THERMAL FUSION OF LIGHT NUCLEI

The often-quoted Lawson criterion is a scam in itself. It is simply the condition in which heat supplied directly to the material equals the heat released by fusion. But this has nothing to do with realistic considerations. Because of necessary inefficiency the heat supplied is just a fraction of the total heat paid for, and the cost of the system providing the heat is not considered, nor is the cost of maintaining the fusion conditions indefinitely... which would require an entire power plant just dedicated to that use. A commercial fusion reactor would have to run continuously, the whole idea of maintaining the plasma for a finite short time is nonsensical! Since most of the KE released in fusion is carried by neutrons, one has the additional problem of figuring out how to boil water with neutrons!


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! [The current record (2025) for holding plasma in a tokomak is about 20 minutes.]








Cross section of measured turbulence in a tokomak

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!  That is, located near each fusion power plant would have to be a huge conventional power plant, to provide electricity for the fusion reactor system.  What kind of plant would that extra plant be?  And given the costs and enormous construction time required by ITER, even if it should barely work, how could any state or large community afford to build a practical fusion power plant?

“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 by mass (everything else is negligible). But two protons cannot be fused (2He does not exist), a proton and 4He cannot be fused (5Li 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.  At these energies, nuclear processes are hidden behind the wall... the Coulomb barrier, and the corresponding cross sections are incredibly tiny.  It is a terrific challenge to obtain the total cross sections as a function of energy from direct experiments in the lab!


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