- real background
- faked background
- detector-induced background
He showed the structure of the detectors - such as the huge detector GEM - designed for the Superconducting SuperCollider (SSC) that has been stopped 10+ years ago. That was sad. We could have had a lot of data already. One of the clear lessons from the SSC is that the particle physicists should have voted for the Republicans at that time :-) - although the current correlation between the parties and the physics policies is less clear and might be, in fact, reverted.
Various quantities are measured with various large errors. These machines are not perfect and the Large Hadron Collider (LHC) won't be perfect either. In various directions, the detectors and calorimeters are insensitive because the wires and cooling and similar necessary things must go through somewhere. Moreover, GEM - as tall as a 7-story building and almost twice as long - was divided into two parts exactly in the middle. This is the most interesting point corresponding to zero rapidity where new physics is expected. Nevertheless, they planned that there would be a blind spot exactly at this place. It's like your brain that is divided into two hemispheres exactly in the middle.
Kenneth Lane said that the experimentalists who design these detectors spend a lot of time arguing about technology choices. For example, should they use liquid argon or crystals for an electromagnetic calorimeter? He thinks one of the rules that help them to find the right answer is that, if theorists like Lane have an opinion on the technology, then they are certainly wrong. Comparing the SSC and LHC detectors, Lane thinks the choices may not always matter as much as taste and politics -- there is a lot of money and power involved. However, all these decisions are done by smart people who have very rational, scientific arguments, he added. ;-)
Incidentally, Peter Woit on his educational low-dimensional blog Not Even Wrong tried to distort the image of Kenneth Lane. Peter has even tried to picture Kenneth Lane as a person who is not enthusiastic or even bitter about string theory! :-) In reality, when we were taking the standard visitor's photograph, Kenneth Lane insisted that he should be photographed with Edward Witten, Joe Polchinski, Andrew Strominger, and Cumrun Vafa as all of them celebrate 20 years of superstring theory. In fact, Kenneth Lane is on his way to the 21st Aspen Winter Conference and he wants to have a proof that he also celebrated the 20th anniversary of strings.
Although most of us at Harvard are very realistic and sometimes even frustrated by the relatively slow progress in our field, why should we inhibit the enthusiasm of Kenneth Lane for string theory? The pictures are here and here.
Acknowledgements: I am grateful to K.L. for improvements of this text.