The Alternate View
Future Trajectories for Civilizations
By John G. Cramer
Those involved in the search for intelligent extraterrestrial civilizations (SETI) have found it convenient to extrapolate from the growth trajectory of our present human civilization on Planet Earth into the future, particularly the next millennium, to assume that extraterrestrial civilizations might follow a similar path, and to consider detectable signals from such civilizations. One famous example is Freeman Dyson’s 1959 concept of a star-engulfing Dyson Sphere, constructed by an advanced civilization to intercept all output energy of their parent star and to re-radiate a fraction as waste heat, detectable from its low emission of visible light and its high emission of infrared radiation.
Another example is the pioneering work of Nikolai Kardashev (1964) and follow-up consideration by Carl Sagan (1980) in classifying the technological level of possible advanced civilizations by their energy consumption. Sagan invented the “Kardashev index,” defined as K=[Log10(P)—6]/10, where P is the total power in watts used by the civilization. (See AV 215 in the Nov/Dec 2021Analog.) The present level of our civilization on this scale is about K=0.731. We are not yet even a Type 1 Kardashev civilization, but our total power consumption is growing at a rate of about 2.2% per year. If that rate continued, we would reach K=1.0 in 285 years and K=2.0 in 1,340 years. However, both extrapolations are questionable because our present rate of energy consumption cannot continue for a millennium. About 79% of our presently used energy comes from burning coal, oil, and gas fossil fuels. Those energy resources are limited. They are running out while polluting the atmosphere with greenhouse-generating CO2, and they are accelerating global warming and climate change to a crisis looming in the next decade.
Kardashev assumed for simplicity that energy consumption directly indicates the technological level of a civilization like ours. He also assumed that it would grow without interruption at about the rate of about 1% per year. Those assumptions are naive. Technological developments can radically change the efficiency of energy use, and events like recessions, wars, pandemics, poor political leadership, and global disasters can have a dramatic effect on energy-use growth rates. On a thousand-year time scale, we know from our own historical record that civilizations rise, decline, collapse, and even disappear. Can we depend on technologically advanced civilizations, our own and others, to grow smoothly and continuously on a thousand-year time scale?
This question leads us to two recent papers on the detection of extraterrestrial civilizations, both written by scientists associated with Seattle’s Blue Marble Space Institute of Science. They use a form of scenario modeling that is new in my experience and seems to have been invented and used by the Norwegian Defense Research Establishment.
The first of these two papers focuses on defining various possible scenarios for the stability and evolution of technological civilizations. The authors use a double parameterization to describe realistic scenarios for possible future developments of such civilizations. They suggest that the stability and technological growth of a global civilization should depend on two elements, (1) societal structure and (2) technological level and structure. Scoring well with both elements should make an extraterrestrial civilization more detectable.
They parameterize societal element (1) using three factors: (X) availability of resources (Y) form of government, and (Z) organization of society. Resources are either (1) scarce or (2) abundant. Form of government can be (1) governed by a single individual (dictatorship), (2) governed by a small number of individuals (oligarchy), (3) governed by the entire populace (democracy), or (4) no government at all (anarchy). Society may either be (1) organized as a global hierarchy, or (2) distributed over many organized independent and semi-independent subgroups.
There 2 x 4 x 2 = 16 possible combinations of these parameter values. However, some of these 16 combinations are mutually inconsistent, so we can exclude 11 combinations, leaving only (X,Y,Z) = (1,1,1), (1,2,1), (1,4,2), (2,3,2), and (1,4,2). For simplicity, the authors chose to exclude the two anarchy scenarios (Y=4) and focus on just three global scenarios:
GF1(1,1,1) Philosopher-King Civilization
GF2(1,2,1) Survival-of-the Fittest Civilization
GF3(2,3,2) Pure-Democracy Civilization
They assert that our Earth’s present civilization, with its scarcity of resources and its governments that are strongly influenced by a few wealthy individuals and corporations, seems to best match scenario GF2, the “Survival-of-the-Fittest” civilization.
The authors make the distinction between the biosphere, the totality of the planet’s living systems and their interactions with the planet’s physical environment, representing the biological component of the planetary system, and the technosphere, the totality of inhabitant-made technological systems, infrastructures, artifacts, and their material and energetic flows, considered as a planetary-scale system intertwined with society. The relationship between these two spheres provides a five-element parameter set for characterizing the technological state of the civilization. The five factors are: (A) the relationship of the biosphere to the technosphere and, (B) the technosphere’s the spatial distribution, (C) the nature of the technosphere’s development, (D) the highest order of technology reached by the technosphere, and (E) the smallest scale of interconnected subsystems of the technology.
The relationship of biosphere to technosphere (A) may be: (1) the biosphere and technosphere are the same, (2) the biosphere is a subset of the technosphere, (3) the technosphere is a subset of the biosphere, (4) the biosphere and technosphere have some common elements while not equal, and (5) the biosphere and technosphere have no common elements.
The spatial distribution of the technosphere (B) is considered on a planetary scale and may be: (1) the technosphere is all at a central location (e.g., Earth), (2) the technosphere is at two locations (Earth + Moon), (3) the technosphere is at more than two locations (Earth + Moon + Mars + Asteroids), and (4) the technosphere is everywhere and not localized at all.
The technosphere’s development (C) maybe: (1) evolved and emergent, or (2) designed and directed, i.e., technological research and development that is centrally planned and structured. The order (D) of the technosphere involves its purpose, which may be: (1) helping humans interact with the technological realm, (2) helping humans interact with the otherwise inaccessible symbolic realm, or (3) helping autonomous technological agents interact with the technological and symbolic realms without the participation of humans.
