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md65536

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Posts posted by md65536

  1. 1. the inside part of the box (the content) is always smaller than the outside.

    I don't think this is true when relativity comes into play. Specifically I think that the inside of a black hole is "bigger" than the outside.

     

     

    But regarding the original question...

     

    Here are some concepts that I think are interesting when trying to understand infinity:

    - Infinity is not a value (infinity + 1 etc). If you treat it as a value, I think it's possible to say that infinity^2 == infinity. Google "infinite hotel" for seeing how you can expand an infinite value and not change its value. Or whatever.

    - There's a difference between countably infinite and uncountably infinite. The real numbers are uncountable but the rational numbers are countable (to my great surprise when I learned it). When speaking of infinite variability (such as the idea of multiple universes for every possible reality) the pigeonhole principle is also interesting. Example puzzle: If you have an infinite long string of digits that never repeats, will you eventually find any given finite string of digits within it?

    - An infinite number of things does not necessarily need to take up an infinite amount of space. Consider the infinite sum 1/20 + 1/21 + 1/22 + 1/23 + ... = 2. An infinite sum of positive numbers can be finite and in fact quite small. So an infinite number of monkeys could fit in a small room if the first monkey was normal sized and each next monkey was half the size of the previous monkey.

     

    Ask, or just google, for more info on the concepts. Probably the most fun way to understand infinity is to work through the puzzles and paradoxes involved, and build up not just one universal understanding of "infinity", but a whole set of tools for rationalizing about infinite values or quantities.

     

     

     

     

     

  2. What branch of science satisfies all of these criteria?

     

    Chemistry is not a science because we've never directly observed parts of one atom interacting with parts of another.

    Sure, you put baking soda and vinegar together and you get school project lava, but there's no evidence that the baking soda and vinegar turned into lava because we can't see into atoms as they interact.

     

     

    What is the next step? Prove that science is not science?

  3. Well according to thermodynamics, everything will eventually just become entropy, and then that's it. Perhaps everything will first get devoured by black holes, or most of everything, and then if Stephen Hawking is right, those black holes will "evaporate", leaving behind only entropy.

    Is black hole evaporation equivalent to heat death?

     

    I'm stuck on the idea that a black hole and a "universe seen from the outside" are essentially the same thing.

  4. I don't get why it would take so long to find the center of the universe. All they would have to do is find the *direction* that galaxies are moving, and then move everything in the opposite of that direction until all the galaxies or directions intersect at the same point. Just like when you inflate a beach and its surface gets big from a point in the center, so can it deflate.

     

     

    Around 9:30 to 11:06 in the video is a good demonstration of how an expanding universe would make different locations seem "like the center".

     

    If you inflate a beach ball and you know exactly where its surface is then you can find the center. We don't know where the surface (or edge) of the universe is, or what its shape is.

  5. ...But thats the normal way of thinking...It does make sense...how can simply having mass effect space-time...DOES NOT COMPUTE...

    My problem is why does mass curve space-time. Then I thought about gravitons. Then I thought: Perhaps they are inside quarks or something as they have gravity. If gravitons generate gravity how can space-time curvature be the cause of gravity?...So I thought of this as I couldn't think of any other why that could be.*

     

    There are plenty who could help...it's just that nobody except you and Mr Skeptic has ever actually posted here.

    From the way I see it: Quarks have gravity therefore they must curve space-time. This means atoms curve space-time.

    Personally I think that trying to reason past "quarks have gravity" is like trying to figure out what is beyond the edge of a flat earth. You can imagine anything you like as an answer, but if you skip way past the edge of your knowledge or understanding, then there's nothing real and known to compare against, to use to evaluate new ideas.

    Personally I don't think that gravity is a "thing" that can be "had".

     

    It is similar to inertia. You wouldn't say that things stay at rest because of particles called "nonmovitons" that are like little monsters that pin stuff down to the rubber sheet of space. Similarly I don't think you need gravitons to understand gravity. Gravitons might be real... perhaps any aspect of reality that can be measured over a volume can be described in terms of particles (perhaps not).

     

    So this leads to a suggestion for another way to develop your ideas. Break them down into smaller ideas, and work backward instead of forward, trying to understand the ideas that you are building on. Wikipedia is fairly good for that. If it talks about something you don't understand, it will likely link to it, and you can keep working backwards until you have enough of the fundamentals figured out. You can skip over as much as you want (math or stuff that's too hard to understand) but the less you skip the more you'll understand it.

     

    I also think that it's good to simultaneously accept that everything that has been discovered so far might be right, AND that everything that doesn't fully make sense might be wrong. That way you can work with new ideas using existing ideas that many others have put a lot of work into, but you can also keep your mind open to completely new ideas. It lets you not get stuck thinking that any one idea (existing or new) is the only solution.

     

    And didn't say anything about matter refracting through space-time. Its is simply an effect similar to refraction. And that is the idea I dis-like most.

     

    Thank-you.

     

    *You said yourself..."I am currently technically a crackpot!"...Instead of trying to help me with my idea, as none of us know how possibly to try to improve it, how about you try to find your own idea of why space-time is curved by mass. I would be interested in hearing your idea and it may perhaps help me.

    Well let's see...

