Lemaitre: The Priest and the Big Bang

Lemaitre: The Priest and the Big Bang

“Science is beautiful. It deserves to be loved for itself, as it is a reflection of God’s creative thought.” - Lemaitre’s address on returning to Louvain University after receiving the Francqui Prize

Georges Lemaitre is regarded as one of the greatest cosmologist of all time, largely for his reputation as the “Father of the Big Bang.” Yet until recently he was fairly unknown. There are various reasons for this, not least the fact that he was a Catholic priest, and many in the scientific community took exception to having the way forward in cosmology shown to them by such a person! For Lemaitre science and religion were neither in conflict nor either one reliant on the other, as illustrated in this passage from one of his early reflections on such matters:

“His (the religious scientist’s) faith gives a supernatural dimension to his greatest as well as his smallest activities! He remains a child of God when he put his eye to the microscope, and as well, in his morning prayer, where the entirety of his activity is to place himself under the protection of his Father in Heaven. When he thinks of the truths of faith, he knows that his knowledge of microbes, atoms or suns will neither be a benefit nor a hinderance to approach the inaccessible light, and, as for any man, he would need to try to have the heart of a little child to enter the kingdom of heaven. Thus, faith and reason, without undue mixture or imaginary conflict, are unified in the unity of human activity.”

The light Lemaitre describes here is typical of the experiences of Christian mystics, which the Catholic priest certainly seems to have been. As the young Lemaitre closed his eyes and began his daily spiritual exercises of prayer and mediation some day in the 1920s, his mind may have wandered as it often did to science, and in particular to the nature of the physical universe. Yet what flashed before the eyes of Lemaitre as he envisioned the cosmos would have been something entirely different to what any human had previously seen. Almost all scientists at the time favoured an eternal universe with no beginning. This had been the view of Newton, and was supported by Einstein at the initial publication of relativity theory in 1916. Instead Lemaitre would have visualised a universe in which space itself was expanding, a universe with no end in which galaxies were carried into a future in which the cosmos became ever more empty, as galaxies glowed with a reddened hue not because of the Doppler effect but because light waves themselves were stretched out by the expansion of space, a universe that lacked any meaningful centre because no observer was in any special position, a universe which flowed from a mystery in which time itself had a beginning.

The coincidence of Lemaitre’s model with the Christian view of a universe stemming from a moment of creation at the very beginning of everything has lead to him being hailed in Christian circles as proving the truth of the Christian metaphysical position. The creation of the universe out of nothing at the “beginning of time” set Christianity apart from most other religions which tended to see the universe as existing forever while moving through repeating cycles, and so when Lemaitre proposed the same idea from a scientific perspective he was hailed by many as having proven Christian doctrine.

But Lemaitre, in public at least, would have none of this was, which eventually lead to the usually amiable priest travelling to Rome to berate the Vatican for too enthusiastically linking Christian cosmology to big bang physics. For Lemaitre, you see, the new cosmos that he envisioned in these reflective moments was merely a distraction from the prayer states he sought, and the truths of physics of secondary importance to the higher and more significant truths of devotional communion with the transcendent God. Although there is evidence that he did privately think it likely that the moment of creation implied by the big bang was divine, he did not think that linking science and religion in this way was helpful for Christianity, and became guarded against it.

Lemaitre’s contributions to physics were up there with the other great scientists of the golden age. Not only did he seed the modern big bang model but also discovered Hubble’s law before Hubble himself did (it was eventually renamed the Hubble-Lemaitre law in 2018), front ran the Friedman-Robertson-Walker metric which connected general relativity to cosmology, and pre-cursed Einstein’s calculations of the cosmological constant. Yet for several decades he was rather forgotten, until a resurgence of interest and scholarship of his work ensued from around the turn of the millennium.

Above: The Belgian priest and Louvain cosmology professor in the 1930s.

