When Ernest Sternglass walked up the steps at 112 Mercer Street in April 1947, he knew it would not be a normal day. Like a church deacon summoned to meet the Pope, Sternglass—a 23-year-old researcher at the Naval Ordnance Laboratory in Washington, D.C.—had arrived in Princeton, N.J., at the invitation of its most renowned resident, Albert Einstein. Having completed only a bachelor’s degree in electrical engineering, he had written to Einstein earlier that month about the work he was doing in his lab. To his great surprise, not only did Einstein promptly write back, he requested that Sternglass visit Princeton to discuss the work in person.
What Sternglass didn’t know is that his visit to Einstein would set off a chain of correspondence, involving both an unpublished experiment (his) and an unpublished hypothesis (Einstein’s) that together may constitute one of the century’s most important disregarded pieces of science. The reason why the science was overlooked is plain enough: It was at least a generation ahead of its time. Now, more than half a century later, the work is being re-examined, with potentially profound implications for sustainable energy production. For Sternglass was to discover how to create free neutrons with household wall socket evergy levels—and Einstein was to explain why.
On that spring day in 1947, though, Sternglass was a humble visitor to the St. Peter’s Basilica of physics. Having arrived in Princeton, he knocked on the door of the clapboard house, was let into the foyer by a secretary, and was soon confronted with the now-famous silhouette: an elderly man with a frizzy-haired halo, wearing an old sweat suit and bedroom slippers.
Sternglass had contacted Einstein because his lab in Washington was investigating how electrons are ejected from a metal when hit by a beam of electrons. The Navy wanted to understand this process better so they could develop night vision cameras, photography, and video that would be sensitive to the infrared light given off by body heat.
The reason why the science was overlooked is plain enough: It was at least a generation ahead of its time.
At first blush, Sternglass’ findings might seem like just a military curiosity, hardly worthy of reaching out to the architect of space-time itself. But Einstein had won his Nobel Prize for a theory explaining a phenomenon related to the Navy research: the ejection of electrons from a metal illuminated by a beam of ultraviolet light, a process called the photoelectric effect. Sternglass had begun to suspect that the theory that explained his process—called secondary electron emission—was simply wrong. “Here I was, in my early 20s,” Sternglass writes in his 1997 memoir Before the Big Bang, “without any advanced education in physics, about to ask the most renowned scientist in the world since Newton what he thought about my ideas.”
The two, at Einstein’s invitation, walked out to the backyard at 112 Mercer Street. Einstein cherished the opportunity to stroll with guests through his modest but beloved gardens. Sternglass found a point of commonality with his host. “We had a small garden in the suburb of Berlin where my father had built a summer home,” Sternglass recalls. Both men were also native Jewish Germans who had escaped Nazi Germany in the 1930s, when there was still a chance to flee. Einstein cancelled his appointments for the rest of the afternoon.
Sternglass explained to Einstein how the latest theory of secondary electron emission was, ironically, too much like Einstein’s own model of the photoelectric effect. Einstein’s photoelectric theory considered just the outermost electrons in an atom, furthest from the nucleus. This was a safe assumption, and one borne out by today’s science. But an electron and a photon are different things. Electrons can pack more of a punch than UV light, and therefore can penetrate deeper into the atom. So every electron orbiting the atom has to be accounted for in a realistic theory of secondary electron emission, Sternglass said. “That sounds reasonable to me,” was Einstein’s reply.
The conversation moved on to something near to Sternglass’ heart: nuclear particles, and in particular, the neutron. Neutrons are agents of transmutation: They can transform one element of the periodic table into another. It was known at the time that the proton and neutron, which sit snugly next to each other in an atom’s nucleus, could transform into one another if paired with an electron. In this way, one could add a neutron to a stable isotope of carbon (with, say, six protons and seven neutrons in its nucleus) to create the unstable isotope, carbon-14, which has six protons and eight neutrons. After a while (on average 5,730 years), carbon-14 spits out an electron to make a stable isotope of nitrogen, with seven protons and seven neutrons. Here, then, was another connection to Einstein: Isaac Newton, whose laws of physics Einstein showed to be incomplete, was obsessed with the transmutation of elements (a part of the ancient tradition of alchemy), and kept one of the largest alchemical libraries of his time.
