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May 6, 2014

Affirmation / ES Technical Note on LHC Collider Safety (p-p/MBH)

Posted by in categories: engineering, environmental, ethics, existential risks, particle physics

Although I have already mentioned a recent technical note on the application of Astronomical Observation to LHC/Collider Safety in comments to other posts here and there, I have not posted specifically about it until now. So finally, a short mention:

The technical note follows on from a modest paper I wrote in 2012 (Discussions on the Hypothesis that Cosmic Ray Exposure on Sirius B Negates Terrestrial MBH Concerns from Colliders), which concerned micro-black hole (MBH) production and the white dwarf safety assurance. There I demonstrated that not only are most white dwarf stars not suitable as a safety assurance, but that those hand-picked for the 2008 safety report had magnetic field strength measured to just 99% confidence within the range for safety assurance. That is not to say that the LHC safety argument was only 99% reliable — just that one of the cornerstone assurances was. The affirmation of these measurements was needed for a safety assurance to LHC p-p collisions based on astronomical observations – as a safety assurance that is not based on Hawking Radiation theory — but based on verifiable measurement. The technical note captures the official LSAG (CERN) response on the matter after internal review at CERN in late 2012, which had remained archived from email discussions until recently, when those conclusions were formalised into this technical note:

Link to the technical note: http://environmental-safety.webs.com/TechnicalNote-EnvSA01.pdf

mostly harmless

That conclusion was fortunately, as expected, one of safety: significant progress had been made on the accuracy of B field measurement technology since the original 2008 safety report — and after a survey of latest literature, one finds that there are now extensive examples of WD with fields measured with uncertainty ranges within the 1–100 kG range required for assurance. However — despite an eventual conclusion of safety on this one matter (MBH concerns from p-p collisions) I would like to reiterate a point that I made back in 2008, that there is an obligation on industry to keep safety debate open and honest. We are not likely to see credible argument on any of the other concerns to LHC operations (strangelet production, magnetic monopoles, de sitter space transitions and vacuum bubbles, and so on), but these discussions do illustrate that re-visitations can be necessary.

Whilst onwards we strive to find new understandings to the universe, and to engineer new ways of being, we need to stand back and take a look at where we are, lest we get lost.

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Comments — comments are now closed.


  1. Niccolò Tottoli says:

    Dear Tom

    On page 3 in your technical note, you say: “It is also noted that the LSAG 2008 safety report also contains a second safety assurance based on astronomical observation – based on the longevity of neutron stars. To date no paper has challenged this second safety assurance…”

    Such a paper exists, please start on page 59 here:
    http://www.lhcsafetyreview.org/docs/black-hole-review.pdf
    But many other details of the micro black hole risk are handled in the paper.

    Some more interesting papers, for example concerning the risks of false vacuum, black hole remnants and heavy ions:
    http://www.lhcsafetyreview.org/

    Thank you.

    Best regards

  2. Tom Kerwick says:

    Hi Niccolò.

    Thanks for the reminder. It seems Alam’s LHC safety review document is still in a ‘draft’ status, with many sections with editorial comments such as ‘full text pending’, ‘to add summary of factors’ and ‘text under revision’…

    However, his critique/analysis on the safety assurance of neutron stars seems quite reasoned and balanced. For example — he does state ‘it would seem reasonable to conclude that a neutron star could trap practically any black hole that reaches it’ — with most of the critique focusing specifically on magnetic screening and production rates.

    I would like to see him complete his paper — though it seems the last revision update was in 2010 — so I presume this is not likely to happen… In any case — I will add a reference to his paper on next update of the technical note.

    I must also add clarification to the technical note about MBH with D>=8 scenarios, as Alam points out — the neutron star safety assurance is more crucial for such.

    Kind Regards–
    –Tom.