The reason he is not better known is down to a number of factors. One of the great originals of academic history who fitted the stereotype of the eccentric genius as well as any one I have covered, Lemaitre was motivated very little by conventional success and acceptance. He published his work in relatively obscure French language science journals, and if not for his discovery by Arthur Eddington who demanded attention for Lemaitre’s model and saw to it that his work was reprinted in more prominent places, his model of the expanding universe may have failed to garner any major attention at all. Lemaitre also seemed to lose interest in the cosmology of the first moment after the end of the 1930s and developed more of an interest in classical mechanics, in computer science, in stewardship of students in his ecclesiastical role, in developing new systems of numbers derived from musical notation, and even in studying the work of the French playwright Moliere.

There is also no doubt that a portion of the scientific community were highly aversive to having their ideas challenged by a priest, of all people. Lemaitre’s theory of the universe expanding from a point was rejected out-right by many scientists due to the religious connotations. Typical of his sense of humour, Lemaitre appeared to enjoy teasing the materialist community over this, turning up to scientific conferences in his priest’s attire!

He developed a life long interest in the Thirteenth Century Belgian mystic John van Ruysbroeck, who taught a path of personal meditation to reach an intimate union with God.

Lemaitre’s interest in science and in religion were strong from a young age. In the same month, at the age of nine, he made up his mind to become both a scientist and priest. At the age of seventeen he enrolled at the University of Louvain to study engineering. But his studies were interrupted by the war, as he was conscripted to the Belgian army in 1914. It is during the war that the stories of Lemaitre begin, which scholars have reconstructed from letters and conversations with those who knew him, and became part of his folk law.

Something or a loner and an ascetic, but also highly jovial and conversational when with company, Lemaitre studied Poincare on the front line, and liked to educate other soldiers on scientific topics during quiet periods. Stationed as an artillery operator he corrected errors about trajectory calculations in the ballistics manuals, which angered his instructor and appeared to be what lead to him never progressing in army rank. He also formed life long friendships on the front line. While in the trenches between two battles he also made copious notes and planned a new cosmology based around radiation.

Lemaitre changed course after the war, studying a mathematics and physics masters degree under the famous mathematician Charles De la Vallée Poussin. After this he completed a philosophy course in the work of Aristotle and Aquinas. From 1920-1923 he undertook three years of ecclesiastical studies at the  Seminary of Malines to qualify for the Catholic priesthood. His grades in philosophy were merely average in comparison to others on the course and contrasted with the consistently outstanding results he had achieved in physics and mathematics. Lemaitre’s journals reveal far more focus on personal spiritual development during this time than concern for the finer points of theology. He developed a life long interest in the Thirteenth Century Belgian mystic John van Ruysbroeck, who taught a path of personal meditation to reach an intimate union with God.

On graduating from seminary Lemaitre took vows of chastity, poverty, and obedience, and another called the votum immolationis – a vow of complete submission of the life to Christ. He took the four vows extremely seriously, committing to an hour of prayer a day for life, and attending every silent retreat of his priestly brotherhood between 1934 and 1960. His notebooks reveal that the retreats were not just about his spiritual life but also involved deep reflection on his scientific teaching, research ideas, and planned calculations.

Lemaitre arrived in Cambridge for the start of the 1923 academic year to study physics under Eddington and Rutherford, and mathematics under Hobson. This was the beginning of a life long friendship and mutual respect between Eddington and Lemaitre. Eddington describing Lemaitre as “a very brilliant student” with “great mathematical ability”. It may have been Eddington who made Lemaitre aware of the dangers of basing religion on science. As we have seen elsewhere Eddington, also a Christian, saw good reason not to overemphasise any grounding that religion might find in the science of some particular age. There is evidence that Lemaitre shifted his view away from one of a loose concordance of the story of Genesis with science (Genesis evidences roughly the same order of evolution of plants and animals, for example) after spending time working with Eddington at Cambridge.

