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Thanks for answering guys, pleased to meet you! Hi Mathew, do you mean that, to your opinion, light is not bent by gravitation?
Hi Mathew, do you mean that, to your opinion, light is not bent by gravitation?
....you will see that the two light rays travel in the same direction once they start traveling nearby together at the sun's perimeter. Being independent from the body where they come from at this point in space and time, do you see any reason why they should experiment a different bending?
in my opinion, based on experimental evidence, gravity has no effect on electromagnetic waves
The light rays you show in your diagram would be affected differently because they spend different amounts of time in the gravity field.
However, in principle it is possible to imagine 2 rays that do end up parallel but there are some issues to consider. On the sun the effect is exceedingly small
if you use a neutron star as your example it is much easier to consider that your diagram would be correct
... Anybody thinks that the rays coming from the sun should also be curved by the gravitation of the sun?
One minor problem with this argument is that it assumes that a photon emitted near the limb of the solar disk could reliably reach the Earth. The light is emitted from the visible disk of the Sun because the temperature of the Sun is sufficiently high; but at these temperatures, the Sun's atmosphere is effectively opaque to visible light.
As an example, a neutron star would be more difficult to imagine than the sun, because it doesn't produce visible light and because it has no measurable diameter.
Quote from: Le RepteuxAs an example, a neutron star would be more difficult to imagine than the sun, because it doesn't produce visible light and because it has no measurable diameter.I think that this latter comment was referring to a black hole, rather than a neutron star.A http://en.wikipedia.org/wiki/Neutron_star#Structure [Links inactive - To make links active and clickable, login or click here to register] has a definite surface, and a very compressed atmosphere (perhaps μm thick).They are very hot (at least initially), and will produce visible light as well as X-Rays.
Sun will appear very slightly bigger because of gravitational-lensing ...https://van.physics.illinois.edu/QA/listing.php?id=21717&t=gravitational-lensing-of-the-sun [Links inactive - To make links active and clickable, login or click here to register]
Light refraction of plasma medium is a conventionally accepted physical phenomena...Example: http://journals.aps.org/pr/abstract/10.1103/PhysRev.162.117 [Links inactive - To make links active and clickable, login or click here to register]Or, is the San disobeying the low of refraction?
Light refraction of plasma medium is a conventionally accepted physical phenomena...
The way I understand it, gravitation from the sun during an eclipse is affecting the position of all the stars that we observe at that moment, which means that most of them appear far away from the sun's perimeter, so that their light doesn't have to go through the sun's atmosphere to be bent. If it is so, then refraction wouldn't affect those rays, so how would you explain their bending?
...the refractive index of a plasma is frequency dependent, but observations show the bending to be frequency independent.
Good observation Collin!
You mean that you observed a refraction phenomenon when the source was near the sun? That some of the frequencies vanished?
Rainbow effect is internal to planets atmosphere just like we see at sunset...
And what about my proposition that the rays might get curved the same way aberration curves them, but by the acceleration of the earth towards the sun instead of its inertial motion around it?
To better understand what I mean by that, you may refer to my thread on inertial motion:http://www.thenakedscientists.com/forum/index.php?topic=53171.msg467891#msg467891
Interesting idea though.
However, I think you'll find that the rays should be bent towards the center, but the effect is so small that they still reach us here on earth causing the sun to appear infinitesimally larger.
I think I found a way to test my point!If the sun's light was really curved by its own gravity, it follows that a spiral galaxy light would also be, which means that its apparent diameter would also look larger than it really is. In the case of galaxies, the measure of their rotational speed made at different heights would thus be attributed to larger heights than the real ones, which could explain the lack of gravitational pull that we attribute to Black Matter. Anybody wants to help me with the maths?
let's work out an example and see if this is even feasible. We'll assume a galaxy 100,000 light years across with a mass of 100,000,000,000 solar masses which is 1 billion light years away.The light from a source behind this galaxy and just skimming its edge, would by gravitational lensing be deflected by 0.258 sec of arc. Since 1/2 of this deflection occurs on the inbound path, the most we can expect light coming from a star at the edge to be bent on its outward path to us is 0.129 sec of arc.At a distance of 1 billion light years, this equates to an apparent displacement of ~625 light years ( meaning the galaxy would appear to be 50,625 light years in radius instead of 50,000.)Calculating the difference in orbital speed at 50,000 vs. 50625 light years produces orbital velocities of 167 km/sec vs. 168 km/sec.If we work out how much extra mass it would take to make that 1 km/sec difference at a fixed radius of 50625 light years, it works out to a difference of ~1.2%, or far short of the amount of dark matter needed to make up for the missing mass according to the actual orbital velocities we measure.In addition, gravitational lensing in fact gives us additional evidence for dark matter. Because of the extra mass due to DM, the light passing galaxies bends more than and differently from what we would expect from just the matter we see.On top of that, we have the case of the Bullet Cluster, in which dark matter has been "knocked loose" from the visible matter in a collision between galaxy clusters. In this situation we see gravitational lensing of objects behind the cluster where there is no visible matter to cause it.Galaxy rotation curves may have set us on the road to dark matter, but there has been a great deal of other supporting evidence uncovered since the first step on that path.
Yes, in my opinion, based on experimental evidence, gravity has no effect on electromagnetic waves, photons, magnetic fields and electric fields...But it does affect the frequency of all oscillating structures including pendulum and atomic clocks...
