really all over my head; I don't know what I'm saying). But... I think that singularities in the geometry are too convenient a thing to assume they're not really there.

Well, there's all sorts of abstract mathematics that can be used to describe real and unreal things. Singularities are simple things in math but they don't make sense given an assumption of a fundamental continuous geometry of the universe. However, if you explore some ideas that hint that geometry is not fundamental, then you can ignore geometry for awhile and imagine other things. For example, topology can be used without requiring geometry. It is still math. If we assume that geometry is fundamental and any mathematical description of the universe must fit within that geometry, then singularities are a problem. If we assume that geometry emerges from some other fundamental description of the universe, then whatever is consistent might be possible. Singularities might be a convenient means for simple consistency, and thus might be common. I think math is necessary because without it, we must use other conceptual tools such as language and spatial reasoning, and I think we would then limit our understanding to what we've seen or experienced. Is it possible to figure out a universe that may exist fundamentally "underneath" 3- or 4-D geometry, using spatial reasoning that's based on that geometry? So yes, I suppose if you remove the mathematical/geometrical restrictions that says a table can't intersect a chair etc, you can work with more abstract ideas... but we have to be careful about what we claim because words like "inside" may only have a precise definition with respect to a given geometric representation. I would think that studying topology would be the best way to precisely contemplate junk abstractly without being confined to our habit of thinking geometrically???

Way over my head but I'll have to research those topics if I ever try to develop the theory, thanks. A smooth manifold would have no singularities? So it all works without them, and may not (or may) work with them? This might mean that there are no abrupt edges to matter. The matter at a table's edge doesn't end there but carries on to exist (in a superficial form) through all of space. The hard edge that we experience might be similar in some way to an event horizon, dividing the matter into a volume where light and other matter interact with it, and a volume where they don't. The physical presence of matter would coincide with its effect on spacetime curvature. There wouldn't need to be a distinction between things like "The matter is over here but it curves spacetime way over there." Any matter would "fill" the curvature that it causes to spacetime. Just as a single molecule has a tiny but calculable gravitational effect in a location a light year away, that molecule's tiny speculative energy density should be calculable at the same location. This might relate to the aspect of the holographic principle that all matter in a volume maps to all points on a holographic surface. Basically: Any matter would exist everywhere at once, but it is only fully "experienced" at a small location where its concentration becomes infinite. All matter existing everywhere at once is also compatible with the idea that the universe can be fundamentally described as a singularity, with time and space being emergent observational effects.

I think I figured out the answer: The symmetry of this scenario is only observed by Earth (or anyone who remains equidistant to both twins). The symmetry is observed as the twins always remaining the same age and acting in synchronization. Other observers (such as the traveling twins) would not observe the scenario occurring with synchronization, due to "lack of simultaneity", so the twins can get out of sync (different age) with each other, before eventually returning to synchronization. For an observer to synchronize the twins' age, they'd have to become equidistant to each twin, which for the twins themselves can only occur when they're at the same place. (In general they would need to be not just equidistant but also have the same relative velocity to each???, which in this case is provided by the symmetrical motion of the twins.)

I remember hearing about maybe a Native American or South American tribe that believed that reality is a dream, and that our dreams are an actual reality... or something. I recently watched a Werner Herzog movie called Where the Green Ants Dream, involving indigenous Australians who believe that dreams influence reality or mix with it. To have children, they first have to dream of them. The dreams of certain animals affect nature and human existence, etc. Personally I believe that most of what we consider to be reality is emergent, but I don't think it has anything to do with dreams, other than what we use to perceive reality is capable of "generating its own sensory data sets" let's say.

Proving something about something unknown by assuming that it is only something that is known, is not really useful. This leads to conclusions like "heavier-than-air aircraft are impossible" and "rockets couldn't work in a vacuum". I could assume that all transmission of speech is carried by sound waves and go on to prove that telephones are impossible. You'd have to devise a test that would prove your abilities and rule out deception. Or, submit to the tests Randi would have already devised (which might be restrictively specific to some feat that he considers to be "telepathy"). If you have such tests or experiments it would be interesting to hear about them here, though ruling out deception would be difficult.

That is impossible. It violates conservation of disappointment laws. Otherwise, you could extract disappointment, and use it to power some kind of machine...? I'll admit to being frustrated by the speculations forum, too. There just aren't really a lot of people looking for new (and crazy or underdeveloped) ideas to explore and discuss. Those looking for real science in a speculations forum probably don't have the understanding of science needed to do serious collaboration. Those with the understanding already have enough well-developed ideas to think about, and will tend to see what's wrong with your ideas quickly, while anything truly new and valuable could take a lifetime of effort to understand and develop further. You're not going to find collaborators here. Scienceforums.net doesn't pretend that Speculations is really about science, as some of us do. The value in the speculations forum is in asking about a crazy idea that can be explained fairly easily by others, and in giving us pseudoscientists some space for self-indulgence with our ideas. Has there ever been a thread here that contained NEW ideas that were USEFUL, with a discussion that actually helped DEVELOP the idea?

