White Holes

White Holes are time-inverted black holes. A black hole is the ultimate state of a process in which matter collapses under gravity in all the denser and denser state, until the surface gravity becomes so strong that even light can escape. Shortly after this ("soon" for an observer standing on the surface of stars, the distant observer this process takes infinitely long) matter is completely collapsed into a state of infinite density, which we call a singularity.
At the white hole everything is going the other way around: from the singularity "raise " the matter and spreads around. For outside observers of both holes, black hole is an object that just swallows matter and becomes larger and can not be destroyed (if we ignore Hawking radiation), while white hole emits only matter, and becoming smaller and can not be created. She was there at the time of the Big Bang, and a "cause" of its existence is in its future.
From this can be seen that the white holes are paradoxical objects (do not respect the second law of thermodynamics) and hence many believe that they can not exist in nature. Some of the reasons why they still appear in the scientific literature are as follows: Einstein's theory is symmetric to time inversion, so if black holes appears in it (and they occur) then the white holes have to occur. It does not mean that they occur in nature that except with Einstein's theory must be consistent with other laws of nature (thermodynamics). Inside Einstein's theory, however, they may be interesting to observe from a purely academic-theoretical reasons.
"Black holes in our universe may connect to white holes elsewhere in the Universe , and White holes perform exactly opposite of black holes", which means that the black and white hole are in such a way linked to the Earth. If white holes really exist, they are in another universe with separate space - time to ours. White holes are the output of black holes. Where the white holes eject matter is not known.