A new type of black hole to ask CERN about, as well as "bubbles of nothing"

New Scientist notes that a new type of black hole appears theoretically possible - a "black saturn":

Just like the central black hole, the ring would be defined by its event horizon, a boundary beyond which nothing can escape the object's gravity. The ring could be thin like a rubber band or fat like a doughnut, and the rotation would flatten it – "like a doughnut that you have squashed," says Elvang. The spinning ring would also drag space-time around with it, making the central black hole spin as well.

The black Saturn can only exist in a space with four dimensions, rather than the three we inhabit. In 3D, a black ring is impossible, so there are no big black Saturns out there for astronomers to spot – but at a microscopic level, they might really exist....

If extra dimensions exist, black Saturns might be produced in the Large Hadron Collider (LHC) particle accelerator in Geneva, due to open at the end of 2007. Because there are so many ways to make a black Saturn, with different sizes of ring and different spins, they might even be produced in greater numbers than 'ordinary' black holes.

Actually, I had noticed the arxiv paper on this recently, but as it was not clear whether the authors thought they may be made by a particle accelerator, I did not post about it.

New Scientist notes that, as with any micro black hole, the physicists expect it will evaporate instantaneously into Hawking Radiation, but as long time readers are aware, a few credible scientists wonder whether HR really exists.

So, if a stable (non evaporating) "black saturn" is created, would its ability to absorb particles be greater that your "normal" micro black hole? How would a string of them created close together interact? Let a bunch of slow moving ones sink into the centre of the earth and what happens?

Of course, CERN's other big argument against there being any danger from micro black holes is that the moon and earth have been bombarded by cosmic rays with much higher energies for billions of years, so if they are still here any micro black holes that can be created are not planet eaters. However, as long time readers would know, there are arguments that question this analysis. (Basically, ones created at CERN may be slow moving and readily fall into the earth. Ones made by cosmic rays move fast and may zip right through most astronomical bodies)

(One day I will get around to tagging my old posts on micro black holes, but my first long article is here. For the others, a use the blog search on this page and they will all appear.)

My argument remains that CERN appears to have done a poor job at taking risk analysis seriously. They have very high expectation that HR is really the answer, even though this radiation has not been observed anywhere. (Yet it is possible that the decay debris could be observed in the Earth's atmosphere if evaporating micro black holes are being created there by cosmic ray collisions. It is just, I think, that not enough experimental work has been done yet to clearly answer the question of whether it is there.)

There is plenty of theoretical work coming out all the time that raises questions about the very nature of black holes and their decay process that should be taken into account in proper risk assessment. If CERN is actually looking at each case and coming up with good reasons why they are not a risk, even if HR does not exist, it would nice of them to tell us. Instead, it seems to just all be on a "trust us we know what we are doing" basis.

Here's one other thing I have been reading about lately: the idea of "bubbles of nothing" being created as part of black hole decay. Some of these, if I understand it correctly, could expand and be a danger. As noted in a recent arxiv paper:

Horowitz [20] has recently argued that a class of charged bubbles of nothing are a possible
decay product of black holes/strings/branes in quantum gravity. If true this would be a new,
unsuspected and disastrous endpoint of quantum black hole dynamics.

They don't explain exactly what they mean by "disastrous endpoint", but I would like to know more. (It may be that the authors of the paper think there is no danger anyway, but they do not write in anything resembling plain enough English for the layperson to understand their points.)

Has CERN looked at this work? Are there reasons to also question the "cosmic ray" analogy that I expect may also be used to argue against danger?

All question worth asking, I think, but getting answers is not easy.