Proposed in 1905 in 'On the Electrodynamics of Moving Bodies'/assumes laws of physics are invariant in all inertial systems & c in a vaccuum is same for all observers

Geometric theory of gravitation/published 1915/curvature of spacetime is directly related to energy & momentum of matter & radiation present/represented by Einstein field equations

Theoretical framework in which the point-like particles of particle physics are replaced by one dimensional objects, first studied in late 1960s as a theory of strong nuclear force

First mentioned in 1924 by physicist Orest Chwolson, a distribution of matter that is capable of bending the light from the source as it travels to the observer

Actual difference of elapsed time between 2 events as measured by observers either moving relative to each other or differently situated from gravitational masses

Happens when light or other electromagnetic radiation from an object is increased in wavelength or shifted to the red end of the spectrum

A decrease in length measured by the observer of an object which is traveling at any non-zero velocity relative to the user, formally called Lorentz-FitzGerald contraction

The measure of mass is dependant on the velocity of the observer

Concept that the mass of an object or system is a measure of its energy content

The speed of light is the upper limit for the speeds of objects with positive rest mass

Concept that distant simultaneity – whether two spatially separated events occur at the same time – is not absolute, but depends on the observer's reference frame

Thought experiment in special relativity involving identical twins/one makes space journey at high-speed/returns home to find other twin aged more

Postulated by Oort in 1932/hypothetical matter that cannot be seen with telescopes but accounts for most of the matter in the Universe

Hypothetical, unknown form of energy which permeates all of space & tends causes universe to expand at accelerating rate

Object that absorbs all incident electromagnetic radiation, regardless of frequency or angle of incidence

Location where quantities used to measure the gravitational field become infinite in a way that does not depend on the coordinate system/universe at beginning of Big Bang

Boundary in spacetime beyond which events cannot affect an outside observer/point at which gravitational pull becomes so great as to make escape impossible/point of no return!

Mathematically defined region of spacetime exhibiting such a strong gravitational pull that no particle or electromagnetic radiation can escape from it

Problem in general relativity which determines the motion & gravitational field of 2 bodies as described by the field equations of general relativity/also known as Two-Body Problem

Set of results in general relativity which attempt to answer the question of when gravitation produces singularities

Unit of time created purely from dimensional analysis which gives the time required for light to travel in a vacuum 1 Planck length

Also called Noodle Effect/vertical stretching and horizontal compression of objects into long thin shapes in a very strong non-homogeneous gravitational field such as near black ho

Radius of sphere such that if all mass of object were compressed w/in it the escape velocity would be the speed of light/below this radius light can't escape & black hole is formed

The laws of physics are the same in all inertial reference frames

The speed of light in free space has the same value 'c' in all inertial frames of reference

Objects in deep space have a relative velocity away from Earth/this velocity is proportional to their distance from the Earth for galaxies up to a few hundred megaparsecs away

A hypothetical topological feature that would fundamentally be a shortcut linking two separate points in spacetime, also known as a wormhole

Test of general relativity that measures the precession of the perihelion of a orbiting body, first used on Mercury and successfully unified relativity and newton's laws

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