Would we have been able to understand the universe without Albert Einstein’s intuition? Inspired by a fascinating science fiction premise—an alien civilization capable of interstellar travel but completely ignorant of relativity—this article explores Einstein’s irreplaceable contribution to the history of science. The Theory of General Relativity did not emerge from a mere accumulation of experimental data, but from an astonishing intellectual audacity driven by what the physicist himself considered a “moral responsibility to the truth.” Without his courage to challenge classical notions and discover that space and time form a dynamic fabric, our modern understanding of the cosmos, the origin of the Big Bang, and even everyday technologies like GPS would be impossible today.

The Enigma of Erid: Science fiction that invites reflection

The novel  Project Hail Mary  presents a fascinating idea: a technologically advanced civilization capable of traveling between the stars and yet ignorant of the laws of relativity.

The novel tells the story of Ryland Grace, a scientist who wakes up alone on a spaceship with no memory of who he is or how he got there. He gradually regains his memory and discovers that he has been sent on a desperate mission to save Earth from an extraterrestrial microorganism that threatens to cause global extinction. His destination is the Tau Ceti star system . ^[1]

There, he encounters an extraordinary surprise: an alien spacecraft piloted by an intelligent being. Despite their profound biological and sensory differences, they manage to communicate and discover that their respective planets, Erid and Earth, are threatened by the same phenomenon. The novel recounts the scientific and human challenges they face as they attempt to solve it.

The author, Andy Weir, meticulously researched the various scientific topics featured in the novel, resulting in a work where science serves not merely as a backdrop, but as the driving force of the narrative. Weir introduces imaginary life forms that, while fictional, follow plausible biochemical rules; he convincingly describes the development of a common language among species with entirely different sensory systems; and he incorporates relativistic effects associated with high-speed travel. All of this is accompanied by countless details that reflect, with remarkable accuracy, the current state of our scientific knowledge.

But one of the novel’s most intriguing premises is another: the alien civilization possesses the technology to travel between stars, yet it is unaware of the laws of relativity. Albert Einstein never visited Erid, the alien’s home planet, and that civilization never developed the theory that describes gravity as the curvature of spacetime. This idea immediately leads to a fascinating question: would we have been able to understand gravity on a cosmic scale without Einstein’s insight? What state would science be in today if Einstein had never existed?

How Einstein arrived at General Relativity

Albert Einstein was a unique scientist. In 1905, while working examining applications at the Bern Patent Office, he published five articles that transformed physics and made that year his celebrated  Annus Mirabilis . In them, he tackled fundamental problems of classical mechanics, electromagnetism, and thermodynamics with unprecedented boldness.

His doctoral thesis,  Determination of Molecular Dimensions , earned this comment from his biographer Walter Isaacson: “His thesis would become one of his most cited and most practical works, with applications in fields as diverse as cement mixing, milk production or aerosol manufacturing” ^[2] .

In June 1905, he published  “On a Heuristic Viewpoint Concerning the Production and Transformation of Light ,” a work in which he explained the photoelectric effect using the hypothesis of light quanta. Decades later, this research would earn him the 1921 Nobel Prize in Physics.

Shortly afterwards appeared his study on Brownian motion,  On the motion of small particles suspended in a stationary liquid, required by the kinetic-molecular theory of heat , which provided one of the first solid proofs of the existence of atoms, still debated at that time.

On September 26, he published  On the Electrodynamics of Moving Bodies , in which he formulated the theory of Special Relativity. In it, he overturned the classical notions of absolute space and time and established the constancy of the speed of light.

That same year he completed the circle with a short article,  “Does the inertia of a body depend on its energy content?” , in which he derived the most famous equation in history: E=mc²

In just a few months, Einstein had laid the foundations of quantum mechanics, reinforced the physical reality of atoms, and revolutionized our understanding of space, time, mass, and energy.

