I'd agree that certain worlds would have the building of the LHC pushed back or moved forward, but I doubt there would be many where the LHC was just never built. Unless human psychology is expected to be that different from world to world?

...As I pointed out recently in another context, humans have existed for tens of thousands of years or more. Even civilization existed for millenia before obvious freak Isaac Newton started modern science. Your position is a contender for the nuttiest I've read today.

Possibly it could be made better by dropping this talk of worlds and focusing on possible observers, given the rise in population. But that just reminds me that we likely don't understand anthropics well enough to make any definite pronouncements.

How Many LHC Failures Is Too Many?

by Eliezer Yudkowsky 1 min read20th Sep 2008139 comments


Recently the Large Hadron Collider was damaged by a mechanical failure.  This requires the collider to be warmed up, repaired, and then cooled down again, so we're looking at a two-month delay.

Inevitably, many commenters said, "Anthropic principle!  If the LHC had worked, it would have produced a black hole or strangelet or vacuum failure, and we wouldn't be here!"

This remark may be somewhat premature, since I don't think we're yet at the point in time when the LHC would have started producing collisions if not for this malfunction.  However, a few weeks(?) from now, the "Anthropic!" hypothesis will start to make sense, assuming it can make sense at all.  (Does this mean we can foresee executing a future probability update, but can't go ahead and update now?)

As you know, I don't spend much time worrying about the Large Hadron Collider when I've got much larger existential-risk-fish to fry.  However, there's an exercise in probability theory (which I first picked up from E.T. Jaynes) along the lines of, "How many times does a coin have to come up heads before you believe the coin is fixed?"  This tells you how low your prior probability is for the hypothesis.  If a coin comes up heads only twice, that's definitely not a good reason to believe it's fixed, unless you already suspected from the beginning.  But if it comes up heads 100 times, it's taking you too long to notice.

So - taking into account the previous cancellation of the Superconducting Supercollider (SSC) - how many times does the LHC have to fail before you'll start considering an anthropic explanation?  10?  20?  50?

After observing empirically that the LHC had failed 100 times in a row, would you endorse a policy of keeping the LHC powered up, but trying to fire it again only in the event of, say, nuclear terrorism or a global economic crash?