Did Newton need the electromagnetic wave to postulate the Aether?
374885
The answer is no. Isaac Newton had assumed that light was made up of numerous small particles, in order to explain features such as its ability to travel in straight lines and reflect off surfaces. This theory was known to have its problems; although it explained reflection well, its explanation of refraction and diffraction was less pleasing. In order to explain refraction, in fact, Newton's Opticks (1704) postulated an "Aethereal Medium" transmitting vibrations faster than light, by which light (when overtaken) is put into "Fits of easy Reflexion and easy Transmission" (causing refraction and diffraction). Newton believed that these vibrations were related to things like heat radiation, saying:\n\nIs not the Heat of the warm Room convey'd through the Vacuum by the Vibrations of a much subtiler Medium than Air, which after the Air was drawn out remained in the Vacuum? And is not this Medium the same with that Medium by which Light is refracted and reflected, and by whose Vibrations Light communicates Heat to Bodies, and is put into Fits of easy Reflexion and easy Transmission? \nThe modern understanding, of course, is that heat radiation is light, but Newton considered them two different phenomena (believing heat vibrations to be excited "when a Ray of Light falls upon the Surface of any pellucid Body"). He wrote that "I do not know what this Aether is", but that if it consists of particles then they must be "exceedingly smaller than those of Air, or even than those of Light: The exceeding smallness of its Particles may contribute to the greatness of the force by which those Particles may recede from one another, and thereby make that Medium exceedingly more rare and elastick than Air, and by consequence exceedingly less able to resist the motions of Projectiles, and exceedingly more able to press upon gross Bodies, by endeavoring to expand itself."
255268
Newton believed that gravity acted instantaneously on objects whereas Einstein believed it acted at the speed of light on an object. For instance, if the sun were to disappear suddenly, Newton would predict that all the planets would fly off in straight line paths instantly, whereas Einstein would have predicted that there would have been a lag time for the planets to fly off because nothing can travel faster than the speed of light; including gravity.
1091127
It is reputed to have been Lord Kelvin.  The Michelson-Morley experiment (to find the true reference frame of the universe - the failure of which led to Einstein's discovery of special relativity) and the solution to the blackbody radiation equation (which led to the "ultraviolet catastrophe" and Planck's discovery of quantum mechanics) was all that was left, other than extending the constants to additional decimal places.\n\nHowever, Feynman claims this is more myth than fact.
1110551
The term "Aether" in the context of the Michelson-Morley experiment actually means "preferred reference frame of the universe" - it was thought that light if the earth were traveling with some speed (call it v) with respect to the preferred reference frame, then the light would actually travel through the preferred reference frame with a speed c + v. \n\nMichelson-Morley demonstrated that there is no preferred reference frame - no "aether" so to speak.\n\n"Aether" in that context is a fixed "background" of the universe against which the earth, sun, stars, etc. were all thought to be moving. Whether or not "aether" consisted of something was not important to the Michelson-Morley experiment. Certainly for our small minds it is easier to think of a preferred reference frame as a substance or medium that the earth, sun, stars, etc. were moving through, but it was not necessary for the purposes of the experiment.
694010
If the laws of physics have the same forms in all frames of reference than the cause of interaction is confirmed.\nIn the case of this question there must have  been someone who caused  this fine question.\nOther wise it would have never existed.
289487
I think Isaac Newton might have been as good, considering the limitations of his own time. Just remember he had to develop a new whole math to support his theories! (calculus) Then I dunno, but today Stephen Hawking? Have you read a brief history of time and the universe in a nutshell? I dunno, really, Einstein was GREAT!
239262
For the aether to exist, it must have specific properties that differentiate it from other substances, right?  What are its properties?  Are they different from say a pure vacuum in space?  The experiment was a clever way to demonstrate that the earth does not move through the aether with the kind of doppler effect exhibited by a train through air, but still needed careful evaluation.  For example, the earth moves rapidly around the sun while moving even faster around the core of the galaxy.  Could the earth flatten in the net direction of motion causing at least some confusion in the experimental observations that delt with the speed of light and the length of path in various directions?  There can be many explanations for an observation, but which is best and most consistent with everything else we know let alone suspect?
375243
1) Assuming there are no strong EM fields near the magnet, it should behave exactly as a similar object would due to gravity. The gravitational field of the earth is too weak to produce a measurable effect for this experiment.\n\n2) You need a very long liquid filled container with a speaker on one side and a microphone on the other. Then using a computer to produce and receive the sounds, measure the time taken for the sound to traverse the distance. For accurate results the water needs be still.
103856
Newton' and Einstein's on relativity
975209
Maxwell combined with Einstein showed that the forces associated with elecricity and with magnetism are really the same. THis is because a moving charged particle creates magnetism, but if the particle is moving is based upon your reference frame (you can be moving with the particle and you wouldn't think it was moving). \n\nLight is an electric and magnetic wave and they are always perpendicular to each other... it looks like this: http://www.geo.mtu.edu/rs/back/spectrum/e_mag.gif\n\nA photon is when this wave acts like a particle, and the force that this particle carries is electricity and magnetism (electromagnetic force).