Sternglass had worked with Einstein’s theory of relativity, and had arrived at solutions to its equations that depicted stable, orbiting configurations of an electron and its antimatter counterpart, the positron. He interpreted these orbiting pairs as being equivalent to protons and neutrons. Today we understand these models to be creatively fascinating, but also incorrect (quarks make up protons and neutrons).
Nevertheless, it led Sternglass toward a crucial hypothesis. If neutrons and protons are indeed nuclear cousins differing in their makeup by just one electron, as Sternglass’ model suggested, then there could be a backdoor way of making neutrons out of protons and electrons. Einstein, too, had been wrestling with the nature of the electron, which leaves behind just two photons after colliding with its antimatter counterpart, and not a bestiary of particles like the one resulting from a proton-neutron collision. Was the electron a breed apart?
Within a few years, Sternglass would be colliding electrons with protons at energies too low to be considered interesting, and reporting some surprising results back to his mentor in Princeton. Einstein, for his part, saw promise in the young engineer. His parting advice was surprising: “Don’t do what I have done,” Einstein told Sternglass. “Always keep a cobbler’s job where you can get up in the morning and face yourself that you are doing something useful. Nobody can be a genius and solve the problems of the universe every day.”
Sternglass heeded the advice. Rather than enrolling in a pure physics graduate program, he entered the Ph.D. program in the new department of engineering physics, at his undergraduate alma mater, Cornell University. His graduate advisor was a Manhattan Project veteran, Phillip Morrison, who shared an office with another bomb veteran, Richard Feynman. Morrison told Sternglass he could run his neutron experiments so long as Sternglass also worked on the rather more conventional topic of secondary electron emission. Sternglass agreed.
On Nov. 19, 1950, Sternglass wrote a letter to Einstein telling him of his latest work. The letter—today in the Einstein Archives in Jerusalem—reveals an eager young physicist who was clearly waiting for the right moment to reconnect with a special correspondent. “I have been fortunate to be able to solve the secondary emission problem,” Sternglass wrote. “Since you were one of the first to encourage me in my approach, I felt I wanted to tell you very briefly what I found.” Thus resumed the correspondence between master and student.
Once Sternglass had a firm footing on the secondary electron emission problem, he turned his attention toward the ideas about neutrons and electrons he’d discussed with Einstein. And he wrote to his mentor as soon as he had experimental results he felt confident in.
In a letter to Einstein dated Aug. 26, 1951, Sternglass wrote, “You may be interested to learn that in the course of the past two months, I have been able to obtain experimental evidence for the formation of neutrons from protons and electrons in high-voltage hydrogen discharge.”
Neutron transmutation could in principle produce precious metals—the wild dream of medieval alchemists.
Sternglass’ neutron experiment consisted of an evacuated glass tube less than a foot long filled with hydrogen gas. He fired an electron gun, not unlike the type found in old tube TV sets, through the gas and at thin foils of silver and indium at the end of the tube. There was no known way that an electron beam of the energies he was studying (about 35,000 electron Volts) could have induced any radioactivity in the foils. Nevertheless, time and again, that is what he observed. When he ran a control experiment with the beam passing through regular air, the foils did not become radioactive.
The radioactive signature suggested that the two stable isotopes that make up silver (silver-107 with 60 neutrons and silver-109 with 62 neutrons) were undergoing transmutation. Adding a neutron to each would produce silver-108 and silver-110 isotopes, which are unstable. When silver-108 decays, it gives off an electron (or beta particle) in, on average, 2.3 minutes. The leftover atom becomes the stable isotope cadmium-108. Silver-110 is more short-lived, beta decaying into cadmium-110 in just 24 seconds. “I should expect to observe a decay lasting of the order of 3-4 minutes,” Sternglass wrote in his lab notebook. He’d seen just that. His silver foil was acting precisely as if it’d been bombarded by low-energy neutrons.