In 1924 Lemaitre arrived in USA at the Harvard Observatory and spent three years gaining a PhD from MIT. Biographers have marvelled at how all of the pieces needed for his model came to him so quickly, through chance meetings with other scholars or through public lectures that were located close enough for him to be able to attend.  The 1920s world was much more disconnected than today’s, and researchers would often miss work that could have added core information to their own studies as they were simply unaware of it. During a very short period he acquired, more through chance than anything: the expanding universe concept (from de Sitter), observational values of stellar distances (through Hubble’s lecture), relative velocities of nebulae (from Slipher), the extragalactic nature of nebulae and equations of non-homogeneous model with spherical symmetry (from his MIT PhD), and the idea of extra-terrestrial cosmic rays (from Milikan).

Lemaitre returned to Louvain to take up a faculty position in 1925, and 1927 saw the publication of his seminal paper on the expanding universe in the French language journal Annales of the Scientific Society of Brussels. The paper was Lemaitre’s master piece, offering a reinterpretation of general relativity in which the universe originated from a finite point in time. The concept of a universe that was expanding was not new, having already been explored by de Sitter, in a theoretical universe which was completely flat and devoid of ordinary matter. Lemaitre’s contribution was to make the mathematics work for our own universe. In doing this he gave the world the seed from which the contemporary understanding of the big bang grew.

In another chance meeting in the United States, Lemaitre met Einstein and briefly explained his idea. “Your calculations are correct but your grasp of physics is abominable,” was Einstein’s characteristically bluff response.  By 1929 however, Einstein’s own interpretation of general relativity was to be brought into question by Hubble’s observation of other galaxies, and Einstein was ultimately forced to backtrack.

Due to the choice of publication, Lemaitre’s paper went all but unnoticed by the scientific community, and but for Lemaitre’s friendship with Eddington it may have stayed that way. The British Astronomical Society met in 1929 to consider the conflict between Hubble’s new data and the current interpretation of general relativity. Following the meeting Lemaitre sent a copy of his paper to Eddington, and the English astronomer immediately recognised its originality and significance. At Eddington’s request, it was translated into English and published in Monthly Notices of the Royal Astronomical Society in 1931. In May of that year Lemaitre had introduced the idea to the scientific community through an informal letter to the journal Nature, which he signed as a member of the public, not as a professor. The text of the letter:

The Beginning of the World from the Point of View of Quantum Theory.

SIR ARTHUR EDDINGTON states that, philosophically, the notion of a beginning of the present order of Nature is repugnant to him. I would rather be inclined to think that the present state of quantum theory suggests a beginning of the world very different from the present order of Nature. Thermodynamical principles from the point of view of quantum theory may be stated as follows : (1) Energy of constant total amount is distributed in discrete quanta. (2) The number of distinct quanta is ever increasing. If we go back in the course of time we must find fewer and fewer quanta, until we find all the energy of the universe packed in a few or even in a unique quantum. Now, in atomic processes, the notions of space and time are no more than statistical notions ; they fade out when applied to individual phenomena involving but a small number of quanta. If the world has begun with a single quantum, the notions of space and time would altogether fail to have any meaning at the beginning; they would only begin to have a sensible meaning when the original quantum had been divided into a sufficient number of quanta. If this suggestion is correct, the beginning of the world happened a little before the beginning of space and time. I think that such a beginning of the world is far enough from the present order of Nature to be not at all repugnant. It may be difficult to follow up the idea in detail as we are not yet able to count the quantum packets in every case. For example, it may be that an atomic nucleus must be counted as a unique quantum, the atomic number acting as a kind of quantum number. If the future development of quantum theory happens to turn in that direction, we could conceive the beginning of the universe in the form of a unique atom, the atomic weight of which is the total mass of the universe. This highly unstable atom would divide in smaller and smaller atoms by a kind of super-radioactive process. Some remnant of this process might, according to Sir James Jeans's idea, foster the heat of the stars until our low atomic number atoms allowed life to be possible. Clearly the initial quantum could not conceal in itself the whole course of evolution ; but, according to the principle of indeterminacy, that is not necessary. Our world is now understood to be a world where something really happens ; the whole story of the world need not have been written down in the first quantum like a song on the disc of a phonograph. The whole matter of the world must have been present at the beginning, but the story it has to tell may be written step by step. G. LEMAITRE. 40 rue de Namur, Louvain.