    • I don't think that space-time is a thing or stuff, either. The grids you and others draw in spacetime diagrams are just measurements.
    • Space might be described as a measurement of length. Spacetime curvature refers to things like length contraction and time dilation. Space then can be said to be a measurement of the size of matter and of the emptiness between parts of matter. That is... the curvature of space affects the observed size of objects within that space uniformly (scaling matter and the space between matter equally).
    • Matter is equivalent to energy, and it is also "mostly empty space". It might be that energy doesn't really have a "size", and that a scaling of matter is equivalent to a scaling of the emptiness between quantities of energy that make up that matter. So, space curvature is a scaling of all distances between energy within that space.
    • Mass then is quantities of energy. The "force of gravity" and the spacetime curvature from which it is effected, is a measurement of energy densities or something.
    • ??? goes here.
    • Matter is made up of oscillating energy. As this energy oscillates it follows the same curvature that light follows, which makes it accelerate towards the mass that has curved its space. Light appears to curve because it is following the shortest path through spacetime, which isn't a straight line from our observational reference frame. In a sense matter being affected by gravity could be said to do the same thing. As it oscillates, the curved path toward the mass is slightly shorter than staying put or moving away from the mass. It might be that the object is becoming slightly smaller as it accelerates into spacetime that is curved more by mass. The opposite (growing bigger; moving away from gravitational mass) would mean the oscillating energy is moving farther on each oscillation, and it would require added energy to do so.

    Okay so this is crackpot speculation, by the way. Just rambling, confusing ideas. It's all beyond my understanding.

     

    The missing ??? part is beyond my reasoning. For some reason, the presence of energy in one place, affects the measurements of length in distant locations all around it.

     

    Does any of that suggest something worth exploring further?

  6. Well you could help me think of what the effects of gravity pulling on space-time would be.

    I don't see it that way. Rather, I think that mass defines the curvature of space-time, and that oscillating energy behaves in curved space-time exactly as a stationary object (or oscillating energy that otherwise has no motion relative to some frame of reference) behaves in "flat" space-time.

     

    I believe that because gravity is classically understood as a "pulling" force, we try to describe it that way (pulling on space-time, or pulling on light, or whatever). But I think it can be explained without speaking of "pulling" at all. In your original post you speak of "gravity acting on spacetime". I think this may be a confusing notion. I would say that mass acts on or affects (or even effects) spacetime; gravity is the observed result.

     

    The real question for me (which I can't answer) is this: How or why does mass define the curvature of space-time? To try to answer your question, it seems to me that mass seems to expand or "puff up" space-time around mass energy, in a way that can't be seen. For example, in your image the squares of the grid have more area around the gravitational mass, but since there's no visible grid in space, we don't actually observe that.

     

    You may have to restate your ideas in a new way in a new thread... I fear I may have derailed your thread by mixing in my own ideas. My hope was to suggest ways forward where our ideas overlap. I have no further ideas for you at the moment. Is there anyone else who can help?

     

    Where our ideas conflict I'll have to stick to believing what I currently do, unless someone compels me to think about it differently. Your idea about light refraction doesn't conflict with any of my understanding, and is worth consideration. For me the question is: "Does 'matter' define a curvature of space-time that on one scale (atom-scale) explains refraction (and possibly other things like electromagnetic force or strong force) and on another scale (planet-scale) explains gravity?" My previous understanding of refraction is that it involves light being absorbed and re-emitted by matter, but now I wonder if it can be completely explained by space-time curvature on a very small scale.

     

    Good luck with discovering and refining more ideas!

  7. But not violating the speed of light is a problem when linking the galaxies together as the space between galaxies is expanding faster than that.

    Does it have to have a human time-scale? If not, why not accept the limit of c in the simplest way? If stars are tens of lightyears apart, then a single thought might take thousands of years. It would be like discovering a giant that is hidden in plain sight due to it being inconceivably large, and so slow that its movement is undetectable. In a human lifetime it would be like the brain is paused mid-thought. Humans might need to do some kind of computer simulation to discover "what thought is the galaxy currently thinking?" The buildup to an answer could be quite interesting!

     

    Where the space between "neurons" is growing too fast, this could represent "individuals" that are disconnected from each other and have independent thoughts.

     

    On the other scale, it might be discovered that tiny quantum fluctuations on such a small scale might represent the equivalent of billions of years. Perhaps in the brief flashes of an LHC collision, a universe is born, and it appears tiny only from the outside, yet inside it billions of years seem to pass, and galaxies form, and intelligences evolve and try to figure out the meaning of their universe... yet to us it all appears and disappears in a flash as their universe suffers heat death and becomes just a bug on the windshield of the collider detectors.

  8. And I don't know either. I didn't know GRT predicts that it travels a c. but I don't see how that is relevant.

    The relevance is that gravity in some way is similar to light.

    Special relativity is based on the invariance of c, meaning that from any reference frame, light travels at c. Neither moving relative to a light source, nor experiencing time dilation and/or length contraction, will change the observed speed of light.

    So I assume nothing will change the predicted observed speed of gravity waves.

    That's not the same as saying it's "unaffected by time", but I think it'd be possible to make some kind of argument like that, if you were careful with your wording and especially clear about what frames of reference you're speaking of. Frames always trip me up.

     

    1. and 2. were just attempts to apply the original idea to planets and their motion. If it's wrong then let someone else try to explain why mass = curved space-time = gravity.

    Why does it sound wrong?

    [My argument against that: General Relativity Theory sounded wrong when people first heard it.]

    Well, it sounds wrong in exactly the opposite way. GR sounded preposterous but the math said it was right. Your idea sounds reasonable (at least once GR is accepted), but I can't think of any math to support it.

     

     

    Note(s):

    Perhaps there is no time...Made time is the effect of increased space. [Things have more space to travel through giving the illusion of events passing more slowly and the illusion of time.] ...I'm still not sure if I support this note yet...

     

    ...You can bust holes in my idea if you want but please don't make them big holes...If my idea is a person. Use the piercing arrows before you start throwing sticky grenades. Preferable you could make it stronger first by suggesting ways that make it sound more right and less wrong...

