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I often read the definition of event horizon of a black hole as the region where the escape velocity is bigger than the speed of light. However this would imply that if you're inside the event horizon you can -in theory- escape from black hole with constant acceleration (non-ballistic trajectories), like you can escape from the Earth's gravity with constant thrust without reaching escape velocity. However I know that inside the event horizon, space-time is bended and distorted so every path only leads to singularity. So is the general definition of event horizon stating that it's the boundry where escape velocity is > speed of light wrong?

For example http://www.britannica.com/topic/event-horizon-black-hole Even in Encyclopeadia of Britannica defines event horizon as:

Event horizon, Boundary marking the limits of a black hole. At the event horizon, the escape velocity is equal to the speed of light. Since general relativity states that nothing can travel faster than the speed of light, nothing inside the event horizon can ever cross the boundary and escape beyond it, including light.

regulus
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    See the above link, your definition of an event horizon is wrong. It has nothing to do with escape velocity. In fact it's a surprisingly complicated property of the entire spacetime. That is, you have to know the complete future history of the spacetime to know where the event horizon is. – John Rennie Apr 10 '16 at 18:47
  • That's the thing I'm asking, in many places it is defined as a concept of escape velocity (which I'm aware it's wrong). I updated my question with an example. – regulus Apr 10 '16 at 19:18

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