Aberration and Ether
"Those are my principles. If you don't like them I have others."
Groucho Marx (1890-1977)
One of the most controversial issues during the ether vs. photon debates of the early 1920s had to do with ether and aberration of starlight.† Because of the null result of the MMI, ether drag had to be considered.† However, since ether drag dragged the light from stars with the earth, it was felt by some that there would be no aberration of starlight if the ether drag theory were true.† This chapter will be somewhat speculative, but between the two theories that will be presented, the truth is likely to be found.
There is almost no doubt that aberration of starlight with the ether drag theory involves the apparent or actual bending of light at the boundary, meaning outside edge, of the ether drag.† Lunar Laser Ranging experiment demonstrate that the ether drag extends many tens of thousands of miles above the earth's surface.† It is at the outside surface or boundary of the ether drag that aberration of starlight must occur.† In fact this theory was mentioned by Stokes as early as 1845.† Stokes theory, viewed today, is more of an explanation of "atmospheric refraction," which will be discussed in the next chapter, but he understood that aberration of starlight did occur at the boundary of the ether drag and continued as the light passed through the ether drag.
There are two basic theories that will be discussed in detail.† Briefly, the first one is that the bending of light at the boundary of the earth's ether drag is an apparent bending, and only appears to bend to those inside of the ether drag.† The second theory is that the bending of light at the boundary of the earth's ether drag is an actual bending of light. †It is also possible that a combination of the two theories is the correct choice.
Moving Medium Laws (an Apparent Bending)
First, we must discuss how big the sun's ether drag is.† Does the sun's ether drag extend beyond the earth's orbit distance from the sun?† Based on Lunar Laser Ranging experiments, considering how high the earth's ether drag must be, the answer is that it is highly probable that the sun's ether drag does extend well beyond our earth's orbit distance from the sun.† This will be assumed in this chapter.
This means that the earth is orbiting the sun inside of the calm ether ocean of the sun's ether drag.† This means that the aberration of starlight at the boundary of the earth's ether drag, is based solely on our earth's orbit velocity around the sun.† This also means that the bending of light for secular aberration (apparent or actual) occurs at the boundary of the sun's ether drag, many millions of miles from the earth.† This means that total aberration occurs in two phases: first at the sun's ether drag boundary for secular aberration, and second, at the earth's ether drag boundary for stellar or annual aberration (actually, the USNO almanac included secular aberration as a part of the definition of stellar aberration, but I am separating them because they probably occur at two different locations).
Whatever causes the bending of light at the boundary of the earth's ether drag is also causing the bending of light at the boundary of the sun's ether drag.† Thus, we will only talk about the earth.† (Note: It is possible that the galaxy also has a type of ether drag, thus the bending of light at the boundary of the sun's ether drag may not be based on our solar system's total velocity in space.)
Let us consider a beam of light from a distant star as it comes into contact with our moving ether drag, I say "moving" because we are orbiting the sun at 30 kps, thus the ether drag is moving relative to a light beam from a distant star.† Suppose the beam enters this ether drag perpendicular to our path around the sun (i.e. to our ecliptic plane) and perpendicular to the earth where we are standing (technically this beam is normal to our horizon plane - the 2D plane tangent to where we are standing).† Let us consider how different observers view this beam of light.
The first observer travels with the beam of light, but he stops and stays stationary just before the beam enters our moving ether drag.† This person waits above our earth and watches the path of the light from directly above the earth until the light hits the earth or passes by the earth.† Even though our ether drag is moving (i.e. our earth is moving), this person may notice that the light travels in a straight line, whether it hits the earth or not.† The beam may, by nature, travel in a straight line (as seen by this first observer) even when it hits a moving medium such as ether drag.
To visualize how this can happen, the "Moving Medium Laws" will now be described.† To understand how they work, do this mental exercise.† Consider a 5 meter tall sphere made of chicken wire (chicken wire is mostly air, the wires are very thin and are very far apart).† Suppose that in the middle of this chicken wire sphere is a soccer ball that is rotating.† Now suppose that the entire interior of this chicken wire sphere (except for the soccer ball) is a chicken wire array or grid.† In other words, every cubic meter of this chicken wire sphere is filled with a 3 dimensional grid of chicken wire.