The letter contains two religious ideas. Firstly, it describes creation ex nihilo, paraphrasing the words of the Christian Saint, Augustine of Hippo. Secondly it creates room for indeterminacy, and by implication for free will. Lemaitre uses the inherent randomness of quantum fluctuations to show that a universe flowing from a fixed point need not be predetermined, because the future of the universe could not be predicted from the initial conditions.

In 1932 Eddington pointed the attending journalists attention to Lemaitre at the general assembly of the International Astronomical Union. This resulted in immediate press attention and his views on both cosmology and religion from then on were followed quite closely by the large American newspapers. In marked contrast to his earlier attitude Albert Einstein, after hearing a talk by Lemaitre in California in 1933, stood up and applauded saying "This is the most beautiful and satisfactory explanation of creation to which I have ever listened." From 1935 Lemaitre began to receive recognition in physics for his contributions. He was awarded the Mendel Medal in January 1934, and in March of that year received the Francqui prize from King Leopold III of Belgium. On returning to Louvain a crowd of cheering students gathered beneath his balcony. At an address at Louvain University following his return he made the following remarks:  “Science is beautiful. It deserves to be loved for itself, as it is a reflection of God’s creative thought.” In May he received an honorary PhD from McGill University. In 1936 he was awarded the Prix Jules Janssen by the Astronomical Society of France.

Most scientists accepted that the universe might be expanding, it was the universe having a beginning that they took exception to. The theory was not to gain complete acceptance until the 1960s when technicians at Bell Labs in New Jersey accidently discovered the cosmic background radiation in 1965. Lemaitre was informed of the discovery in 1966, the last year of his life.

Lemaitre resolutely refused to use science as evidence for Christianity when he knew that better evidence existed elsewhere.

Lemaitre’s effect on science was extremely large. He challenged, and ultimately succeeded in overturning, the eternal universe model which dated back to the Greeks. His work was also absorbed by theologians into the growing tradition of Christian rationalism which sought to establish rational reasons for the Christian faith grounded in modern research. In the eyes of a great many thinkers the Belgian priest’s work and later big bang models ultimately aligned science with the Judaeo-Christian model of the universe which described creation “ex nihilo” – creation of a natural world by a creator from a prior form which had nothing in common with nature as it is known to science, and could therefore be termed a supernatural source.

But the Catholic cosmologist, at least in public and on the record, would have none of this and never spoke publicly of his universe originating from a moment of “divine creation”. Lemaitre resolutely refused to use science as evidence for Christianity when he knew that better evidence existed elsewhere. In a revealing comment, he disagreed with Dirac that cosmology was the branch of inquiry closest to religion, instead arguing that psychology was: for Lemaitre belief personal experience was a surer route to knowledge of God than science.

Lemaitre had a rich interior spiritual life, spending an hour a day in prayer and contemplation, as well as consistently attending the annual silent retreat. For him the Bible was not intended to be read as a science manual, instead it was an inner guide to spirituality. When Genesis 1 tells us that God rested on the seventh day for example, this should not be taken to mean the world actually took six days to create, but that it is good for our spiritual growth to rest on Sundays. Focussing too heavily on the scientific grounding of religion might distract us from the more important work of connecting to God personally.

So these were some of the reasons why Lemaitre preferred to de-emphasise any connection between his cosmology and the moment of creation described in Genesis. His effect on religion was actually to reduce the Church’s reliance on science and encourage a distancing of the two. Lemaitre was concerned with the way the church had side-lined conscious religious experience in favour of rational arguments, a tendency that can be traced to Aquinas and Scholasticism and redoubled with Descartes and Newton, who proclaimed science as the servant of religion and sought a thoroughly rational basis for Christianity. Lemaitre can be credited with moving the Church away from the slightly obsessional focus on basing Christianity in science which it had developed – even while simultaneously supplying it, in the eyes of many – with its best argument from science. Following Lemaitre, Rome appeared to show a greater appreciation that scientific discoveries should not be mistaken for knowledge of truly ultimate things, no matter how closely they may appear to provide proof of a Christian universe. Both Lemaitre and the Pope appeared to conclude that Christianity, having apparently got the upper hand from atheism in terms of the implications of science, could now afford to begin to reemphasize the older aspects of the path which revolved around scriptural revelation and mystical experience.

