Space-time curvature is incorrect

Discussion in 'Physics & Math' started by Frencheneesz, Aug 26, 2002.

  1. Frencheneesz Amazing Member Registered Senior Member

    Messages:
    739
    AHHHHHHHH, i think im going to go crazy today. I THOUGHT i posted yesterday, but ... its not here. WHY!!!! I won't tell you the other reasons, but anyway....

    let me see if I can remeber, these wont be as in depth as I wanted them to be unless by accident, Im lazy

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    "Where the field is weaker, clocks run faster than where the field is stronger."

    Ok, does this mean that an object in the center of two equally strong gravitational fields will have no effect imposed on it because the gravitational fields are "opposite" in a sence, or will the gravitational "fields" add up to greate a greater time dialation? In other words is the dialation related to the net pull or the average pull?

    "In general relativity (GR), acceleration and gravity are indistinguishable."

    Acceleration and gravity ARE different. You can be accelerating while not under the influence of gravity and, likewise, you can be under the influence of gravity and not be accelerating! They cannot be the same thing.
    If you go by an accelerometer which "can't tell the difference between gravity and acceleration" it will register acceleration when you are not accelerating but when you are standing on a planet, yet when you are accelerating in free-fall, an accelerometer will tell you otherwise.

    Gravity is a force, acceleration is the actual movement. Gravity is like the moter of a car, the driving force, while the acceleration is the action, moving the car. If you are stuck in mud, the moter/gravity might not accelerate you because the wheels will turn but you will not go. Im sure I don't need to explain it to you like this.

    "He sees the light received at the same time, but he knows the light from the front end of the spaceship has less distance to travel, so he concludes that it must have been emitted later."

    Heh, makin' myself sound stupid again. I read the example wrong. But if the two observers were situated like you said they were, it would be impossible for them both to visualy register the lights go on at exactly the same time (unless of course they were human in which their eyes might not have enough fps to tell the difference).

    Maybe im still not getting it, what does the different frames of refference have to do with it? And you were unclear on what the second observer saw, did he see the two lights at the same time, or did he observe the first observer?

    "The "receiving the light" event happened at the same time for both torches and both observers."

    There was two "receiving the light" events, one for the first observer and one for the second observer.

    "Logic is not always that same thing as truth." - Rav

    Ill keep that in mind. By the way, do you understand how one event can happen at two different times?
     
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  3. Frencheneesz Amazing Member Registered Senior Member

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    "there are 6 dimensions directly/indirectly influencing) to spacetime"

    Are you implying that the other 4 arent influential? (there are 10 in String theory)

    Splock:

    Why don't we set up a time to have like an AIM chat room thing, I don't know anyone who has icq or anything, but um, well what do you have?
     
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  5. James R Just this guy, you know? Staff Member

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    Frencheneesz,

    <i>does this mean that an object in the center of two equally strong gravitational fields will have no effect imposed on it because the gravitational fields are "opposite" in a sence, or will the gravitational "fields" add up to greate a greater time dialation? In other words is the dialation related to the net pull or the average pull?</i>

    Net pull. An object at the centre would have have minimal time dilation.

    <i>Acceleration and gravity ARE different. You can be accelerating while not under the influence of gravity and, likewise, you can be under the influence of gravity and not be accelerating! They cannot be the same thing.</i>

    You're thinking in a Newtonian rather than GR sense. In GR, free-fall motion is unaccelerated, whereas in Newtonian mechanics free-fall motion is accelerated. Additional acceleration not due to gravity is also possible in GR.

    <i>If you go by an accelerometer which "can't tell the difference between gravity and acceleration" it will register acceleration when you are not accelerating but when you are standing on a planet, yet when you are accelerating in free-fall, an accelerometer will tell you otherwise.</i>

    Yes. That's why GR says that free-fall motion is unaccelerated. It is indistinguishable from unaccelerated motion by any local measurement.

