Good News and Bad News from the Large Hadron Collider

The good news: Despite their best efforts, the folks at CERN failed to produce a black hole that sucked the entire earth into it! That would have been cool. The bad news is for string theory. What might be one of the few empirical tests for that tangle of math and stuff seems to have come out negative. From CERN:

The CMS experiment at CERN's Large Hadron Collider (LHC) has completed a search for microscopic black holes produced in high-energy proton-proton collisions. No evidence for their production was found and their production has been excluded up to a black hole mass of 3.5-4.5 TeV (1012 electron volts) in a variety of theoretical models.

Microscopic black holes are predicted to exist in some theoretical models that attempt to unify General Relativity and Quantum Mechanics by postulating the existence of extra "curled-up" dimensions, in addition to the three familiar spatial dimensions. At the high energies of the Large Hadron Collider, such theories predict that particles may collide "closely enough" to be sensitive to these postulated extra dimensions. In such a case, the colliding particles could interact gravitationally with strengths similar to those of the other three fundamental forces - the Electromagnetic, Weak and Strong interactions. The two colliding particles might then form a microscopic black hole.

If it were so produced, a microscopic black hole would evaporate immediately, producing a distinctive spray of sub-atomic particles of normal matter. These would then be observed in the high-precision CMS detector that surrounds the LHC collision point. CMS has searched for such events amongst all the proton-proton collisions recorded during the 2010 LHC running at 7 TeV centre-of-mass energy (3.5 TeV per proton beam).

No experimental evidence for microscopic black holes has been found. This non-observation rules out the existence of microscopic black holes up to a mass of 3.5-4.5 TeV for a range of theoretical models that postulate extra dimensions.

The CMS results have been submitted for publication in the Physics Letters journal. CMS will take much more data next year when the LHC resumes running in early 2011 after a brief technical stop.

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(1012 electron volts)

There's something missing there.

By MadScientist (not verified) on 16 Dec 2010 #permalink

Yes, 1000 electron volts. Once it hits 2012 the Ancient Mayan Physicist prophecy will be fulfilled and we're all fucked.

What particles do you find at 42 electron volts? The Stupidon? Vogon? If you get several Vogons together, will they try to blow up the Earth?

By Birger Johansson (not verified) on 17 Dec 2010 #permalink

the particles at mass 42 eV are voltrons.

If I understand you correctly, you're saying:

These findings are non-supportive of string theory, but don't quite rise to the level of falsifying it.

Is that approximately right?

In which case:

What more is needed to falsify string theory to the point where it is no longer a serious contender?


What kind of findings could bring back string theory to a degree where it was worthy of more attention?

I don't have a horse in this race (layperson here), I'm just looking to stay up to date such that my beliefs about the nature of things comport with the best currently available facts and theories.

These findings do not support string theory but then very few people expected any support for string theory at these energies.

No experiment within reach can rule out all versions of string theory. For that reason it may not be accurate to call string theory a theory at all. It may be better to think of string theory as a collection of ideas and techniques that will aid in analyzing new physics once it is sighted.

ppnl: Doesn't your second paragraph constitute some sort of religious declaration?

We have no testable theory but we know it's true, and we now have prophecies to interpret it once it arrives, which we know it will... Hmmmm.