But this flew in the face of conventional models of particle and nuclear physics. Electron beams may glance off silver atoms in a metal foil. They may, as Sternglass himself had studied, knock other electrons out of a silver atom. However, the electrons in Sternglass’ tube, propelled by just 35,000 Volts, were moving far too slowly to yield any nuclear reactions. Einstein pointed out to Sternglass in a letter dated just four days later, “In order to form a neutron, an electron is needed that has passed through 780,000 Volts.”
A low-energy neutron source, Sternglass knew, could have dramatic implications. In 1951, the world’s top neutron production factory was a billion-dollar plant at the Atomic Energy Commission’s facilities in Hanford, Wash. But Sternglass seemed to be producing neutrons with an experimental setup costing just thousands of dollars. Once produced, these free neutrons could act as a kind of “philosopher’s stone.” They could, for example, create plutonium atoms from uranium. In fact they could theoretically transmute any element in the universe.
Neutron transmutation could in principle produce precious metals—the wild dream of medieval alchemists. But the cost to do so would be prohibitive. Today, though, a different and more alluring goal beckons: clean energy. The result of a transmutation would often be an unstable atom, fated to decay. In doing so, it would emit an energetic electron or photon. If this energetic particle could be captured, it might be transformed to heat—and usable energy.
In 1951, Sternglass recorded only preliminary thoughts about applications for his apparent discovery. “What I found [might] be of great interest,” Sternglass wrote in his unpublished lab notebook. “One would have a ridiculously simple neutron formation process—which might even be used in atomic energy applications.”
Whatever the future held, Sternglass was ecstatic. Halfway through the first night’s data collection, he called his wife, and the Cornell physics professor who built his experiment’s X-ray tube, Lyman Parratt. Once he got home, he also called Morrison, who said he doubted that low-energy neutrons could have been involved. So throughout the rest of July, Sternglass refined his experiment and continued to collect data. He revamped the gas pump system in his tube, re-ran part of his experiment at the bottom of a salt mine to exclude cosmic rays, and studied alternate theories. Everything pointed to neutrons. The scientific literature, too, seemed to support him. J.J. Thomson—Nobel Prize-winning discoverer of the electron—had reported a similar finding in 1914. “He observed a radiation emitted from platinum,” Sternglass wrote in his notebook, “… which I now believe is beta emission under the influence of neutron bombardment!”
Radioactive decay can be transformed into a bath of innocuous heat. And of course heat energy can readily be converted into electricity.
Interest in Sternglass’ result in the Cornell physics department was mixed with scandal. One faculty member told him that he’d heard rumors that Sternglass was faking his data. Later in the fall, Sternglass recorded another blunt exchange. “Talking to Prof. ––– yesterday made me feel rather upset,” Sternglass wrote. “He said that ‘even granted that there might be some effect noticeable in my data, he would not be interested in it.’ … And that there were many ‘queer experiments’ in the history of physics which no one could explain … It struck me that this was certainly a strange scientific attitude,” Sternglass continued.
Einstein, though, was more thoughtful. In just one brief paragraph in a letter dated Aug. 30, 1951, Einstein wrote two sentences that were as insightful as any idea he had formulated in his postwar years at Princeton. “Perhaps reactions occur in which multiple electrons simultaneously transfer energy to one proton,” Einstein wrote (his emphasis). “According to quantum theory, this is somewhat conceivable, although not probable.” What Einstein had suggested to Sternglass involved ensembles of electrons behaving collectively as one entity with shared attributes. Think of it as a group of kids pooling their pocket change to buy one candy bar. Today everything from superconductors to lasers relies on the collective behavior of electrons, but in the 1950s this was largely a distant and theoretical prospect.
