THERMAL FUSION OF LIGHT NUCLEI



2H + 3H is the only game in town, and it seems just beyond reach.  There is an obvious fuel problem because deuterium exists as only 0.01% of natural hydrogen, and tritium is not found in nature.  It has to be made one nucleus at a time in a nuclear reactor by neutron capture on deuterium!  Note that the fuel of a fusion reactor is radioactive... tritium has a short half-life, 12 years.






MAGNETIC CONFINEMENT
INERTIAL CONFINEMENT

The two basic approaches to controlled fusion are magnetic confinement via tokamak-type designs, culminating to date in the international project called ITER, and inertial confinement via laser heating and compression of liquid drops or pellets, culminating currently in the so-called National Ignition Facility. Alas, progress in inertial confinement is largely kept secret because it intersects with weapons design. However, it is generally thought that the facility has no chance of reaching its design goals.  ITER construction is more than a decade behind its schedule, with enormous cost overruns, and it is also generally thought that the facility has very little chance of reaching even scaled-down design goals. Funding partners are increasingly likely to begin pulling out in significant numbers. Even if inertial or magnetic confinement achieved some notable success, which seems increasingly unlikely, it is virtually impossible that individual nations could afford to construct significant numbers of commercial power plants using that technology, because the costs would be orders of magnitude beyond all other currently-available power plant designs. ITER has seen almost continual huge setbacks since construction began in 2013, and is now more than a decade behind schedule, not expected to be completed until 2035!









So far, all known proposals to obtain electrical power from fusion reactions “look like a total bust.” Sabine Hossenfelder here explains how various fusion experiments in their publicity persistently misrepresent the power output versus power input. Fusion power is almost unique in its ability to attract enormous private funding, and so there are many new companies at any given time, each offering some surefire new approach that's "bound to work!" The whole concept of fusion power plants seems inherently paradoxical, because unlike every other kind of power plant, any fusion power plant would ITSELF need enormous electric power to operate!

“THE DEVIL IS IN THE DETAILS!”


Nuclear Weapons Designs
NUCLEAR PROCESSES IN THE COSMOS

Eddington (1882 - 1944)
Gamow (1904 - 1968)
von Weizsäcker (1912 - 2007)
Bethe (1906 - 2005)

The big puzzle: the universe consists of 75% H and 25% He (everything else is negligible). But two protons cannot be fused (2He does not exist), a proton and 4He cannot be fused (5B does not exist) and two helium nuclei cannot be fused (8Be does not exist). WHAT'S GOING ON?????


The universally-used astrophysical parameterization introduced by Gamow.

1 keV corresponds to 11.6 million Kelvin. The core temperature of our sun is 15 million Kelvin.


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