Privately Lemaitre did appear to favour the view that the beginning of the universe was the moment of creation described in Genesis, remarking “Of course, the primeval atom is created by God” to Msgr. Massaux at start of the Second Vatican Council, but he preferred to keep science and religion separated in public statements. He may have known that he did not need to make the connection with the Judaeo-Christian creator, that others would do it for him, as many certainly did, and that he was better off focussing on getting the theory taken as seriously as possible in the scientific community.

In November 1951 Pope Pius XII delivered his Un’Ora discourse to the Pontifical Academy of Sciences. Pius had grown up with a strong interest in science, occasionally keeping company with the astronomer Giuseppe Lais in his youth through family acquaintance, and had studied astronomy to a university level as part of his seminary. Pius continued to regularly discuss astronomy with the director of the Vatican observatory. His remarks in the Un’Ora discourse are worth repeating as they illustrate the relevance of Lemaitre’s model to the Christian religion:

“With the same clear and critical gaze with which he (the scientist) examines and judges facts, he also catches sight of and recognises the work of the omnipotent Creator, whose power aroused by the mighty ‘fiat’ pronounced billions of years ago by the Creative Spirit, unfolded itself in the universe and, with a gesture of generous love, called into existence matter, fraught with energy. Indeed, it seems that the science of today by going back in one leap millions of centuries, has succeeded in being a witness to that primordial Fiat Lux, when out of nothing, there burst forth along with matter a sea of light and radiation, while the particles of chemical elements split and reunited in millions of galaxies.”

Above: Pope Pius XII, a life-long science enthusiast, looks through a telescope at the Vatican observatory.

The Pope’s address did not mention Lemaitre’s name directly, though he did mention some terms from his theory such as the “primeval atom.” Instead he relied heavily on the work of Edmund Whitaker, a world class mathematician who had converted to Catholicism in 1930. Whitaker had written a book called Space and Spirit: Theories of the Universe and the Argument for the Existence of God. This book put forward the thesis that the expanding universe implied a beginning and therefore a creation.

Lemaitre is reported by those in attendance to have expressed dissatisfaction with the Pope’s message to everyone he spoke to. In September 1952 the Pope planned a similar address to the International Astronomical Union at a meeting in Rome. By now Lemaitre had seen and heard enough and travelled to Rome to intervene directly, speaking with members of the papal Secretariat of State, including Angelo Dell’Acqua who helped draft the papal addresses. It is not known exactly what was said but a credible and conservative assumption is that Lemaitre expressed that he was uncomfortable with Christianity coming to rest too heavily on a scientific theory that was not yet fully accepted by the cosmology community.

The Pope however continued with a very similar message in the 1952 address though without mentioning Lemaitre’s name or work:

“In its intrepid audacity, the human mind does not qualm in front of the most formidable cataclysms of a nova or supernova, it measures the incredible speeds of gases released and seeks to discover its causes. It darts towards the traces of galaxies fleeing in space, thinking back over the course that they have followed over billion of years in the past, and in this regard become the spectator of the cosmic processes that occurred in the early morning of the creation.”

“it is impossible that even the most gifted researcher could succeed in knowing, much less resolve, all of the enigmas enclosed in the physical universe. They postulate and point to the existence of an infinitely superior Spirit, of the divine Spirit that creates, conserves, governs, and consequently scrutinizes with a supreme intuition, everything that exists, today just as at the break of creation’s first day.”

Sentiments like these are perhaps little known outside of Catholic circles, where media forms public opinion, and the myth of a conflict between science and religion continues to be perpetuated.

