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Elementary Particles and the World of Planck Scale


Quantum Domain
Elementary Particles
Fundamental Interactions
Unifications, A Brief History of Physics
Quantum Field Theory
Gauge Theory and the Standard Model
Asymptotic Freedom
Quark Confinement
Grand Unified Theory (GUT)
Manifold, Vacuum Energy, Multiverse, and Eternal Inflation
Quantum Foam and Loop Quantum Gravity
Realm of Planck Scale

Quantum Domain

Quantum Domain Figure 15-01 shows the size of those systems, which are governed by the rules in quantum theory. The deterministic property of classical physics is replaced by uncertainty for objects of such small size. Only the probability of certain quantities and processes can be estimated in this domain. It starts from molecule with a size of about 10-7cm to the hypothetical entity of string and membrane, which has a size of only 10-33cm. The size of the macro-molecules varies, the length of DNA can be up to 10 cm in human chromosom; while the width of the base pair is only 2x10-7 cm. The diagram also shows a proton composed of two up quarks and one down quark. According to the superstrings theory, these quarks are string or string attached to a membrane at the scale of less than 10-33cm, which is called the Planck scale - the smallest meaningful size (see Realm of Planck Scale).

Figure 15-01 Quantum Domain

Details about the instruments to probe the elementary particle domain is presented in the appendix: "Particle Accelerators and Detectors". Table 15-01a shows the major discoveries of elementary particles over the last 100 years.

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