The final factor is the smallest technological scale of the connections and interdependences of the technosphere, which may be (1) less than 1 nm, (2) 1 nm to 1 μm, or (3) more than 1 μm. Our present technology on Earth, in these terms, is (A,B,C,D,E) = (4,1,1,2,2).
There are 5 x 4 x 2 x 3 x 3 = 360 possible combinations of these technological structure parameters. As with societal parameters, some of the combinations of technological structure parameters are mutually incompatible. In particular, incompatibilities are present in 42 combinations, leaving 63 combinations that are consistent.
From among these many possible technological scenarios, the authors selected 11 possible technological scenarios that are of particular interest:
TF1(1,1,1,1,2)Environmental Sustainability
TF2(2,2,2,2,2)Planetary Engineering
TF3(3,1,1,1,2)Environmental Sustainability
TF4(4,1,1,1,2)Simplicity
TF5(4,1,1,2,2)Earth 2024
TF6(5,2,2,2,2)Living Parallel to Machines
TF7(5,2,2,3,2)Living Parallel to Machines
TF8(5,4,2,3,1)Technology Flees Earth
TF9(5,3,2,2,2)Living Parallel to Machines
TF10(5,3,2,3,2)Living Parallel to Machines
TF11(5,4,2,3,2)Technology Flees Earth
The question is then, which of the 3 sociological scenarios are compatible with the 11 technological scenarios? The authors conclude that 16 of the 33 combinations are compatible, and they select 10 of these scenarios for further study (See Table 1):
The second paper takes these 10 scenarios and uses a Monte Carlo simulation to test them for stability and to estimate their SETI detectability by a distant civilization. According to their simulation, all of the scenarios that have resource scarcity (GF1 or GF2) are unstable and subject to global economic crashes, sometimes followed by recoveries. Only scenarios S3, S5, and S10 are free of collapse cycles, with the others exhausting resources and, even with some recovery, never returning to their previous technological levels. The paper presents a pessimistic prediction of the future of our civilization, particularly in view of the present trends away from conservation and renewable resources.
Their conclusions on the SETI detectability of hypothetical extraterrestrial civilizations following these scenarios are also rather pessimistic. They cite the term fL in the Drake equation (See AV 102 in the September 2000 Analog.), which characterizes the time window during which a civilization is detectable. Previous SETI work has usually assumed that this value is continuous and rather large. However, this work points to cyclic collapse and recovery and asserts that there should be an “effective time window” given by fL = Dc Tspan, where Dc is the mean duty cycle for detectability, and Tspan is the observation window (1,000 years in these simulations). In the simulations, the scarce-resource civilizations collapse about every 200 years, leading to a duty cycle value around D = 0.5.
They conclude by considering various detectable atmospheric pollutant techno-signatures of an industrial civilization, like nitrogen dioxide (NO2), trichlorofluoromethane (CFC-11), dichlorodifluoromethane (CFC-12), and carbon tetrafluoride (CF4). Some of these are long-lived and may be present long after the civilization that produced them has collapsed and ceased their production
Th e bottom line of these two studies is that (1) the Fermi Paradox Great Silence may be in part the result of the short detection windows for unstable planetary civilizations, and (2) our present society (scenario S2) is fragile and subject to collapse, so we should be doing much more to stabilize and preserve it, and also to prepare for recovery after its collapse.
Hard SF Novels: John’s new third hard SF novel, Fermi’s Question, and its prequel, Einstein’s Bridge, are available as eBooks from Baen Books at: https://www.baen.com/einstein-s-bridge.html. His first hard SF novel Twistor, is available online from Amazon.
Non-Fiction Books: John’s new book, How to Live Much Longer: The Mitochondrial DNA Connection (Springer Copernicus, May 2026) can be ordered online from Amazon or Springer. His book on his transactional interpretation of QM, The Quantum Handshake: Entanglement, Nonlocality, and Transactions (Springer, January 2016), is also available from Amazon or Springer.
Alternate View Columns Online: Electronic reprints of 243 or more of “The Alternate View” columns written by John G. Cramer and previously published in Analog are currently available online at: http:// www.npl.washington.edu/av.
References:
Freeman J. Dyson, “Search for Artificial Stellar Sources of Infrared Radiation”, Science 131, 1667 (1960) and “Artificial Biosphere”, Science 132, 252 (1960).
- S. Kardashev, “Transmission of Information by Extraterrestrial Civilizations”, (translation) Soviet Astronomy-AJ 8 2, 217—221 (1964).
Carl Sagan, The Cosmic Connection: An Extraterrestrial Perspective, Anchor Books (1980); ISBN-10: 0440133017.
Iver Johansen, “Scenario modelling with morphological analysis,” Technological Forecasting & Social Change 126, 116—125 (2018).
- Haqq-Misra, G. Profitiliotis, and R. K. Kopparapu, “Projections of Earth’s Technosphere: Scenario Modeling, Worldbuilding, and Overview of Remotely Detectable Technosignatures,” Technological Forecasting and Social Change 218, 124—194 (2025); https://arxiv.org/pdf/2409.00067.
- Blanco, J. Haqq-Misra, and G. Profitiliotis, “Projections of Earth’s Technosphere: Civilization Collapse-Recovery Dynamics and Detectability,” (2026 preprint) https://arxiv.org/pdf/2604.13774.