by Brian Greene
——. Dreams of a Final Theory. New York: Pantheon, 1992.
Wheeler, John A. A Journey into Gravity and Spacetime. New York: Scientific American Library, 1990.
Family 1
Family 2
Family 3
Particle
Mass
Particle
Mass
Particle
Mass
Electron
.00054
Muon
.11
Tau
1.9
Electron-neutrino
< 10-8
Muon-neutrino
< .0003
Tau-neutrino
< .033
Up-quark
.0047
Charm Quark
1.6
Top Quark
189
Down-quark
.0074
Strange Quark
.16
Bottom Quark
5.2
Table 1.1 The three families of fundamental particles and their masses (in multiples of the proton mass). The values of the neutrino masses have so far eluded experimental determination.
Force
Force particle
Mass
Strong
Gluon
0
Electromagnetic
Photon
0
Weak
Weak gauge bosons
86, 97
Gravity
Graviton
0
Table 1.2 The four forces of nature, together with their associated force particles and their masses in multiples of the proton mass. (The weak force particles come in varieties with the two possible masses listed. Theoretical studies show that the graviton should be massless.)
Vibration number
Winding number
Total energy
1
1
1/10 + 10 = 10.1
1
2
1/10 + 20 = 20.1
1
3
1/10 + 30 = 30.1
1
4
1/10 + 40 = 40.1
2
1
2/10 + 10 = 10.2
2
2
2/10 + 20 = 20.2
2
3
2/10 + 30 = 30.2
2
4
2/10 + 40 = 40.2
3
1
3/10 + 10 = 10.3
3
2
3/10 + 20 = 20.3
3
3
3/10 + 30 = 30.3
3
4
3/10 + 40 = 40.3
4
1
4/10 + 10 = 10.4
4
2
4/10 + 20 = 20.4
4
3
4/10 + 30 = 30.4
4
4
4/10 + 40 = 40.4
Table 10.1
Sample vibration and winding configurations of a string moving in a universe shown in Figure 10.3, with radius R = 10. The vibration energies contribute in multiples of 1/10 and the winding energies contribute in multiples of 10, yielding the total energies listed. The energy unit is the Planck energy, so for example, 10.1 in the last column means 10.1 times the Planck energy.
Vibration number
Winding number
Total energy
1
1
10 + 1/10 = 10.1
1
2
10 + 2/10 = 10.2
1
3
10 + 3/10 = 10.3
1
4
10 + 4/10 = 10.4
2
1
20 + 1/10 = 20.1
2
2
20 + 2/10 = 20.2
2
3
20 + 3/10 = 20.3
2
4
20 + 4/10 = 20.4
3
1
30 + 1/10 = 30.1
3
2
30 + 2/10 = 30.2
3
3
30 + 3/10 = 30.3
3
4
30 + 4/10 = 30.4
4
1
40 + 1/10 = 40.1
4
2
40 + 2/10 = 40.2
4
3
40 + 3/10 = 40.3
4
4
40 + 4/10 = 40.4
Table 10.2
As in Table 10.1, except that the radius is now taken to be 1/10.