Now image that this chicken wire sphere is placed on a flatbed car on a train and that the train is traveling at a constant 70 kph.† As this train is entering a tunnel, someone standing on top of the tunnel (this is the person just mentioned that stops before the light gets to the ether drag) drops a single, but large, drop of water straight down at the train.† The release of this drop of water is timed so that it hits the very top of the chicken wire sphere just before the flatbed car enters the tunnel.
This observer standing above the tunnel (who is equivalent to the first observer above), who drops the drop of water, notices that the drop of water travels in a perfectly straight line whether it hits the soccer ball or the flatbed car.
A second observer is standing a hundred meters away from the train; he is standing on the ground.† If this person focuses only on the drop of water, he will observe that the drop of water moves in a straight line until it hits the soccer ball or the train.
However, if this second observer focuses only on which wires inside of the chicken wire sphere are touched by the drop of water, he will notice that a pattern emerges.† A string drawn between the places where the drop of water hits the chicken wire grid forms a straight line that angles in the opposite direction that the train is headed (using the top of the sphere as the beginning reference point).
A third person, sitting on the flatbed car and moving with the train, exactly where the drop of water finally hits the flatbed car, will think that the drop of water is coming down at an angle.† To understand why this is so, note that the string just mentioned represents the path of the water drop relative to the chicken wire grid.† Because this person is moving with the train, she will think that the drop has come down at an angle because she will see the path of the water drop relative to the chicken wire grid.† Since the observer sitting on the flatbed car sees the direction the water drop appears to come from, she would see the water drop coming in at an angle, not from directly above.† In fact, the angle formed by the string would be the exact angle she would see the drop of water coming in from.† The "bend" of the drop of water is both apparent, to those moving with the train, and occurs exactly at the boundary of the chicken wire.† Once inside the chicken wire, the drop travels in a straight line relative to the wire and string, but it travels at an angle.
The third person is equivalent to an astronomer that is inside of the ether drag.† Since the light bends in the opposite direction of the path of the earth (starting from the top of the sphere), it is clear to her that to align her telescope with the light beam that reaches her, she needs to tilt her telescope in the same direction that the earth moves.
With this theory, the tilt of the telescopes is needed because the bending of light is caused by the moving ether drag surrounding our earth, meaning the "moving medium."† The tilt is not due to the motion of the telescope while a photon travels from the top to the bottom of the telescope.† The bending of light starts to occur at the boundary of the ether drag (i.e. at the top of the chicken wire), long before the light gets to the telescope.
Thus there are three observers of this drop of water.† Two of them see it travel in a straight line.† The third observer, who is moving with the train, sees it come in at an angle.† The same phenomenon would occur for aberration of starlight in the Moving Medium Law scenario.
Likewise, if there were a fourth person laying stationary on the train tracks, directly underneath where the water was dropped, because this person is not moving, he would see the drop of water travel in a straight line, meaning directly from above.† I make this note because of occultations, which will now be discussed.
One might wonder if there is any evidence that the Moving Medium Laws might be valid and that the bending of light is only an apparent bend to those inside of the ether drag.† The answer is yes, and as might be expected, it comes from astronomy.† If the earth has ether drag, then so does Jupiter.† Jupiter's ether drag would be much denser than our earth's on its surface and it would have a much higher altitude of ether drag than the earth's.
The light that comes from a star, and passes next to Jupiter on its path to us, must pass through the ether drag of Jupiter.† Thus, we are the "fourth person" mentioned above relative to the train example (i.e. we are underneath the train and are stationary relative to the ether drag of Jupiter).
In astronomy there is a phenomenon called "occultation."† An occultation basically occurs when one celestial body (always a planet, moon, asteroid, etc., but never a star because we don't see stars move very quickly) goes in front of another celestial body.† Usually, it is the moon or a planet that, in its motion, moves in front of a star.† In the case of Jupiter, there are people who have regularly observed occultations that involve Jupiter.
