" What has been presented here so far essentially is due to Stachowiak, [1]. To understand how then models are used in more detail one needs to distinguish from each other the various reference modes in which the investigator puts the model with respect to the original . The reference modes that perhaps are most important in computing are: (1) descriptive, i. e. , the model describes the original. If the deviation from model to original cannot be tolerated then the model has to be changed. Analysis models are in a descriptive reference mode to their originals. Hot Model Rikki (2) prescriptive, i. e. "

" While the preponderance of matter in the universe can be explained by saying that the universe just started out this way, this explanation strikes most physicists as inelegant. Furthermore, the Standard Model provides no mechanism to generate the cosmic inflation that is believed to have occurred at the beginning of the universe, a consequence of its omission of gravity. The Higgs boson, which is predicted by the Standard Model, has not been observed as of 2005 (though some phenomena were observed in the last days of the LEP collider that could be related to the Higgs; one of the reasons to build the LHC is that the increase in energy is expected to make the Higgs observable). The first experimental deviation from the Standard Model came in 1998, when Super-Kamiokande published results indicating neutrino oscillation. This implied the existence of non-zero neutrino masses since massless particles travel at the speed of light and so do not experience the passage of time. The Standard Model did not accommodate massive neutrinos, because it assumed the existence of only "left-handed" neutrinos, which have spin aligned counter-clockwise to their axis of motion. If neutrinos have non-zero mass, they necessarily travel slower than the speed of light. Hot Model Teenage Therefore, it would be possible to "overtake" a neutrino, choosing a reference frame in which its direction of motion is reversed without affecting its spin (making it right-handed). Since then, physicists have revised the Standard Model to allow neutrinos to have mass, which make up additional free parameters beyond the initial 19. "