Preface
Nuclear reactions provide a virtually inexhaustible source of energy, which can be
harnessed in the process of either fusion of light elements (e.g., hydrogen isotopes)
or splitting heavy elements (e.g., uranium, plutonium, thorium, etc.). In both cases,
the total mass of the initial nuclei, M in , is larger than the total mass of the products,
M pr , of the nuclear reactions. Then, from the famous relation between the energy and
mass, E ¼ Mc
2 (where c is the speed of light), and the energy conservation law, the
energy ΔE ¼ (M in À M pr ) c
2 goes into the kinetic energy of the products of the
nuclear reactions. This is somewhat similar to what happens when we burn fossil
fuels, where, however, we operate with the energy of chemical bonds of fossil fuel.
The fusion process requires the rapprochement of nuclei to a really small distance.
Since the nuclei are positively charged, this is only possible when the initial kinetic
energy (temperature) of the nuclei is large enough to overcome the strong repulsive
electric force. Thus, nuclear fusion is only possible at large temperatures ~10
8 K
which correspond to ~10
4 eV, where eV is the energy/temperature unit widely used
in physics. This makes nuclear fusion to be very different from fission, where the
release of nuclear energy occurs in the processes of the interaction of the nucleon
with a neutron (having zero electric charge and, therefore, not subject to the electric
force) and can proceed even at the room temperature. The harnessing of nuclear
energy via the fusion process is a challenging endeavor. First, the fusion fuel must be
heated by an external energy source to a very high temperature to turn the fusion
reactions on. Secondly, the high temperature of the fuel can be maintained by the
release of nuclear energy only when the energy leakage from the fusion fuel is
relatively slow, or, as physicists usually say, energy “confinement” or thermal
insulation of the fusion fuel is good enough. Thus, again, we see that fusion is
similar to the process of burning fossil fuel, which usually occurs at an elevated
temperature maintained by the release of the chemical energy and the proper energy
confinement. Finally, the extremely high temperatures needed for fusion reactions
make it impossible to use any solid material-based furnace for the “confinement” of
the fusion fuel. This is in striking contrast to the “furnace” fired by fission or fossil
vii
Nuclear reactions provide a virtually inexhaustible source of energy, which can be
harnessed in the process of either fusion of light elements (e.g., hydrogen isotopes)
or splitting heavy elements (e.g., uranium, plutonium, thorium, etc.). In both cases,
the total mass of the initial nuclei, M in , is larger than the total mass of the products,
M pr , of the nuclear reactions. Then, from the famous relation between the energy and
mass, E ¼ Mc
2 (where c is the speed of light), and the energy conservation law, the
energy ΔE ¼ (M in À M pr ) c
2 goes into the kinetic energy of the products of the
nuclear reactions. This is somewhat similar to what happens when we burn fossil
fuels, where, however, we operate with the energy of chemical bonds of fossil fuel.
The fusion process requires the rapprochement of nuclei to a really small distance.
Since the nuclei are positively charged, this is only possible when the initial kinetic
energy (temperature) of the nuclei is large enough to overcome the strong repulsive
electric force. Thus, nuclear fusion is only possible at large temperatures ~10
8 K
which correspond to ~10
4 eV, where eV is the energy/temperature unit widely used
in physics. This makes nuclear fusion to be very different from fission, where the
release of nuclear energy occurs in the processes of the interaction of the nucleon
with a neutron (having zero electric charge and, therefore, not subject to the electric
force) and can proceed even at the room temperature. The harnessing of nuclear
energy via the fusion process is a challenging endeavor. First, the fusion fuel must be
heated by an external energy source to a very high temperature to turn the fusion
reactions on. Secondly, the high temperature of the fuel can be maintained by the
release of nuclear energy only when the energy leakage from the fusion fuel is
relatively slow, or, as physicists usually say, energy “confinement” or thermal
insulation of the fusion fuel is good enough. Thus, again, we see that fusion is
similar to the process of burning fossil fuel, which usually occurs at an elevated
temperature maintained by the release of the chemical energy and the proper energy
confinement. Finally, the extremely high temperatures needed for fusion reactions
make it impossible to use any solid material-based furnace for the “confinement” of
the fusion fuel. This is in striking contrast to the “furnace” fired by fission or fossil
vii