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General Relativity Explained

Have you ever heard about General relativity? 

General relativity is a remarkable theory published by the well known physicist Albert Einstein.

Let us know more about general relativity.

General relativity is the geometric theory of gravitation published by Albert Einstein.

Albert Einstein published this theory in 1915.

It is the current description of gravitation in modern physics.


General relativity generalizes special relativity and Newton's law of universal gravitation, and gives a unified description of gravity as a geometric property of space and time, or space-time.


THE CURVATURE OF SPACE-TIME AND THE EINSTEIN FIELD EQUATIONS

The curvature of space-time is directly related to the energy and momentum of whatever matter and radiation are present.

The relation is specified by the Einstein field equations. That is a system of partial differential equations.

The Einstein field equations comprise a set of 10 equations in Albert Einstein's general theory of relativity

These equations describe the fundamental interaction of gravitation as a result of space-time being curved by mass and energy.



BUT WHAT ARE PARTIAL DIFFERENTIAL EQUATIONS?

A partial differential equation or a P.D.E is a differential equation containing unknown multi-variable functions and their partial derivatives.


P.D.Es are used to formulate problems involving functions of several variables, and are either solved by hand, or used to create a computer model.


Ordinary differential equations or O.D.Es deal with functions of a single variable and their derivatives.


Some predictions of general relativity differ significantly from those of classical physics, especially concerning the passage of time like:

• The geometry of space,

• The motion of bodies in free fall.

• The propagation of light.

Examples of such differences include gravitational time dilation, gravitational lensing, the gravitational red-shift of light, and the gravitational time delay.


The predictions of general relativity in relation to classical physics have been confirmed in all observations and experiments to date.


General relativity is not the only relativistic theory of gravity but it is the simplest theory that is consistent with experimental data.

Widely acknowledged as a theory of extraordinary beauty, general relativity has often been described as the most beautiful existing physical theories.

Albert Einstein had spent 10 years trying to include acceleration in his theory.

He published his theory of general relativity in 1915. In it, he determined that really massive objects cause a distortion in space-time. This distortion is felt as gravity.


The force between any two bodies depends on how massive each one is and how far apart the two lie. 

Sir Isaac Newton quantified the gravity between two objects when he formulated his three laws of motion. 

Even as the center of the Earth is pulling you toward it, keeping you on the ground firmly, your center of mass is pulling back at the Earth. 


But the more massive body barely feels the pull from you, while with your much smaller mass you find yourself firmly rooted because of that same force.  




The general theory of relativity was published by Albert Einstein:

                                                                  Source of the image

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