Despite the similar content of the two speeches, the incident has been remembered as something of a turning point, after which Rome sought to de-emphasise the connection between Christianity and science. Subsequent Popes were more likely to opine that Christianity should not be simplified to concordance with science. While acknowledging that science was not atheistic and had revealed nothing that contradicted Christian assumptions, later Popes were more likely to emphasise the self-sufficiency of Christianity independent of science. John Paul II’s comments provide examples: “Christianity possesses the source of its justification within itself and does not expect science to constitute its primary apologetic”, “Scientists… can come to appreciate for themselves that these discoveries cannot be a substitute for knowledge of the truly ultimate.” There was a movement back to the traditional triadic approach to knowledge in Catholicism, in which revelation, scripture, and science were emphasised more equally. The Belgian cosmologist’s relationship with Pius XII remained friendly and respectful despite their differences.

In a talk given at the Catholic University of Paris in 1950 Lemaitre expressed a different connection between science and religion. Science, instead of revealing the total picture of  the universe, might be employed to help in our mastery over the world, and our subsequent ability to care for it, and each other:

“I hope to have shown you that the universe is not out of reach for humans. This is Eden, this garden that has been put at the disposal of humans in order for them to cultivate it, to look after it. The universe is not too big for human beings, it does not exceed the possibilities of science, nor the capacity of the human mind.”

The spiritual role of science was to render power over aspects of the universe which could be used to do good in the world.

His students mostly forgave his poor teaching skills for the privilege of watching one of the great masters of modern cosmology in full flow.

Lemaitre was a friendly and jovial character, with many friends at the University of Louvain and in the town itself, as well as in the international science community. He was tremendously forgetful of meetings and appointments as attested in various letters between colleagues. By all accounts he was a rather chaotic teacher, but he went down well with students, as Ladous observed “he was loved by his students and did not qualm participating in their meetings in the middle of tobacco smoke and beer steam that flowed abundantly”. His classes mixed mathematical brilliance with extreme disorganisation and moments of comedy.

Lemaitre’s style in the classroom has been likened to a concert pianist casually improvising in a bar. Generally lacking preparation for classes he would start in some random place and hammer out a series of never to be repeated equations which worked to illustrate some point, while his students marvelled at the mathematical acrobatics he could perform on a whim. Occasionally he would storm out of the class in feigned frustration when such a mathematical exploration did not end up where he had imagined, leaving the class in humorous uproar.

Very few students were able to follow much of his teaching. He generally misjudged the level of difficulty and would wander far from the original point he had set out to establish before finding his way back. His students mostly forgave his poor teaching skills for the privilege of watching one of the great masters of modern cosmology in full flow. He regularly featured in the annual university variety performance with one student or another performing a comedy sketch of his classes.

Lemaitre is said to have more than once turned up to the student examination having forgotten to prepare exam papers. On one occasion he failed to turn up to oversee the exam at all, and realising his mistake a few hours later entered the student area to inform them they would all be awarded the same (high) mark. He sometimes garnered trouble with the university authorities when some or the more earnest students would complain, but his reputation in Belgium generally put him beyond reproach. This was not to say that Lemaitre took liberties: in fact his journals reveal frustration that he failed to develop a more organised teaching style despite genuine resolutions to improve, and that he never found the time to finish writing a planned textbook.

His one success in the area of pedagogy was the influence of another of his pet projects: the development of alternative arithmetic systems. Lemaitre became convinced that the Western number system could be improved in a way that made calculation easier and more intuitive. Beginning after World War Two he invented several new systems of numbers based on musical notation, Chinese characters, and other systems in which the symbol bore resemblance to the number it represented (rather like how the Roman numeral for three is composed of three lines.) By the 1960s his systems of arithmetic were all Lemaitre wanted to talk about, and he sought volunteers, including his nieces and nephews, to test ability to perform basic arithmetic using his new systems. Eventually classroom experiments were run to test one of the systems, organised by Georges Papy, an expert in the teaching of mathematics. The system failed to find widespread adoption in schools, but was used in the work of Papy going forwards.