    <i>Gravity is a force, acceleration is the actual movement.</i>

    That's true in Newtonian physics, but not according to GR. Gravity in GR has to do with curved spacetime. It is not a force.

    <i>But if the two observers were situated like you said they were, it would be impossible for them both to visualy register the lights go on at exactly the same time (unless of course they were human in which their eyes might not have enough fps to tell the difference).</i>

    We only have one person registering the light - the person standing in the centre. The other observer, in relative motion, is watching that person receiving the light.

    <i>Maybe im still not getting it, what does the different frames of refference have to do with it? And you were unclear on what the second observer saw, did he see the two lights at the same time, or did he observe the first observer?</i>

    Different frames of reference are simply different points of view on the same events. Different points of view have different ideas of simultaneity. That is what this example demonstrates.

    The second observer observed the first observer.

    <i>There was two "receiving the light" events, one for the first observer and one for the second observer.</i>

    No. The second observer is watching the first observer. We are not interested in whether or when the light reaches the second observer. That is a different event. We're interested in how the two observers see the <b>same</b> events.
     
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  7. Splock Registered Member

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    further discussion

    You people make my soul swell with pride; in the human race.
    Nothing quite like hearing a rousing discussion by people with uncommon sense, touching on the inherent truth.


    time is proportionally speeding up, exponentially in an 7thdimensional transform, which is also a recursive sequence, scalar proportionality from/leading to an 9th dimensional transform......

    everything is due to nthdimensional transforms, in which each dimension is bot defined by, and greater than, the two dimension sequences behind it.

    i-omega defines x, i-omega-x defines y, which define z, X-Y- Z define t..... xyz and t define n, x-y-z-t and n defines omega, which has a dual nature, which defines i. i defines omega. though t defines n, n is t-, n is greater than, and equal to R.


    omega, x, y,z,t,n,omega,i, R, omega,, are the 10 transforms

    R is recursion, which exists outside of time. (8thD)


    novelty and time together define hypertime and hyper n, which only exist in an infinate pair (Th), and R is the converse.

    the AIM chat is a good thing, though I'll have to actually organize my book of notes.

    ( I know this concept is counter-intuitive and inherently against "logic", but only numerological logic.... after the 6thd, numbers don't exist. I can show you the equations, but as you might guess, they are increasingly defined by imaginary numbers, the more specific you get to 7+dimensional values.

    luckily, thanks to the nature of reality not being based on defined numbers and constants, it's very easy to refine once you understand the basis.......
     
  8. Frencheneesz Amazing Member Registered Senior Member

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    739
    I wonder if anyone would like to read our posts and respond to them other than me and James R........

    "In GR, free-fall motion is unaccelerated"

    OK, in free-fall, you are accelerating toward the earth relative to the earth. In otherwords, you can have a relative speed, therefore you can have a relative acceleration. You DO have this relative acceleration toward the earth in free-fall, do you agree?

    "That's why GR says that free-fall motion is unaccelerated."

    I'm sorry, but an accelerometer is a very poor thing to base an entire theory base on. If you look at how an accelerometer is constructed, you will see that it is nothing more than a single-point pressure sensor. The more pressure above or below the "0" point is greater acceleration.
    Thus it is not a true accelerometer, it is only a helper. Using human ingenuity we can find the differences between acceleration and Gravitic pull, which is to say there is a noticible difference.

    "Gravity in GR has to do with curved spacetime. It is not a force."

    When you say gravity creates no force, are you meaning to say it has no force associated with it? Because if it had no force associated with it, it would not be possible to gain power from a waterfall, or rivers, neither would it be possible for gravity to change the velocity of an object.

    Are you contesting the theory that "an object at rest will remain at rest unless acted on by an outside force"?

    By the way, your example was very hard to understand without reading it again and again and again and again. So maybe youd like to create a new one?

    "However, the distance the light had to travel from the torch at the front of the spaceship is less than the distance it had to travel from the rear of the spaceship, because you, standing in the middle, are moving forwards all the time according to this observer."