Based on what I know about occultations (which isn't a whole lot), unless there is an atmosphere involved (which will be discussed in the next chapter), the light bends very little, if at all.† This slight bend could be caused by the River Effect Laws (to be discussed below) or the Density of Ether Laws (to be discussed in the next chapter) or something else.† Sorting all of this out will take a considerable amount of time, but for now it is sufficient to state that there are three possible causes of the key types of "aberration," and two of them involve the actual bending of light.
Occultations involving the mountains on the top or the bottom of the moon (from our perspective) can be measured extremely accurately.† These occulations, called "grazes" when the starlight grazes the top or bottom of the moon (as it appears to us), indicate that the Moving Medium Laws are part of the answer to aberration.
Signals That Travels With a Particle Versus Signals Between Two Particles
Suppose there are 1,000 soldiers standing in a perfectly straight row (shoulder to shoulder), and they are standing 3 meters apart from each other.† Now suppose there are a thousand rows of such soldiers, where there is 3 meters between rows.† Now suppose all 1,000,000 soldiers start to march slowly across a large field in perfect formation.
As they are marching, a person tosses a ball to one of the soldiers on the outside column of the formation.† This soldier instantaneously passes the ball to the soldier next to him, at the exact same speed that the soldiers are marching.† In other words, the soldier only has the ball in his hands for a nanosecond, but throws the ball to the position of the solder next to him (in the same row) at the instant he received the ball.† However, because the velocity of the ball is equal to the velocity of the marching soldiers, the ball would be caught by the soldier behind the solder standing next to him.† In other words, while the ball is "in the air," the soldier standing next to him moves 3 meters forward, leaving his position vacant, and the soldier standing behind this solder moves into the vacant position of the soldier in front of him and catches the ball when it gets to him.
Now let us consider the person that originally threw the ball to the first soldier.† As the ball is passed from soldier to soldier, during the march, the person that originally threw the ball would see the ball travel perpendicular to the direction the soldiers are marching.† In other words, just like the person above the train in the previous example saw the water drop travel in a straight line, perpendicular to the road he is standing on, the person that threw the ball would see the ball travel in a straight line perpendicular to the vector of the marching soldiers.
Note that in this example, each soldier holds onto the ball for only one nanosecond, but the ball is passed to the next soldier (actually the person behind the next soldier), very slowly.
If we looked from above, and drew a line connecting all of the soldiers that touched the ball, this line would form a 45 degree angle relative to the vector of the marching soldiers, terminating at the soldier that first touched the ball.† If we looked from above, and focused on the ball itself, it would move perpendicularly from the person that threw the ball.
Now let us change things.
Now let us suppose that each time a soldier receives the ball, he holds onto it while he marches for 3 meters, then he instantaneously (at the speed of light) passes it to the person standing next to him.† In this case, the person marching next to him would be the one that catches the ball.† Everyone that touches the ball would be in the same row.
If we looked from above in this case, and drew a line connecting all of the soldiers that touched the ball, this line would be one row of soldiers.† However, the person that originally threw the ball would see the ball travel at a 45 degree angle to his right (assuming the soldiers were marching to his right).
In the first case, the ball was only instantaneously touching the soldiers, and slowly moved between the soldiers.† In the second case, the ball was held on to by the soldiers, but was instantaneously passed to the person next to him.† The pattern seen by those standing above the marching soldiers (i.e. a string connecting the soldiers that touched the ball) was different for the two cases.† Likewise, it was different for the person that originally threw the ball.
If these soldiers represented ether particles, and if the ball represented an electromagnetic wave, which of the two examples best explains the moving ether drag as light enters the ether drag?† The first case was the one already mentioned, which was represented by the chicken wire and train.† In the first case, the chicken wire did not "carry" the drop of water with it, it simply "passed it on" instantaneously to the "next" wire that happened to touch it.
The second case will now be mentioned.
The River Effect Laws (an Actual Bending)
The key element of the "River Effect" laws is the path of light entering the moving medium of ether drag, but in this case the assumptions are different.† In this case, the light is carried with the ethons, and is instantaneously passed to the next ethon.† The reader should pay close attention to any discussion of the "path" of sound in water.† The term "River Effect" originates from a visualization of the path of sound in a river.