Lemaitre’s fascination with changing basic arithmetic methods was regarded with a mix of amusement and incredulity from his colleagues and students. But once again, he was vindicated. One of the systems, a hybrid of binary and decimal representation using ones and zeros, was to become the system that was used to encode data in computer memory. Other aspects of his work precursed modern approaches to child cognition in educational psychology, though his thesis that the form of numerals should express what they represent has not been born out by more recent research.

Lemaitre never sought widespread acceptance. He was happy for his work to be found by those who were interested, and never sought promotion of himself or his ideas. He preferred to move on to other areas of interest than to continue to push his primeval atom hypothesis. By the end of the 1930s his interest in Riemannian geometry, tensor calculus, and other mathematical aspects of general relativity had been precluded by his interest in classical mechanics.

Above: A Burroughs E101, in Lemaitre’s Laboratory of Numerical Research. Lemaitre repurposed this early office computer to calculate the behaviour of clusters of galaxies in the final phases of the universe.

After the 1930s he became absorbed in solving problems using computers, and can be regarded as a forerunner in the use of machines for calculation, regularly procuring some new machine from a bank or some other office and reprogramming it for his own purposes. His mother’s house, where Lemaitre lived after the war for over ten years until her death, became a home to his machines, which filled kitchen cupboards while the larger ones had dedicated rooms.

His lectures often ended with him asking for assistance from students to move a new computer up to the department. Computers were so large and cumbersome that sometimes a winch was necessary in order to get the parts upstairs. Programming the machines involved arranging rods, pins, or small blocks in slots to create circuits. Circuits would reflect low level mathematical processes which could be linked together, repeated, and amplified to perform complex equations. When performing long calculations some blocks would have to be moved manually by the operator, and the ingenuity with which this was done would enable the machines to perform above the manufacturer’s standards.

Around 1950 Lemaitre purchased a Moen Hopkins machine from a bank, where it had been used to calculate interest payments, and reconfigured it to calculate outputs of differential equations which described the shape of nebula clusters. In 1958 he procured a Burroughs E101. The E101 was not an advanced computer even for the time, it could hold only two hundred numbers in its memory. Lemaitre seemed to enjoy the challenge of programming and  expanded its memory to four hundred numbers. He had a special interest in finding ways to get machines to perform to a standard far above the manufacturers specifications. When employed for the departments purposes it had to be paused and the room left with the windows open for the machine to cool from time to time. Lemaitre and his colleague Barhtolome used it to solve equations about the behaviour of clusters of galaxies in the last expansion phase of his model of the universe, where it filled in data that they had been unable to calculate for years. The E101 would be placed with a group of Mercedes calculating machines to form his Laboratory of Numerical Research. In 1961 he obtained use of a Remington Rand machine, which was used to calculate various orbits of the three-body problem. In 1962 he bought an NCR-Elliott 802 computer capable of storing 1024 numbers of up to 33 digits, which he programmed in ALGOL. Lemaitre also developed his own programming language called Autocode which was a precursor of the much better known language Basic.

Beginning in the 1940s and continuing through to the 1960s Lemaitre also devoted considerable time outside of science altogether – to the study of linguistics. He was particularly fascinated by the work of the seventeenth century playwright and actor Jean-Baptiste Poquelin, better known as Molière. In the early 1950s he set aside his scientific interests and Molière became his primary area of study. Returning to mathematics by the mid-1950s, Lemaitre’s later work, produced between the ages of fifty five and sixty nine, is regarded as some of the most beautiful that he produced.

Conclusion. Lemaitre is credited with discovering what became known as the big bang: Yet another of the buttresses of modern science had been supplied not by materialists, but by a committed Christian believer. The claim, made largely by others and not by him, that his model discovered the moment of Biblical creation, remains a major theme of discussion in both academic theology and in spiritual writing aimed at the general public. The increased time frames his model brought into cosmology have fashioned a grander scope for theology as well as well as science, which now speculates on the nature of God’s unfolding through billions of years into the past and future. Initially accused (wrongly) by the scientific community of allowing theology to shape his science, he is sometimes criticised today in theology for portraying the support for Christianity that can be derived from science as less significant than it really is.