Can somebody please tell me in plain english what the theory of relativity is?

Answer 1

I'll try. Suppose that you want to measure the speed of something. There must be something used as a reference, such as the ground. The something is called a reference frame. Examples: a train may be moving at 60 mph with respect to the ground. The earth is orbiting the sun at 66,000 mph with respect to a frame stationary with respect to the average motion of nearby stars.

Newton's laws describe the sum of two velocities as simply their vector sum, in any reference frame. Example: if two trains are approaching each other, and one is moving at 40 mph and the other at 50 mph (as measured against a reference frame of the ground), the combined velocity will be 90 mph (with respect to a reference frame on either train).

This all seemed pretty obvious until two physicists named Michelson and Morley set out to find an absolute reference frame for measuring the velocity of light. The question: if light is traveling at 186,000 mph, what is the special reference frame that gives that speed? The surprising result of the experiment was that there exists no such special reference frame: every reference frame, no matter how it is moving, will see the speed of light as the same number.

It does not take much thought to see that the Newtonian addition of velocities rule cannot work for light. Using some mathematics developed by Lorentz, Einstein developed a new addition of velocities rule which worked both for slow motion (where Newton's laws give correct answers) as well as motion at or approaching the speed of light (where Newton's laws give disgustingly wrong answers). The famous equation e = m c squared was a consequence of this. So is the result that you cannot go faster than the speed of light.

So, now if someone asks you, What is the theory of relativity, you can say: "It means that there is no such thing as a preferred reference frame: all are equivalent," and have some understanding of what you are talking about.

Note that the above applies to the "special theory of relativity". Ten years after publishing it, Einstein came up with a "general theory of relativity", which applies to accelerated motion or motion in a gravitational field. I won't go into that here.

Einstein won a Nobel prize, but it was not for either of the theories mentioned here: it was for his description of photoelectricity.

Answer 2

It applies to motion .
the only movement possible must be measured against the postion of something else.
If you had a single object in space, you could not tell if it was moving or not because there is no other object to compare it to or "relate" the motion to.
your apparent motion is thus relative to those things about you, such as trees , buildings, etc.

Since time is a form of motion, it too is relative to other things that surround it and the relative speed of an object can affect the passing of time on that object.
so if you move away from earth at a fast speed and then return at a fast speed, you will find that the people on earth have aged faster than you and your clock is behind theirs.
thus time is relative to speed, that is the gist of the theory.

Answer 3

SRT are based on two laws.
1) The First law of SRT - the speed of a quantum of light in vacuum has
a maximal magnitude (constant, absolute) of c=1.
2) The second law - no other particle can travel with the speed c = 1.
Hence, a quantum of light is a privileged particle and SRT
examines the behaviour of a quantum of light in the Vacuum. SRT solve the problem:
that will take place, if quantum of light will change the rectilinear movement c=1.
He can change the rectilinear movement c=1 only on rotary movement.
And then these changes are described by the Lorentz transformations.
The circle turns to a sphere. And he works as electron .
And in this item electron is connected to electrodynamics of Maxwell.
In Maxwell's theory, the electron is considered local,
as though the particle is "at rest".
This means that it particle does not move rectilinearly,
but rotates around the diameter (has the form of a sphere).
The rotation of the electron creates electrical waves.
And then at the beginning of the last century many scientists
(Einstein, Lorents, Fitzgerald, Poincare, Abraham) were interested in the question:
What will take place, if the electron (Maxwell's) begins to move - rectilinearly?
All of them came to the conclusion that there would be radical changes with the electron.
These changes are described by the Lorentz transformations.
* * *
What borders of change the electron,s parameters ?
The Quantum theory approves, that at interaction electron with Vacuum
its parameters get infinite magnitudes.
It is possible only then the geometrical form of electron - sphere will be
transformed in flat phantom - circle.
Electron and quantum of light is one particle, which can be in different physical condition.
* * *
Such simple explanation seems surprising.
But business that the Quantum theory and SRT describe the beginning conditions
of Existence .
And beginning conditions can not be complex (difficult).
The development and evolution of Existence goes from simple to complex .

Answer 4

Unfortunately Rosh, that's incorrect. It has to do with the speed something travels. If one twin were to move at a speed near the speed of light, such a thing would happen, yes.

Difficult question. In short, the theory of special relativity has to do with frames of reference and the speed of light. It claims that the closer to the speed of light an object moves the slower time, relative to other frames of reference, moves, also, distances become shorter. Einstien also shows that no object with mass can move at the speed of light or faster.

The theory of general relativity deals with the accepted explanation of gravity. It claims that an object with mass will distort spacetime and cause every object that actually orbits another object to, in reality, be moving in a straight line.

This is as simple as I can make it, hope it helps.

Answer 5

It's the interpretation of space and time as first formulated by Albert Einstein. It is the intrerpretatiton limited to systems that do not move or that move in constant speed in the area outside of influence of gravity. There are two main principles: the laws of physics are the same in any system, regardless of its speed; speed of the light is constant, regardless of its source and system in which it's been measured. Defining those two systems (one moving, one standing still) by their space coordinates and time coordinate, Einstein showed how the usual physical values are relative to each other, that is, how does their moving influence the time and dimensions.
Hope this helps.

Answer 6

Grandpa, Grandma, Mom, Dad, Brother, Sister, Aunts, Uncles, Cousins are all relatives. Everyone else isn't.

Answer 7

Suppose you are having a meter scale and a clock showing seconds.

Take similar meter scale and a clock which are now set into motion with another observer along with them.

If they move with a speed of 0.5 times the speed of light, the length of the meter scale reduces to 0.87 m. The time slows to 0.87 s. But the observer cannot compare it with the one at rest. Therefore, for him that 0.87 m is the one meter scale. And the 0.87 second will be one second for him.

As both length and time has decreased, he will measure the speed of light as that measured by us who are at rest.

If they move with a speed of 0.9times the speed of light, the length of the meter scale reduces to 0.44 m. The time slows down to 0.0.44m. Again he will measure the speed as the same.

If they move with a speed of 0.999999 times the speed of light, the length of the meter scale reduces to 0.0.0014141 m The time slows down 0.0.0014141 m Again he will measure the speed as the same.

Thus whatever their speed, the speed of light will be measured as C only.

The fundamental quantities mass, length and time are different and are changing with one’s speed in such a way that he will measure the speed of light always as C.

Therefore these quantities are not absolute; they are relative to one’s speed, whereas the speed of light is a constant or absolute.

This is the theory of relativity.

Before the theory of relativity we were under the impression that the length, mass and time are absolute and the speed of light must vary with the speed of the observers. Or length, mass and time are absolute and speed of light is relative.

The general theory of relativity deals with accelerated reference frame. With incorporating a necessary field of acceleration, any accelerated frame can the thought of as inertial frame of reference.

Answer 8

the laws of newton is about a body that moves at the low speed but at time of professor Einistien , the speed of light had been discoved then the laws of Newton did not true at the speed of light. then Einistine improved the laws of Mewton.he proposed some formula about mass, time , length at the very high speed.

Answer 9

The (hopefully) simple answer: Any characterist of an object you see (including length, mass, color, time) depend on how fast you are moving compared to the object. The only exception to that rule is the speed of light.

That's about as uncomplicated as I can make it... hope that helps.

Answer 10

This gives the relation between time and space. it says that as you go further in space time goes on reducing .The best eg is = two twins. u send one of them to space and the other remains on earth. after say 60 years you call them back the one on the earth would have grown older by 60 years but the other one be older by say 25.So you see the secret to remain young