" One attempt to address the first defect is known as grand unification. The so-called grand unified theories (GUTs) hypothesized that the SU(3), SU(2), and U(1) groups are actually subgroups of a single large symmetry group . At high energies (far beyond the reach of current experiments), the symmetry of the unifying group is preserved; at low energies, it reduces to SU(3)×SU(2)×U(1) by a process known as spontaneous symmetry breaking. The first theory of this kind was proposed in 1974 by Georgi and Glashow, using SU(5) as the unifying group. A distinguishing characteristic of these GUTs is that, unlike the Standard model, they predict the existence of proton decay. In 1999, the Super-Kamiokande neutrino observatory reported that it had not detected proton decay, establishing a lower limit on the proton half-life of 6. 7× 1032 years. Atlas Model Railroad Co This and other experiments have falsified numerous GUTs, including SU(5). Another effort to address the first defect has been to develop Preon models which attempt to set forth a substructure of more fundamental particles than those set forth in the Standard Model. "

" The production model immediately before the Model T was the Ford Model S [1], an upgraded version of the company's largest success to that point, the Model N. For some reason, the follow-on was the Model A and not the Model U. Characteristics The Ford Model T car was designed by Henry Ford, Childe Harolde Wills and two Hungarian emigrants named József Galamb and Jenő Farkas. The revolutionary Model T factory assembly line system was devised mostly by Charles E. Sorensen and Charles Lewis. 1 The Model T had 177 in³ (2. 9 L) 4 cylinder motor in a block producing 20 horsepower (15 kW) for a top speed of 45 mph (72 km/h). O Gauge Model Railroad Building The engine had side valves and 3 main bearings. Recent accounts credit the default-configuration Model T with fuel economy on the order of 25 to 30 miles per gallon. "