After more thought on black hole singularities being coordinate singularities (or if I'm using the term wrong, rather: singularities that disappear depending on where you view them from), I figure that the solution that makes the most sense is that, uh... Say you're outside a black hole and that most of its mass is in the singularity, but not all of it is. As you pass the event horizon and approach the singularity, suppose that rather than the singularity disappearing, that more and more of its mass appears as "normal matter" outside the singularity, which itself becomes less massive. You could approach it "forever" as it expands spatially the closer you are to it, and more of its mass would expand out of it until you realize that you're surrounded by a universe that came from the "shrinking" singularity that you're still chasing. In order for that to be possible, the mass distribution of a black hole cannot be uniform or homogeneous or whatever. There would not be a hard boundary between outside and inside it (other than the event horizon, which is a precise boundary but there is no physical wall of matter or energy there). It would be distributed along something that looks like f( r ) = 1/r or 1/r2, with the density at 0 undefined (representing the singularity), and the density approaching infinity as r approaches 0. Extrapolating this idea from black holes to all matter, we get the following conjecture: - All mass is non-homogeneous in terms of energy or mass distribution. - All mass has a singularity at its center. Basically this would mean that the concentration of any distinct quantity of mass is greatest at its center, and tapers off to blend seamlessly into the surrounding nothingness, rather than there being a distinct boundary between mass and surrounding space. Depending on how you look at the mass, it could be that it has no size and 100% of its mass is contained in a singularity, or half of its mass is, or just a tiny fraction of its mass is contained in the singularity, yet that still represents infinite density for that small mass. We can extrapolate further and imagine that any mass can be described as a distinct unit in the same way. On the smallest scale, all particles could be viewed as individual masses with individual singularities. On a larger scale: If you were far enough away or warped space in the right way, all of Earth could be viewed as a combined mass with most of its matter contained in one singularity at its center. If you were outside the universe, most of it would be in one singularity, with some of its mass outside the singularity (and each particle of that outside mass containing its own singularity). Then since we're speculating without restraint anyway, why not conjecture that all fundamental forces are due to non-homogeneity of geometry, IE. curvature of spacetime. Just as large-scale curvature effects gravity, small-scale curvature may effect electromagnetism and/or nuclear force. Thrown in there is the idea that any mass might be described as a particle, depending on how and from where you viewed it. Thus, particles might be defined as an observer-defined quantization of matter into individual indivisible components. Then, just as a universe might be fully contained in a singularity, or might "spill out" into something with size (eg. a black hole) and divisible mass, so too might an elementary particle be a singularity or a divisible mass, depending on how it is viewed. A simplification of this idea might be: - All mass results in space-time curvature (already accepted with general relativity?) - The point of maximum curvature of any curve in spacetime is always a singularity. (There are no "gentle bumps" in spacetime.) Any related or contradictory ideas or evidence? Thanks.

No, twin A would not see anybody jump forward in time. I used to think that too... see this thread: http://www.sciencefo...post__p__569630 Twin A would see B's and Earth's time appearing to run faster at some point. It would calculate that their times are running slower. What I mean is, suppose everybody was broadcasting a timing signal every second. As twin A approaches Earth, she is moving toward each subsequent signal from Earth and "observes" them at a rate greater than one per second. Supposing A could turn around instantly, on the return trip she would see Earth time appearing to run fast (call it an illusion if you must), including the 2 additional years that Earth ages -- this will be seen by A. A will see B continue on an outbound journey for some time, during which A and B will be traveling in the same direction at the same speed, thus A will receive signals from B at a "normal" rate of 1 per second. -- Is this correct? Then at some point in A's return journey, she will see B turn around, and will receive signals from B at a rate higher than 1 per second (and also higher than the rate from Earth) -- even though B's clock is ticking slower than Earth's which is slower than A's according to A. I'm not interested in the "actual time" at B or at Earth, I'm only interested in the appearance of time passing as observed from different perspectives. The "apparent time" is consistent with "actual time" according to the travel speed of light (or any observation) at c. If I can't describe any situation in terms of what an observer will actually see, then my understanding of relativity is not sufficient for the work I'm doing.

I mean gamma = 2... I had the reciprocal. Other than that is my post correct? Or it doesn't make enough sense??? Obviously I don't do the math enough, but would a Minkowski diagram show the symmetry as it is observed by the twins or by Earth? Or does no one do relativity calculations based on what is seen vs what is calculated?

