The question of whether humanity is alone in the universe remains one of the most profound and enduring mysteries of modern science. While countless efforts have been made to explore this question through astronomical observation and technological innovation, concrete evidence of extraterrestrial civilizations has remained elusive. A fascinating new approach, however, focuses on the role of energy in the potential detection of advanced civilizations. Recent theoretical research proposes that harnessing the immense power of actively feeding black holes could serve as an indicator of extraterrestrial technological advancement—a concept that could offer observable clues from up to 17,000 light-years away.
As civilizations become more technologically sophisticated, their demand for energy increases exponentially. On Earth, humanity’s growing energy needs have evolved in tandem with our progress, ranging from simple mechanical devices powered by natural elements to complex global energy grids. For extraterrestrial civilizations at far greater levels of advancement, their energy requirements would likely dwarf anything we currently comprehend. This idea forms the core of a proposal by Shant Baghram and his team, recently published in The Astrophysical Journal. Their paper theorizes that extraterrestrial civilizations could harvest energy on a colossal scale by feeding matter into a black hole, potentially employing megastructures designed to exploit these cosmic engines of power.
The premise relies on the unique and efficient energy potential of black holes. Specifically, a spinning black hole, known as a Kerr black hole, possesses immense energy in its rotation. Theoretically, advanced beings could devise a system to transfer mass into a black hole in a controlled manner, effectively extracting energy from the accretion disk or the process itself. While highly speculative, this energy-harnessing process would produce detectable signatures observable through electromagnetic radiation, potentially identifiable with current astronomical instruments.
The search for intelligent life in the cosmos is far from new. Humanity’s curiosity about our place in the universe stretches back centuries, inspiring scientists, philosophers, and storytellers alike. Advances in astronomy and space exploration over the last several decades have expanded our capacity to explore this profound question. The discovery of thousands of exoplanets in “habitable zones,” areas around stars where conditions may support liquid water, has spurred speculation that these worlds might host life.
Projects like the Search for Extraterrestrial Intelligence (SETI) have spent decades scanning the skies for artificial radio signals or patterns that might signify technologically advanced civilizations. To date, these efforts have not yielded conclusive evidence. A growing body of researchers has therefore turned toward alternative methods, including looking for indirect evidence of extraterrestrial life based on energy usage patterns or observable artifacts created by civilizations.
This shift in focus draws heavily on the Kardashev Scale, developed by the Soviet astronomer Nikolai Kardashev in 1964. This scale measures civilizations by their energy usage, categorized as follows:
- Type I civilizations harness energy on a planetary scale, similar to humanity’s current trajectory.
- Type II civilizations tap into the energy of their host star, potentially through the construction of enormous energy-harvesting structures like Dyson spheres—hypothetical megastructures that envelop a star and capture its energy output.
- Type III civilizations exploit energy on a galactic scale, utilizing the combined energy of multiple stars or even black holes.
Baghram’s paper takes this framework a step further, introducing a complementary scale based on the extent of a civilization’s space exploration. In their theoretical model, a civilization capable of constructing Dyson spheres around black holes—or even primordial black holes, believed to have formed in the early universe—would represent a highly advanced, energy-driven society.
Dyson spheres have long fascinated scientists and futurists as a plausible means by which advanced civilizations could meet their energy demands. Originally proposed by Freeman Dyson in 1960, these structures could theoretically be detectable by observing anomalies in a star’s light patterns. A Dyson sphere encasing a black hole, however, would emit energy in distinctive ways, likely detectable in the infrared and submillimeter wavelengths.
Baghram’s team identified specific observational methods that could be used to search for such structures. They highlighted instruments like ALMA (the Atacama Large Millimeter/Sub-millimeter Array) as capable of detecting the energy signatures produced by these theoretical megastructures. Observing at distances of up to 5.4 kiloparsecs (around 17,000 light-years), telescopes like ALMA could reveal unusual energy patterns consistent with artificially constructed energy-harnessing systems.
Black holes make an especially compelling target for such investigations. These enigmatic objects are ubiquitous throughout the cosmos, ranging from stellar-mass black holes formed by collapsing stars to supermassive black holes at the centers of galaxies. For primordial black holes, formed shortly after the Big Bang, their existence in regions accessible to advanced civilizations could provide abundant energy harvesting opportunities.
The implications of detecting such a phenomenon are staggering. If we were to observe energy signatures consistent with advanced engineering around a black hole, it would not only confirm the presence of intelligent extraterrestrial life but also provide a glimpse into their level of technological sophistication. Furthermore, studying these structures could expand humanity’s understanding of physics, particularly as it relates to energy systems far beyond our current capabilities.
Despite its promise, this approach faces significant challenges. First, the theoretical nature of the proposal means that observational confirmation requires not only exceptional precision in measurement but also a high degree of certainty in distinguishing artificial energy signatures from natural astrophysical phenomena. Space is filled with energetic processes that could mimic the signatures Baghram and his team describe, necessitating extensive analysis to rule out false positives.
Additionally, the distance involved in observing structures potentially thousands or tens of thousands of light-years away presents a major hurdle. Even advanced telescopes like ALMA, while immensely powerful, are limited in their sensitivity and range. Future advancements in telescope technology, particularly those capable of resolving finer details and detecting faint signals, may be necessary to test these theories definitively.
Beyond technical limitations, this framework also assumes that any advanced civilization would share similar approaches to energy harnessing and usage. Human theories about extraterrestrial life are inherently limited by the lens of our own technological and scientific paradigms. Civilizations fundamentally different from our own might approach energy generation and utilization in ways entirely outside our current understanding, making their detection an even greater challenge.
Nevertheless, Baghram’s proposal injects new energy and creativity into the search for extraterrestrial intelligence. By thinking beyond traditional communication signals and delving into energy-based signatures, this approach reflects the versatility and adaptability that have come to define modern astronomy. The idea that black holes could serve not only as engines of destruction but as conduits of discovery speaks to the transformative potential of scientific inquiry.
As humanity continues to grapple with existential questions about our place in the universe, efforts like these remind us that the quest for knowledge knows no boundaries. By examining how civilizations might innovate to meet their needs, we gain not only a framework for detecting extraterrestrial life but also a renewed sense of wonder about our capacity for imagination and discovery. Should evidence of these energy megastructures be found, it would be one of the most transformative scientific breakthroughs of all time—a discovery not just of other life but of our shared connection as intelligent beings navigating the cosmos.
Reference: Shant Baghram, In Search of Extraterrestrial Artificial Intelligence Through Dyson Sphere–like Structures around Primordial Black Holes, The Astrophysical Journal (2025). DOI: 10.3847/1538-4357/ad9b10