Let us for a moment consider a large, square swimming pool which is 10,000 feet across, side-to-side, and 100 feet deep.† Let us put a bell, or some other device for making sounds, 50 feet below the surface in the middle of the swimming pool.† Let us further put a device on two opposite sides of the pool (each halfway from the corners of the pool and across from each other), also 50 feet below the surface, which can not only detect sound intensities, but can also determine the direction the sound comes from.
If we ring the bell, based on the speed of sound in water, a certain amount of time will elapse between the ringing of the bell and when the listening devices on opposite sides can detect the sound.† Let us measure this amount of time.† This time is assumed to be the same time whether we were in a lake or a swimming pool.
Now let us change the scenario.† Let us find a river which is 10,000 feet wide and which is 100 feet deep.† Let us again put a bell 50 feet below the surface in the center of the river.† Let us also put two listening devices, directly across from each other, such that the bell is half way between them (note: the bell and each listening device is 5,000 feet apart from each other).† Each listening device is 50 feet below the surface.† The line between the listening devices not only includes the bell, but is obviously perpendicular to the flow of the river.† Further, let us assume that the water in this river travels from left to right, from the observer's perspective, at a speed of 150 miles per hour (a very fast river to be sure).† The observer is standing next the bell on his side of the river.
Let us consider an imaginary circle around the bell, and consider that the shore is tangent to the circle (i.e. the radius of the circle is 5,000 feet).† Since the bell is in the center of the circle, we can consider 360 different sound vectors leaving the bell, one for each degree of the circle.
One of these 360 sound vectors initially heads directly towards the bell at the opposite side of the river from the observer.† While sound will reach this bell, the sound vector that initially heads towards this bell will not reach the listening device because the river will carry the sound downstream at 150 miles per hour.† In other words, as the molecules of water bump each other, the water will simultaneously carry these molecules and the sound signal downstream.† Since the water molecules physically bump each other, the scenario is somewhat similar to the second scenario with the marching soldiers, meaning the "time" the signal takes to travel between soldiers is virtually zero (because the molecules are bumping each other).† After each molecule is bumped by a neighbor molecule, as it is traveling to bump the next molecule it is also traveling downstream.
Now consider the sound vector that actually did arrive at the listening device on the opposite shore.† This sound vector initially headed upstream from the line perpendicular to the two listening devices.† If a person could track the path of this sound vector, it would be seen that the path of this sound would travel in an arc, where the sound initially heads upstream from the listening device, then arcs and eventually heads downstream to where the listening device is located.
I have stated that sound travels in an arc in this situation; this statement needs to be clarified.† Sound travels in water by water molecules bumping each other.† Thus, if the water (i.e. the medium) is in motion, the water molecules are in motion, and the motion of the water molecules will effect the path that the sound travels, since sound travels solely because of the water.† Since the initial direction of this sound vector is upstream from the direction of the water, this sound vector will arc.† Actually it will arc until its tangent becomes perpendicular to the motion of the water and then it will move in a straight line downstream (at the same angle the sound vector did that was initially headed towards the bell).
When a bell is rung, sound actually travels in all directions simultaneously.† Thus literally 360 different paths of sound could be theoretically followed after one ringing of the bell.† To plot the path of each of these 360 sound vectors would yield what I call the "River Effect Chart."† It would be a combination of straight lines, curved lines, and lines that are at first curved and then go straight, as I will now expand on.
If a person could track the sound that initially heads in a straight line towards the listening device on the opposite side of the observer, that sound would travel in a straight line, but the straight line would head downstream from the listing device.† This sound would not reach the listening device on the opposite side.
The sound vectors that initially head upstream and eventually reach the shore, however, do not travel in a straight line.† The path of these sound vectors is an actual arc, regardless of where this sound reaches the other shore!† This is because the sound is headed upstream originally, but the motion of the water carries it backwards as it travels.† The arc may be very pronounced or be very flat, depending on:
1) The angle at which the vector heads upstream (i.e. the angle relative to a line which is perpendicular to the direction of the water), and
2) The relationship between the speed of sound and the speed of the water, and
3) The distance the sound has to travel.
