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3.7
Quantum mechanics and the weird world of super small particles in the universe
  
  In the previous section we outlined some of the greatest discoveries over the past two hundred years in relation to rules(consistent behaviour) and sub atomic matter. In particular, the discoveries of the early decades of the 20th century highlighted a different set of behaviour expected from the "ordered" world of Newtonian Physics.  
  However, it was in the development and ultimate success in mathematically trying to unify the discoveries of Einstein, Planck, Maxwell, Bohr and others during the 1920's that even greater discoveries were established- QED or Quantum ElectroDynamics.  
3.7.1 QED- Quantum ElectroDynamics explained
  QED, or Quantum ElectroDynamics first originated mathematically in 1926 when the British physicist P.A.M. Dirac laid the foundations for QED with his discovery of an equation describing the motion and spin of electrons that incorporated both the quantum theory and the theory of special relativity. Then in the late 1940's his theory was expanded and refined by Richard P. Feynman, Julian S. Schwinger, and Tomonaga Shin'ichiro.  
  In essence, QED is based on an idea similar to Plancks concept of "quanta" of energy being transferred between bodies. In the case of QED, the bodies are charged particles(e.g. electrons or positrons) and the exchanged particles are considered photons.  
  According to the theory, these photons are virtual; that is, they cannot be seen or detected in any way because their existence violates the conservation of energy and momentum. The particle exchange is merely the "force" of the interaction, because the interacting particles change their speed and direction of travel as they release or absorb the energy of a photon. Photons also can be emitted in a free state, in which case they may be observed. The interaction of two charged particles occurs in a series of processes of increasing complexity. In the simplest, only one virtual photon is involved; in a second-order process, there are two; and so forth.  
  Each subatomic process becomes computationally more difficult than the previous one, and there are an infinite number of processes. The QED theory, however, states that the more complex the process (i.e., the presence of additional virtual photons), the smaller the probability of its occurrence. For each level of complexity, a factor of (1/137)2 decreases the contribution of the process, and thus, after a few levels the contribution is negligible. This factor, symbolized by , is called the fine-structure constant and serves as a measure of the strength of the electromagnetic interaction. It equals e2/c, where e is the electron charge, is Planck's constant divided by 2, and c is the speed of light.  
3.7.2 QED- what is all the fuss?  
  The revolution of QED compared to any theory before it, was that it turned upside down the classical notion of the "force" being the "non-local" component and matter being the "real" component. Under Newton and the world in which we live, matter is considered the substance that is real, while it is forces that appear to be the "guiding hand."  
  The QED theory reversed that order with the mathematical proof of the exchange of virtual particles- that for the first time, something that is, can be transformed into something that we cannot measure.  
3.7.3 Quantum Mechanics- it gets even weirder  
  If grappling with "virtual" particles that appear and disappear from observation isn't difficult enough to fathom, then the insights that were gained when the quantum theory was applied to analyze the "behaviour" of sub atomic particles is even weirder.  
  Quantum mechanics essentially deals with the behaviour of matter and light on the atomic and subatomic scale. It attempts to describe and account for the properties of molecules and atoms and their constituents--electrons, protons, neutrons, and particles such as quarks. These properties include the interactions of the particles with one another and with electromagnetic radiation (i.e., light, X rays, and gamma rays).
  
  When quantum mechanics is put into practice, say on an experiment of passing a beam of electrons through a set of pieces of paper with defines holes to observe the effect, it became clear that such objects as electrons cannot be strictly described from observation as either a particle or a wave, because both types of behaviour are present.  
  However, an even greater mystery was discovered when considering the principles of measurement to such observations. An essential feature of quantum mechanics is that it is generally impossible, even in principle, to measure a system without disturbing it; the detailed nature of this disturbance and the exact point at which it occurs are obscure and controversial.  
  To put it simply, a scientist may set up the same experiment with sub atomic particles again and again, but the certainty of outcome is only "possibilities" until the act of observation, when one will emerge influenced in part by the very act of observing(awareness).  
   
 
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