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Vivian O'Dell | USLHC | USA

View Blog | Read Bio

Life, The Universe, and Everything

I don’t think any real scientist would ever make a statement like “this is impossible”, or “this will never happen” — it is always “this is extremely unlikely”, with a qualifying “if current knowledge and theory holds”. It seems to be a fundamental property of science that we can never prove that something is true, but can only falsify hypotheses.

So, what is this “no conceivable danger” conclusion in the 22-page “Review of the Safety of LHC Collisions” November 2008 publication by the LHC Safety Assessment Group? How does one make any claims at all about what will not happen in an unexplored regime of experiment/theory?

The fine print that resolves the dilemma is that “unexplored regime” is not true. Homo sapiens may be patting ourselves on our backs for finally anticipating life at 10 TeV center-of-mass energy, but the universe has been ahead for some number of years equal to 1031 LHC experiments — and at a rate of 1013 LHC’s per second. Now we note that the universe still exists (as far as we can tell), planets and stars don’t spontaneously turn into black holes (as far as we can tell), and even the Earth has apparently survived 100 000 LHC-like experiments i.e. all those cosmic rays that the cosmos bestows upon us.

Could the 100 001-st time be particularly unlucky? It’s not impossible, but we probably have to work much harder to increase our ratings as a threat to reality.

This post was inspired by an interesting comment from a reader, who asked “when will the experiment finish?” After getting all excited about the lifetime of CMS and proposed Super-LHC upgrades — and hitting the “send” button — I suddenly realized that the concern was probably “hey, when will you stop gambling with all our lives?”, and not so much “hey, how long does a cool experiment like this take?”

I was going to mention that I believe politicians and military to be more active threats to humanity than the unbounded (but not unregulated) curiosity of scientists. But then, it can be argued that destroying an ecosystem is still a lesser crime than annihilating the planet and perhaps the universe too, while we’re at it.

  • egan

    >>> It seems to be a fundamental property of science that we can never prove that something is true

    I can prove that there is an infinity of prime numbers.

  • Didi Mousse

    All this talk of the LHC destroying everything is putting the cart before the horse. As a concerned environmentalist, I feel compelled to speak out to protect us all. What we really need to worry about is all the cosmic waste the LHC is going to spew out into the solar system. I mean, do you really want all those unidentified particles whizzing around our backyard? What if my aluminum hat doesn’t work against them? What if they screw up whale communication? Is a fundamentally new understanding of the universe really worth this?

    Besides all that, worrying about black holes is like rearranging the deck chairs on the Titanic. The Vogons are going to move in and screw things up totally long before we get on with destroying ourselves, no matter what the mice say. That said, in the meantime, please join me in working for a green cosmos, and most of all,

    * DON’T PANIC *

  • Hi Egan. That’s not a fact about science, that’s a fact about a logical axiom-based system called the natural numbers. Now don’t get me wrong, the natural numbers are very useful, and certainly rather, well, natural. But when we talk about certainties in science we’re talking about statements like:

    The sun will rise tomorrow.

    And that is a statement that we can support very strongly, citing both unfailingly reliable past experience and our strong understanding of the relationship between the earth’s rotation, momentum conservation, and the sun rising — but we can’t prove it.

  • B
  • Paul

    Talking about Life and the Universe. What is your position on the Antrhopic Principle? A controversial principle that allows explanation of some feature of the observed universe, by pointing out that did it not obtain we would not be here to be remarking on it. For example, if we ask why the universe began some fourteen thousand million years ago, the anthropic principle allows the answer that this is about the amount of time it takes for the physical and then chemical and biological complexity to develop, that ends up with persons capable of appreciating the age and asking the question (From answers.com) How would the LHC experiments support or disprove this principle?

  • Paul

    Here is another definition:
    The Anthropic Principle is the simple fact that we live in a universe set up to allow our existence. If the universe were any other way, we would not exist, and would hence be unable to make any observations.

  • Paul

    Gamma Ray Bursts are huge explosions in the Universe where a tremendous amount of energy is released and vanished in seconds. We are talking of billions of degrees hot. Now, just imagine GRB’s to be more frequent in our galaxy, how would this have affected life in our planet? How is the Antrhopic Principle related to the fact that we still here? I mean, intelligent sentient beings. It makes me wonder about the probability for a GRB to affect us in a negative way, exploding somewhere in our galaxy. If not, do you think that it is a coincidence that we are here talking about this or are we just lucky? The Anthropic Principle would help us argue that we are at a safe distance from GRB’s because of the current status of this planet, that is, a planet with intelligent beings. These explosions have the power to destroy life as we know it, yet they seem to be selective of the galaxies where they occur. Our Milky Way seems to lack the property needed to allow GRB’s. Coincidence? Anthropic Principle in Action?