Question

What are white holes and why they can't exist practically? Explain.

:)

Answer 1

Hey there!

□ White hole is a hypothetical region of spacetime which cannot be entered from the outside, it is the reverse of a black hole, which can only be invited from the outside and from which even light cannot escape.

□ You can say it works as the opposite of a black hole. Everything that comes inside the black hole is throw out at a white hole.

□ It cannot practically exist since it cannot be produced by a black hole because the gravitational sheer, that black hole produces would be too great for a formation of a wormhole, i.e. it would be impossible for it to form because of all gravity produced by the black hole. 

I hope this helps.

Answer 2

white holes are opposite to black holes.
black holes sucks in every thing whereas white hole ejects everything sucked in by black hole. it is hypothesized that black causes tear in space or hole in space which opens in another universe which is white hole so matter which enters through black hole and exits from white hole.
practically its never been observed and it can only exist if multiverse theory is true and also that black holes are capable of connecting two universes.