A surprising opportunity to explore something new in chemistry and physics has emerged. In March 1989, electrochemists Martin Fleischmann and Stanley Pons, at the University of Utah, announced that they had "established a sustained nuclear fusion reaction" at room temperature. By nearly all accounts, the event was a fiasco. The fundamental reason was that the products of their experiments looked nothing like deuterium-deuterium (D+D) fusion.  

In the following weeks, Caltech chemist Nathan Lewis sharply criticized Fleischmann and Pons in a symposium, a press release, a one-man press conference at the American Physical Society meeting in Baltimore, Maryland, and during his oral presentation at the APS meeting. Despite Lewis' prominence in the media spotlight, he never published a peer-reviewed critique of the peer-reviewed Fleischmann-Pons papers, and for good reason. Lewis' critique of the Fleischmann-Pons experiment was based on wrong guesses and assumptions.

Richard Petrasso, a physicist at MIT, took Fleischmann and Pons to task for their claimed gamma-ray peak. Petrasso and the MIT team, after accusing Fleischmann and Pons of fraud in the Boston Herald, later published a sound and well-deserved peer-reviewed critique of what had become multiple versions of the claimed peak.

From this dubious beginning, to the surprise of many people, a new field of nuclear research has emerged: It offers unexplored opportunities for the scientific community. Data show that changes to atomic nuclei, including observed shifts in the abundance of isotopes, can occur without high-energy accelerators or nuclear reactors. For a century, this has been considered impossible. In hindsight, glimpses of the new phenomena were visible 27 years ago.

In October 1989, a workshop co-sponsored by the Electric Power Research Institute took place at the National Science Foundation headquarters, in Washington, D.C. Among the 50 scientists in attendance was the preeminent physicist Edward Teller. After hearing from scientists at the Lawrence Livermore National Laboratory and the Naval Research Laboratory who had observed isotopic shifts in room-temperature experiments, Teller concluded that nuclear effects were taking place. He even had a hunch about a possible mechanism, involving some sort of charge-neutral particle.

By October, tritium production and low-levels of neutrons in such experiments had been reported from a few reputable laboratories, including Los Alamos National Laboratory and the Bhabha Atomic Research Center in India. Moreover, BARC researchers observed that the tritium production and neutron emissions were temporally correlated. Outside reviewers selected by the Department of Energy and tasked with examining the worldwide claims included this data in a draft of their report. Before the document was finalized, however, they removed the tables containing that data.

In the early 1990s, several researchers in the field strongly favored neutron-based explanations for the phenomena. By the mid-1990s, a vocal contingent of scientists attempting to confirm Fleischmann and Pons' claims promoted the room-temperature fusion idea. Other scientists in the field, however, observed evidence—isotopic shifts and heavy-element transmutations—that pointed not to fusion but to some sort of neutron-induced reaction.  

In 1997, theorist Lewis Larsen looked at some of this data and noticed a similarity to elemental abundances he had learned about while a student in Subrahmanyan Chandrasekhar's astrophysics class at the University of Chicago. Larsen suspected that a neutronization process was occurring in low-energy nuclear reactions (LENR). Physicist Allan Widom joined Larsen's team in 2004, and in 2006 they published a theory in the European Physical Journal C - Particles and Fields.

The Widom-Larsen theory has nothing to do with fusion; the key steps are based on weak interactions and are consistent with existing physics. The theory explains how nuclear reactions can occur at or near room temperature through the creation of ultra-low-momentum neutrons and subsequent neutron-capture processes. Such neutrons, according to the theory, have a very large DeBroglie wavelength and therefore have a huge capture cross-section, explaining why so few neutrons are detected. Many-body collective quantum and electromagnetic effects are fundamental to Widom and Larsen's explanation for the energy required to create neutrons in LENR cells. Crucially, such reaction-rate calculations are based not on few-body interactions but on many-body interactions.

After 2006, the scientists who remained wedded to their belief in the idea of room-temperature fusion rejected the Widom-Larsen theory. A few of these fusion believers began making unsupported claims of commercially viable energy technologies.

Hidden in the confusion are many scientific reports, some of them published in respectable peer-reviewed journals, showing a wide variety of experimental evidence, including transmutations of elements. Reports also show that LENRs can produce local surface temperatures of 4,000-5,000 K and boil metals (palladium, nickel and tungsten) in small numbers of scattered microscopic sites on the surfaces of laboratory devices.

For nearly three decades, researchers in the field have not observed the emission of dangerous radiation. Heavy shielding has not been necessary. The Widom-Larsen theory offers a plausible explanation—localized conversion of gamma radiation to infrared radiation. The implication is that immense technological opportunities may exist if a practical source of energy can be developed from these laboratory curiosities.

Perhaps most surprising is that, in the formative years of atomic science in the early 20th century, some scientists reported inexplicable experimental evidence of elemental transmutations. In the 1910s and 1920s, this research was reported in popular newspapers and magazines, and papers were published in the top scientific journals of the day, including Physical Review, Science and Nature. The experiments, using relatively simple, low-energy benchtop apparatus, did not use radioactive sources so the results defied prevailing theory. Several researchers independently detected the production of the gases helium-4, neon, argon, and an as-yet-unidentified element of mass-3, which we now identify as tritium. Two of these researchers were Nobel laureates.

In 1966, physicist George Gamow wrote, "Let us hope that in a decade or two or, at least, just before the beginning of the 21st century, the present meager years of theoretical physics will come to an end in a burst of entirely new revolutionary ideas similar to those which heralded the beginning of the 20th century." LENR may very well be such an opportunity to explore new science.