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marcus

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## Main Question or Discussion Point

this seems to be an interesting paper,

though I can't tell for sure (don't understand the idea of naked singularity well enough, how you can have one)

http://arxiv.org/abs/gr-qc/0506129

Rituparno Goswami, Pankaj S. Joshi, Parampreet Singh

4 pages, 2 figures

"We investigate here gravitational collapse of a scalar field model which classically leads to a naked singularity. We show that non-perturbative semi-classical modifications near the singularity,

I've been looking up earlier Pankaj Joshi papers. I believe he is considered expert on the end states of gravitational collapse and on naked singularities. I don't understand about naked singularities. Apparently if the collapsing matter starts out distributed right you can have collapse without an event horizon forming.

If anyone has some intuition they want to share, please do.

In Loop Quantum Cosmology an inhomogeneous model (spherically symmetric) is being worked out. able to deal with this. an earlier LQC result was that inflation is generic in a BB. you dont have to explain it by postulating something extra, you get it out of the basic LQC model.

something like that seems to be happening here.

Goswami, Joshi, Singh talk about a "negative pressure" quantum effect which blows apart the singularity that is trying to form

so there is a burst of energy and you NEVER GET a naked singularity.

it sounds to me like they are talking about something like a GRB gammaray burst mechanism

Of course LQG and the applied version symmetry-reduced LQC could both be wrong---but we dont know that they are wrong and they keep going ahead and getting interesting results. Assuming it is not wrong, this result is very curious.

Maybe we should give these three authors a handle like GJS or G-J-S and keep tabs on this paper. and earlier papers by Joshi about naked sings and collapse endstates and stuff.

though I can't tell for sure (don't understand the idea of naked singularity well enough, how you can have one)

http://arxiv.org/abs/gr-qc/0506129

**Quantum evaporation of a naked singularity**Rituparno Goswami, Pankaj S. Joshi, Parampreet Singh

4 pages, 2 figures

"We investigate here gravitational collapse of a scalar field model which classically leads to a naked singularity. We show that non-perturbative semi-classical modifications near the singularity,

**based on loop quantum gravity, give rise to a strong outward flux of energy. This leads to the dissolution of the collapsing cloud before a naked singularity can form.**Quantum gravitational effects can thus censor naked singularities by avoiding their formation. Further, quantum gravity induced mass flux has a distinct feature which can lead to a novel observable signature in astrophysical bursts."I've been looking up earlier Pankaj Joshi papers. I believe he is considered expert on the end states of gravitational collapse and on naked singularities. I don't understand about naked singularities. Apparently if the collapsing matter starts out distributed right you can have collapse without an event horizon forming.

If anyone has some intuition they want to share, please do.

In Loop Quantum Cosmology an inhomogeneous model (spherically symmetric) is being worked out. able to deal with this. an earlier LQC result was that inflation is generic in a BB. you dont have to explain it by postulating something extra, you get it out of the basic LQC model.

something like that seems to be happening here.

Goswami, Joshi, Singh talk about a "negative pressure" quantum effect which blows apart the singularity that is trying to form

so there is a burst of energy and you NEVER GET a naked singularity.

it sounds to me like they are talking about something like a GRB gammaray burst mechanism

Of course LQG and the applied version symmetry-reduced LQC could both be wrong---but we dont know that they are wrong and they keep going ahead and getting interesting results. Assuming it is not wrong, this result is very curious.

Maybe we should give these three authors a handle like GJS or G-J-S and keep tabs on this paper. and earlier papers by Joshi about naked sings and collapse endstates and stuff.

**the earlier papers might actually explain more**because they are earlier and you can easily get them listed by the arxiv search engine.