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LHC sets record, and we are still here.

Published on Nov 30, 2009 at 3:27 pm. 1 Comment.
Filed under physics.

According to a report on Science Daily, the Large Hadron Collider has set a new energy record. The twin beams were at an energy of 1.18 TeV, beating the 0.98 TeV energy of Fermilab’s Tevatron. That now makes the LHC the worlds most energetic particle collider. Despite all of the cries to the contrary, we are still here after this milestone. However, don’t expect all of the people crying that it is the end of the world to quiet down just yet. Next year, the LHC will work its way up to an energy of 3.5 TeV per beam, for a total collision energy of 7.0 TeV. Until it reaches that milestone, then the end-of-the-worlders will simply be telling us that the end is postponed. Then, once 7 TeV collisions become common, they’ll come up with some other explanation for why we are still here. The vast majority of physicists don’t have a problem with this collider. In fact, there are collisions at FAR higher energies than this occuring all of the time in the air over our heads. Galactic cosmic rays rain down on us at far higher energies than the LHC will ever be able to produce. In fact, it is not unheard of for galactic cosmic rays to have energies in excess of 100000000 TeV. Granted, the average cosmic ray energy is far lower than that, but the very high energy ones still occur, and they have done so for billions of years. None have destroyed Earth yet, so I don’t see any compelling reason to expect the LHC to do so, either.

Part of what makes this particle collider, and high energy physics in general, so confusing to the general public is the terminology. For one thing, the beam energy is often given in terms of electron volts (eV). An electron volt is the energy that it takes to move a charged particle having charge e (the fundamental charge, 1.602×10^-19 coulombs) through a potential of one volt. That turns out to be equal to 1.602×10^-19 Joules, a very tiny bit of energy. But, we are talking TeV here. What is that? TeV stands for tera electron volt. That is one trillion (10¹²) electron volts. That’s got to be a lot, right? Well for a subatomic particle, one TeV really is a lot. But, to give you the sort of idea of what kind of energy this is, imagine figuring out the amount of energy that it takes to lift a penny. If you lift the penny a distance of 0.045 mm (about 1/100 of an inch), then you have used about 7 TeV of energy.

It is hard to imagine how energy so small could scare anyone. Granted, some are worried about possibly the energy being confined to a small enough volume to create a miniature black hole. However, black holes that small would not be stable, so there would be little to worry about. I am not going to go into all of the reasons why such things are nothing to worry about. That’s been done before by many other writers on the internet. Black holes themselves are grossly misunderstood, and are not nearly as scary as science fiction writer portray them. Indeed, if miniature black holes really were a hazard to us, then we’d be doomed long before now due to the collisions from much higher energy cosmic rays. So, I am not worried that the LHC is going to destroy the world when it reaches full power.

-Astroprof

Image Credit: CERN