Einstein had made a characteristically brilliant leap. But neither he nor Sternglass nor indeed any contemporaries had either the technology or the theoretical framework to make sense of Sternglass’ data. Neither his data, nor Einstein’s supposition, were published. Sternglass already had a thesis subject: secondary electron emission, a topic that ruffled no feathers. As Sternglass describes it in Before the Big Bang, he did re-run his neutron creation experiment nine years later when he was working at Westinghouse Research Laboratories. By then, however, Einstein had died. And using Westinghouse’s lab facilities, Sternglass couldn’t replicate his Cornell data (though it is worth pointing out that a colleague of his at the Naval Ordnance Laboratory had been able to reproduce his data in 1953). “To this day, just exactly how neutrons can be formed at much lower energies than expected in the complex environment of a gas-discharge tube remains a mystery,” Sternglass concludes in his 1997 book.
That could have been the end of the story. But, in an unexpected convergence, a completely independent line of research begun 25 years ago has resurrected interest in Sternglass’ low-energy neutrons. In 1989, two chemists at the University of Utah caused a worldwide media storm when they announced at a press conference that they’d invented a method of sparking nuclear fusion in a simple, tabletop apparatus. Stanley Pons and Martin Fleischmann had found that running electric current through a specially prepared palladium electrode immersed in heavy water produced copious amounts of heat, more than what would be expected from a chemical reaction. “Cold fusion,” the headlines blared.
But physicists then responded much as they do today: Cold fusion is simply a non-starter. There was none of the radioactivity, gamma rays, or high-energy neutrons that are expected to accompany a fusion reaction. What, then, could explain the data? As cold fusion became a pariah field, a few made the connection to low-energy neutrons. In May of 1989, just one month after Pons and Fleischmann published their data, someone named Larry A. Hull wrote a letter to the editor of Chemical & Engineering News speculating that they may have been observing not fusion but transmutation, brought about by the same low-energy neutrons that Sternglass had claimed to observe.
This interpretation lay on the periphery of the cold fusion research community (which was itself on the periphery of the broader scientific community) for more than a decade. It was only in 2006, with the publication of a landmark paper in the European Journal of Physics C, that neutron-induced transmutations, as something distinct from cold fusion, began to emerge as a viable theory. The paper predicts that electrons on a metal surface coated with hydrogen, deuterium, or tritium atoms can behave collectively (as Einstein had predicted) when driven by an oscillating electromagnetic field at a particular frequency. This collective behavior can give them enough energy to combine with the hydrogen, deuterium, or tritium to make neutrons.
The paper goes on to say that the resulting neutrons travel very slowly—slow enough, in fact, to get gobbled up by a nearby atom before they can even leave the microscopic vicinity of their birthplace. The atom then becomes unstable and might burp out radioactive decay byproducts like a gamma ray or energetic electron. A separate paper by the same authors calculates that microscopic surfaces of electrodes, like those that tend to produce low-energy neutrons, are efficient absorbers of radioactive gamma rays. So radioactive decay can be transformed into a bath of innocuous heat. And of course heat energy can readily be converted into electricity.
The above picture does not involve fusion, which would require blazing energies on the scale of the so-called “strong force” which holds together neutrons and protons. Instead, it requires lower energies on the scale of the nuclear weak force, which mediates the capture of an electron by a proton.
The papers’ authors—Northeastern University physics professor Allan Widom and Chicago-based energy industry consultant Lewis Larsen—developed their ideas independently of the unpublished Stern- glass-Einstein work. Although both Widom and Larsen declined interview requests for this story, both have separately noted that it was only after their paper’s publication that they ran across Sternglass’s work and Einstein’s interpretation. “What is truly mind boggling about this is that Einstein simply looked at Sternglass’ data and then immediately realized that the observed neutron production must involve some sort of many-body collective effects with electrons,” Larsen writes.
The Widom-Larsen papers harkened what can only be described as a minor renaissance in research into low-energy nuclear reactions (the term “cold fusion” having been dropped). In March of 2012, the Europe- an Organization for Nuclear Research (CERN), which runs the world’s most powerful particle collider, held its first colloquium related to the Pons-Fleischmann data since 1989. In November of 2012, the American Nuclear Society held a breakout session about low-energy nuclear reactions at their winter meeting in San Diego. And NASA’s Langley Research Center in Hampton, Va., has devised a series of experiments to test the Widom-Larsen theory.