    Well, within that analogy I'd say I can't see the person clearly enough to get a good shot with any weapon.

    How to strengthen it: More math. Expressing the ideas more precisely relative to existing accepted ideas.

     

    I also can't think of how to strengthen the ideas, but I could quickly go over my own theories or understanding of how it all works... (Disclaimer: I am currently technically a crackpot!)

    - Time is literally equivalent to distance and both are observational effects. I would say "there is no objective time or distance" rather than just "there is no time". I think the universe can be described consistently without time and distance (instead, with chronology and order, respectively). It might be described "non-observationally" as a singularity with topology but not geometry, while geometry is a product of observations of the universe.

     

    - The force of gravity falls off inversely proportional to r2, while the surface area of a sphere increases proportionally to r2. To me this means that the total force of gravity exerted by a mass can be "spread evenly" in a sphere around the mass and the total sum of that force will be the same at any distance r (it will just be spread thinner the farther out you go).

     

    Also note that the visible area of an object (the moon for example) is also inversely proportional to r2. This means that if the sun and the moon (which look roughly the same size) were discs of the same depth and density, they would have the same gravitational pull on us. As it is, the sun is much less dense but much much much "deeper", and so has a much stronger gravitational attraction. -- I don't think this has anything to do with how it works, I just think it's interesting.

     

    - Because geometry is an effect of observation, we can conceptualize warping space to make it look different from a different (possibly non-observational) point of view. For example you could imagine warping space so that all the possible spheres concentric with a gravitational mass actually have the same surface area. From that point of view, the force of gravity would be the same at any distance from the mass, but all matter and objects would get smaller the farther they are from the gravitational mass. This, by the way, is an example of a vague and underdeveloped idea!

     

    Imagine a mass such as a spherical black hole, and draw lines like rays from its center. From our point of view, we see the rays diverging as they extend farther away from the mass. You might imagine turning the black hole "inside out" such that the lines diverge the closer you get (and converge to a point approaching an infinite distance from the black hole, where its gravitational attraction approaches 0). This might be what a black hole "looks like" to light.

     

     

    On the off chance that any of that made sense, it still doesn't answer your question: Why would mass make space appear differently curved in different frames of reference? I don't know. I think though that length contraction is a necessary means of maintaining consistency of observations.

     

    - Finally, if we imagine all matter as oscillating energy (traveling at c), then we might say that nothing is ever really "at rest". If you imagine a particle as energy constantly moving back and forth, but while it's doing this each trip back and forth is curved slightly exactly as the path of light is curved due to gravity, it takes on a trajectory that accelerates toward the gravitational mass. Then, the "time" aspect of the particle's acceleration can be expressed in terms of the number of times it oscillates back and forth, or alternatively as the total distance it travels in all its oscillations.

     

     

    This is all speculation. I think it would take 10 years (possibly 100) to develop these ideas satisfactorily. I'm still working on the first one, and it's a lot of work and maybe 90% of my ideas so far turned out to be wrong (but the math really does shine a light on it all). Wikipedia says of Einstein: "In 1907, beginning with a simple thought experiment involving an observer in free fall, he embarked on what would be an eight-year search for a relativistic theory of gravity." So it might take some time, for any ideas by any of us!

     

    Sorry I can't be more directly helpful with your ideas.

  9. 1. Gravity [and other forces] may be free from the effects of time. This would mean as an object passing a high(er) gravity object would move slower because of the slower time but gravity still pulls at the same speed causing object 1 to move closer, causing a curved path. I have no equations and can't make any and don't have exact values etc. but if it is wrong it will show up in the numbers...

    Well, to be honest I skipped over idea 1 because I don't understand it. After reading it quite a few times, I think what you're saying is...

     

    Ignoring time, the gravitational force of a mass is the same everywhere.

    For example, the sun's pull on Mercury is the same as the sun's pull on Earth, except that since Mercury is experiencing slower time, and since gravity is not affected by time, it accelerates toward the sun faster. Using gravitons just for the sake of analogy, one might say that Earth and Mercury are receiving gravitons at a time-independent "universal rate", which in Mercury's slower time it appears as if more gravitons are received per unit of time.

     

    Is that what you're saying?

     

    As for the math... the force of gravity is inversely proportional to the square of the distance between 2 masses, so to simplify things imagine something at say Earth's orbital distance from the sun. Another object twice that distance will experience 1/4 of the gravitational force. However, they will experience very little difference in gravitational time dilation. I can't think of any way to explain the difference in force as an effect of time dilation.

     

    (Actually I think using Gm/r2 is a Newtonian approximation that ignores relativistic effects, but if you can predict the orbits of planets while ignoring relativistic effects then I think it's unlikely that relativistic effects like time dilation can fully account for the orbits on their own.)

     

     

    As for saying that gravity may be free from the effects of time...

    General relativity predicts gravity waves that travel at c.

    I assume these waves would obey the same relativistic laws as light, and so "the speed of gravity" would not be affected by a mass's relative velocity.

    So in some sense gravity is time independent........... unfortunately the meaning and possible significance of this is whooshing over my head.

     

     

    Anyway just cuz I don't get it doesn't mean it's wrong. Also... it sounds wrong!, tongue.gif but even it if is that doesn't mean it can't be corrected and remain an important and good idea. For example instead of explaining the motion of the planets, it might explain the just the difference between Newtonian and General relativity's predictions of orbital motion... I dunno!

  10. 2. Light refracts when it hits a different higher density medium to the one it was travelling through. Space-time could act like a medium for matter [and energy?] causing it to change direct. As space-time doesn't get suddenly 'denser' and only progressively increases in 'density' object 1 would progressively change direction as it passed object 2.

