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Shut up thorin and go play with your bongThorin LungHammer said:
Newton works fine (here in this Universe). Go to the planet Mercury, and compute Mercury’s position while in orbit [around Mercury] using Newtonian mechanics – you’ll get the right answer
Relativity is meaningless without the concept of Point of View (i.e. an Observer, i.e. as per Copenhagen). If there were no observers then what exactly would things be Relative to, pray tell?
The Copenhagen Interpretation of QM (generally hated by A-Theists) clearly states that the waveform only collapses in the presence of an Observer!. In other words, reality doesn’t exist unless someone is looking.
Yeah … here’s the thing, when you are in orbit around Mercury … YOU are also experiencing the Relativistic effects of the Sun’s Gravity (just like Mercury). Time and Distance will be dilated for you when compared with an observer on the Earth. Because of this effect your measurements will physically differ from an observer back on Earth, and because of this dilation your Newtonian calculations will produce the correct result.
A result that – back on Earth – would require General Relativity to reproduce.
Without commenting on Trees falling in the woods … how often are math equations calculated when no consciousness is around? Do trees and rocks even understand mathematics?
Relativity is about Time and Distance dilation. Are you telling me that something other than a consciousness would even be aware of such an effect? How?
In addition to General Relativity, Einstein also developed the case of Special Relativity which asserts that the laws of physics are identical in all inertial frames. For this to be true, the speed of light cannot be different in different frames, even if those frames are in relative motion. This condition is met if the speed of light is a Universal constant. This finite communication time, which was not a component of Newton's description of gravity, allows for cause and effect relations which leads to the concept of Causality. Among many things, special relativity shows for objects moving at high velocity time runs slower, lengths become shorter and masses increase. This last effect can be understood through relativity as a relation between the increase of kinetic energy in one frame and a mass increase in another. This leads to the important principle of equivalence, E= mc2. The conditions of general relativity follow from those of special relativity but are applied to an accelerating frame (such as a gravitational potential). Hence inertial and gravitational forces are the same phenomenon and there is an identity between inertial masses as derived from Newton's laws of motion and gravitational masses which produce the force.
The basic prediction is that Newtonian gravity is very accurate when the gravitational field is weak (meaning that space is locally flat) but breaks down when the gravitational field is very strong (meaning space is locally curved). This was first manifested observationally when precision measures of the orbit of Mercury disagreed with Newtonian mechanics
But ONLY when measured from well outside the gravity field back on planet Earth! go to Mercury itself, and Space will seem just as "flat" as it did back on Earth ... Relative to You.
The resolution is provided by General Relativity. Mercury is sufficiently close to the Sun that it orbits in curved space and hence Newtonian mechanics provides an incomplete specification of its orbital parameters. The precession of the perihelion of Mercury's orbit and the bending of star light when it passes near the Sun are in excellent agreement with predictions from General Relativity and serve as its best verification.[
The basic prediction is that Newtonian gravity is very accurate when the gravitational field is weak (meaning that space is locally flat) but breaks down when the gravitational field is very strong (meaning space is locally curved). This was first manifested observationally when precision measures of the orbit of Mercury disagreed with Newtonian mechanics
But ONLY when measured from well outside the gravity field back on planet Earth! go to Mercury itself, and Space will seem just as "flat" as it did back on Earth ... Relative to You.
The resolution is provided by General Relativity. Mercury is sufficiently close to the Sun that it orbits in curved space and hence Newtonian mechanics provides an incomplete specification of its orbital parameters. The precession of the perihelion of Mercury's orbit and the bending of star light when it passes near the Sun are in excellent agreement with predictions from General Relativity and serve as its best verification.[
Tricky
Briefly immortal
When you copy someone else's work, Franko, you are supposed to cite the reference. Otherwise it is plagarism.
Of course, there was never any question that you did not write the previous post. It was comprehensible.
Of course, there was never any question that you did not write the previous post. It was comprehensible.
Tricky
Briefly immortal
If you're using Internet Explorer, go into View --> Toolbars and make sure address bar is checked. That way the website address will appear at the top of your browser page.Franko said:
Stimpson J. Cat
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Franko,
This is false. The curvature of space is a local quantity, and can be measured (in principle) on an arbitrarily small distance scale (at least, until you get down to the quantum scale). It is nonzero both on Mercury and on Earth. It is just much easier to measure over large distance scales.
