## What is Relativity:

Relativity comes from ‘relative to’ indicating that there is no absolute reference point, that is, everything is explained taking into account the relationship it has with another reference. For example the relativity of values, cultural relativity or the relativity of sentences.

The most famous relativity is Albert Einstein's Theory of Relativity published in 1915 which includes both:

• the theory of Special Relativity: which defined the behavior of bodies of constant velocity,
• The theory of General Relativity: defines how the density of matter and / or energy determine the geometry of the space-time lines.

The theory of General Relativity takes as a principle that the laws of physics are the same anywhere in the Universe. Taking this into account, the theory formulates the behavior in space and in time of objects of variable speed in the Universe, taking into account the behavior of gravitational effects.

In this way, with the theory of General Relativity, the torsion of light due to gravity (gravitational waves) or the behavior of a planet with respect to its orbit can be predicted from the location and existence of black holes.

General Relativity defines the following constants:

• There is no absolute point of reference but points of reference in relation to another.
• The speed of light is constant. The speed of light is always the same no matter who measures it or how fast the person who is measuring it is going.
• Nothing can go faster than the speed of light. In fact it is the fastest speed detected in the Universe traveling at about 299,793 kilometers per second.