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If the beam is straight then if the photon-bullet is at all times in line with the beam then that indicates no gravity field -- or if the photon-bullet is crabbing-skidding then that indicates the presence of a gravity field
Quote from: mad aetherist on 15/12/2018 20:49:32I think that it is ok to insist on non-local inputs. However in the case of my far-away starlight i think that that should be acceptableThen the task is trivial. No need to consider photons. The star is not accelerating with you, so just watch the star and if it seems to accelerate, it is you that is actually accelerating. Measuring the bending of light is totally unnecessary.
I think that it is ok to insist on non-local inputs. However in the case of my far-away starlight i think that that should be acceptable
I crunched some numbers in Excel. For a 10 m wide elevator & g = 9.8 m/s/s a beam travelling at 300,000 kmps will fall 5.44 pico mm (mm^-12) measured at the far wall, & the beam angle at the wall (ie the tangent to the curve) will be 0.2235 pico arcsec (arcsec^-12). This is a simple ballistic calculation (ie as per Soldner)(ie as per Newton).
Quote from: mad aetherist on 16/12/2018 02:02:21If the star is nearby then u could cheat in that way, but i am talking about a distant star, meaning a distant galaxy of course. Here u could cheat by using that to tell u if any rotation of the elevator (at least in one or two planes)(it couldnt tell u about all 3 planes).Rotation is absolute, so I don't need to look out the window to detect rotation. Rotation is about one axis, not one or more planes.A super-distant star is functionally the same as a light source bolted to the box.
If the star is nearby then u could cheat in that way, but i am talking about a distant star, meaning a distant galaxy of course. Here u could cheat by using that to tell u if any rotation of the elevator (at least in one or two planes)(it couldnt tell u about all 3 planes).
QuoteOne problem with this star stuff, & with much of the elevator stuff that u read, is that everyone ignores the need to keep the elevator steady, if any rotation or vibration then most bending tests would be hopeless.You quoted Einstein's description. It was a box hanging on a rope that went off into the darkness. The guy could go outside the box and see the rope.
One problem with this star stuff, & with much of the elevator stuff that u read, is that everyone ignores the need to keep the elevator steady, if any rotation or vibration then most bending tests would be hopeless.
We can assume a reasonable lack of vibration and spin. If it spins, the guy can take steps to halt that. He's got a lab after all. Yes, that's what gyros do. You can halt the spin of Earth if you are in possession of a gyro that's up to the task.
Quote from: mad aetherist on 16/12/2018 11:39:00But it is obvious to me that if an elevator is accelerated upwards at g (in zero gravity) then the beam of light crossing the elevator must appear (for an observer in the elevator) to have a bend downwards equal to a ballistic trajectory. Careful of things you find 'obvious', but yes in this case. Ditto for the one sitting on the surface of Earth.The straight-across observation was for the freefall case, both in and not in a gravitational field.
But it is obvious to me that if an elevator is accelerated upwards at g (in zero gravity) then the beam of light crossing the elevator must appear (for an observer in the elevator) to have a bend downwards equal to a ballistic trajectory.
Quote from: mad aetherist on 16/12/2018 12:11:02Therefore the beam will appear to go straight when the elevator is in a gravity field & when not.So says the 'silly' equivalence principle, yes.
Therefore the beam will appear to go straight when the elevator is in a gravity field & when not.
QuoteTo the observer the photon will appear to crab, ie skid sideways. But the photon will in fact be propagating directly ahead in its own frame, ie as if following a simple curved trajectory. So far you have failed to say how this can be measured. If you like, make the gravity and distance large, so the 'crabbing' is significant.
To the observer the photon will appear to crab, ie skid sideways. But the photon will in fact be propagating directly ahead in its own frame, ie as if following a simple curved trajectory.
QuoteSo in theory it might be possible to measure the downwards angle.[/b] However the problem is that the downwards angle of such a photon is certainly much too small to measure -- & in any case i don’t even know of any kind of test that might measure such an angle.It would I suppose help if there was such a thing.
So in theory it might be possible to measure the downwards angle.[/b] However the problem is that the downwards angle of such a photon is certainly much too small to measure -- & in any case i don’t even know of any kind of test that might measure such an angle.
Quote from: mad aetherist on 17/12/2018 01:38:06Quote from: HalcSo says the 'silly' equivalence principle, yes.I think that there are a few 'the' equivalence principles.The primary one is i think the law of the equivalence of inert mass & gravity mass (as per Einstein's chest thort-X).The next one is say the weak equivalence principle, that all things fall at the same speed.The next one is say that all experiments will give the same equivalent result in any-every reference frame.None of those. I means the one that comes up when you google "equivalence principle". The inertial thing is a corollary of it.
Quote from: HalcSo says the 'silly' equivalence principle, yes.I think that there are a few 'the' equivalence principles.The primary one is i think the law of the equivalence of inert mass & gravity mass (as per Einstein's chest thort-X).The next one is say the weak equivalence principle, that all things fall at the same speed.The next one is say that all experiments will give the same equivalent result in any-every reference frame.
So says the 'silly' equivalence principle, yes.
Things do not fall at the same speed, but rather accelerate identically under an identical gravitational field.
Not all experiments yield the same result in different frames.
QuoteModern science seems to have ignored photons. There is little official info re how long or wide etc a photon is or isnt. Are photons dead straight.No, photons are quantum entities and do not have classic properties such as dimensions, straightness, or even location.
Modern science seems to have ignored photons. There is little official info re how long or wide etc a photon is or isnt. Are photons dead straight.
Quote from: mad aetherist on 17/12/2018 01:17:12I do believe in relativity, neo Lorentz relativity, not Einsteinian SR & GR relativity (altho in many cases they give the same answer).In all cases they give the same empirical answer. If they didn't, there would be a falsification test. Your aether theory on the other hand does not.
I do believe in relativity, neo Lorentz relativity, not Einsteinian SR & GR relativity (altho in many cases they give the same answer).
QuoteBut when Brown measures the angle of the two pendulums (wts on threads) then in a gravity field if he uses a measuring rod horizontally then the length of the rod will not be affected by its height from the floor because the rod is being held perpendicularly to the line of action of the field, Einsteinians & aetherists agree.I don't think orientation in a gravitational field has any effect on length of a rod in its own frame.
But when Brown measures the angle of the two pendulums (wts on threads) then in a gravity field if he uses a measuring rod horizontally then the length of the rod will not be affected by its height from the floor because the rod is being held perpendicularly to the line of action of the field, Einsteinians & aetherists agree.
QuoteTo the observer the photon will appear to crab, ie skid sideways. But the photon will in fact be propagating directly ahead in its own frame, ie as if following a simple curved trajectory. So far you have failed to say how this can be measured. If you like, make the gravity and distance large, so the 'crabbing' is significant. QuoteSo in theory it might be possible to measure the downwards angle.[/b] However the problem is that the downwards angle of such a photon is certainly much too small to measure -- & in any case i don’t even know of any kind of test that might measure such an angle.It would I suppose help if there was such a thing.
Quote from: mad aetherist on 16/12/2018 02:34:09the photons coming from the distant star will be pointing exactly along that vizible line, whereas photons coming from an internal source can be crabbing-skidding as they come out (i can explain).You say you can, but you don't. Last I checked, I could not purchase a photon-crab-skidding detector. You need a security clearance to get one.
the photons coming from the distant star will be pointing exactly along that vizible line, whereas photons coming from an internal source can be crabbing-skidding as they come out (i can explain).