    I like this idea and it's intriguing. I think it needs much more development though; how is space-time like a medium? How are the two alike, to make refraction and gravitational lensing the same mechanism? Figuring out the math should show what's right or wrong about the idea, and open up a ton of new directions to explore. I'm not intrigued enough to try to do this myself.

     

    I'm pessimistic about the chances of non-scientists like us explaining their underdeveloped ideas and having scientists "get it" with the same intuition that you have that tells you it's an idea worth exploring. If you can, and if you care, keep working on your ideas and developing them as best you can. And keep writing about them! Even if you no one develops your ideas directly, perhaps someday someone will be working on related ideas and gain insights from yours. But... there are so many crackpots out there, that undeveloped ideas tend to be lost in a sea of crackpot theories, and no one has the time to read them all, think about them all, and separate the good ones from the bad.

     

    Also... it's usually easier to explain why a new idea is wrong (even if it's a good idea) than it is to explain why a new idea is right, so don't worry if people focus on that. A good idea can be modified until it's right.

  11. right, so i got some terminology mixed up, i though geodesic was actually the shape of spacetime or soemthing.

     

    theres a reason i didn't study relativity.

    I'm (still) not a physicist, so take this with salt:

     

    A geodesic is the shortest path between 2 given points in curved space. In Euclidean geometry, a geodesic is a straight line.

    With curved spacetime, the shortest distance is not always a straight line. In fact, geodesics will appear to have different curvature, depending on the observer.

    I have a feeling that if you were to travel along the path of light as it curved through a strong gravitational field, it would appear to you that you were always following a straight line (though you would see space warping around you as you change between weak and strong gravitational fields), while an observer in a weaker field would see you travel a curved path.

     

    Using the rubber sheet analogy, imagine that from your perspective you always see the rubber sheet as flat, even though someone else might describe it being deformed by a large mass pulling it into a "bump". The shortest path would not be straight over the bump, but would be to go around it somewhat, with a curvature that depends on how deep the bump is. With a typical bump, you would never see the shortest path across the bump being a full circle. For a really steep bump, the limit would probably be a semi circle.

     

    So, mass does not pull light or the "lines of space" into it the way that gravity pulls matter. It curves space, the way pushing into a rubber sheet might.

     

     

    Suppose you want to describe a geodesic from point A to point B, that is nearly a full circle, around a planet or a black hole or something. What you are describing is that the shortest path between A and B goes all the way around the circle. So it must be no longer than the straight line distance between A and B. To do this, you would need to stretch the space that exists between A and B into a circle.

     

    Or another example: Suppose you are describing some gravitational phenomenon that allows you to shine a flashlight in your hand towards some planet-sized blackhole-like object, and have the light curve along a geodesic around the object that brings it back to your eye. Then the geodesic from flashlight to eye describes the shortest path between the two. This would only go "around the object" if you could take the spacetime between your flashlight and eye, and pull on it and wrap it around the object. If that were possible to observe, any observer that still saw the object as planet-sized would probably see your arm being at least planet-sized (most likely many many times larger).

     

     

    I didn't quite express what I intended to there, at least not very clearly.

     

    Another analogy might be if you imagine placing a ruler along a geodesic.

    If you travel along the ruler it will appear to be straight.

    If the ruler is 1m long and straight according to one observer, yet another observer sees the same geodesic as a planet-sized near-circle, then what they will see is the ruler and surrounding space stretched into a planet-sized circumference.

     

    I doubt this describes anything realistic, however I believe that warping of similar scale (or larger or even infinite?) occurs with black holes.

    To us, a black hole may seem like a small sphere. To light that cannot escape it, the same distances seem infinite.

     

    ---

     

    Must edit... since I totally went on a tangent from the original post.

     

    Yes, something horizontal on earth that we see as pretty flat appears flatter to us than it would be observed by a distant observer in weaker gravity (they would see it being slightly/unnoticeably curved).

    However, since the earth is sphere it's pretty much always going to be round. A distant observer will observe length contraction due to the curvature of space, so they would see the earth slightly/unnoticeably smaller than we would observe it. This is pretty much the same as saying it's less flat: a given surface area on a larger sphere is flatter than the same surface area on a smaller sphere.

  12. Thank-you...Now i'm pretty sure my thought is not general relativity...but if your explanation is true then where did that diagram come from? There doesn't seem to be a connection...

    Also where did people get: Time slows down near high gravity: from it? Either I don't understand or your not correct or...

    Here's an example of how you can visualize time slowing down, using the diagram.

     

    Imagine 2 trains traveling at the same speed on 2 different lines on the drawing, one which is curved more than the other. The train on the curved path will appear to take longer because on the drawing it has longer lines to travel along.

     

    However, these lines represent straight lines in space, so (assuming no acceleration of the trains due to gravity) the train on the "curved" path in the drawing would appear to be moving slower across the same distance as the other train.

     

     

    Similarly you can imagine a train spanning the long curve underneath that orange ball in the picture. Then picture that curve and the train mapped vertically onto a straight line, and it will be shorter than the curved train. This illustrates length contraction.

     

     

    Yes, this diagram is not perfect and probably only makes sense if you already understand some basics of GR. The picture doesn't teach GR. One problem is that the vertical dimension (time?) doesn't represent the same thing as the horizontal dimensions (space), so the diagram illustrates a concept, not a visual observation.