558464
In brief: in Newton's physics, space and time are taught of as frameworks independent from the observer, and the gravity is a force. This means that, whoever observes a certain phenomenon, it has a given and fixed duration and a given and fixed size in space.\n\nIn Einstein's physics, space and time are entangled into the so-called spacetime and their measurements depend on the observer; moreover, the gravity is a distortion of the spacetime. Different observers will report different spacetime measurements for the same phenomenon and different geometrical properties of the same objects in different gravity fields.\n\nEinstein's physics, in principle, replaces Newton's physics completely, as it gives more accurate predictions with respect to experiments. However, the difference between the two is negligible at ordinary speed and gravity forces. Being Newton's physics mathematically much simpler, people prefer using it as long as they can, reserving the application of Relativity mainly to astrophysics and particle physics, where the differences are significant.
827901
There were others including Galileo that Einstein used to help explain how his own theory was developed. These were used by others to try and explain the final results of the famous work by Michelson and Morley which proved that there was no ether. Fitzgerald from Ireland was his greatest contributor as well as Lorentz to the ultimate development of his own theory.
572099
The electric field and the magnetic field are perpendicular to each other.  They are also both perpendicular to the direction in which the wave is traveling.  So picture it like this:  If the electromagnetic wave is going East, then the magnetic field would be going South/North, and the Electric Field would be going Up/Down.  \n\nThat's a very simplified illustration, but it's the basic concept.
13615
Great question.\n\nYou're looking for something physical, but nothing physically warps.  As you said, there's no aether or medium.\n\nThe "warping" is kind of a metaphor for what happens in a mathematical model.  They talk about that and the rubber mat to help people visualize something that's really difficult to grasp, or even believe.\n\nWe've all learned from Newton that an object in motion will continue moving in the same direction and speed unless acted upon by another force.  Well, you can describe gravity as an outside force, as Newton did, and that's pretty easy to understand.  A comet comes flying by the Earth, but the Earth's gravity continually pulls on the comet, and changes its course.\n\nGeneral Relativity takes a different approach to describing the effect of gravity.  It says that gravity isn't a force.  In its version of reality, the comet keeps moving in a perfectly straight line.  Except that a mass can bend the lines.  Yeah.  No aether or medium.  But straight lines are bending.  It's a model to describe how gravity has the effect it has.\n\nWhy do scientists buy into this?  Well, experiment has shown that gravity bends light, and our current understanding of light says that light has no mass.  So the old model of gravity, which acts only on mass, can't explain this.
61320
Michaelson and Morely did some experiments to try to see if the speed of light incipient on the earth was different for light coming from different directions.  Th idea was that if light travels in waves (as it seems to in many regards), then these waves needed to travel through a medium (like when sound waves travel through the air).  This medium was termed "the ethereal ether" and was thought to pervade space, including places with a vacuum; light was thought to be a wave travelling through it.  So Michaelson and Morely decided to try to see our speed relative to the ether by using somthing called an interfereometer.  This compared the speed of lightcoming from different directions.  The idea was that a star we are headed towards should reveal a higher speed of light, while ones we're rushing away from should have a lower speed, due to the Doppler effect.  What they found was that the speed was the same in all directions, meaning that if there was an ether, then we we perfectly at rest relative to the ether.\n\nThen mathematicians and physicists looked at the theories of Scottish physicist James Clerk Maxwell.  Maxwell had taken all existing theories on electricity and megnetism and unified them into a single, cohesive set of equations.  These equations showed how electricity could create a magnetic field, and a magnetic field could induce an electric current.  This could happen in such a manner that an electric field would induce a magentic field, which in turn induced an electric field, which in turn induced a magnetic field, and so on.  The equations made it clear that this wave would travel at a certain specific speed.  Incidentally, that speed was similar to the speed of light measured by French scientist Fizeau in 1849 (several decades earlier) and confirmed by Foucault.\n\nIt was all of this that led Einstein to formulate his special theory of relativity.  Since light moved as an electromagnetic wave, and since those waves had a speed that was predicted directly by Maxwells equations and was independent of the velocity of the observer, Einstein came to recognize that simultaneity was not a universal concept, and that time changed with velocity.  The idea of the ether was discarded as needless baggage.
1139045
They are not pseudo scientists. It was the Michelson/Morley experiment's result. \n\nSince Ether theory was scientifically accepted at the time, The object of the experiment was to measure the speed of light with the assumption that light travels through a medium called ether.\n\nWhen the experiment failed, Michelson and Morley thought that the equipment they built was not sensitive enough to see the phase change of the reflected light that can be used to calculate the speed.\n\nThey were not aware that their experiment was a big discovery in science that disprove the presence of ether in space.
375132
Newton's optics was based on light particles (photons). He could not have know about interference since no source of coherent light existed at the time for him to experiment with.