AL's+Week+of+February+4

__2/4/08__ - So far I spent my class reading more on the particle adventures site and also listened to a discussion regarding the masses of particles and the quarks that make them up. Afterwards, I continued to read up on the particle adventures articles. one question I had during our discussion was //why// when something can happen in particle physics, it //will//. Strangely enough this question was addressed in the next particle adventure article on the site. The article, called [|If it can happen, it will]. On the page, the site describes how we can never actually know what a particle will do, only what it might do. We know where a particle might be, but not when it will be there. These particles are wave-like, so this is why we can't accuaretly pinpoint their location. To quote, " //This idea that// **//"if it can happen, it will happen!"//** //is fundamental to quantum mechanics. For some atoms there is a certain probability that it will undergo radioactive decay due to the possibility that the nucleus may --for the shortest of instants-- exist in a state that allows it to blow apart. You cannot predict when a particular atom will decay, but you can determine the// chance //that it will decay in a certain period of time.//"

__2/5/08__ - [|The next article] discusses half-lives and what it means to have a half-life. Essentially it measures the rate of decay of the nucleus of an atom. This is measured by how long it would take for half of a bunch of atoms to decay (a half-life). The decay of an individual atom is unpredictable, contrary to Einstein's statement that "God doesn't play dice!"

The next page read was [|the particle decay mediators article.] This article is about how fundamental particles decay into other fundamental particles. This is kind of hard to understand. Fundamental particles can't split apart, but tather they turn into other fundamental particles. They change into 1.) less massive particles and 2.) a force carrier particle. For example, a charm quark decays into a strange quark and a force-carrier particle which in turn decays into u and d quarks.

__2/6/08__ - [|These force carrier particles are also called virtual particles.] //A result of the// // Heisenberg Uncertainty principle// //is that these high-mass particles may come into being if they are incredibly short-lived. In a sense, they escape reality's notice.// //Virtual particles do not violate the conservation of energy. The kinetic energy plus mass of the initial decaying particle and the final decay products is equal. The virtual particles exist for such a short time that they can never be observed.// //Most particle processes are mediated by virtual-carrier particles. Examples include neutron beta decay, the production of charm particles, and the decay of an eta-c particle, all of which we will explore in depth soon.//