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The Disappearance of Ettore Majorana & The Key to Quantum Computing

“Ettore was too intelligent. If he has decided to disappear, no one will be able to find him.” 

-Enrico Fermi

Ettore Majorana was born in 1906 to a wealthy family in eastern Sicily, where his father, an engineer by trade, served as the Director of the Catania telephone company. Ettore was shown to be gifted in mathematics from a young age, being able to multiply three-digit numbers or extract cube roots all in his head. At the same time he was a shy child, often hiding under a table when asked to show his abilities, and would not emerge until he had shouted out the answer from underneath. 

In 1921 the Majorana family moved to Rome, where Ettore had already been sent to attend boarding school. Ettore completed boarding school in 1923, earning a diploma in classical studies and immediately entering an engineering preparatory program, which he graduated from in 1925. He then began a three-year engineering school, although he never graduated: Emilio Segrè, a classmate and friend of Ettore’s, had recently dropped out of engineering school in order to study theoretical physics at the University of Rome, and he convinced Ettore to follow the same path. They would both go on to study under a then 27 year-old Enrico Fermi.

After Ettore’s admittance to the university, he met with Fermi briefly and was shown some of Fermi’s work on his statistical model of the atom. After observing some of the figures Fermi had generated with the help of a mechanical calculator, Ettore left and returned the following day with his own set of figures he had calculated, and seeing that they matched Fermi’s exactly, announced Fermi to be correct. Within a week he had begun his thesis work with Fermi which would be completed one year later in 1929, and receive a grade of 110/110, with distinction. Ettore would continue publishing papers for the next few years, and 1932 he received his teaching diploma from the university, with the examination board reporting he possessed a “complete mastery of theoretical physics.”

Although Ettore was a proven genius in his field, he published very few papers when compared with his peers, and viewed his own work as boring. Once he had solved a problem or developed a theory, he no longer thought of it as interesting and showed no desire to publish his findings. One example was related to the discovery of a new particle: After reading that Irène Curie and Frédérick Joliot had identified a neutral particle entering matter and expelling a proton, Ettore believed the particle was yet unknown to science. At the time, the only known neutral particles were photons (i.e. light), but Ettore understood that a photon would not have enough mass to remove a proton, and the particle must be something new. Shortly afterward, this theory was confirmed in James Chadwick’s discovery of the neutron.

In 1933, Ettore received a grant of 12,000 Lire (~80,000 current USD) in order to travel to Leipzig, Germany and work with Werner Heisenburg. Ettore arrived in Leipzig in January of 1933, and his stay was punctuated by the appointment of Adolf Hitler as the chancellor of Nazi Germany, and the early days of dictatorship. After roughly six months in Leipzig, Ettore also traveled to Copenhagen for a three month visit with Niels Bohr. After this trip, however, Ettore ceased publishing papers entirely. It is not known why exactly he developed writer’s block, although it is often attributed to a serious case of gastritis developed in Germany which led to continued health issues. 

Ettore’s academic interests deviated from physics in the following years, and he began to study philosophy, including the works of Schopenhauer. (A philosophical pessimist and atheist) He also branched out into studies of economics and politics, seemingly leaving behind his interest in physics until 1937, when a selection of new physics chairs for Italian universities took place, and Fermi encouraged Ettore to apply for a position.

Although three candidates had already been selected for the three open positions, the examination committee requested that he supply a new paper for the consideration of his application. Based on his own previous research and theories, Ettore wrote and published his final paper, “Symmetrical theory of the electron and the positron,” which built on the theory at the time that every particle of matter had an antimatter counterpart. (This theory would eventually be verified by Ettore’s school friend Emilio Segrè) Ettore sought to show that the equations used to demonstrate the theory of antimatter also suggested that another type of particle could exist, one which was both matter and antimatter at the same time.