But his mind was restless because, for him, physics was more of a moral responsibility to the truth. Special relativity stated that nothing can travel faster than light, but Isaac Newton’s law of gravitation implied instantaneous gravitational action at a distance. Einstein immediately perceived the contradiction: he needed a new theory of gravity compatible with the cosmic speed limit of light.

In 1907, he had what he described as “the happiest thought of my life.” He imagined a person falling freely from a roof: during the fall, they would not feel their own weight. From this intuition, he formulated the principle of equivalence, according to which the effects of gravity and acceleration are locally indistinguishable.

Through thought experiments he analyzed accelerated and rotating systems, arriving at a The revolutionary conclusion: these systems could only be accurately described by non-Euclidean geometry, that is, curved space. If acceleration required curved geometry, then gravity also had to be a manifestation of the geometry of spacetime. Gravity thus ceased to be an invisible force and became a property of the structure of the universe.

To express this idea mathematically, he had to delve into territories he barely knew: the geometry of Bernhard Riemann and tensor calculus. He relied on the crucial help of his friend, the mathematician Marcel Grossmann.

The following years were an exhausting intellectual struggle. Einstein progressed amidst brilliant insights, mathematical errors, and constant doubts. He moved to Berlin and worked almost obsessively until, in November 1915, he finally presented the equations of General Relativity.

Recalling that process, he wrote: “The years of searching in the darkness for a truth one feels but cannot express, the intense desire and the alternations between confidence and doubt until one achieves clarity and understanding, are known only to those who have personally experienced them” ^[3] . The result was a set of equations of enormous mathematical complexity that describe how matter and energy deform spacetime. Decades later, John Wheeler summarized them with unsurpassed elegance: “Matter tells spacetime how to curve; spacetime tells matter how to move” ^[4] .

Would General Relativity have emerged without Einstein?

The question of how science would have evolved if Einstein had not existed has been posed many times, and the answers vary considerably. It is important to remember, first of all, that at the beginning of the 20th century there was no urgent experimental pressure to replace Newton’s theory of gravity. The only significant problem was the anomaly in Mercury’s perihelion, which advanced about 43 arcseconds per century more than predicted by Newton’s equations. Furthermore, Henri Poincaré had expressed doubts about the possibility of gravity acting instantaneously at a distance. However, these issues were not at the forefront of physics research at the time.

In fact, even after General Relativity was formulated, the theory was met with a degree of indifference and skepticism. The Royal Swedish Academy of Sciences never awarded Einstein the Nobel Prize for relativity. When he finally received the prize in 1922, it was “for his services to theoretical physics, and especially for his discovery of the law of the photoelectric effect.” Even at the award ceremony, he was advised against focusing his acceptance speech on relativity. ^[5]

As the historian of science Marco Mamone Capria noted: “Until the early 1950s, general relativity was a little-frequented subject among physicists; a theory that deserved to be praised, but which could be safely ignored.” ^[6]

The main reason many historians consider it unlikely that General Relativity would have emerged so quickly without Einstein lies in the conceptual radicalism of its hypotheses. The theory did not arise from a gradual accumulation of experimental data, but from an extraordinary combination of physical intuition, geometric imagination, and intellectual audacity. The central idea, that an observer in free fall does not feel gravity, originated from a simple thought experiment. And it required a series of bold conceptual leaps: postulating the equivalence principle as its foundation; generalizing the principle of relativity to all frames of reference, accelerated or not; reimagining gravity not as a force acting in space, but as the curvature of spacetime itself. Furthermore, the concept of curved spacetime necessitated the search for mathematics—Riemannian geometry—virtually unknown to the physicists of his time. And it required moving from the relatively simple equations of flat space to an extraordinarily complex tensor system capable of describing the curvature of spacetime in all directions.

