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Đây là bộ sách tiếng anh về chuyên ngành vật lý gồm các lý thuyết căn bản và lý liên quan đến công nghệ nano ,công nghệ vật liệu ,công nghệ vi điện tử,vật lý bán dẫn. Bộ sách này thích hợp cho những ai đam mê theo đuổi ngành vật lý và muốn tìm hiểu thế giới vũ trụ và hoạt độn ra sao.
[...]... distinct groups called the quarks and the leptons (at this stage don’t worry about where the names come from) Quarks and leptons are distinguished by the different ways in which they react to the fundamental forces There are six quarks and six leptons The six quarks are called up, down, strange, charm, bottom and top1 (in order of mass) The six leptons are 5 6 The standard model Table 1.1 The fundamental... as the proton and the neutron If the leptons could feel the strong force, then they would also bind together into particles This is the major difference between the properties of the quarks and leptons ➨ ➨ The leptons do not bind together to form particles The strong force between quarks means that they can only bind together to form particles The four fundamental forces 13 Current theories of the. .. circumstances; there are six different quarks and six different leptons; the quarks can be divided into three pairings called generations; the leptons can also be divided into three generations; the quarks feel the strong force, the leptons do not; both quarks and leptons feel the other three forces; the strong force binds quarks together into particles; the weak force can turn one fundamental particle into another—but... 1 The standard model This chapter is a brief summary of the theories discussed in the rest of this book The standard model of particle physics— the current state of knowledge about the structure of matter— is described and an introduction provided to the big bang theory of how the universe was created We shall spend the rest of the book exploring in detail the ideas presented in this chapter 1.1 The. .. of quarks into generations roughly follows the order in which they were discovered, but it has more to do with the way in which the quarks respond to the fundamental forces All the matter that we see in the universe is composed of atoms—hence protons and neutrons Therefore the most commonly found quarks in the universe are the up and down quarks The others are rather more massive (the mass of the quarks. .. they are linked in some way to the charged leptons The link is formed by the ways in which the leptons respond to one of the fundamental forces This allows us to group the leptons into generations as we did with the quarks Table 1.3 shows the lepton generations 10 The standard model Table 1.3 The grouping of leptons into generations (NB: the symbols in brackets are the standard abbreviations for the. .. force at all They are effectively blind to it (similarly a neutral object does not experience the electromagnetic force) This is the reason for the division of the material particles into the quarks and leptons ➨ ➨ Quarks feel the strong force, leptons do not Both quarks and leptons feel the other three forces This incredibly strong force acting between the quarks holds them together to form objects (particles)... mirrored in the muon and the tau Indeed, when the muon was first discovered a famous particle physicist was heard to remark ‘who ordered that?’ There is very little, besides mass, that distinguishes the electron from the muon and the tau They all have the same electrical charge and respond to the fundamental forces in the same way The only obvious difference is that the muon and the tau are allowed to decay... into other particles The electron is a stable object The fundamental particles of matter 9 Aside from making the number of leptons equal to the number of quarks, there seems to be no reason why the heavier leptons should exist The heavy quarks can be found in some exotic forms of matter and detailed theory requires that they exist—but there is no such apparent constraint on the leptons The heavy quarks. .. type to another The weak force is the reason for the generation structure of the quarks and leptons The weak force is felt by both quarks and leptons In this respect it is the same as the electromagnetic and gravitational forces— the strong force is the only one of the fundamental forces that is only felt by one class of material particle If two leptons come within range of the weak force, then it is . x0 y0 w1 h3" alt="" Quarks, Leptons and the Big Bang Second Edition Quarks, Leptons and the Big Bang Second Edition Jonathan Allday The King’s School, Canterbury Institute. In my case, Quarks, Leptons and the Big Bang was hauled round several publishers under the guise of a textbook for schools in England. All the time I knew