  13. So it would stay that same small size? The gravity of the entire black hole is not necessary to keep it that small?

    These are guesses based on a limited understanding of general relativity:

     

    It would not be observed to be the same size. Yes, the entire mass of a black hole keeps everything in it small, not just (or at all?) because it compresses matter against other matter, but because it curves space and length-contracts everything (the size of any matter and the empty space between it).

     

     

    Using the bag of sugar as a prototypical 1kg, let's just say that you're inside the black hole next to this bag of sugar, and then you and the sugar are transported to Earth. You would experience the same change in observed lengths as the bag of sugar, so from that point of view the size would not appear to change.

     

    How is it conceivable to be in a black hole next to a bag of sugar? If space is contracted so much that what we see as a "small" black hole has length contraction so severe that the bag of sugar and you are infinitesimally small, then the infinitesimal space between you and it can fit comfortably in the black hole along with rooms or planets or an entire universe, making it seem like the inside of the black hole is mostly empty space.

     

    The way to figure out what you'd expect to see is through math, and I don't know black hole math. I may be way off on what the math says, and I may be way off on the interpretation.

  14. If the rocket is at rest 4 light years from Earth and instantly accelerates so that gamma = 2, then without the rocket having to move anywhere yet, it is now 2 years away by light signal. So the Earth must have gone through 2 years of aging during that rocket-time.

    The earth will not instantly age. 2 earth years will not have passed until the moving twin gets two light pulses. The wikipedia part is right.

    Then I should change the wording... something like:

     

    So there must be 2 years of Earth aging corresponding to the contraction in distance between Earth and rocket, but the full 2 years of aging will only be observed over time as the rocket moves, and any yet-unobserved portion of that expected aging can disappear (or be wiped out by another simultaneity correction or something) if the rocket doesn't maintain its velocity.

  15. Solution 4. The amount of aging that manifests itself depends on the amount of travel prior to the frame switch, not the frame switch itself (the effects of which are often ignored, because they tend to be small). If we have one scenario where the moving twin ages X years and the earth twin ages Y, with only the acceleration at turnaround, we aren't going to change that if the moving twin undergoes other course-changing (but not speed changing) accelerations along the path. What will change is the rate of observed aging, (i.e how much happened, and when) but not the total amount. Changing speed will affect the amount of dilation that is observed, but that can be directly calculated.

     

     

    If the earthbound twin sends out a light pulse at regular intervals, there is nothing the other twin can do to make one pulse pass another, which is what would be required to have time going backwards.

    Suppose rocket twin is at rest 4 light years away and Earth twin is sending a pulse every year. You might have a situation where there are 4 pulses "en route" that till take respectively 4, 3, 2, and 1 years to reach rocket twin. Then suppose rocket twin accelerates toward Earth such that gamma = 2 for a negligible duration. The space "occupied" by the pulses contracts, so the pulses are now .5 light years apart, and will take 2, 1.5, 1, and 0.5 years to reach the rocket. If the rocket returns to rest the pulses will return to taking 4, 3, 2, 1 years to reach the rocket.

     

    Is this correct?

     

    I'd somehow assumed that invariance of c would mean that the light pulses would remain the same distance apart (oops) and that they'd be 2, 1, 0, and 0 years away (the last 2 compressed into a "burst" of aging the Earth appears to experience).

     

     

    If the rocket is at rest 4 light years from Earth and instantly accelerates so that gamma = 2, then without the rocket having to move anywhere yet, it is now 2 years away by light signal. So the Earth must have gone through 2 years of aging during that rocket-time. I'd (incorrectly I guess) assumed that the rocket would observe that aging during the instant acceleration. If I now understand correctly, we might say that the 2 years of aging applies to Earth's present ("now" on Earth according to the rocket is 2 years away whereas it was 4 years away only moments ago), which the rocket won't observe for some time. I see now why wikipedia says the frame switch is more of an update to simultaneity than a literal aging. If the rocket remains at that velocity (about 0.866c so that gamma = 2), then it will observe those 2 years of Earth's "extra" aging spread over some time as it makes its way back.

     

    Is this also correct?

     

     

    Further, if the rocket is 2 light years away and goes from gamma = 2 to gamma = 1, it is now 4 light years away, and the "update to simultaneity" means Earth's present (according to the rocket) is earlier than it was a moment ago, but no "negative time" will be observed because the rocket is no longer traveling. The expected observation that was less than 2 years away a moment ago is now 4 light years away.

     

    I will have to update my calculations and see what I can salvage from them. When I feel I understand some part of it, the twin paradox seems like the greatest math and logic puzzle I've ever attempted. The other 95% of the time it's the worst.

  16. Short version: Can a space traveler ever observe Earth time appearing to go backward? I claim "no" but under that claim I keep coming around to an inconsistency where more distant things will age more than nearer things. Where am I going wrong?

     

     

    Long version:

     

    I'm trying to figure out what is observed by the traveling twin during an extremely fast deceleration + return acceleration phase in the twin paradox. This is also described as the rocket undergoing a frame switch. According to my understanding of what I've read, the traveling twin will see the Earth twin age a large amount in that very short period of rocket time.

     

    What happens if the rocket "frame-switches" several times while far from Earth, by coming to a stop and accelerating toward Earth, then stopping and accelerating away from Earth again (involves multiple switches between 2 frames: outbound, and return)? What happens if it repeats this, "shaking" back and forth, reaching high velocity each time, over a very little duration of rocket time?

     

     

    Solution 1 (no good): My calculations show that the Earth twin will continue to age rapidly during these frame switches (specifically, she will age much as length contraction takes effect when accelerating in each direction, and age not at all as length contraction is released when decelerating). However, it also is apparent that the distance that the rocket is from Earth will determine how much the Earth twin ages when the rocket does this little trick. This leads to inconsistency...

