Black Holes and Wormholes
Black holes have been detected, studied and described. Wormholes are not there yet. For now they are only a hypothetical topological feature of spacetime - a postulated method within the general theory of gravity, of a "shortcut" for fast travel between two points in space and time.
Most of us have probably heard of black holes and wormholes. Black holes are real and science has been able to precisely describe their nature and the way light and matter behave once they get caught in a black hole’s deadly gravitational field. We know that black hole is a special area in space-time where gravity is so strong that it prevents anything, even light (technically – photons), from escaping. Existence of black holes has been predicted by the general theory of relativity which concludes that black holes are formed in certain spots in space where mass is heavily compacted. Black holes begin as giant stars (at least six times the mass of our Sun) and, after billions of years they collapse in on themselves into a point smaller than the full-stop at the end of this sentence. Nothing nearby can escape the pull of the resulting gravity.
Getting too close to a black hole would put you in a very grim position. Even at some distance outside the edge, it would take all the effort in the universe to resist getting pulled into orbit around the hole. Closer still, because of the sharp rate of increase of the forces, if your head was nearer the hole than your feet, the atoms in your hair would feel a stronger force than those in your toes. This difference would quickly tear you apart, turning you into a spaghetti-like line of atoms.
Wormholes, on the other hand, is a postulate within the same general theory of relativity. A wormhole is a theoretical passage through space-time that could create shortcuts for long journeys across the universe. Wormholes bring with them the dangers of sudden collapse, high radiation and dangerous contact with exotic matter. Einstein’s general theory of relativity mathematically predicts the existence of wormholes, but none have been discovered to date. A negative mass wormhole might be spotted by the way its gravity affects light that passes by.
Here is an interesting documentary explaining black holes and wormholes.
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