In http://arxiv.org/abs/gr-qc/0407052 Meissner gave two possible values for the Immirzi, a number important in QG. On page 3 one sees(adsbygoogle = window.adsbygoogle || []).push({});

0.23753295796592... and also 0.273985635...

AFAIK this paper is the first place the two numbers appeared. It was a correction of some earlier estimated bounds involving log 2 and log 3 and pi.

Meissner thought that the first (0.237...) was right, but he said with a different assumption you get the other (about 0.274)

Then, in a series of papers Ghosh and Mitra said that the second one, 0.274, was the right one. They were counting black hole states by brute force. Anyway that is how it looks to me---see for yourself:

http://arxiv.org/abs/gr-qc/0401070

http://arxiv.org/abs/gr-qc/0411035

http://arxiv.org/abs/gr-qc/0603029

You must judge for yourself. I am persuaded that the earlier researchers (Ashtekar, Baez, Krasnov...) were almost right with the log 2 etc. and that Meissner was closer still. But I think Ghosh and Mitra hit it. I think it is 0.274 and it will stay that way now.

At one time people were citing papers about Black Hole VIBRATIONS in connection with this but I dont see any references to this any more in the recent papers. the "quasi-normal mode" (QNM) calculations were classical and apparently are not now considered relevant.

Of particular interest in the new work is a LOG CORRECTION TERM. Ghosh and Mitra are concerned with determining the coefficient of that term.

At this point there comes a new paper by Corichi et al. They used numerical methods (computer) to count the states in small black holes and graph the results, and fit curves.

http://arxiv.org/abs/gr-qc/0605014

The entropy is NOT simply equal to 1/4 of the area. The ratio depends on the size of the hole and there are correction terms.

So Corichi et al explore the regime of small holes and get plots. they find the number that fits is 0.274.

So that is good news for Ghosh and Mitra.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Immirzi 0.274 (Meissner+Ghosh+Mitra+Corichi et al)

**Physics Forums | Science Articles, Homework Help, Discussion**