The curvature of space can be measured as follows. Take three points in space. Connect those points with straight lines (where a straight line is defined to be the shortest path connecting two points). You now have a triangle. Add up the angles. If they do not add up to 180 degrees (pi radians), then space is curved.
The average curvature over the triangle can then be calculated as the sum of the angles (in radians), minus pi, divided by the area of the triangle.
Although it is not obvious from the above, as we take the limit of the triangle's area going to zero, the average curvature does not go to zero. Instead, it approaches a finite limit, which is the local curvature.
Dr. Stupid
This is false. The curvature of space is a local quantity, and can be measured (in principle) on an arbitrarily small distance scale (at least, until you get down to the quantum scale). It is nonzero both on Mercury and on Earth. It is just much easier to measure over large distance scales.
The curvature of space can be measured as follows. Take three points in space. Connect those points with straight lines (where a straight line is defined to be the shortest path connecting two points). You now have a triangle. Add up the angles. If they do not add up to 180 degrees (pi radians), then space is curved.
The average curvature over the triangle can then be calculated as the sum of the angles (in radians), minus pi, divided by the area of the triangle.
Although it is not obvious from the above, as we take the limit of the triangle's area going to zero, the average curvature does not go to zero. Instead, it approaches a finite limit, which is the local curvature.
Dr. Stupid
So what are you saying Stimp?
Relativity accounts for dilation, Newton doesn't --correct?
That was the difference between the two -- correct? If not, then why did everyone get so excited about Einstein?
So if the reason that Mercury is miscalculated from Earth is because of dilation, are you saying that a person in orbit around Mercury wouldn't also feel the effects of this same dilation?
Relativity accounts for dilation, Newton doesn't --correct?
That was the difference between the two -- correct? If not, then why did everyone get so excited about Einstein?
So if the reason that Mercury is miscalculated from Earth is because of dilation, are you saying that a person in orbit around Mercury wouldn't also feel the effects of this same dilation?
neutrino_cannon
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Franko:
That would apear to be his case.
The only reason I included relativity in my post was to point out that we have come a long way from newtonian physics, and that the emerging field of quantum physics, which according to the link I posted http://spot.colorado.edu/~vstenger/Quantum/qkids.html
shows, along with many others that quantum physics is in complete accord with all observed data. Furthermore, for reasons explained in the link, quantum physics show that individual reactions between particles are randomized.
Thus, as the nature of the universe is at a quantum level, random, fatalism cannot be true.
I posit this not because it is a dogmatically held belief, as you would have the world know, but because that is what all the evidence points too, as posted above.
That would apear to be his case.
The only reason I included relativity in my post was to point out that we have come a long way from newtonian physics, and that the emerging field of quantum physics, which according to the link I posted http://spot.colorado.edu/~vstenger/Quantum/qkids.html
shows, along with many others that quantum physics is in complete accord with all observed data. Furthermore, for reasons explained in the link, quantum physics show that individual reactions between particles are randomized.
Thus, as the nature of the universe is at a quantum level, random, fatalism cannot be true.
I posit this not because it is a dogmatically held belief, as you would have the world know, but because that is what all the evidence points too, as posted above.
Stimpson J. Cat
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Franko,
I thought that was clear. I am saying that what you stated is wrong.
If someone living on Mercury were to use Newtonian mechanics to calculate its orbit, they would get a different answer than we get here on Earth (due to time dilation and length contraction). But the answer they get would still be wrong, even from their own frame of reference.
Why you think this is relevent is beyond me, though. Either way, Newtonian relativity is wrong. End of story.
Dr. Stupid
I thought that was clear. I am saying that what you stated is wrong.
If someone living on Mercury were to use Newtonian mechanics to calculate its orbit, they would get a different answer than we get here on Earth (due to time dilation and length contraction). But the answer they get would still be wrong, even from their own frame of reference.
Why you think this is relevent is beyond me, though. Either way, Newtonian relativity is wrong. End of story.
Dr. Stupid
Stimpson J. Cat
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Franko,
Yes.