Unfortunately, Ettore was not selected for any of the physics chair positions, likely due to the son of an examination committee member occupying one of the chosen positions. Instead, the committee recommended him for a teaching position in Naples, which he accepted and began in January 1938, at a salary of 26,000 Lire. (~105,000 current USD) But after teaching for a few months, Ettore abruptly withdrew all of his savings from his bank account, and boarded an overnight boat to Palermo, Sicily on March 23. After arriving in Sicily, he sent a letter, followed by a telegram, to Antonio Carrelli, the Director of the Naples Physics Institute. A second letter was received by Carrelli shortly after the first. The first letter read as follows:

“March 25 1938

Dear Carrelli, I made a decision that has become unavoidable. There isn’t a bit of selfishness in it, but I realize what trouble my sudden disappearance will cause you and the students. For this as well, I beg your forgiveness, but especially for betraying the trust, the sincere friendship and the sympathy you gave me over the past months. I ask you to remind me to all those I learned to know and appreciate in your Institute, especially Sciuti: I will keep a fond memory of them all at least until 11 pm tonight, possibly later too. E. Majorana”

A telegram was then sent instructing Carrelli to disregard the first letter he will soon receive, followed later by the second letter:

“March 26, 1938

Dear Carrelli, I hope you got my telegram and my letter at the same time. The sea rejected me and I’ll be back tomorrow at the Hotel Bologna traveling perhaps with this letter. However, I have the intention of giving up teaching. Don’t think I’m like an Ibsen heroine, because the case is different. I’m at your disposal for further details. E. Majorana”

Carrelli immediately contacted Ettore’s family, and Ettore’s brother traveled to Naples where he determined that Ettore had boarded a return boat to Naples from Palermo on March 26, and shared a cabin with a professor from the University of Palermo. From this point on, any record of Ettore Majorana disappears, and nothing is known for certain about his whereabouts or fate.

Many theories have been put forward by those close to Majorana of his disappearance and possible death. The most obvious explanation is that Majorana, after attempting once in Palermo, took his own life on the boat back to Naples. This is supported by his notes sent to Carrelli, and proposed by several colleagues and friends of Majorana in Rome, including Emilio Segrè. Majorana’s family disputes these claims, and insists that he was too devout of a Catholic to commit suicide and instead retreated into a monastery, citing the fact that Majorana had withdrawn his savings before departing. This is supported by Majorana’s priest in Naples during this time, Monsignor Riccieri, who said that although he could not reveal details due to the sanctity of the confessional, Majorana had been experiencing “mystical crises.” Finally, several theories exist around Majorana’s advanced knowledge of quantum physics and the development of nuclear weaponry. Some believe that due to the volatile state of Nazi and Fascist politics in Europe at the time, Majorana may have been murdered for his knowledge which could have led to atomic weapons, possibly by Nazi agents seeking to tie up loose ends related to Heisenberg’s work. Others argue that knowing the potential for nuclear weapons and the power of the knowledge that he held, he decided to disappear, and fled to South America.

The South America theory seems to be the most well supported, with a report after his disappearance that Majorana had checked into a hotel in Buenos Aires. Detectives were dispatched to investigate, but they could not find any conclusive evidence that Majorana had stayed at the hotel. Unsubstantiated reports of sightings in Argentina or Venezuela came and went in the ensuing years, and eventually the case went cold. However, in 2011, the Rome Attorney’s Office announced a new investigation into Majorana’s disappearance, based on a statement made by a witness who had allegedly met with Majorana in Buenos Aires after the end of WWII. A photograph which allegedly showed Majorana was also analyzed by the Italian police’s RIS (Department of Scientific Investigations), who concluded the photo was of Majorana. Finally, in 2015 the Rome Attorney’s Office issued a statement that based on new evidence, Majorana had been living in Valencia, Venezuela between 1955 and 1959, and declared the investigation into his disappearance officially closed. This conclusion is still disputed to this day, with many not believing there was enough evidence to verify the theory.

In 2024, we may not have answers as to what really happened to Ettore Majorana, but we do know that his work has continued to be relevant past the nuclear era and into the era of quantum computing. Much like the nuclear arms race of the 1930s and 40s, a different type of arms race is currently taking place between tech corporations and physics researchers: one to discover the elusive Majarona particle described in his 1937 paper. 

The problem with the majority of quantum computing systems is their use of an atom for the computational quantum bit (qubit). Atoms, being made up of subatomic particles, are inherently noisy, and when outside environmental noise is added on, this creates a very unstable system. Due to this, current quantum computers need to be refrigerated to extremely low temperatures to function without errors. 

