An update on the LHC, mini black holes and strangelets

There are a few things of note that have happened over the last couple of weeks:

1. Physicist Bee at the Backreaction blog gets a little cranky at having to address the issue, but she sets out in detail in this post why she believes there is no danger at all from mini black holes at the LHC. More importantly, she then respectfully answers those who question or doubt her in the long string of comments that follow. She insists that any arguments against Hawking Radiation existing are not convincing, but she makes many good points. (Including the preliminary one that the extra dimensions that are required to even make mini black hole production at the LHC plausible may not exist.)

Of particular interest in the comments section is the involvement of Walter Wagner, one of the litigants who is trying to stop the start up of the LHC because of perceived dangers.

I have said before that I was not sure what to make of Walter. He has had a varied career, and asking for donations to run a legal case is usually a reason to be concerned about motive. But, his comments in this post impress me. He appears sincere and knowledgeable. It's well worth reading this post and the comments in detail.

2. There's a recent paper on arXiv which does some number crunching on cosmic rays hitting the sun and earth and how they compare to the LHC. Perhaps it's easiest if I just copy the summary here:

The high energy cosmic ray flux impinging on the sun and earth for 4 Gyr is compared to the operation of the CERN Large Hadron Collider (LHC) at design energy and luminosity. It is shown by two different calculations that both the integrated luminosity and the total hadronic interaction rate from the cosmic ray flux of comparable energy are many orders of magnitude larger than that of the LHC operated for 10 years. This study indicates that it is extremely unlikely that pernicious exotic particles, such as mini-black holes, would be produced by the LHC that would destroy the earth.

Sounds good, except that it is still based on the assumption that Hawking Radiation exists, and therefore doesn't take into account the more complicated arguments as to why slow speed mini black holes created at the LHC might be more of a problem than high speed ones.

However, the section on strangelets (which are another potential worry, even though I haven't spent much time discussing them here) sounds more definitive. Taylor calculates that a negatively charged strangelet would be stopped by the sun, hence if they were capable of causing damage there, it would have already happened.

It sounds as if that is a solid argument.

(Indeed, a similar argument, but with neutron stars, may be the convincing argument about mini black holes not being a danger. That's what CERN is already telling people who email them, apparently. )

3. CERN is still promising to release their new safety report, any day now. I haven't spotted it yet.