Special Relativity postulates that space and time are not absolute but are relative to the observer. This means that the measurements of space and time intervals depend on the motion of the observer.

Lorentz Transformations are a set of equations that allow us to transform the coordinates of an event from one inertial frame of reference to another. These transformations are essential for understanding the effects of relative motion on space and time.

Time Dilation is the phenomenon where time appears to slow down for objects moving at high speeds relative to an observer. This effect is predicted by Special Relativity and has been experimentally verified.

Length Contraction is the phenomenon where objects appear to shorten in the direction of motion when observed from a frame of reference moving relative to the object. This effect is also predicted by Special Relativity and has been experimentally verified.

Mass-Energy Equivalence is the principle that mass and energy are equivalent and can be converted into each other. This principle is expressed by the famous equation E=mc^2, where E is energy, m is mass, and c is the speed of light.

The speed of light in a vacuum is a fundamental constant in physics and is denoted by the letter c. It is equal to 299,792,458 meters per second.

The principle of relativity states that the laws of physics are the same for all observers in uniform motion. This means that there is no absolute frame of reference and that all motion is relative.

An inertial frame of reference is a frame of reference in which Newton's laws of motion hold true. This means that an object at rest will remain at rest and an object in motion will continue moving at a constant velocity unless acted upon by an external force.

The twin paradox is a thought experiment that illustrates the effects of time dilation. In the experiment, one twin stays on Earth while the other twin travels through space at a high speed. When the traveling twin returns to Earth, they are younger than their stay-at-home twin.

The Michelson-Morley experiment was an experiment that attempted to measure the speed of the Earth through the aether, a hypothetical medium that was thought to permeate space. The experiment found that the speed of light was the same in all directions, regardless of the motion of the Earth, which contradicted the theory of aether.

The Hafele-Keating experiment was an experiment that confirmed the predictions of time dilation. In the experiment, four atomic clocks were flown around the world on commercial airliners. When the clocks were compared at the end of the experiment, the clocks that had traveled around the world had lost time compared to the clock that had remained stationary.

The Global Positioning System (GPS) is a system of satellites that provides location and time information to users on Earth. GPS receivers use the signals from the satellites to calculate their position and time.

The Large Hadron Collider (LHC) is a particle accelerator located at CERN in Switzerland. It is the world's largest and most powerful particle accelerator and is used to study the fundamental particles of matter.

The Higgs boson is an elementary particle that gives mass to other particles. It was discovered at the LHC in 2012.