Researchers are making clear that there is a growing body of experimental data that is consistent with the theory. Francesco Celani, researcher at the Italian Institute of Nuclear Physics, described to his CERN audience 20 experiments after Pons and Fleischmann that have also yielded inexplicable quantities of heat—though they were only sporadically repeatable. Yogendra Srivastava, professor of physics at the University of Perugia in Italy, explained at the same colloquium that hundreds of papers have been published about thin wires that, when overloaded with electric current, explode—and, according to some experiments, produce neutrons. He described how any potential technology based on low-energy neutron production would be the first exploitation by mankind of the weak force, one of the four fundamental forces of nature. As Joseph Zawodny, a senior research scientist at NASA Langley, put it, “I can’t imagine that there’s a whole force of nature out there, one of just a few, that is boring, disinteresting, and not of any use.”
At the same November American Nuclear Society meeting, Tadahiko Iwamura, from Mitsubishi Heavy Industries in Japan, described Mitsubishi’s experiments on neutron-induced transmutation. Iwamura said his lab had watched while the radioactive element cesium was transformed into a less-harmful heavier element, praseodymium, when deuterium had been forced to flow past it. Cesium is commonly found in nuclear waste. During the question and answer period, Iwamura surprised the audience with the admission that other scientists at Toyota had independently confirmed Mitsubishi’s transmutation data.
But the research faces a strong headwind of public and scientific skepticism. This is partly due to the continued activity of a much larger group of present- day cold fusioneers, who have failed to advance any tenable theory for tabletop nuclear fusion. “The distinction between the real science and the pseudoscience is not widely known yet,” says Steven Krivit, editor of New Energy Times, a newsletter devoted to the underground scientific movement kicked off by the Pons-Fleischmann experiments. Even NASA has taken its share of flak. In 2011, the watchdog website NASA Watch headlined a story with the title “Why is NASA Langley Wasting Time on Cold Fusion Research?”—a title which ignores the distinction between (strong force) fusion and (weak force) low-energy nuclear reactions.
The field is also plagued by the variability of experimental data, says NASA Langley chief scientist Dennis Bushnell. Sternglass’ inability to reproduce his Cornell data at Westinghouse was a first glimpse of this. Bushnell points out that according to the Widom-Larsen theory, inciting a proton to capture an electron requires extremely strong local electric fields, up to 100 billion volts per meter. “And there are several ways to get that,” Bushnell says. “One way is to up the voltage. The other way is to reduce the meters.” If transmutation does indeed depend on nanoscale features like dust grains, cracks, or impurities—features with “reduced meters”—then experimentalists must solve the difficult experimental challenge of controlling their materials at these scales.
Zawodny, while making clear that transmutation only holds a provisional promise, says that the applications to energy generation cannot be ignored. “Low-energy nuclear reactions still can’t boil a cup of tea,” he says. “But if this played out in the most optimal way, and this replaced all forms of energy generation, you’re talking about $6 trillion or more per year of market,” he says. “If this is real, the impact is so huge and the applications to our current problems and the ability to solve them quickly are so obvious that we cannot not do this.”
The researcher who agrees with Zawodny, and is intent on pursuing this controversial but potentially important line of research, will appreciate Einstein’s parting advice to Sternglass. In March 1954, thirteen months before Einstein’s death, Sternglass sent his mentor a copy of his latest publication on secondary electron emission as well as a 75th birthday card. In what would be his last letter to Sternglass, Einstein sent a printed thank you note. On the back of the card was a handwritten response consisting of just two words.
“Be stubborn,” Einstein said.
Mark Anderson is a science and technology journalist who has written for Discover, Technology Review, Scientific American, Science, Wired, IEEE Spectrum, New Scientist, and Rolling Stone.
Albert Einstein’s letters (written in German) to Ernest Sternglass were translated into English for this article by Hans-Jochen Trost. For more information on the Widom-Larsen theory and low-energy nuclear reactions, see the newsletter New Energy Times.
Thanks to Ephraim Fischbach for his expertise on this article’s technical aspects.
This article first appeared online in our “Waste” issue in November, 2013.