Falling into a black hole

Abstract

String theory tells us that quantum gravity has a dual description as a field theory (without gravity). We use the field theory dual to ask what happens to an object as it falls into the simplest black hole: the 2-charge extremal hole. In the field theory description the wavefunction of a particle is spread over a large number of `loops', and the particle has a well-defined position in space only if it has the same `position' on each loop. For the infalling particle we find one definition of `same position' on each loop, but there is a different definition for outgoing particles and no canonical definition in general in the horizon region. Thus the meaning of `position' becomes ill-defined inside the horizon.

Figures (5)

• Figure 1: Field theory states
• Figure 2: Gravity solutions for different microstates
• Figure 3: Evolution in the classical state 1(a), 2(a).
• Figure 4: The state $\Psi_{in}$; the excitations have moved the same distance on each loop
• Figure 5: The state $\Psi_{out}$