A matrioshka brain
is a hypothetical
megastructure of immense computational capacity powered by a
Dyson sphere. It was proposed in 1997 by Robert J. Bradbury (1956–2011). It is an example of a class-B
stellar engine, employing the entire energy output of a star to drive
computer systems.
This concept derives its name from the nesting Russian
matryoshka dolls.
The concept was deployed by Bradbury in the anthology ''Year Million: Science at the Far Edge of Knowledge''.
Concept
The concept of a matrioshka brain comes from the idea of using Dyson spheres to power an enormous, star-sized computer. The term "matrioshka brain" originates from
matryoshka dolls, which are wooden Russian nesting dolls. Matrioshka brains are composed of several Dyson spheres nested inside one another, the same way that matryoshka dolls are composed of multiple nested doll components.

The innermost Dyson sphere of the matrioshka brain would draw energy directly from the star it surrounds and give off large amounts of
waste heat while computing at a high temperature. The next surrounding Dyson sphere would absorb this waste heat and use it for its computational purposes, all while giving off waste heat of its own. This heat would be absorbed by the next sphere, and so on, with each sphere radiating at a lower temperature than the one before it. For this reason, Matrioshka brains with more nested Dyson spheres would tend to be more efficient, as they would waste less heat energy. The inner shells could run at nearly the same temperature as the star itself, while the outer ones would be close to the temperature of interstellar space. The engineering requirements and resources needed for this would be enormous.
Jupiter Brain
The term "matrioshka brain" was invented by Robert Bradbury as an alternative to the Jupiter brain
—a concept similar to the matrioshka brain, but on a smaller planetary scale and optimized for minimal signal
propagation delay. A matrioshka brain design is concentrated on sheer capacity and the maximum amount of energy extracted from its source star, while a Jupiter brain is optimized for computational speed. Jupiter brain is related to the idea of the hypothetical material
computronium, which could be enmassed to sizes of entire planets and even stars.
Possible uses
Some possible uses of such an immense computational resource have been proposed.
* An idea suggested by
Charles Stross, in his novel
''Accelerando'', would be to use it to run perfect simulations or
uploads of human minds into
virtual reality
Virtual reality (VR) is a simulated experience that employs pose tracking and 3D near-eye displays to give the user an immersive feel of a virtual world. Applications of virtual reality include entertainment (particularly video games), e ...
spaces supported by the matrioshka brain. Stross even went as far as to suggest that a sufficiently powerful species utilizing enough raw processing power could launch attacks upon, and manipulate, the structure of the universe itself.
* In ''Godplayers'' (2005),
Damien Broderick
Damien Francis Broderick (born 22 April 1944) is an Australian science fiction and popular science writer and editor of some 74 books. His science fiction novel ''The Dreaming Dragons'' (1980) introduced the trope of the generation time machine ...
surmises that a matrioshka brain would allow simulating entire alternate universes.
* The
futurist and
transhumanist author
Anders Sandberg wrote an essay speculating on implications of computing on the massive scale of machines such as the matrioshka brain, published by the
Institute for Ethics and Emerging Technologies.
* Matrioshka brains and other
megastructures are a common theme in the
fictional
Fiction is any creative work, chiefly any narrative work, portraying individuals, events, or places that are imaginary, or in ways that are imaginary. Fictional portrayals are thus inconsistent with history, fact, or plausibility. In a traditio ...
Orion's Arm universe, where they are used by
superintelligences as processing nodes connected by artificial
wormhole
A wormhole ( Einstein-Rosen bridge) is a hypothetical structure connecting disparate points in spacetime, and is based on a special solution of the Einstein field equations.
A wormhole can be visualized as a tunnel with two ends at separate p ...
s.
* The
Dennis E. Taylor novel
Heavens River mentions building a Matrioshka brain for use with replicant and artificial intelligence
See also
*
Artificial general intelligence
Artificial general intelligence (AGI) is the ability of an intelligent agent to understand or learn any intellectual task that a human being can.
It is a primary goal of some artificial intelligence research and a common topic in science fict ...
*
Astronomical engineering
*
Computronium
*
Dyson sphere
*
Kardashev scale
*
Megascale engineering
*
Omega Point
*
Technological singularity
The technological singularity—or simply the singularity—is a hypothetical future point in time at which technological growth becomes uncontrollable and irreversible, resulting in unforeseeable changes to human civilization. According to the m ...
References
External links
*
*
*
Megaminds, abstract evolution and the consistency machine, aka how to build simulated realities
* Gorman, A. C. (2014
"The Anthropocene in the Solar System" Journal of Contemporary Archaeology.
Human Brain and Universe - Similar Shapes? ScienceAlert (2020).
{{Science fiction
Fictional computers
Megastructures
Exploratory engineering
Hypothetical technology
Fiction about stars