    Do you mean to say that the ship was accelerating?

    I see no way in which this example can work: if the ship is accelerating either it would be impossible for the first observer to see the two lights turn on simultaneously (newtonianly) or the second observer would have to induce that light travels at the same speed in relation to all objects (relatively) and deduce the same thing as the first observer.
    If the ship is not accelerating: then both observers should still agree.

    'Different frames of reference are simply different points of view on the same events.'

    I thought that frames of reference were defined by the speed until you enlightened me into thinking that it has to do with speed acceleration and gravity. A point of view is much broader, having to do with morals and scenes.
     
  9. James R Just this guy, you know? Staff Member

    Messages:
    39,397
    Frencheneesz,

    Here is a link to essentially the same example I gave you regarding relativity of simultaneity. The diagrams might help you a little:

    <a href="http://www.phys.uidaho.edu/~pbickers/Courses/310/Notes/book/node58.html" target="_blank">Relativity of Simultaneity</a>

    Your issues with gravity are quite separate from the simultaneity issues. Simultaneity needs only special relativity, whilst gravity requires general relativity.

    <i>OK, in free-fall, you are accelerating toward the earth relative to the earth. In otherwords, you can have a relative speed, therefore you can have a relative acceleration. You DO have this relative acceleration toward the earth in free-fall, do you agree?</i>

    According to Newton, yes. According to Einstein, no.

    <i>I'm sorry, but an accelerometer is a very poor thing to base an entire theory base on.</i>

    The theory isn't linked to any particular form of technology. The basis is that there is no experiment you can do in gravitational free-fall which can distinguish that state of motion from floating free and stationary in space far from a gravitational field. If you dispute that, please provide a suggested experiment.

    <i>Using human ingenuity we can find the differences between acceleration and Gravitic pull, which is to say there is a noticible difference.</i>

    I do not believe this is true. How could we determine the difference?

    <i>When you say gravity creates no force, are you meaning to say it has no force associated with it? Because if it had no force associated with it, it would not be possible to gain power from a waterfall, or rivers, neither would it be possible for gravity to change the velocity of an object.</i>

    That's not true in the GR picture.

    <i>Are you contesting the theory that "an object at rest will remain at rest unless acted on by an outside force"?</i>

    Yes. Only an object in inertial motion will remain in that unchanged state if no forces act. Free-fall motion is inertial. Objects in free-fall follow geodesics in spacetime with no force required. An object in a gravitational field needs another force to stop it from free-falling. (This is the GR picture.)

    <i>By the way, your example was very hard to understand without reading it again and again and again and again. So maybe youd like to create a new one?</i>

    Let's see if we can get you to understand the first one.

    <i>Do you mean to say that the ship was accelerating?</i>

    No. It is moving at constant speed relative to the outside observer. In other words, the outside observer is watching it fly past.

    <i>If the ship is not accelerating: then both observers should still agree.</i>

    I've already explained why they do not. See also the above link.
     
  10. Rav Valued Senior Member

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    2,422
    James R's staying power in this discussion is impressing me. I don't think I could do it. There have been other people as well. And Frencheneesz, you seem to have an endless reserve of energy which fuels your quest to understand everything. That's great! I can relate to that, although I go about it in a different way.

    You're a very intelligent guy Frencheneesz. It's easy to recognize, and it's probably why people have devoted as much time as they have to you and this thread. But you would have sucked the life out of me by now as far as it relates to this discussion. Perhaps that is a failing of my own. I certainly don't mean anything personal by it.

    What I have to say is this. I really think you should do some reading on your own, but I remember you making a comment atleast once in this thread concerning the fact that you had an aversion to it. You'd rather deal with it here. But misinterpretation is becoming a real hinderance. Am I the only one noticing it? It's better I think to get a really firm grasp on the core aspects, and then come here for clarification if you need it.