  3. Niccolò Tottoli says:

    Dear Tom

    You say: “However, his critique/analysis on the safety assurance of neutron stars seems quite reasoned and balanced. For example — he does state ‘it would seem reasonable to conclude that a neutron star could trap practically any black hole that reaches it’ — with most of the critique focusing specifically on magnetic screening and production rates.”

    Yes, but only “…that reaches it” – if any.
    You are completely right that micro black hole production rates and the magnetic screening at neutron stars is very important.
    It is therefore possible that neutron stars only exist because usually not any micro black hole reaches them.

    If one carefully reads and counter checks the few pages of the neutron star section in Alam Rahman‘s black hole paper, it becomes clear how tricky the paper of Prof. Giddings and Prof. Mangano is — and more important: that it is impossible to promise safety by a neutron star argument when the collision energies are increased at the LHC.

    You said: “We are not likely to see credible argument on any of the other concerns to LHC operations (strangelet production, magnetic monopoles, de sitter space transitions and vacuum bubbles, and so on)…”

    Let us indeed not forget all the other risks which are insufficiently assessed in the LSAG safety report, let alone the various, not yet assessed risks (e.g. wormholes or man-made Big Bang).
    Concerning false vacuum decay, LSAG‘s only argument seems to be the cosmic ray argument, which is flawed because it is not known whether collisions between pairs of Pb or between ions with similar masses as Pb with LHC-design energy ever happened in the Universe.
    According to theories, Pb-Pb ion collisions could be more suitable to initiate such a vacuum decay, which would mean the destruction of the entire(!) Universe as we know it.

    In the RHIC safety report, page 4, it is said that: “While theory strongly suggests that any possibility for triggering vacuum instability requires substantially larger energy densities than RHIC will provide, it is difficult to give a compelling, unequivocal bound based on theoretical considerations alone.“
    Instead, they used the flawed cosmic ray argument too.
    Though the probability of a vacuum transition induced by collisions at the RHIC is calculated in their safety report, they also used cosmic ray estimations and extrapolations for high energy cosmic rays — instead of to include only observed cosmic ray data.
    Their probability calculation becomes even more dubious if we keep in mind that other factors of different theories could increase the risk. But again, a risk calculation based only on observed cosmic rays (including the CR fraction and species) would be a good thing to start with.
    We should note too, that there is no probability calculation of any risk in the LSAG report although the collisions at the LHC are much more energetic…

    For a vacuum transition, even if it might be ‘unlikely‘ (which we do not know), a risk formula would not only include the probability — whether it could happen — but the worst case damage factor too, which increases the risk dramatically..!
    Is the possible benefit of the LHC experiment really worth to risk the entire Universe?
    Who shall have the right to answer this question — scientists of CERN, everybody on Earth or all life in the Universe? Will we be allowed to ask our grandparents if all disappears?

    Thank you.
    Best regards
    Niccolò

  4. Tom Kerwick says:

    I’ve updated that technical note now (attached) to reference Alam’s paper -

    also updated here (remember to reload/refresh) -

    http://environmental-safety.webs.com/apps/blog/entries/show/…er-safety–
    http://environmental-safety.webs.com/TechnicalNote-EnvSA01.pdf

    Main changes on page 3 -

    Modified lines:

    “To date few have challenged this second safety assurance,”

    Added lines:

    “Most significant of such critical analyses are those published at the self-styled LHCSafetyReview.org,
    where draft documentation [8] discusses potential weaknesses in various safety assurances.”

    “However – the WD safety assurance is only valid for lower orders of dimensions of MBH [5], and
    column densities required to stop the heaviest black holes (D>=8) exceed the stopping power of WD.
    To cover scenarios of MBH with D>=8, further analysis is required on the NS safety assurances [5][8].”

    And added Alam’s paper as reference on page 6 —

    “[8] Black Hole Production at the LHC: A review of the Risks — Draft (Rev 0.03) (A. Rahman, 2010)
    http://www.lhcsafetyreview.org/docs/black-hole-review.pdf

    Thanks again for pointing out the oversight.

    Kind regards–
    Tom.