Ballotechnics is a speculative, controversial field of nuclear physics that studies ballotechnic nuclear reactions. A ballotechnic reaction occurs when a high-energy nuclear isomer makes a transition to a ground state, releasing gamma rays but no beta or alpha rays. Alpha and beta rays are actually bits of a nucleus, while gamma rays are pure electromagnetic energy. Because no matter is released in a ballotechnic nuclear reaction, but only energy, the substance itself does not experience a change in mass.
In a high-energy nuclear isomer, protons or neutrons in the nucleus are in an excited state, and the affected particles must undergo a change in spin to release their excess energy. Isomers can be induced to release this energy, but not all at once - there is no known chain reaction that could cause the immediate release of the isomeric energy. Many speculators without training in nuclear physics have suggested scientifically dubious ways that it can, leading to some labeling the entire field of ballotechnics as pseudoscientific.
Carl Collins of the University of Texas at Dallas claimed to induce gamma release in a nuclear isomer in 1991, but his results have never been duplicated, a strong indicator that his particular method is false. This incident has cast a shadow on the field of ballotechnics in general. The term ballotechnics was popularized by the inventor of the neutron bomb, Samuel Cohen, who probably also coined the term. The field is so obscure that very few papers on ballotechnics can be found, and there is certainly no physicist who has based his or her career around the field.
However, nuclear isomers are a reality. There are at least five stable isomers, including tantalum-180m, osmium-187m, platinum-186m, hafnium-178m, and zinc-66m. The "m" after the atomic number labels the element as an isomer.
Tantalum-180m can be found in tiny quantities within tantalum-180, and happens to be the most expensive substance on earth, with a cost of 17 million US dollars (USD) per gram! The world's supply of Tantalum-180m is only around seven milligrams. Tantalum-180m is also the only known metastable isomer with a half-life longer than a few decades. Other isomers have half-lives as short as a few days or even hours.
Ballotechnics received attention during the Cold War era because people feared that it could be exploited to create nuclear weapons or serve as a fissionless detonator for a fusion bomb. A shadowy substance known as "red mercury" was said to have been the subject of nuclear weapon research by Soviet Russia, and the material is said to have gone for 100,000 to 200,000 USD per gram. It is speculated that red mercury was one of the stable nuclear isomers.
Calculations suggest that a kilogram of pure Tantalum-180m has as much as 900 megajoules of energy stored in the excited states of its nucleons, which would make it an excellent power source if it could be induced to release that energy.