In 1997, the physicist Alexei Kitaev theorised a solution to this issue by taking advantage of an interaction between electrons and the empty space between them: Under certain conditions, a group of electrons and the “holes” around them can sync up and behave like a single particle. Shuffling the fragments of these quasi-particles around changes the probability of their final state, and because the outcome depends on how the fragments were shuffled, the particles have a sort of “memory." 

Kitaev realised that this behavior could apply to quantum computing, substituting an electron quasi-particle for the atom in a qubit. The key to carrying out computations with this system relies on linking an electron and a hole so perfectly that the electron effectively splits, producing two half-electron/half-holes. These particles would exist with zero charge and zero energy, the same as the particles which Majorana had theorised in his final paper a year before his disappearance. Since the electron is split between matter and antimatter, it does not technically exist in one place, making it unaffected by environmental noise. And because of the “memory” these electron quasi-particles have, they would also generate far fewer errors than atom-based qubits, requiring fewer qubits to process the same amount of data.

For the past 20 years, researchers at Microsoft, Google, and the University of California Santa Barbara, among others, have been attempting to create the Majorana particle. Many have claimed to be successful, but under further scrutiny were shown to have missed the mark. But work on the Majorana particle continues, with many physicists seeing it as quantum computing’s only hope of turning delicate, unstable devices into practical, powerful computers.

The story of Ettore Majorana’s life and legacy will always be occupied by countless theories. Whether pertaining to his academic work, or his disappearance, his life creates more questions than answers. Research into Majorana continues to this day, with a folder found in 2020 in the archive of his colleague and friend Emilio Segrè, with instructions that it is not to be opened until 2057. While we may never know what truly happened after Ettore’s disappearance, we do know that he was among the greatest physics minds of his generation, and his work will continue to inspire scientific advances into the future.

“Because you see, in the world there are various categories of scientists: people of a secondary or tertiary standing, who do their best but never go very far. There are also those of high standing, who come to discoveries of great importance, fundamental for the development of science. But then there are the geniuses, like Galileo and Newton. Well, Ettore was one of these. Majorana had what no one else in the world had ..."

-Enrico Fermi

Citations:

https://iopscience.iop.org/article/10.1088/1742-6596/173/1/012019/pdf

https://www.science.org/content/article/ghostly-quasiparticle-rooted-century-old-mystery-unlock-quantum-computings-potential

https://cerncourier.com/a/ettore-majorana-genius-and-mystery/

https://www.historicalstatistics.org/Currencyconverter.html

Physics Who’s Who Cheat Sheet & Further Reading:

Enrico Fermi: Italian and naturalized American physicist, member of the Manhattan project, and originator of the Fermi Paradox. (If there are aliens, “Where is everybody?”) Awarded Nobel Prize in Physics in 1938.

Emilio Segrè: Italian and naturalized American physicist, discovered the antiproton along with two new elements. Awarded the Nobel Prize in Physics in 1959.

Irène Curie and Frédérick Joliot: French physical chemists, and the daughter and son-in-law of Marie Curie. Awarded the Nobel Prize in Chemistry in 1935 for the discovery of new artificially prepared radioactive isotopes.

James Chadwick: English physicist, received the Nobel Prize in Physics in 1935 for the discovery of the neutron.

Werner Heisenburg: German physicist, considered the founder of quantum mechanics, and was one of the main scientists behind Germany’s nuclear weapons program during WWII. Awarded the Nobel Prize in Physics in 1932.

Niels Bohr: Danish physicist, made early contributions to ideas of atomic structure and quantum theory, and developed the Bohr model of the atom. (The one you probably learned about in high school) Awarded the Nobel Prize in Physics in 1922.

Majorana’s Final Published Paper:

http://www.physics.umanitoba.ca/u/tapash/Majorana_1937.pdf

A Brilliant Darkness, by João Magueijo:

https://archive.org/details/brilliantdarknes0000magu

What is Real, by Giorgio Agamben:

https://archive.org/details/giorgio-agamben-what-is-real

The Moro Affair and The Mystery of Majorana, by Leonardo Sciascia

https://archive.org/details/moroaffairandmys0000scia