    Einstein himself is perfect for you. He goes to incredibly uncommon lengths to cover every base, no matter how trivial or unrelated things might initially seem, to ensure that you develop a proper and completely accurate understanding of what he's talking about. I'm betting he learned to do that so well because he had to. Anyway, here's a link to an online version of his book "Relativity: The Special and General Theory ".

    http://www.marxists.org/reference/archive/einstein/works/1910s/relative/index.htm

    If that doesn't work for you, then there are some great books around. I can't stress enough that it would be almost absolutely impossible (and certainly relatively impossible) to gain a thorough understanding of his theories from a message board, even in view of the fact that this one is visited by some extremely insightful, intelligent and helpful people who have a passion for science, philosophy and mathematics.

    EDIT: But if anyone is up to the challenge, then by all means. James R is obviously taking a crack at it

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  11. Frencheneesz Amazing Member Registered Senior Member

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    "According to Newton, yes. According to Einstein, no. "

    You have said this enough times to drill the pharse into me, i think what this question was meant for is an explanation.

    "The basis is that there is no experiment you can do in gravitational free-fall which can distinguish that state of motion from floating free and stationary in space far from a gravitational field."

    I can't answer that unless we agree on what acceleration is.

    "That's not true in the GR picture."

    Care to shed light on this GR picture and its reasoning?

    "Only an object in inertial motion will remain in that unchanged state if no forces act."

    Define inertial motion. It seems a lot of these disputes are about definition.

    "No. It is moving at constant speed relative to the outside observer. In other words, the outside observer is watching it fly past. "

    I understand everything about the example exept for how the second observer deduces that the timing was not simultaneous. I wonder if you could EXPLAIN this. You like to recite stuff, but your explanations are lacking.
     
  12. Splock Registered Member

    Messages:
    9
    Newton ----------------------<=> bad!

    newton was/needed to be poked with the "pointy stick of learning", anti-"time's arrow", right in the eye.


    then he could see the relativity of binary singualarity with a bit of a better perpective.............. = D
     
  13. James R Just this guy, you know? Staff Member

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    39,397
    Frencheneesz,

    Did you read the page I linked to?
     
  14. Frencheneesz Amazing Member Registered Senior Member

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    James R:

    Yes, it was almost exactly like your example, therefore it helped minimally. Did you read my post?
     
  15. Frencheneesz Amazing Member Registered Senior Member

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    Rav:

    "But you would have sucked the life out of me by now as far as it relates to this discussion. "

    Ha, my intention all along. Im a thought vampire. But seriously, im sorry. I think the main problem is that whoever disagrees with me disagrees because we have an incongruent understanding of the basics (i think you said that in some form). James R is talking about gravity and acceleration, we seem to have a different definition of acceleration; that is what I mean.

    I'm sorry if i said I wouldn't read on my own, but i've tried that. I would gladly get the books you prescribed, but i haven't gotten around to it yet. And I doubt that the theories we have explain the real world as it is perfectly, so... we could discuss it here. In a book I could only gain what he thought i needed, if i need more i can come here.

    I was thinking that these forums are for a ton of people to see and rather than one person duking it out with me, it would be great if we could have many people with all their different understandings come and help out

    Well, back to the game plan:

    http://www.marxists.org/reference/archive/einstein/works/1910s/relative/ch09.htm

    In this example, the second observer actually sees the light, he is stupid and thinks that since the light on the left got to him first, it happened first.

    This is different than James R's example since the 2ond observer observed the first observer, not the light itself.

    "I can't stress enough that it would be almost absolutely impossible to gain a thorough understanding of his theories from a message board"

    Only if you are starting from scratch, which i am not.

    I have an idea: Since I like to think about things starting from a few basic truthes, the prime numbers of understanding, then would it be possible for you (James R) to list the probably very few basic truths of relativity?

