When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Event horizon - Wikipedia

    en.wikipedia.org/wiki/Event_horizon

    In astrophysics, an event horizon is a boundary beyond which events cannot affect an outside observer. Wolfgang Rindler coined the term in the 1950s. [1]In 1784, John Michell proposed that gravity can be strong enough in the vicinity of massive compact objects that even light cannot escape. [2]

  3. Schwarzschild radius - Wikipedia

    en.wikipedia.org/wiki/Schwarzschild_radius

    The Schwarzschild radius or the gravitational radius is a physical parameter in the Schwarzschild solution to Einstein's field equations that corresponds to the radius defining the event horizon of a Schwarzschild black hole. It is a characteristic radius associated with any quantity of mass.

  4. Kerr metric - Wikipedia

    en.wikipedia.org/wiki/Kerr_metric

    The Kerr metric or Kerr geometry describes the geometry of empty spacetime around a rotating uncharged axially symmetric black hole with a quasispherical event horizon.The Kerr metric is an exact solution of the Einstein field equations of general relativity; these equations are highly non-linear, which makes exact solutions very difficult to find.

  5. Kruskal–Szekeres coordinates - Wikipedia

    en.wikipedia.org/wiki/Kruskal–Szekeres_coordinates

    The black hole event horizon bordering exterior region I would coincide with a Schwarzschild t-coordinate of + while the white hole event horizon bordering this region would coincide with a Schwarzschild t-coordinate of , reflecting the fact that in Schwarzschild coordinates an infalling particle takes an infinite coordinate time to reach the ...

  6. Hawking radiation - Wikipedia

    en.wikipedia.org/wiki/Hawking_radiation

    The region beyond which not even light can escape is the event horizon: an observer outside it cannot observe, become aware of, or be affected by events within the event horizon. [ 5 ] : 25–36 Picture of space falling into a Schwarzschild black hole at the Newtonian escape speed .

  7. Kerr–Newman metric - Wikipedia

    en.wikipedia.org/wiki/Kerr–Newman_metric

    The Kerr–Newman metric describes the spacetime geometry around a mass which is electrically charged and rotating. It is a vacuum solution which generalizes the Kerr metric (which describes an uncharged, rotating mass) by additionally taking into account the energy of an electromagnetic field, making it the most general asymptotically flat and stationary solution of the Einstein–Maxwell ...

  8. Gibbons–Hawking effect - Wikipedia

    en.wikipedia.org/wiki/Gibbons–Hawking_effect

    For example, Schwarzschild spacetime contains an event horizon and so can be associated a temperature. In the case of Schwarzschild spacetime this is the temperature T {\displaystyle T} of a black hole of mass M {\displaystyle M} , satisfying T ∝ M − 1 {\displaystyle T\propto M^{-1}} (see also Hawking radiation ).

  9. Horizon (general relativity) - Wikipedia

    en.wikipedia.org/wiki/Horizon_(general_relativity)

    A horizon is a boundary in spacetime satisfying prescribed conditions. There are several types of horizons that play a role in Albert Einstein 's theory of general relativity : Absolute horizon , a boundary in spacetime in general relativity inside of which events cannot affect an external observer