What is a Black Hole?

* It is a region where matter collapses to infinite density and where the resulting curvature of space-time is extreme. It is a region in space from which nothing can escape, except for the radiation that leaks out.

* There are two basic kinds of black holes: Stellar and Supermassive

What is a White Hole?

*A white hole is the reverse version of a black hole. In fact, if a black hole can only suck things in, a white hole can only spit things out.

* Einstein's equations for black holes still function in reverse. But, white holes likely do not exist, because producing a white hole is just as difficult as destroying a black hole.

What is a Wormhole?

* Wormholes have not been proven to exist. But, the possible combination of a black hole linked to a white hole is called a wormhole.

* In effect, if the interior of an electrically charged or rotating black hole could join up with a white hole, then you would fall into the black hole and pop out of the white hole.

* The white hole may be very far from the black hole; it may even be in another universe!

* They sound pretty cool, but even if a wormhole formed, it would not be stable. Even the slightest disturbance would cause it to collapse.

* If wormholes exist and are stable, they would be quite unpleasant to travel through. The X-ray and gamma radiation that pours into the wormhole would cause you to get fried. Toast. Crispy. Ouch!

What is a Tachyon?

* The Latin word "tachys" means fast. A tachyon is a particle that travels faster than the speed of light. Tachyons have never been found to exist, although scientists are searching for them.

* Albert Einstein's theory of relativity says that nothing traveling slower than the speed of light can ever travel faster than 186,000 miles per second (the speed of light). But FTL's (faster than light) could potentially exist IF they never traveled slower than the speed of light.

* Luxons travel at the speed of light. The name given for the massless particle that travels at the speed of light is the "photon." Gravitons and possible neutrinos are other kinds of luxons.

* The Latin word "tardys" means slow. Tardyons are things that travel slower than the speed of light. They include things like protons, electrons, neutrons and other subatomic particles of matter.

* If an alien, made entirely of tachyons, came toward you from his spaceship, you would see him arrive before you saw him leave his ship. The image of him leaving his ship would take longer to reach you than his actual FTL body. The creature would also visually appear to be traveling away from you. This means you would see a tachyonic alien as receding backward in time!