    Ill give you the basic truths of my (semi-newtonian) phisical ideas as an example:

    1 The universe is constructed of only particles in relative motion (in other words, energy doesn't exist save motion)
    2 All particle interactions involve one or more of the fundemental forces (number left out to leave room for additions or combinations)
    3 All knowable particles emit a force
    4 An object in motion (including rest) will remain in that inertial state until acted on by an ouside force
    5 Nothing is random
    6 Gravity is directly related to mass
    7 mass is directly related to inertia
    8 Law of conservation
    9 distance is relative
    Derivation 1: #7 All Particles must have mass, 0 mass particles would have no inertia
    Derivation 2: #9 , speed is change in distance, therefore speed is relative
    Derivation 3: Derivation 2, acceleration is change in speed, therefore acceleration is relative

    There, this is an example of what my idealism is based on.

    I don't want to burn anyone out, but I am trying to gain better understanding, but my ideas should also let others gain either more understanding of the universe, or a better understanding about what they already know.

    For some people, like religious believers, it ends up in both sides understanding what the other is talking about, just disagreeing. In our case, the problem is not disagreement, but understanding. SO, if it were up to me, id like to continue the understanding process. You know you don't have to devote your life to it!
     
  16. James R Just this guy, you know? Staff Member

    Messages:
    39,397
    Frencheneesz,

    Ok then. My definition of acceleration is:

    "Acceleration is the second derivative of the co-ordinate position with respect to time." In other words, it is the rate of change of velocity, which in turn is the rate of change of co-ordinate position.

    According to GR, an object in free-fall has no acceleration by this definition.

    <i>Well, back to the game plan... In this example, the second observer actually sees the light, he is stupid and thinks that since the light on the left got to him first, it happened first.</i>

    This example is essentially the same. The result has nothing to do with whether one observer is smart or stupid. Replace the observer by a television camera or something and you'll get exactly the same result.

    Let's look at your list:

    <i>1 The universe is constructed of only particles in relative motion (in other words, energy doesn't exist save motion)</i>

    The first part is reasonable. The part in brackets requires a definition of energy. In physics we often talk of potential energy, which exists quite apart from motion.

    <i>2 All particle interactions involve one or more of the fundemental forces (number left out to leave room for additions or combinations)</i>

    Yes, provided your meaning of "interactions" is the same as mine.

    <i>3 All knowable particles emit a force </i>

    A force in physics is not usually considered to be "emitted". It is something applied in an interaction.

    <i>4 An object in motion (including rest) will remain in that inertial state until acted on by an ouside force</i>

    If "motion (including rest)" is defined precisely as "inertial state", then this is ok.

    <i>5 Nothing is random</i>

    Quantum mechanics goes against this.

    <i>6 Gravity is directly related to mass</i>

    Yes. More accurately mass-energy.

    <i>7 mass is directly related to inertia</i>

    Yes.

    <i>8 Law of conservation</i>

    Which one?

    <i>9 distance is relative</i>

    Yes.

    <i>Derivation 1: #7 All Particles must have mass, 0 mass particles would have no inertia</i>

    Depends what you mean by "inertia". Photons have momentum but no rest mass, for example.

    <i>Derivation 2: #9 , speed is change in distance, therefore speed is relative</i>

    Yes.

    <i>Derivation 3: Derivation 2, acceleration is change in speed, therefore acceleration is relative</i>

    Yes.
     
  17. zanket Human Valued Senior Member

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    3,777
    Frencheneesz:

    I've learned there are 2 types of science books: those I understand, and those I don't. If I don't understand it, I blame the author.

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    Maybe you just haven't read one by a good author. At amazon.com you can see excerpts of the books, to see if the author speaks to your level.

    This is a stumbling block for you. The first observer may see the lightning strikes as simultaneous. A third observer may see the right strike happen first. Which observation should the second observer call the truth? A reasonable person would call his own observation true for himself, that the left strike happened first from his perspective, and further that the order of events depends on your perspective.
     
  18. Frencheneesz Amazing Member Registered Senior Member

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    739
    "At amazon.com you can see excerpts of the books, to see if the author speaks to your level. "

    If the book doesn't have math in it (or not much) its at my level. What i meant is that i haven't gotten more books YET. I will later.

