The stakes are high, and win or lose, worth playing for. -Fred Hoyle
Yesterday was a record-setting day for humanity. Over at CERN, the Large Hadron Collider achieved a new record for the most energy ever created in a laboratory collision in the history of humanity: 7,000,000,000,000 electron Volts, or 7 TeV (Tera- or Trillion-electron-Volts) for short.
Sure, we get energies higher than this all the time from black holes, neutron stars, and other catastrophic processes in space. Occasionally, we even observe them, in the form of Cosmic Rays!
But there are two big differences between cosmic rays and collisions in an accelerator like this. First, cosmic rays are moving incredibly quickly with respect to the Earth, which is at rest! A cosmic ray striking the Earth is like a hollow-point bullet striking its target; the target suffers incredible damage not just at the point of impact, but all throughout it. In terms a physicist cares about, the energy gets distributed throughout the target, over a wide volume and over a huge number of particles.
In a collider, however, we can control this collision. We take a proton moving very close to the speed of light moving clockwise throughout the accelerator, and another proton moving very close to the speed of light moving counterclockwise throughout the accelerator! This is like shooting two bullets at the same speed directly at each other, and hitting them dead on! (Sorry for the low-res image below; it’s the best I could find!)
When this happens, the energy can nearly all go into producing new particles!
So that’s the first big advantage to having a collider. The second is that you can control where these collisions occur, and so you can choose a collision point and build a giant detector around it! What do I mean by “giant detector?” There are two. There’s the CMS detector (the “C” stands for Compact, believe it or not):
and the other one is the ATLAS detector, which is even bigger!
So you build these giant detectors around your collision points, and you track what comes out! If you record the right data, and you do your analysis properly, you can reconstruct what happened during the collision. This is a huge deal, because something spectacular happened at the LHC.
That 7 TeV collisions that took place yesterday were more than three times as powerful as the previous “world’s most powerful accelerator,” the Tevatron at Fermilab. After just a few months, the LHC will have more data at a higher energy than Fermilab has ever achieved over its entire existence! (And that means cumulative, since the 1970s!) This was a snapshot from the main control room at the LHC yesterday,
and this is what the tracks looked like from one of the very first 7 TeV collisions that took place there!
The Universe hasn’t seen consistent collisions at energies like this since it was just a few hundred microseconds old, or less than a second after the big bang!
What this means is that we have an opportunity to discover new, more energetic and more exotic particles that might exist in our Universe than ever before. Does the Higgs exist? We should know in just a few years. Do supersymmetric particles exist? If they do, the LHC should find them; if not now, than in about three years, after the upgrade to double its current energy: 14 TeV! Are there extra dimensions? If they’re relevant to our existence, we should find that out relatively soon, too!
So I’m curious to know what you think? Is the LHC likely to find any of these? Do you think that there are exciting possibilities (like technicolor, maybe?) that I missed that are worth exploring? Or will the LHC turn up nothing new at all, and force us to re-think how things as fundamental as mass work?