Dark Matter and Dark Energy

Glossary

Big Bang                                 A theory of cosmology that the expansion of the Universe began with a gigantic explosion approximately 13.8 billion years ago.

Big Crunch                              A theory of cosmology that the expanding Universe will eventually stop, reverse and return to a cloud of subatomic particles.

Big Rip                                    A theory of cosmology that the expanding Universe will infinitely expand to the point when there are no visible stars in the night sky.

“Cosmic Jerk”                          A theory of cosmology when an expanding Universe ceased its rate of expansion due to the gravitational attraction of dark matter, and then continued its expansion due to the pressure of dark energy.

cosmic inflation                      Expansion of the Universe beginning with the Big Bang.

dark energy                            A type of undiscovered energy representing 68% of all of the mass-energy in the Universe.

dark matter                            A type of undiscovered matter, with a mass, representing 27% of all of the mass-energy in the Universe.

“Einstein Cross”                      The light from a supernova that is distorted by dark matter and appears as four, simultaneous supernova explosions.  A type of gravitational lensing.

gravitational lensing             The distortion or bending of light due to the optical effects of gravity on that light.

space-time                              Any mathematical model that fuses the three dimensions of space and the one of time into a single 4-dimensional continuum.  Also called spacetime.

zero point energy       A seething mass of energy fluctuations within a vacuum at a temperature of absolute zero (0° Kelvin). AKA: ZPE.

Background