Furthermore, for some of the upstream vector angles the arc may become a straight line before reaching the other shore. †Once a line tangent to the arc becomes perpendicular to the direction of the flow of the river the sound vector will turn into a straight line from then on.† Thus it may be an arc for only part of the time.† However, the beginning point where it becomes a straight line is upstream from the direct line between the bell and listening devices.
Likewise, for some of the vectors that travel directly upstream, or nearly directly upstream (meaning nearly parallel with the flow of the water), these vectors will never reach the shore at all.† They will theoretically come back, but will dissipate long before they come back to the bell, from where they came.
If this experiment were actually to be performed (actually such an experiment would be virtually impossible to perform unless a "sound laser" could be invented that shot out a very narrow sound wave), two things of significance would be learned.
First, for the sound vector that actually hits the listening device on the opposite side; the time that it takes the sound to reach the listening device will be longer than it took in the swimming pool (this is because of its path).
Secondly, for this same sound vector, the portion of the listening device which determines the direction the sound is coming from will falsely determine that the sound is coming from a point upstream from where the bell is actually located.
Now consider anyone standing on the far shore.† If they could see the sound vector that initially heads for them, they would realize that this not the sound vector that arrives where they are standing.
It is of critical importance to note here that the medium is in motion.† If the medium is stationary, and the bell is in motion, it is highly probable that all sound lines emanating from the bell will be straight lines.† It is important to keep in mind whether it is the medium or it is the bell that is in motion!† It is also important to keep in mind whether the measuring of the sound is taken by someone who is in motion in the water or who is standing on the shore.
With ether drag, if the River Effect Law solely causes aberration, it is an actual bending of light, and it occurs at the boundary of the moving ether drag.
Back to Aberration
Is aberration of starlight caused by the Moving Medium Laws or the River Effect Laws, or some combination of the two?
First, the reader should be reminded that the Moving Medium Laws create an apparent bending of light only to those inside of the ether drag.† The River Effect Laws creates an actual bending of light, to everyone, whether inside the ether drag or not.† Because occultations of Jupiter seem to indicate that starlight is not actually bent by a moving ether drag (or is bent very little), this experiment indicates that the Moving Medium Laws are the only laws, or are the dominant laws, affecting aberration.† However, since no one has specifically looked at a Jupiter occultation with this question in mind, with extremely accurate measuring instruments and formulas, occultations cannot be considered a definitive proof of the Moving Medium Laws.
The point to this discussion is this, in the Moving Medium Laws the aberration of starlight would occur at the boundary of the ether drag.† With the River Effect Law, if the starlight was headed downstream of the motion of our ether drag, the aberration of starlight would also occur at the boundary of the ether drag.† To understand why, consider that when a sound vector comes from the bell, the angle of the vector is determined immediately after the bell is rung, not when the vector is halfway to the opposites shore.† With the River Effect Laws, if the starlight was headed upstream from the motion of our ether drag, the ratio of the speed of light and the velocity of our planet in orbit around the sun (remember the sun's ether drag is assumed to extend beyond our earth's orbit distance), is so dramatic, that it is unlikely that the light would arc significantly (i.e. it would be unmeasurable).† Thus, even in this case the aberration of starlight would occur at the boundary of our ether drag.† Thus, any aberration of starlight caused by the combination of the two laws would also be at the boundary of the ether drag.
Sir George Airy Water-Telescope Experiment
Sir George Airy, in 1871, built a water-telescope to prove the ether theory.† Because it was believed that aberration occurred inside the telescope (ether drag was known about, but was not generally believed at the time of his experiment), and because the speed of light is slower in water than in air, Airy expected that the aberration of light in a normal air-filled telescope would be different than the aberration of light in a water-filled telescope.† In other words, refraction of light, when the starlight hit the boundary of the water in the telescope, would be different than normal aberration would predict.† It did not happen - he got a null result, meaning the aberration of light was the same for both air-filled (as all telescopes are by default) and water-filled telescopes.
This null result is typically explained by ether proponents by using the Fizeau Drag Coefficient.† However, the Fizeau Drag Coefficient is designed for use where there is ether, but no ether drag.† During the time of the Airy experiment, ether drag had long been speculated, but it was not the commonly accepted theory for ether, as is evidenced by the surprise of the MMI null result.