Decades later, this intellectual singularity continues to be recognized. John Wheeler, in the biographical memoir he wrote for the U.S. National Academy of Sciences in 1979, left this message: “If others could give us special relativity, who else but Einstein could have given us general relativity?” ^[7]

More recent researchers, such as Darren Dougan of the University of New South Wales and astrophysicist John K. Webb of the University of Cambridge, have expressed a similar idea: “General relativity was such a gigantic advance that it can be argued that, were it not for Einstein’s formulation, it might have remained undiscovered for a long time.” ^[8]

A world without General Relativity

As physicist Hanoch Gutfreund states, “the general theory of relativity is the foundation of everything we know about the universe” ^[9] . Without it, our understanding of the cosmos would be a fragmented structure riddled with inexplicable anomalies. Modern cosmology, as we know it, simply would not exist: the expansion of the universe and the Big Bang theory arise from the Friedmann-Lemaître equations, which are direct derivations of general relativity. In a world without Einstein, we would probably still imagine a static universe or one governed by a modified Newtonian physics.

In the technological sphere, the absence of this theory would impose critical limitations. The GPS system, essential for global navigation and telecommunications, would be virtually unworkable. Because satellites orbit in a weaker gravitational field, their clocks run at a different rate than Earth’s; without relativity corrections, positioning errors would accumulate at a rate of kilometers per day.

Humanity might have reached the Moon using Newtonian approximations, but many key areas of modern space exploration would be incomprehensible today. The trajectories of interplanetary probes would accumulate systematic errors, and gravity assist maneuvers, essential for exploring the outer solar system, would be far less reliable.

Beyond technology, the greatest loss would be intellectual: we would live in a universe of forces that act mysteriously at a distance, ignoring that space and time form a dynamic and flexible web. The universe would be static, an eternal and indifferent stage, blind to black holes and gravitational waves.

Einstein’s figure is so fascinating to us because it embodies a profoundly human tension: the burning desire to understand in the face of the anguish of a cosmos that seemed to lack meaning. His greatest gift to humanity was not only his equations, but also the courage to confront his own doubts in order to decipher the fabric of the invisible. Like Weir’s navigators, we could have crossed the void with the tools of classical physics, but we would have remained oblivious to the true nature of our journey. Einstein’s work was the testament of a mind that refused to accept silence as an answer, forcing space and time to finally reveal their deepest secret.

Manuel Ribes  . Institute of Life Sciences. Bioethics Observatory. Catholic University of Valencia

***

[1]   Tau Ceti is a  star  in the  constellation  Cetus,  similar to the  Sun  in  mass  and  spectral type . At just under twelve  light-years  from the  solar system , it is a relatively nearby star. The choice of Tau Ceti as a recurring setting in science fiction (from Isaac Asimov to Dan Simmons) is no coincidence. It stems from a unique combination of proximity, similarity to our Sun, and the fact that in 1960 Frank Drake chose it to search for alien radio signals for the first time in history.

[2]   Einstein’s “miracle year” in which he wrote 5 scientific studies that revolutionized physics   BBC News Mundo 16 March 2025

[3]   James Overduin  Einstein’s Spacetime  Gravity Probe B Stanford.edu November 2007 https://einstein.stanford.edu/SPACETIME/spacetime2.html

[4]   John Archibald Wheeler   Albert Einstein Biographical Memoir  National Academy of Sciences. 1980

[5]    Peter Symonds  One hundred years since Albert Einstein’s annus mirabilis  World Socialist Web Site 13 July 2005

“Furthermore, an additional condition was imposed: that the laureate refrain from mentioning his theory of relativity in his Nobel acceptance speech. Had it not been for the King of Sweden, who was in the audience and wished to learn about the theory, Einstein would have been forced to remain silent about his most famous and significant achievement.”

[6]   Marco Mamone Capria   Physics Before and After Einstein  IOS Press 2005 ISBN 1-58603-462-6

[7]  John Archibald Wheeler   Albert Einstein Biographical Memoir  National Academy of Sciences. 1980

[8]   Darren Dougan and John K. Webb Without  Einstein it would have taken decades longer to understand gravity   Newsroom UNSW Sydney 23 Nov 2015

[9]   Alex Winston  Hebrew University’s centennial: Einstein’s legacy and the guardian of a scientific icon   The Canadian Friends of Hebrew University April 2, 2025