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ELECTRICITY, MAGNETISM, and LIGHT

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There's clearly a link between: electricity, magnetism, and light.

Part of the energetic system of an atom, are one or more electrons, but one electron can be on its own also. A stream of electrons are called an electric current and the whole electric thing together is called electricity. When an electric current flows, it creates a magnetic field. This is easy to prove with a compass (that contains a permanent magnet) and is an important part of every day technology.
As long as the current flows, there is a electro-magnetic field. Less people know that it costs energy to create a magnetic field, and that when turning of the power, the field collapses and produces power.
Another way of everyday is moving permanent magnets near a coil (a wound-up metal wire) to produce an electric current.
So; the link between electrons and magnetism is very clear.

And light. Light on a solar panel produces an electric current, and an electric current on a LED (light emitting diode) produces.. light. So these are clearly linked too.

How about light and magnetism?

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But how about their link to gravity? Everything in this universe is part of this universe thus linked somehow, but how in this case?

Maybe we haven't found the link yet because we didn't look precisely enough. To create a gravitational force of 1G, one needs a mass as large as the Earth. But to overcome that force on something weighting 1KG, just a thin string of wire is enough. The forces that keep molecules together is so much stronger than gravity.

A brief summery of history

1687
Sir Isacc Newton published his "Principia Mathematica" that described "the fundamentals of nature" being: time, space, and motion. The equations by which the motion of planets could be predicted in their orbits through the solar system. His view on universe was a fixed and stable one. Space was unbending and unyielding, and time was equally absolute, ticking away at the same rate for everyone, everywhere in the Universe. It didn't cover electricity and magnetism though, and although it described gravity really well, he (and everybody else) didn't know what gravity actually was.

1750’s
Benjamin Franklin experimented with electricity, flying his kite into an electrical storm to capture the disccharge from a bolt of lightning.

1820's
Hans Christian Oersted noticed in that a compass needle would be deflected whenever it was held in close proximity to an electrified wire.

1831
Michael Faraday demonstrated the reverse of Oersted’s discovery; he demonstrated the principal of induction, in which a magnet would produce electrical current in a wire.

1860's
James Clerk Maxwell determined that electricity and magnetism were manifestations of a single fundamental natural force called “electromagnetism”. He produced a set of equations, defining the relationship between electricity and magnetism. He also proposed that waves of electromagnetic energy could travel through space at the speed of light, and that light is a form of electromagnetic radiation.

1897
J. J. Thompson discovered the electron, a sub-atomic particle that is orbiting arround the nucleus of atoms, and that it was carried a negative electrical charge

1900
Max Planck proposed that “matter absorbed heat energy and emitted light energy discontinuously, in ‘lumps’.” Lumps became to be known as “quanta”, and with this discovery the foundation was laid for quantum mechanics.

1905
Albert Einstein published four papers:
1) A dissertation on the photo-electric effect – the phenomenon by which certain metals will emit electrons when their surface is struck by light.
2) A discussion of “Brownian movements”, about the behavior of atoms in certain specialized circumstances, and actually offered a measure of proof of the existence of atoms.
3) A paper entitled "On the Electrodynamics of Moving Bodies", Today know as “Einstein's Special Theory of Relativity”.
It blended Maxwell’s equations for electromagnetism with the Newtonian equations for mechanics, but it also took both into an entirely new realm, by contemplating the kinds of things that would happen at velocities approaching the speed of light.
4) A paper entitled "Does the Inertia of a Body Depend Upon Its Energy Content?", introduced the famous equation; E=mc2
Einstein's four papers introduced new theories of time and space, defined the relationship between mass and energy and reconciled it all with the commonly accepted theories of electromagnetism. But there was no discussion of gravity.

1910
Robert Andrews Millikan published the results of his "oil-drop experiments" with which he calculating the charge of a single electron down to a constant value of about 1.602x10-19 coulomb.

1916
Albert Einstein published his theory of General Relativity "The Foundations of the General Theory of Relativity". He described gravity as a curvature in the space-time continuum, a distortion of the fabric of space caused by the presence of a massive object like a planet or a star. A universe where space could be curved and distorted, and time was elastic.

1919
Sir Arthur Eddington confirmed Albert Einstein's theory of General Relativity. On an island off the coast of Africa, He observed a solar eclipse and concluded that the Sun indeed caused the light of distant stars to bend as it approached the Earth.

1923
Albert Einstein published the first in a series of papers “Unified Field Theory.” Goal: to express both gravity and electromagnetism in one all-encompassing mathematical formula. This search would ultimately dominate the remainder of his life.