Appearing to Study Particle Physics, Part Three (blog version)

    I stormed into the den, throwing the library copy of Constructing Quarks across the room.  "I don't get it!"  I shouted.  "Even without all the math and chemistry crap it still doesn't make any sense."

    Dr. Jeremy Wraxtiorre walked calmly into the room and held up his hands defensively, admonishing, "Please, don't throw that book around so much!  It belongs to the library.  Here, abuse your copy of Mangled Doves--you own a copy of that!  What's got you all up in arms?"

    I walked across the room and picked up the book.  "I was babe-watching on the freeway today because it's not easy to pretend to read a book about particle physics while driving--it ranks right up there with Driving While Texting--and I couldn't understand the section on Super-Colliders.  Why were they so important to the study of physics if they do nothing more than take pictures of subatomic particles crashing into each other?"

     "If you are having trouble with the usefulness of Super-Colliders in the study of theoretical physics, then you're really not going to understand the upshot of the book's portrayal of their changing role in the development of the Quark Theories."  Dr. Wraxtiorre strolled around to the front of the sofa and sat down comfortably.  "You see, scientists study things that are outside of the realm of a laboratory by taking pictures of them, and then sitting around studying those pictures with their theories in mind trying to explain what is happening in the pictures.  When it comes to subatomic particles, you can't take pictures of them--but you can take pictures of the bubble-trails they leaves in a compressed-gas chamber; or you can take pictures of photodetectors lighting up when they are struck by subatomic particles.  This is what the early particle accelerators did, by generating a beam of protons or electrons, and racing them along a narrow pipe by turning rings of electromagnets on and off, so as to encourage the particles to race along in one direction or the other faster and faster in a slender beam, like a laser.  At a given point in this circular pipe is an opening with electromagnets which encourage the particles in the beam to race out of the ring into a bubble chamber or onto a plate covered with photodetectors.  Super-Colliders are made of two of these ringed pipes--usually stacked on top of each other--racing the beams in each pipe in opposite directions, and that opening in the two pipes is in the same spot, each pointed directly at the other.  The resulting collision produces twice the impact velocity as a particle accelerator."

    I set the book down on the coffeetable and stepped back towards a chair.  "Gee, Doc.  You seem to know a lot about this already.  You're more animated than I have seen you in several weeks.  But how do the theoretical physicists use these pictures to explain their theories?"

    "With the early particle accelerators, the theorists were able to prove that certain particles exist because the properties of the particles caused them to behave in different ways in the bubble chamber, and so the theorists could say that only certain properties would cause a particle to act in the way that a certain bubble-trail would indicate, and that those properties necessarily indicate a particular type of particle.  It's kinda like playing roulette, with balls of different weights and sizes.  A heavier ball will travel further, and so would land on a certain number which has a certain color, either red or black.  In the figure, if the ball were to fall where it is now, it would be black 29. A heavier particle would travel further, and might fall into the slot at red 9."

    I plopped myself into an easy chair beside the coffeetable and looked crossly at Dr. Wraxtiorre.  "So, theoretical physics is like gambling, and particle accelerators are like casinos?"

    Dr. Wraxtiorre shifted uncomfortably on the cushions of the sofa.  He chanted, "I am sofa king.  We Todd it."

    "What's gotten into you?  Are you making fun of me?"  I looked across at Dr. Wraxtiorre with puzzled eyes.  "Or, are you making fun of yourself, using that funky self-deprecating humor that you're so fond of?"

     "Sorry, I was just remembering an old YouTube video of that prank.  What were you saying?"

    I leaned forward and cupped my hands in front of me.  "You were comparing particle accelerators to roulette wheels, and when I suggested that theoretical physics might be like gambling and particle accelerators might be like casinos, you got all flaked out on me."

    Dr. Wraxtiorre straightened his back up and grimaced.  "Maybe it's because I find the comparison inappropriate.  Perhaps a different image will be more helpful.  When I was a child in the prewar years of the Great Depression, we used to play Marbles a lot.  It kept us outta trouble and taught us strategy, along with a little practical usage of physical laws.  If your firing marble went into the ring and hit another marble off-center, then it knocked the other marble out of the ring at an odd angle.  We called that 'putting English on it.'  People who play pool still use that phrase to describe it.  In a sense, Super-Colliders are a lot like the game of Marbles.  The two beams are accelerated in opposite directions, and then turned to ram into each other in front of a wall of photo-detectors. The physicists were able to tell which particles were which by their angle of deflection.  They also began to notice that there were particles in the pictures that they hadn't accounted for in previous pictures.  This, my friend, is where they had to start coming up with new theories."

    "Doc, you're getting that sparkle in your eye again.  Should I get you an Ice Cream bar and a bicycle? I mean, now you're beginning to make it sound like theoretical physics was like being a kid again."

    "Well, it some ways it is.  Haven't you ever gotten two toy cars and smashed them together?"

    I shrugged.  Shaking my head from side to side, I indicated that I had not.

    "You mean you never had a couple of toy cars that you were tired of looking at and just decided to smash them into each other out of sheer boredom, just to see what it would look like with all the pieces flying off in all directions, and the sound of the plastic bending, cracking and snapping?"

    I remained motionless.

    "Well, that's good because theoretical physicists are nothing like that.  All they got to do was recommend specific conditions that they wanted the people at the Super-Colliders to put in place for experiments for them, and go collect the data afterward.  It was the people at the Super-Colliders who were reliving their childhoods."

    I looked across to the kitchen for awhile, thinking about all the things that the doctor had just told me.  The dog trotted across the living room and sat down beside the driveway door, whimpering quietly.  He pawed at the door twice and looked at me, imploringly.  I got up, walked over to the door, and opened it to let the dog go outside.

    Dr. Wraxtiorre looked at me with perplexed eyes.  "So, you really never did that with your toy cars?"

     "Who would want to do that, Doctor?  Really, toy cars are much too important to want to destroy them.  Haven't you seen any of the Toy Story movies?"

This article has been published in the book, Appearing to Study Particle Physics, as "Super-Colliders and Casinos."  It is now available at Lulu.com