Suppose both twins A and B leave Earth in opposite directions and each travel for one year (rocket time) with gamma = 0.5 (relative to Earth), then return at the same speed. My understanding of relativity is that they'll both return to find the earth aged 4 years while they've each aged 2. They remain the same age. But I can't figure this out in terms of what they'd each observe. Twin A would see Earth time appear to run slow as she retreated from it, and then appear to run fast as she approached. Would she not also see the same thing happening to Twin B? Twin B would appear to age slowly (slower than Earth) on the outbound trip, and then appear to age fast (faster than Earth) on the return trip. However, I realize that to Twin A, her own outbound trip would appear to take 1 year, and the return trip would appear to take 1 year... yet to Twin A, B's outbound trip would appear to take more than 1 year, and the return trip much less. This is basically because when A reaches her farthest point, she is 2*0.866 light years rest distance from B's farthest point, so she won't see B reach that point for some time (as the light from such an observation will take time to reach Twin A). Have I just answered my own question? Yes, Twin A will see Twin B appear to be aging at a much faster pace than it will see Earth aging, but only for a fraction of the time? I trust that it'll work out to A and B aging exactly the same amount, calculated from anyone's perspective.

This is amazing. I don't know what to make of it. Do you think Verlinde was talking about images and the sounds of words in his paper? Or do you think it is the key to understanding his work, which he perhaps failed to grasp? Do you think that this really has any relation to an actual physical reality or to our understanding of it? If so, how could you demonstrate its physical reality, or what test could disprove it? So far all I got out of this is "Some things resemble other things (in shape and/or word sound)". To me, this is completely explainable in terms of how the brain interprets shapes and images, the development of languages, and the statistics of coincidence. None of these need to have any relation to a holographic nature of the universe. For over half a year I've resigned to labeling myself a crackpot, but I will stop now. I don't have nearly enough imagination for it. I'm way out of that league. But I see a familiar attempt to put complex ideas into simpler understood ones, which leads to analogies that may seem silly at first but can lead to better understanding after a lot of analysis. I think you have a lot of work to do before this will come near to any useful conclusions, and that you will completely change your understanding of all of these topics several times before that happens. Are you prepared to throw away all of this work several times over in order to truly understand it? If not, I fail to see any useful conclusion.

I recently read in Carl Sagan's Cosmos that some of Einstein's early thought experiments leading to special relativity involved imagining such collisions. See: http://www.american-buddha.com/journeys.space.time.htm and search for "cart" to skip to the relavent bit. The paradoxes and impossible situations happen only without special relativity.

I don't know what all this is but it's not science. The holographic principle is about science. You're taking it very far out of context, ignoring the science, and applying thick layers of interpretation (I suppose we all do that to some degree and must allow for it among us amateur scientists in a speculations forum). But I don't think your ideas have any correlation with the holographic principle that you mention in your original post. Misapplying other theories to your own probably does little more than confuse yourself and others. Admittedly I am guilty of it too. I don't plan to read through all of your posts but I think I've seen enough to say that the holographic principle does not back up your claims.

I know nothing but I feel like babbling. First, I don't think it's advisable to imagine a physical hologram. To do so, you will be imagining a specific 2D surface within a 3D geometrical space. It defeats the purpose of considering 3D geometry as emergent if you're picturing it in terms of 3D geometry. Instead of imagining a physical hologram, just consider its properties independently of a physical manifestation. Here are 2 properties of holograms: 1. All the 3-dimensional information is encoded in a 2-dimensional surface. What this means is that all the information you can stuff into a 3-dimensional volume, can also fit on some related surface (usually the surface is a sphere around a volume, I think). 2. Each point on a hologram's surface encodes information from all over the volume. If you consider a physical hologram for a moment, think about looking at a single point on it while moving your head all around. That single point will show what all sorts of different parts of the 3d image look like, depending on your point of view. That means that information from all over the 3d model being represented, is encoded into each point on the hologram. What this means is that rather than having a single point in the 3D volume map to a single point on the 2D surface and vice-versa, you have all points in the volume mapping to all points on the surface and vice-versa. This next part is speculative: Suppose you could encode all information in the universe on a 2D surface. Also suppose that different observational perspectives could observe a consistent view of that universe. As with a physical hologram, different points of view observing this 2-dimensional surface will observe something that is consistent with the specific 3-dimensional image represented by the hologram. The hologram is 2D but a 3D image with 3D geometry is emergent. If the universe is similar, then 3D geometry can emerge from the way information is arranged in a 2D universe. A hologram or holographic universe can be 2D but look consistently 3D.

I think it's right. My own conjectures lead to a similar idea... I posted about it in Speculations in the past week or so, but I don't have the math or the vocabulary to express the idea as precisely or sensibly. Thanks for the link to the paper. It should help me a lot. "Many physicists believe that ... space-time geometry [is] emergent." I believe this is the way to express an idea I've used in all my speculative posts, recently. I definitely agree with what I've read (skimmed) in the paper.

Corollary: If the apparent radius of a volume of space is determined by entropy, then the size of the universe could be determined by entropy. The fact that the universe is expanding might be due to the way that entropy is increasing. The fact that the expansion is accelerating, would have something to do with entropy increasing above some "nominal" rate. As a vague guess: Normal energy interactions would increase entropy at a "normal" fixed rate, while the splitting of particles or energy would increase that rate to a new higher but also fixed rate. More particles may mean more opportunities for energy to split further, increasing not only the rate of change of entropy, but the rate at which the rate of change of entropy is changing.