In fact, what the Airy experiment proves is that the aberration of light occurs before the light gets to the telescope.† Airy was looking at stars directly above him, thus the angle at which the light is coming in is so small that the refraction of this light as it hits the boundary of the air and water would be negligible.† Nevertheless, a modern day Airy experiment, done with the telescope pointing straight up, as his was, and done with far more accuracy than the original, would be a good test for whether aberration of starlight in ether drag occurs at the boundary of the ether drag.
The concept of ether drag does not depend on the Moving Medium Laws or the River Effect Laws, but it is fairly apparent that stellar aberration does occur at the boundary of the ether drag.
It was also well known in the late 1800s that the Fizeau Drag Coefficient was not needed for terrestrial light sources.† This should have been a clue that ether drag was indeed the preferred theory of ether, but obviously it did not catch on at the time.
Secular Aberration and Ether Drag
The above discussion explains the observable 30 kps stellar aberration of starlight.† How about the 370 kps secular aberration of starlight?
If the sun's ether drag does not extend to the orbit distance of the earth around the sun, then the aberration that occurs at the edge of the earth's ether drag must be at the total 340 to 400 kps velocity of our earth in the cosmos.† The differential aberration, caused exclusively by our orbit around the sun, would be observable, but the 370 kps of secular aberration would not be noticeable because it is constant.
However, it is much more likely that the suns ether drag extends far beyond the orbit of our earth around the sun.† Consider this logical sequence:
1) The sun's ether drag extends far beyond the orbit of our earth, and
2) The sun's ether drag is moving at 370 kps in the cosmos towards Leo, and
3) When light from outside of our sun's ether drag hits this moving ether drag, by the Moving Medium Laws (and/or River Effect Laws) the light bends (apparent or actual) at the boundary of the sun's ether drag as a function of the speed of the sun's ether drag (i.e. 370 kps) (note that because we are inside of the sun's ether drag we see the light bending with either law), however,
4) Because of the almost linear motion of our solar system, starlight consistently bends in the same direction day after day and year after year and century after century,
5) In other words, the major bending of this light occurs many millions of miles away and has been bending in the same direction for many thousands of years, long before telescopes were invented and long before they were first calibrated, and
6) Because the sun is moving in such a straight line, and for a few other reasons, the same calibration of our telescope will work for a long time (i.e. we don't have to continually adjust our telescopes for this bending),
7) Only the bending of light that is due to the orbit speed of our earth around the sun (i.e. when the starlight hits our earth's ether drag), can be detected because it forces the constant recalibration of telescopes.
In other words, ether drag can easily explain account for the entire 340 to 400 kps variable velocity of our earth towards Leo.
For planets and the moon and other objects that are inside of our sunís ether drag, their light travels within the sunís ether drag and thus because we are also within the sunís ether drag, our telescopes do not need to be tiled for secular aberration.† For planets that are outside of the sunís ether drag, the bending would occur many millions of miles away and the bend would be consistent (for a given location of the planet), thus celestial mechanics formulas would be calibrated for their apparent location, which would include secular aberration (all of this ignores galactic ether drag).† Because the pattern of ether drag in the galaxy is a matter of pure speculation I will not pursue this issue.
Thus, aberration of "starlight" for Mercury (assuming we knew where it actually was), would be different than aberration of "starlight" for Jupiter (assume we knew where it was and assuming the sun's ether drag did not extend that far).
In 1923-1924, during the short ether-photon debate, it was believed that our earth's only motion in space was a closed elliptical orbit around the sun.† Thus annual aberration of starlight, which was also based on a closed elliptical orbit, was considered proof of the photon theory of light.
But our earth's average speed is now known to be 370 kps and our net direction is nearly linear.† But yet annual aberration of starlight is still based on an average speed of only 30 kps and the tilt of telescopes is still based on a closed elliptical orbit!
Indeed, even though all of this can be easily explained, when the discovery of CMBR was made, the ether-photon debate should have been reopened, but it wasn't.