Space-time curvature. Time dilation and distance contraction are both manifestations of space-time curvature (as well as Special Relativity). They are not sufficient to completely describe General Relativistic gravitational effects, though. The effect of GR on the orbit of Mercury is far more complicated than you seem to think it is.
Dr. Stupid
Yes.
Space-time curvature. Time dilation and distance contraction are both manifestations of space-time curvature (as well as Special Relativity). They are not sufficient to completely describe General Relativistic gravitational effects, though. The effect of GR on the orbit of Mercury is far more complicated than you seem to think it is.
Dr. Stupid
So what else is there SPECIFICALLY?
You mention Time and Distance dilation (which is the result of the curvature of spacetime). But you seem to be implying that there is another component that would not be fully accounted for by a person standing in the same gravity field as Mercury itself. What is the other component?
How so? I thought the difference between Newton and Einstein was Relativity (curvature of spacetime by gravity)? You seem to be saying there is something else? … what is the something else?
Stimpson J. Cat
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Franko,
What you are asking me to explain is not only far to complicated for me to try to explain on a message board, it would also require me to teach you Tensor Calculus.
No, I am saying that there is more to spacetime curvature than just time dilation and distance contraction.
For one thing, Mercury is not in a circular orbit. That means that the gravitational strength, and the resulting deviations from Newtonian physics, vary as a function of time. Your assumption that all of the non-Newtonian effects of GR will cancel out if all your measurements are done within the same frame as Mercury, would only be valid if Mercury were in a Uniform gravitational field. It is not.
But you don't have to take my word for it. Go to the Library and check out a book on General Relativity (a textbook, not some popular-science book that introduces a bunch of intuitive analogies, and glosses over the math).
Of course, you would be advised to learn the necessary math first. There is a reason General Relativity is tought as an advanced level physics course.
Dr. Stupid
What you are asking me to explain is not only far to complicated for me to try to explain on a message board, it would also require me to teach you Tensor Calculus.
No, I am saying that there is more to spacetime curvature than just time dilation and distance contraction.
For one thing, Mercury is not in a circular orbit. That means that the gravitational strength, and the resulting deviations from Newtonian physics, vary as a function of time. Your assumption that all of the non-Newtonian effects of GR will cancel out if all your measurements are done within the same frame as Mercury, would only be valid if Mercury were in a Uniform gravitational field. It is not.
But you don't have to take my word for it. Go to the Library and check out a book on General Relativity (a textbook, not some popular-science book that introduces a bunch of intuitive analogies, and glosses over the math).
Of course, you would be advised to learn the necessary math first. There is a reason General Relativity is tought as an advanced level physics course.
Dr. Stupid
Yeeeaaah Budddy … but here is the thing … if you are in a spaceship orbiting Mercury … and you are doing your simply little Newtonian calculations on a computer. Then as you moved through the changing Gravitational field (Information density) then wouldn’t the Relativistic effects also be changing right along with you (and Mercury as it moved around closer and farther from the Sun). In other words, Time dilation and Distance dilation would be effecting MERCURY, YOU, your SHIP, and the COMPUTER, and ergo your calculations?
Okay, so essentially what you are telling me is that Newtonian mechanics is wholly dependant on the precise orbital position of the Earth? If our Earth were some how moved to the orbit of Mercury, Newton would have been just another knucklehead?
Stimpson J. Cat
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Franko,
Like I said, the effects don't cancel out. I am sorry if this seems counter-intuitive to you. You don't have to take my word for it. Do the math.
No, I am saying that, as an approximation to reality, Newtonian mechanics works better at the orbital position of the Earth, then it does at the orbital position of Mercury. It doesn't give the right answer for the orbit of the Earth, either. The answer it gives is just much closer to the actual orbit, than it is for Mercury.
No, but we would have discovered that his laws of motion were flawed sooner.
Dr. Stupid
Like I said, the effects don't cancel out. I am sorry if this seems counter-intuitive to you. You don't have to take my word for it. Do the math.
No, I am saying that, as an approximation to reality, Newtonian mechanics works better at the orbital position of the Earth, then it does at the orbital position of Mercury. It doesn't give the right answer for the orbit of the Earth, either. The answer it gives is just much closer to the actual orbit, than it is for Mercury.
No, but we would have discovered that his laws of motion were flawed sooner.
Dr. Stupid