     

    Suppose the rocket has traveled to Planet X which is stationary relative to Earth, and then "shakes" for awhile. The Earth twin will age a lot relative to the rocket twin, but a Planet X twin will age only slightly faster than the rocket twin. This makes no sense because the Earth twin and Planet X twin should not age differently relative to each other.

     

     

    Solution 2: When the rocket switches from outbound to return frame, the Earth twin will age relatively fast, but when switching from return to outbound frame, the aging difference will be undone. One way for this to happen is for one twin to age fast and then the other twin to age fast. But if the rocket can shake many times in a short period of time, it should age only that short period of time. So if the Earth twin ages a great amount during one frame switch, it must un-age on the other frame switch. This means the rocket can observe earth time going backwards.

     

    I hope that this is NOT the case, because it punches a huge hole in my theory of how time works, and my understanding of observable reality.

     

     

    Solution 3: The time periods in which the Earth twin seems to age greatly actually overlap, so that if the rocket shakes for awhile, the rocket twin observes only one aging period on Earth (possibly fluctuating between fast and slow aging as the rocket shakes?).

     

     

    Solution 4: Not all frame switches have the same observed relative aging?

     

     

    Solution 5: Something I've missed? Some way in which time dilation compensates? Or a maximum possible acceleration rate?

  17. I beg to submit an alternative physical theory, 'Hypothesis on MATTER' for critical comments from learned members. Given below is a list of few conclusions by the concept. At first glance, many of them may appear to be bizarre speculation. But I can assure the reader that these conclusions are derived by postulating only one type of real entity and developing the concept strictly on 'cause and effect' relationship from the postulated particle. Since the topics covered in the hypothesis are many, for the present, the concept uses no mathematical proofs or derivations. If the concept seems to be plausible, detailed study will be continued. If at least few members show interest, we shall discus the concept step by step.

    As a fellow quack I have some advice:

     

    1. People will tend not to be as interested in your ideas as you are. I've assumed that people will "get" the idea I'm trying to convey, and that they'll share my gut feeling that it's something interesting and important. For some weird reason, that just doesn't seem to happen. Perhaps if there was a compelling reason or evidence that encourages people to think about it, then... I dunno. Personally I haven't got anyone to work on my theories... I'll let you know if I do!

     

    2. The math is kind of important. You can figure out an entire theory without it, and it may make sense, but if the math doesn't work then the theory is probably wrong. What I've found is that a good theory will suggest what the math should be, and then the math will either work or it won't, or it will work unexpectedly, which in turn will tell you new things about the idea. It turns into a cycle, of ideas leading to math and math leading to ideas. If the math works, it can explain the idea much more clearly than without it. If the math doesn't work but the idea is good, the math might suggest how to fix it. The same goes for experimentation.

  18. 2. Perhaps there was no big bang at all, but we are on the other side of black hole, which formed 13,7 billion years ago from the stars it devoured?

    By "other side" do you mean "inside"?

     

    Check this video:

    Skip to a question at the end, around 57:33.

     

    Special relativity allows observed time and distance to be different for different observers. General relativity says [citation needed] that weird stuff... that interesting stuff... happens inside black holes. One observer can see certain distances expanded to infinite lengths, while another on the other side of an event horizon can see it contracted to infinitesimal lengths (I'm not sure about the math on this).

     

    As Krauss suggests, it is possible that from the inside, our universe looks like it does (expanding) AND from the outside it looks like a shrinking black hole. We could be on the inside of a black hole AND have had the big bang happen.

     

    We often think of what might be "outside our universe" as some alien observers on some unimaginably large scale looking at our tiny universe within theirs. Personally, I think that if that were possible, then from our point of view, that outer universe wouldn't be a huge thing, it would look tiny to us. I think it's possible (topologically) to have 2 universes inside each other. Suppose that some given black hole is another universe, and you could cross the event horizon intact. I think that what you would see is the black hole universe expanding on one side of you and our universe shrinking on the other side. The event horizon, imagined as a spherical surface on one side of you, would expand until, when you are at the event horizon, it is infinitely large and looks like a plane cutting through you, dividing the black hole universe on one side and our universe on the other, and then once you are past it, it would shrink on the other side of you, encompassing our universe, making it appear to shrink into a black hole. I've described this idea using a sweater as an analogy... the sweater can be turned inside out and have one side "inside" the other, without breaking the sweater. Crossing from one universe to another like this involves turning the universe inside out... not physically, but observationally.

     

    I don't know enough about general relativity and topology to tell you how realistic this idea is.

  19. Again I'm not saying your theory is wrong, just that it doesn't follow from everything that has gone before it. If speed = distance/time and you're saying that information is transmitted and recieved instantly (as your theory describes) then we will have to redifine all previous physics to fit your theory?

     

     

    Anywhere that I've contradicted special relativity, I've turned out to be wrong. I do have a new formulation of time, which fits with the existing definitions of distance and velocity and junk, so that the end result is that the speed of light (as defined by the existing definitions) remains finite. This new formulation can also be used to describe a "non-observational" model of the universe, in which light transmissions are instantaneous -- though I still don't know how one would describe time in that model.

     

    I think I'll again try to stop talking about the theory until it's ready to submit to a preprint archive. I'm having some trouble with the math unsure.gif

  20. Where is the future? Inside me.

    An interesting idea. Pretty much all I have to say about the future is that it can be predicted, but can't be observed. Would you connect in any way this "future inside me" with the mind's ability to predict the future?

