My understanding is that a Kerr black hole is a theoretical type of black hole formed out of a dying, rotating star. The resulting rotation of the black hole causes a distortion of spacetime in the form of an elliptical region surrounding the event horizon in which particles MUST move and must move at the speed of light (C), due to frame-dragging. This spacetime region is called the ergosphere and is travelling faster than the rest of spacetime around it, at speed C.
Firstly, is this understanding correct?
Secondly, it is hypothesised that a Kerr black hole allows for closed time-like curves in spacetime (CTCs), but I fail to understand how and why.
Finally, how might one use this phenomena to travel in time and in what direction (past/future/both)? Additionally, would it be plausible to travel throughout all of history, or are there limits?
A Kerr Black Hole is a type of black hole that possesses only mass and angular momentum (but not electrical charge – the third possible property of a black hole). In other words, a Kerr black hole is an uncharged black hole that rotates about a central axis. It is named after the New Zealand mathematician Roy Kerr who, in 1963, became the first person to solve the field equations of Einstein’s general theory of relativity for a situation of this kind.
Kerr black holes are probably the commonest in nature, since the massive stars from which they typically form possess rotation (but no overall charge) before they collapse at the end of their lives. By the principle of conservation of angular momentum, much of this spin is then retained by the black hole following the star’s terminal collpase.
A Kerr black hole has the following distinct regions:
1. Ring singularity
2. Inner and outer event horizons
3. Ergosphere – The Kerr black hole consists of a rotating mass at the center, surrounded by two event horizons. The outer event horizon marks the boundary within which an observer cannot resist being dragged around the black hole with space-time. The inner event horizon marks the boundary from within which an observer cannot escape. The volume between the event horizons is known as the ergosphere.
4. Static limit (the boundary between the ergosphere and normal space)
At each event horizon the roles of space and time are reversed; so, in the case of a Kerr black hole space and time swap places twice. The singularity is ring-shaped and, except if approached on its equatorial plane, is repulsive. This fact is simply the result of the equations of Kerr’s metrical geometry. The singularity is also a temporal one, so that it can be avoided. In theory, it is possible to escape from a black hole, although not by the same way you went in. On leaving the black hole you would find yourself either in a region of "negative space," the physical meaning of which is unclear, or in an entirely different universe.
February 14th, 2010 at 12:50 am
A Kerr Black Hole is a type of black hole that possesses only mass and angular momentum (but not electrical charge – the third possible property of a black hole). In other words, a Kerr black hole is an uncharged black hole that rotates about a central axis. It is named after the New Zealand mathematician Roy Kerr who, in 1963, became the first person to solve the field equations of Einstein’s general theory of relativity for a situation of this kind.
Kerr black holes are probably the commonest in nature, since the massive stars from which they typically form possess rotation (but no overall charge) before they collapse at the end of their lives. By the principle of conservation of angular momentum, much of this spin is then retained by the black hole following the star’s terminal collpase.
A Kerr black hole has the following distinct regions:
1. Ring singularity
2. Inner and outer event horizons
3. Ergosphere – The Kerr black hole consists of a rotating mass at the center, surrounded by two event horizons. The outer event horizon marks the boundary within which an observer cannot resist being dragged around the black hole with space-time. The inner event horizon marks the boundary from within which an observer cannot escape. The volume between the event horizons is known as the ergosphere.
4. Static limit (the boundary between the ergosphere and normal space)
At each event horizon the roles of space and time are reversed; so, in the case of a Kerr black hole space and time swap places twice. The singularity is ring-shaped and, except if approached on its equatorial plane, is repulsive. This fact is simply the result of the equations of Kerr’s metrical geometry. The singularity is also a temporal one, so that it can be avoided. In theory, it is possible to escape from a black hole, although not by the same way you went in. On leaving the black hole you would find yourself either in a region of "negative space," the physical meaning of which is unclear, or in an entirely different universe.
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February 14th, 2010 at 1:18 am
Black holes and planets both distort space-time fabric but black holes also rupture them literally creating holes in the fabric.Through the holes,not even light escapes and through could be a distance of million miles and then link the space-time fabric back again.This means the distance could be covered at speeds faster than light,who knows if light cannot escape it should be faster than light!Einstein predicts that at relativistic speeds,time could be delayed for an observer in an inertial frame of reference,could be because of length contraction in the fabric.
That’s how i have understood things about such.
I seek more specific and logical theories on space and universe like einstein’s because they are bound to make a pattern. I think the universe is a puzzle game in infinite pieces! I can’t judge on your understanding but i find the details above!
And i can’t judge on your understanding,increasing knowledge and imagining is more important for me and everyone!
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