    "Which observation should the second observer call the truth?"

    My point is that the observers not only have to see the event, but also apply them to the laws of geometry. If the person SEES a light go off first and another second, to tell the laps (or if there is no laps) between events, then the observer must measure distances between events and himself and take a look at it from there.

    James R had a much better example only because it had a better argument. It involved different frames of refference. Aulthough i either do not understand it, or i do not agree with his example is correct, it is much better than one that we both agree is wrong. He said that two observers in the same frame of refference will observe things to be the same, and the example that I linked to had two observers in very similar if not perfectly similar frames of refference. Not to mention the second observer of that one didn't apply his observation to the laws of geometry.
     
  19. Frencheneesz Amazing Member Registered Senior Member

    Messages:
    739
    "According to GR, an object in free-fall has no acceleration by this definition. "

    No acceleration relative to what? In relativity, the reference point is very important. Im sure the free-fall object is acclerating toward SOMETHING. I was saying that it was accelerating toward the point of gravitational force (ie relative to the earth), would you agree?

    "The result has nothing to do with whether one observer is smart or stupid."

    "Hence the observer will see the beam of light emitted from B earlier than he will see that emitted from A. Observers who take the railway train as their reference-body must therefore come to the conclusion that the lightning flash B took place earlier than the lightning flash A."

    The stupid part comes in when the observer (ie not a camera) comes to a conclusion (ie thinks, something a camera cannot do). This is different from James R's example where the observer was doing his utmost to understand the situation, the observer in the linked example just jumped to a conclusion without applying his observation to the laws of geometry, thus he is stupid, or forgetful, or absent minded, or he doesn't care enough, etc.

    "The part in brackets requires a definition of energy."

    I said that this "energy" does not exist, only particles and motion. This is to avoid the arbitrary definition of energy, which is usually "the ability to do work". This works very nicely to relieve the need of the mass-energy scheme.

    Potential energy could be described in this way by saying it is the potential for something to create motion (including, kinetic, heat, sound, ect)

    May I remind you that these are MY ideas not THE True truths. These axioms are examples for you, so that you can put down your own axioms about relativity.

    "A force in physics is not usually considered to be "emitted"."

    For lack of a better pharse, i used this one.

    "If "motion (including rest)" is defined precisely as "inertial state", then this is ok. "

    I was sketchy about what the connotation of inertial state was. What is your definition of "inertial state", because I don't have one?

    - Nothing is random-

    "Quantum mechanics goes against this. "

    If the definition of random is without structure in the form of phisical laws, then I hold true with my saying. If Random means the inability to predict the movements of things, then I would still argue against randomness, but the uncertainty princible would be there to contradict me.

    -8 Law of conservation -

    "Which one?"

    By your definition that it is "More accurately mass-energy", then it shouldn't matter. The two laws state the same thing replacing one word for its synonym.

    "Depends what you mean by "inertia". Photons have momentum but no rest mass, for example. "

    What do you mean by inertia? Wouldn't you think it would work if light traveled at close to "light speed" and had a minicule amount of mass? What wouldn't work about THAT?

    Would you mind writing a list of axioms for Relativity as i have done for my ideas? This is what I was getting at in the first place. I'm sure relativity couldn't have too many basic "truths" to write, right?
     
  20. zanket Human Valued Senior Member

    Messages:
    3,777
    Frencheneesz:

    And then what? You could figure out what another observer would have seen, such as simultaneous strikes. Would you then adopt their observation over your own? Why?
     
  21. James R Just this guy, you know? Staff Member

    Messages:
    39,397
    Frencheneesz,

    <i>No acceleration relative to what? In relativity, the reference point is very important. Im sure the free-fall object is acclerating toward SOMETHING. I was saying that it was accelerating toward the point of gravitational force (ie relative to the earth), would you agree?</i>

    That is a complex question. GR is what's called a "local" theory of spacetime. Observers at a distance can and do see things quite differently to observers who are "local" to the object under consideration. In fact, the main thing the theory does is to tell us how to convert the observations of one observer into observations of another at a distance.

