Particle collisions at the LHC pose no danger to Earth.
6 events · 2 assessments · 3 decisions
Reassessed confirmatory
Trigger: subclaim_change. The vacuum-decay subclaim (f278fd0d, held on a contradicts edge) received its first assessment: CONTRADICTED as a danger scenario (credence 0.05). This is confirmatory for the parent: the hazard channel the claim's verdict already treated as excluded in prose is now independently assessed and consistent. Materiality judgment: no status change warranted; VERIFIED stands. I refreshed the assessment to reflect the now-assessed dependency and raised verdict confidence 0.88 -> 0.90; credence 0.99 unchanged. No structural changes: decomposition already covers the three hazard channels, the cosmic-ray precedent, and the operational record, and no missing dependency surfaced. No web search needed: the change was internal and confirmatory, the claim is settled (importance 0.4, contestation low), so a light pass per §19. Backfilled the missing evaluations on all three named arguments (hazard-by-hazard exclusion: holds; cosmic-ray precedent: holds; operational track record: holds with caveats regarding latency-limited hazards), anchored to this verdict. No notification to dependent stewards: status unchanged, and a 0.02 confidence increase is not material to any dependent. Importance left at 0.4; marginal yield recorded low (0.05) since the claim is saturated.
Reassessed: still Verified
verdict confidence 0.88 → 0.90 · credence 0.99
No action needed
Trigger: subclaim_change. The subclaim "Survival of white dwarfs and neutron stars constrains TeV-scale black hole accretion rates" received its first assessment: SUPPORTED (confidence 0.85, credence 0.92), grounded in the peer-reviewed Giddings-Mangano analysis with no physics refutation found. Materiality judgment: this change is fully consistent with, and mildly reinforces, the parent claim's standing VERIFIED assessment (confidence 0.88), which already relied on exactly this astrophysical bound as the answer to the trapped-products objection to the cosmic-ray precedent. The caveats flagged in the subclaim's assessment (neutron-star magnetic screening, meaning white dwarfs carry the tightest bound; the modest sample of well-characterised white dwarfs) do not weaken the parent's verdict, because the parent rests on multiple independent lines: the hazard-by-hazard exclusions, the cosmic-ray precedent completed by this bound, and the direct operational track record since 2010. No status, confidence, or credence change is warranted; re-issuing an identical assessment would be churn. No structural change needed: the subclaim already sits in the correct argument grouping. No propagation: nothing material changed at this node, so dependents have nothing to re-judge. Change absorbed per §22.
Structured and assessed
First pass on newly onboarded claim. Decomposed into three named for-arguments: (1) Hazard-by-hazard exclusion, linking the existing claims "TeV-scale black holes produced at the LHC pose no significant risk" (REQUIRES) and "A high-energy particle collision could trigger the universe's vacuum to decay" (CONTRADICTS, this claim being the danger counterpart), plus a new strangelet-exclusion subclaim (Matcher confirmed novel); (2) Cosmic-ray precedent, with a new cosmic-ray-bombardment subclaim (novel per Matcher) and the existing white dwarf/neutron star constraint claim (SUPPORTS); (3) Operational track record, with a new observational subclaim (novel per Matcher). Deliberately did NOT attach the Hawking radiation claim here: that dispute is material to the black hole subclaim's page, not this parent, and the published safety case does not depend on it. All three arguments given written forms. Importance revised from extractor seed 0.6 to 0.4: publicly consulted and nominally existential, but settled in informed discourse. New subclaims scored low (0.15-0.25) as largely uncontested, leaving two as embedded stubs. Assessed VERIFIED (confidence 0.88, credence 0.99) on peer-reviewed safety analyses plus fifteen years of incident-free operation; canonical form left unchanged as it is short, neutral, and matches common usage. Note: assessment preceded full assessment of subclaims (bottom-up ordering is not a gate); will re-judge if the black hole or vacuum-decay subclaims settle contrary to expectation.
Assessed Verified
verdict confidence 0.88 · credence 0.99
The safety of Large Hadron Collider collisions rests on three independent lines of evidence, each documented in peer-reviewed analyses. First, every specific catastrophe scenario that has been proposed, microscopic black holes that fail to evaporate, conversion of ordinary matter by strangelets, and collision-triggered decay of the vacuum, has been examined in detail and excluded, principally in the 2008 report of the LHC Safety Assessment Group and in the accompanying study by Giddings and Mangano published in Physical Review D. Second, cosmic rays with energies well beyond those of LHC collisions have struck the Earth, the Sun, and denser bodies such as white dwarfs and neutron stars for billions of years; the continued existence of these objects shows that such collisions do not produce world-destroying outcomes, and the density of white dwarfs and neutron stars closes the one loophole in this comparison, namely that collider products move slowly enough to be captured rather than escaping into space. Third, the LHC has now operated since 2010, producing an enormous number of collisions at its design energies, with no harmful effect of any kind observed. Public controversy around 2008, including lawsuits seeking to halt the collider, centered on the possibility of stable micro black holes and on the fact that Hawking radiation has never been directly observed. The published safety case anticipated this objection and does not depend on Hawking evaporation; it relies instead on the astrophysical bounds above. A residual scholarly discussion concerns not any positive evidence of danger but how much confidence any theoretical safety analysis can warrant, since the probability of an error in the analysis itself exceeds the minuscule probabilities the analysis outputs. That point qualifies claims of absolute certainty rather than the practical conclusion, which the operational record now supports directly.
Claim entered the graph