     

    I don't see this with your theory of TDR. That's not to say it's wrong, in fact it could well be right but it seems to be out there on its own and not built upon existing understanding of physics. It may not exclude or contradict existing laws but doesn't necessarily require them either thus making them redundant (in terms of your theory) and then you have to ask why have a theory that doesn't require certain laws of physics which you do require to interpret the theory in an everday sense.

    The more I work on my theory, the more it appears to be exactly like special relativity (sometimes I even wonder if there's a difference). My current view of it is that Time Relativity provides a new definition of time that works perfectly with special relativity (SR). It doesn't replace relativity, just its definition of time. In fact, I might be able to sort of "slip it in before special relativity", and use it to explain some of the "existing understanding of physics" that SR is based on.

     

    I definitely don't know enough about the physics of everything connected with relativity. I haven't even considered "mass" (so I can't show E = mc2, kind of an important part of SR). All I can say is "I'm not aware of any contradiction between this theory and SR". I will also try to claim that time relativity corresponds to special relativity. Certainly, any prediction made by this theory that deviates from SR could potentially disprove it.

     

     

    Why have this theory?

    1. It explains a lot of relativity junk in an intuitive way (which I've yet to do...).

    2. It provides a better definition of time that might be immensely useful in quantum mechanics (this is yet to be seen).

     

     

  21. I'm working hard but sporadically on a new version of the paper, which fixes a lot of problems in the original. I'm trying to get it finished before Oct 5th, which as you all know is when they select the recipient for the nobel prize in physics. :D

     

    I'd like to thank those who've tried to "get" my theory, even though I haven't explained it well (I too am struggling to understand it). The new version, whenif it comes out, should be a great improvement in that.

     

     

    So far though, I'm not aware yet of anyone who seems to get it (or thinks it's important). Admittedly, what I've made available so far is full of errors.

     

    But anyway, here are a couple misconceptions I want to clear up:

     

     

    "If one location is in the past relative to another location, then from another point of view, some location can be considered to be in the future..."

    No no no, and as I said there's really no place for a concept of a "relative future" in this theory. No matter the observer, everything else is observed in the past.

    Another way to put this is that time is equivalent to distance. If the distance from A to B is 1 light-year, we don't say that the distance from B to A is -1 lightyear. If some location is relatively in your future, then you are a negative distance from it, which is nonsensical. The sign of neither time nor distance depends on direction.

     

    "It is the present in all locations, so if it's the year 2010 on earth and the year 2010 on a planet a light-year away then..."

    Different locations will have different clocks, and thus different calendars (which are basically large-unit clocks). Different locations can have clocks and calendars that pass at different rates depending on relative velocity. It is possible to synchronize calendars across distance, but it will be difficult to keep them in sync. If some remote planet keeps track of its time in Earth seconds and years, but "sees" Earth under time dilation, then one Earth-year may seem to take longer than a year; it will seem to take different amounts of time when it has different relative velocity.

    If A is set up so its clock matches the clock it observes at remote location B, then B will not see B's clock match what it sees at A. Speaking about it being 2010 on a distant planet means that you are using the clock at one location (Earth) to describe the clock at another location. To speak of "the present" at multiple locations, it is best not to confuse things by using one location's clock to describe the time at the other location.

  22. I also found it hard to believe that time slows down with motion when I first read about it. I suspect most everyone does. But we know from experiments with atomic clocks on airplanes, on rockets and in satellites that time does really slow down with relative motion. We also know this from the measured lifetimes of subatomic particles in our atmosphere and in particle accelerators. Yes, this so-called time dilation is crazy. Yes, it violates our common sense; but it's true! I like what the famous physicist Richard Feynman said (he said it about quantum theory, but I think it also applies to relativity): "Mother Nature doesn't care whether we believe it or not, this is how She works."

     

    And yes, this relative slowing of time due to motion implies time travel. In fact, we do it all the time! It's just such a tiny effect at every day speeds that we don't notice it.

    Ah jeez...

     

    I'm working on a theory (the original theory posted at the beginning of this thread, except that it's gone through about 8 major revisions, several times changing its meaning completely), that explains relativity. Or uh... it will... when I'm done...

     

    What I've found so far:

    - Relativity *does* make common sense, once we have a better understanding of time. There are simple thought experiments that show that any relative motion doesn't make sense without time dilation (even if it's unnoticeably small).

    - Relativity does *not* imply time travel (in the sense that you could travel to the past or future). ON ONE HAND, one could say that the simple passing of time (either at a normal rate or a modified rate) is time travel, but it's not *really*: whether you sit still and pass time, or move around differently relative to different locations, and thus pass time relative to those locations at different rates, no matter what you do, you will be in your present. Anywhere you go, you will be in that location's present. It can all be explained without using the word "future".

     

    Relativity is consistent. All observers will agree on the relative age of any two objects (twins or clocks or anything) that are in the same place. That means no one can observe you in one time relative to your location, while another observer sees you in another time relative to your location. No time travel.

     

    You *can* see weird time effects across a distance (loss of simultaneity, no common chronology, etc... IE you can be observed in different times relative to some location, by different observers), but you can't interact with distant locations without requiring the passing of time (there's not remote time travel or time-travel of information).

     

    Anyway you slice it, any event (interaction, transfer of information, etc) will have a single location and occur at a single time at that location.

     

    Time slows down with velocity not acceleration. If for instance A is travelling faster than B then A will experience time slower relative to B.

     

    But it seems like people are saying that A and B have relative velocity and therefore they both see the same time dilation in each other.

    Then A accelerates and whilst A accelerates it experiences time at a slower rate compared to B.

    Then, when A stops accelerating and returns to uniform, albeit greater, speed, there is relative velocity between A and B again

    A and B see the same time dilation in each other again but both see A is now a little behind B.