    GR does not describe free-fall as acceleration in the local sense. A person in free-fall under gravity feels no acceleration and no force from gravity. A person standing on the surface of the Earth will see a falling person as accelerating towards him or her, but the reason for this is different in GR than in Newtonian physics. In Newtonian physics gravity is a force which causes falling objects to accelerate. In GR, the Earth's surface is accelerating the Earthbound observer <i>upwards</i> in spacetime towards the free-falling object.

    This is difficult to understand and also difficult to explain.

    <i>What is your definition of "inertial state", because I don't have one?</i>

    An inertial frame of reference is one in which all the laws of physics take their normal forms, with no mysterious "inertial" forces required to explain observed results. It is <i>only</i> in inertial frames that laws like F=ma work without modification.

    <i>What do you mean by inertia?</i>

    The term "inertia" is usually interchangeable with "mass" as far as I am concerned. "Inertial reference frame" is defined above, and is a somewhat more complex concept.

    <i>Wouldn't you think it would work if light traveled at close to "light speed" and had a minicule amount of mass? What wouldn't work about THAT?</i>

    No, it wouldn't work. For instance, the theory of quantum electrodynamics (QED) relies on the fact that photons have no rest mass. QED is perhaps our most accurate scientific theory. It has been experimentally verified to about 10 significant figures, from memory.

    <i>Would you mind writing a list of axioms for Relativity as i have done for my ideas?</i>

    Ok. Here are the axioms of general relativity:

    1. Spacetime is a 4-dimensional manifold which has a locally flat (Minkowski) metric.

    This means that special relativity applies locally.

    2. Particles in free-fall follow timelike geodesics on the manifold.

    This means that without forces particles tend to follow free-fall trajectories.

    3. All physical laws that hold in flat Minkowski space (ie. "special relativity") and are expressible in terms of vectors and tensors, and are meaningful in the 4 dimensional manifold, continue to hold in every reference frame (provided we replace derivatives by a special type of derivative known as a "covariant derivative").

    This is often called the Strong Equivalence Principle.
     
  22. Frencheneesz Amazing Member Registered Senior Member

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    ok youve lost me on the local and "from a distance" stuff... like, how distant is from a distance, and what does it exactly matter how far something is from something else?

    "the Earth's surface is accelerating the Earthbound observer upwards in spacetime towards the free-falling object."

    I have discussed this with someone (i don't remeber who) and we came to the conclusion that: given that matter COULD be accelerating in all directions at once, then there are no problems with that theory. What I don't understand is HOW matter could do that.

    Another thing we agreed on is that there MUST be some force that accelerates mass outwardly. Can you atest to this?

    "An inertial frame of reference is one in which all the laws of physics take their normal forms"

    So, how many factors is there for it. In a frame of reference as I originally thought the only factor was speed, then you introduced acceleration and gravitational pull (or push if you want). Are there yet other factors for the inertial frame?

    -Wouldn't you think it would work if light traveled at close to "light speed" and had a minicule amount of mass? What wouldn't work about THAT? -

    "No, it wouldn't work."

    Would you mind giving an example of why that wouldn't work?

    "Here are the axioms of general relativity: "

    Those are all of them? I won't discuss them now, because i should try to understand them first.

    catch you later
     
  23. Frencheneesz Amazing Member Registered Senior Member

    Messages:
    739
    Zanket:

    "Would you then adopt their observation over your own? Why?"

    My point was that I don't care what i SEE, I care what happened. If I see something distorted through water (lets say a spoon), we cannot say that the spoon is bent in our frame of reference, we have to come to the conclusion that the course of the light hitting the spoon was altered.

    Not to mention that he can actually see that one light beam had to travel farther. If someone gets a letter from the guy next door, today, and a letter from Africa the next day, one cannot assume that the letter from next door was written first.
     

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