Tuesday, January 27, 2015

Kerr Black Hole

Kerr Black Hole – An Uncharged Black Hole

A Kerr black hole is an uncharged black hole, a kind of a black hole which possesses only mass and angular momentum,that tends to rotate around a central axis and is named after Roy Kerr, a New Zealand mathematician who became the first person to solve the field equations. In 1963, Kerr had achieved something which eluded other scientist for around 47 years and he found the solution of Einstein’s general theory of relativity for a situation of this type.

He describes the space outside a rotating star or black hole and his solution has been described as `the most important exact solution to any equation in physics. Kerr black holes could be the most common in nature as the massive stars from which they form, possess rotation though no overall charge, before they collapse at the end of the life. With the principle of conservation of angular momentum, most of the spin is retained by the black hole after the star’s terminal collapse. A Kerr black hole comprises of the distinct regions namely ring singularity, ergosphere, inner and outer event horizons and static limits – the boundary between the ergosphere and the normal space.

Kerr Black Hole - Theoretical

At every event horizon, the roles of space and time tend to change and in the case of a Kerr black hole, space and time swap places twice which are the result of the metrical geometry equations of Kerr. While the singularity is also a temporary one, it can be avoided.

The concept focuses on neutron stars which are massive collapsed stars, the size of Manhattan though with a mass of Earth’s sun and if the dying stars collapse into a rotating ring of neutron stars, the Kerr postulates and their centrifugal force would prevent them from turning into a singularity. Kerr is of the belief that since the black hole does not have singularity; it would be quite safe to enter without any fear of the infinite gravitational force at the centre.

There is a possibility of escaping a black hole though not through the same way one went in. By leaving the black hole one will find either a region of negative space, - the physical explanation of which is unknown or in a different universe. Kerr black holes are purely theoretical and if they tend to exist, they offer adventurous time traveller, a one way trip in the past of the future.

Deepened Understanding of Astrophysics & Gravitational Theory

Though a tremendously advanced civilization could develop a means of calibrating a method of time travel, it is not possible to tell where or when a wild Kerr black hole could leave you.His achievement of identifying an exact solution for the rotating case, was something several people were speculating about and was a revolution in astrophysics and brought in a decade which could be known as `the Golden Age of Black Hole Physics’ when General Relativity saw Renaissance. The Kerr solution has pivoted in deepening our understanding of astrophysics as well as gravitational theory and over the years since its discovery, several new effects emerged in the Kerr solution - a rotating objects drags space with it which would be impossible in Newton’s theory.