A heck of a lot. E=mc^2 is the best known but the least of his many discoveries.
In 1905, the "annus mirabilis" (miraculous year), he published three important papers, on Brownian motion, the photoelectric effect, and special relativity. In fact, his Nobel prize was for the photoelectric effect (NOT relativity, which includes E=mc^2).
Brownian motion was first noticed by a botanist who saw pollen in water randomly moving around. Einstein demonstrated a mathematical basis for this "random" motion that depended on water being composed of atoms. This was the final proof of the atomic theory - until then, although convenient and pretty well accepted, there was no definite proof of atoms. Newton's papers showed that atoms had to exist or Brownian motion wouldn't happen.
The photoelectric effect is shown by solar cells (like on a solar-powered calculator). Certain parts of the effect - like how the amount of electricity produced depends on the wavelength (color) of the light but not on how bright it is - puzzled scientists who had thought that light behaved as waves. Einstein had recently heard of Max Planck's theory that mathematically pretended light was made of packets of energy, and he assumed that light actually WAS these packets (which are now called photons or quanta). This explained the photoelectric theory much better, and although nobody liked thinking of light as particles, not waves, it led to today's well accepted theory of wave-particle duality.
Then Einstein developed special relativity, which said that the laws of physics are the same everywhere, and are *relative* to the observer's viewpoint. One of these laws is the speed of light, the universe's "speed limit". So even if you're traveling at a certain speed, the speed of light is still the same. In fact there is nobody to say that you're traveling or not, because of relativity: imagine an empty universe. Suppose you're in a rocketship and you accelerate for 10 seconds and then cut off the engines. How can you tell how fast you're going? There's nothing else, so you might as well say you're still at rest. If you were in an empty universe in a spacesuit and another person floated by, how can you tell who's moving - you, them, or both?
So because the speed of light is the same, there are certain changes as something approaches the speed of light FROM AN OBSERVER'S REFERENCE FRAME - to the object itself, it's still working as normal. For example, it becomes increasingly harder for the observer to accelerate this object any more, in that the same force won't accelerate it quite as much. (Because of F=ma this means that the effective mass of the object actually increases.) To the object itself, the observer has a harder time pushing itself away. This ultimately reaches the point where it becomes infinitely hard to accelerate the object to the speed of light. Similarly, lengths get shorter and time expands for related reasons - the exact mathematical proof is involved, but the general idea is that the speed of light must remain the same. If the observer shines a flashlight, the observer AND the object must measure the light from it at the speed of light, which means that somewhere along the way speed gets distorted. It sounds confusing but it yields a consistent mathematical system.
One of the side results of this equivalence is the formula E=mc^2. Energy = mass * speed of light squared (not acceleration, not circumference, honestly what are you people smoking!?). The usefulness of this equation is that a small amount of mass, times the speed of light squared (since the speed of light is so large), yields an incredible amount of energy. This is the principle behind atomic bombs and nuclear submarines. A few POUNDS of uranium, if some amount of its mass is converted directly to energy (and the rest to a lighter object like lead), yields a large explosion equivalent to many MEGATONS of TNT or other conventional explosive.
The next concept he developed, some years later, was general relativity. This is the concept of the curvature of space-time. General relativity is like special relativity, but it accounts for gravity. Basically, heavy objects distort the fabric of space (and time, the 4th dimension), by making a "dent" in it, so other objects "fall into the dent" or orbit around it like the coin in that spinning vortex thing you see in malls. This explains gravity as a function of the universe, not as an external force.
He discovered that the only thing that is constant is the speed of light.
Also he discovered that if you move very fast then time slows down and if you travel at the speed of light time stops (for you not for everyone else). If you were to travel faster than the speed of light you would move back in time (this is probably impossible to do though). Also if you move very fast you become bigger and heavier
A lot of other things but they would be too hard to explain without using formulas.
E = mc squared is energy = mass x speed of light squared.
he didn't physically "discover" anything. He was a scientist not an explorer or an inventor. He came up with the theory of relativity. You know E=mc^2.
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A heck of a lot. E=mc^2 is the best known but the least of his many discoveries.