     

    Is that what people are saying? If so they are mistaken.

     

     

    Well, it sounds mostly true except that last line. They may only "both see the same thing" when they are brought together, and maybe need to be relatively at rest.

     

     

  23. I think I got it now.

     

    You're saying that light will travel one lightyear instantly but in doing so it will travel one year into the future so it still appears to have traveled at the speed of light.

     

    Is that right?

    I saw this comment on /. today: http://idle.slashdot...72&cid=33669610

     

    "When you travel at the speed of light, and you go to a place 45,000 light years away, you arrive the moment you left. No time passes. Just for the rest of us it seems like it takes a long time to get there, but for you in the craft, speed is infinite. If you want to get there in 5 minutes, you have to go a bit slower. If you want to arrive yesterday, then you'll have to go even faster than the speed of light...."

    I read this and thought, "Oh! So it's already known!" -- Well... the "faster than c" part is impossible.

    That comment though pretty much sums up my thoughts.

    Anywhere you travel, you will end up in the present. If you're in the same place as someone, you're both in the present of that location. "Traveling a year into the future" is misleading.

    But essentially yes, that idea is right. If you travel to a remote planet one light-year away, then one light-year (and more) of relative time (measured by a clock on the planet) will have passed, no matter what your speed is. Time dilation equations will tell you how "fast" that clock's time changes relative to your own clocks. (I think...)

    Here's another way to think of it: If you're looking right now at that planet that's a light-year away (and relatively at rest), you're seeing it as it was one year in the past. If you move toward it, when you get there, you will see it as it is in its present*. If you watch it as you move toward it, you will need to see it age from its "one year in the past" to its "present". This is a non-relativistic effect... time dilation makes it more complicated, and can add additional "time modifiers" let's say.

    I believe that special relativity says that you'll see most of its aging happen as you accelerate and decelerate (or when you "switch frames", as the Twin Paradox is usually explained). Its time will run faster than yours. In between, any time you are traveling at a constant relative velocity, you'll see its time slowed relative to yours.

     

     

    * Also note that time continues to pass, on the planet, so unless you make the trip instantly (calculated as relative v = c), then you'll actually see the planet age a year plus dilated travel time.

     

    Please help me here; I just don't understand the theory of relativity at all. It doesn't make sense to me. How can time slow the faster an object moves? Isn't time just a measurement? Doesn't that mean it follows the same rules as any other measurement? If we are talking about time as something more, like an entity of some sort, or an enrgy all of it's own, then maybe something like this would make sense, but if not, then going fast would just mean getting there sooner and going slower would mean getting there later. You can't just change the measurements because something is moving faster. That would be like saying grams weigh more the faster you increase the weight. No, you just have more weight because you added more weight. I don't know. I'm probably way off on this.

    Give me a month or a year or 105 years to figure out the details, and I'll be able to explain this!!!

     

    I promise a better explanation though...

  24. I am not sure. SOL has a specific value, roughly 300.000 km/sec. The inverse of this value (sec/km) is not zero.

    I'm not sure where inverses come in but we're talking about length contraction as described by the Lorentz transformation. As v approaches c, gamma (length contraction factor) approaches infinity.

     

     

    Note that if v = c, it's undefined (divide by zero), which confirms what I'm talking about: Imagining an observer at c leads to contradictions (loss of definition, paradoxes, whatever).

     

    I am not sure if we can apply such a word (instantaneously) to something that knows nothing about time. It could be 'infinitely" as well since we don't know whether t=o or t=infinite for a photon. I guess it's all wrong.

    I pretty much agree with the first sentence. I would sum it up as such:

     

    - There are no "observational frames of reference" for photons. Any reference frame that you imagine traveling at the speed of light is non-observational (if it's even valid at all).

    - Proper time is undefined for a photon. For all intents and purposes, time doesn't exist in non-observational frames.

     

     

    When we say something is "undefined" we don't mean it's infinite (the limit can approach infinity but it can also approach -infinity). We don't mean that it can be any value in between. It is undefined. Using it as a value in arithmetic or logic pretty much invalidates your conclusions.

  25. I was going to edit my last reply and say that my theory is wrong in its current form. I don't think I can say that light transmission is instantaneous without mixing up reference frames.

     

     

     

    From the initial photon's reference frame, it is standing still and the Earth and other planet are moving at the speed of light. So the photon sees the ultimate time dilation and length contraction. From the photon's point of view, the distance between the Earth and the other planet has contracted to zero. From the photon's point of view, it travels from the Earth to the other planet instantaneously! Any photon going from place to place (in a vacuum) goes at the speed of light. Thus for it, time is frozen (it never ages) and all distances are contracted to zero.

    Is this valid? Does a photon have a "point of view"? I think there is something wrong there, because in any valid frame of reference, the speed of light is constant c relative to the frame. What speed would a photon "see" other photons traveling at? I think we're talking about literally invalid things, and won't come to any completely paradox-free conclusions.

     

    I agree in principle... according to a photon, length is contracted to zero; it has no experience of "it's own time" passing (it has no frame within which you can describe a clock).

     

    However, if you say that it travels from the Earth to the other planet, you're speaking of a relative distance, and I think you have to use the relative time of that frame. So you can say that the photon travels no distance in no time (in it's own invalid frame). Or you can say that in moving from Earth to the the other planet, one year of time passes on the other planet, so the photon moves one light-year in one year, even if the photon "experiences" that passing of relative time in an instant.

     

     

    I'm not sure at all about what I'm saying here. I wonder if Einstein went through so many frame mixups and wrong interpretations of things as he figured it all out.

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