Quote from: mathew_orman on 28/09/2015 08:16:12Yes, in my opinion, based on experimental evidence, gravity has no effect on electromagnetic waves, photons, magnetic fields and electric fields...But it does affect the frequency of all oscillating structures including pendulum and atomic clocks...What? Electromagnetic waves ARE an oscillation. A photon is comprised of an electric component and a magnetic component, both of which oscillate. Magnetic and electric fields are actually comprised of photons.
If we accelerate a first atom which is part of a two atoms' molecule, it necessarily moves before the information from that acceleration has the time to reach the second atom, so the distance between them contracts, and if we are still accelerating that first atom while the information from the motion of the second atom is back, that information will simply pull the first atom forward a bit while it accelerates, so the distance between the two atoms will contract a bit more than previously, and it will go on contracting more and more until the acceleration ceases. At that moment, the information about the speed of the two atoms will be contained between them in the form of doppler effect: the rear atom will perceive redshift from the front one, which will pull it forward, and the front one will perceive blueshift from the rear one, which will push it forward. Contrary to my original small steps, during the motion of the molecule, the two time shifted motions of the atoms would thus happen at the same time, but those motions would still be due to the accumulated doppler effect between the two accelerated atoms. Here is the diagram and the explanations that come with it:We have two atoms A and B that are part of the same molecule. The time interval represents the time the information takes between the two atoms at t0. I did not account for the time dilation of particle A since it moves before particle B, but I think we should. We accelerate A for a while and observe what happens to the system from t0 to t7. The blue arrows represent the blueshifted information that travels from A to B, and the red arrows represent the redshifted information that travels from B to A. The acceleration of A begins at t0 and ends at t4, so because of the time gap, the acceleration of B begins at t1 and ends at t5. After t5, the two atoms travel at the same speed, but we can easily see that the distance between them has contracted, and we can follow its progression during the acceleration. At that moment, the information on the future speed of each atom with regard to aether is situated between them in the form of doppler effect. The main idea is that, without doppler effect, there would be no motion between bonded particles, so there would be no motion either at our scale. I insist on the fact that we have to exert a force to introduce that doppler effect between them, and that this force represents mass. So with the same principle, we explain mass, motion and contraction.
Of course, that arm will move towards the other atom before the information from that motion has the time to move that atom away, so the distance between the arm and the third atom will contract, but the information also takes time between the atoms that form the vertical arm, and if we accelerate its two atoms at the same time, because of the beaming phenomenon, the light from the accelerated atoms would be sent towards the position they would have if the acceleration would immediately stop, so only the light that would be sent at the end of the acceleration would point in the direction of the other atom, which means that this arm would also lose its synchronism during acceleration, which means that Ivanhov might be right about http://www.rhythmodynamics.com/rd_2007en.htm#2.05 [Links inactive - To make links active and clickable, login or click here to register], a data that he obtained with sound exchanged between two emitters, and with winds of different speeds and from different directions. The information that tells the atoms how to move would then be conserved in the form of aberration between them, and it would also belong to their standing wave. This way, after acceleration would have stopped, a signal sent from the middle atom to the two other atoms would take the same time to do the roundtrip because light would already be synchronized both ways with regard to the same middle atom.
Hi everybody,Here is a drawing representing two light rays curved by the sun's mass: a blue ray coming from a star that brushes past the sun, and a red ray coming from the periphery of the sun itself.The two rays are parallel when they begin to travel together at the sun's periphery (dotted red and blue arrows), and they thus hit the earth later at the same angle since, being very close to one another, they almost suffer the same curvature (plain red and blue arrows), what gives to the earth observers the impression that both rays come from the same spot in the sky (dotted red and blue lines that lead to the dotted star).Einstein predicted that the ray coming from the star would get curved by the presence of the sun, but without noticing that the ray from the periphery of the sun itself should also get curved, so he did not realize either that the sun would look wider during this observation, and that he thus would have to shrink it on the mapping of the sky made when the sun was not there to curve the rays.If he had shrunk his sun on the mapping made when the sun was on the other side of the earth, it would have hidden the same stars than the ones that were hidden during the eclipse, so he could not have concluded that light was effectively curved by gravitation as he had predicted, but instead, that the sun's presence was affecting the direction of the rays in such a way that a mapping made in it's presence kind of widened the sky compared with the one made when it wasn't there.Notice that this reasoning does not contradict the observations, it only contradicts the explanation of the observations, reason why I placed it on a science forum, but if it's right, then there must be another explanation, and I did not find it yet, except that gravitation kind of widens the sky when our observations are made from a much less massive body than the one we are gravitating around, which means that it could be the real acceleration of the earth observers towards the sun at the microscopic level that would affect the direction of the rays. So far so good, but as I said, it doesn't seem to work, because moving at an angle through a light ray should bend it in the direction of the movement as for the aberration of star light, which would shrink the sky during an eclipse instead of widening it as the observations show, so I am still looking for an explanation.Anybody finds the idea interesting? Anybody thinks that the rays coming from the sun should also be curved by the gravitation of the sun?
The earth has no acceleration, neither has any other planet, galaxy etc. So I'm not sure what you're thinking of in the MM experiment. That was a setup to measure a presumed aether wind. And light doesn't accelerate, it's more of a state than a speed.
I'm actually studying inertial acceleration, the one a ball suffers when we throw it, not gravitational one.