In 1905, the "annus mirabilis" (miraculous year), he published three important papers, on Brownian motion, the photoelectric effect, and special relativity. In fact, his Nobel prize was for the photoelectric effect (NOT relativity, which includes E=mc^2).
Brownian motion was first noticed by a botanist who saw pollen in water randomly moving around. Einstein demonstrated a mathematical basis for this "random" motion that depended on water being composed of atoms. This was the final proof of the atomic theory - until then, although convenient and pretty well accepted, there was no definite proof of atoms. Newton's papers showed that atoms had to exist or Brownian motion wouldn't happen.
The photoelectric effect is shown by solar cells (like on a solar-powered calculator). Certain parts of the effect - like how the amount of electricity produced depends on the wavelength (color) of the light but not on how bright it is - puzzled scientists who had thought that light behaved as waves. Einstein had recently heard of Max Planck's theory that mathematically pretended light was made of packets of energy, and he assumed that light actually WAS these packets (which are now called photons or quanta). This explained the photoelectric theory much better, and although nobody liked thinking of light as particles, not waves, it led to today's well accepted theory of wave-particle duality.
Then Einstein developed special relativity, which said that the laws of physics are the same everywhere, and are *relative* to the observer's viewpoint. One of these laws is the speed of light, the universe's "speed limit". So even if you're traveling at a certain speed, the speed of light is still the same. In fact there is nobody to say that you're traveling or not, because of relativity: imagine an empty universe. Suppose you're in a rocketship and you accelerate for 10 seconds and then cut off the engines. How can you tell how fast you're going? There's nothing else, so you might as well say you're still at rest. If you were in an empty universe in a spacesuit and another person floated by, how can you tell who's moving - you, them, or both?
So because the speed of light is the same, there are certain changes as something approaches the speed of light FROM AN OBSERVER'S REFERENCE FRAME - to the object itself, it's still working as normal. For example, it becomes increasingly harder for the observer to accelerate this object any more, in that the same force won't accelerate it quite as much. (Because of F=ma this means that the effective mass of the object actually increases.) To the object itself, the observer has a harder time pushing itself away. This ultimately reaches the point where it becomes infinitely hard to accelerate the object to the speed of light. Similarly, lengths get shorter and time expands for related reasons - the exact mathematical proof is involved, but the general idea is that the speed of light must remain the same. If the observer shines a flashlight, the observer AND the object must measure the light from it at the speed of light, which means that somewhere along the way speed gets distorted. It sounds confusing but it yields a consistent mathematical system.
One of the side results of this equivalence is the formula E=mc^2. Energy = mass * speed of light squared (not acceleration, not circumference, honestly what are you people smoking!?). The usefulness of this equation is that a small amount of mass, times the speed of light squared (since the speed of light is so large), yields an incredible amount of energy. This is the principle behind atomic bombs and nuclear submarines. A few POUNDS of uranium, if some amount of its mass is converted directly to energy (and the rest to a lighter object like lead), yields a large explosion equivalent to many MEGATONS of TNT or other conventional explosive.
The next concept he developed, some years later, was general relativity. This is the concept of the curvature of space-time. General relativity is like special relativity, but it accounts for gravity. Basically, heavy objects distort the fabric of space (and time, the 4th dimension), by making a "dent" in it, so other objects "fall into the dent" or orbit around it like the coin in that spinning vortex thing you see in malls. This explains gravity as a function of the universe, not as an external force.
He discovered that the only thing that is constant is the speed of light.
Also he discovered that if you move very fast then time slows down and if you travel at the speed of light time stops (for you not for everyone else). If you were to travel faster than the speed of light you would move back in time (this is probably impossible to do though). Also if you move very fast you become bigger and heavier
A lot of other things but they would be too hard to explain without using formulas.
E = mc squared is energy = mass x speed of light squared.
c is speed of light in this formula.
he didn't physically "discover" anything. He was a scientist not an explorer or an inventor. He came up with the theory of relativity. You know E=mc^2.
Theory of relativity. He also wrote a lullabye for his baby.
the energy formula
E=M(C)squared
energy = mass times acceleration squared
hey starrchick thats energy = mass * circumference squared
When humans use 100% of their brains they won't need bodies, one of his theories.
Definitely not a scissors.
theory of relativity
E=mc2
E=MC2