Dyson sphere

Last updated

Freeman Dyson, the first scientist to explore the concept Freeman dyson (detail).jpg
Freeman Dyson, the first scientist to explore the concept

A Dyson sphere is a hypothetical megastructure that encompasses a star and captures a large percentage of its solar power output. [1] [2] [3] The concept is a thought experiment that attempts to imagine how a spacefaring civilization would meet its energy requirements once those requirements exceed what can be generated from the home planet's resources alone. Because only a tiny fraction of a star's energy emissions reaches the surface of any orbiting planet, building structures encircling a star would enable a civilization to harvest far more energy.

Contents

The first modern imagining of such a structure was by Olaf Stapledon in his science fiction novel Star Maker (1937). The concept was later explored by the physicist Freeman Dyson in his 1960 paper "Search for Artificial Stellar Sources of Infrared Radiation". Dyson speculated that such structures would be the logical consequence of the escalating energy needs of a technological civilization and would be a necessity for its long-term survival. A signature of such spheres detected in astronomical searches could be an indicator of extraterrestrial life.

Since Dyson's paper, many variant designs involving an artificial structure or series of structures to encompass a star have been proposed in exploratory engineering or described in science fiction, often under the name "Dyson sphere". Fictional depictions often describe a solid shell of matter enclosing a star – an arrangement considered by Dyson himself to be impossible.

Origins

Inspired by the 1937 science fiction novel Star Maker by Olaf Stapledon, [4] the physicist and mathematician Freeman Dyson was the first to formalize the concept of what became known as the "Dyson sphere" in his 1960 Science paper "Search for Artificial Stellar Sources of Infra-Red Radiation". Dyson theorized that as the energy requirements of an advanced technological civilization increased, there would come a time when it would need to systematically harvest the energy from its local star on a large scale. He speculated that this could be done via a system of structures orbiting the star, designed to intercept and collect its energy. He argued that as the structure would result in the large-scale conversion of starlight into far-infrared radiation, an earth-based search for sources of infrared radiation could identify stars supporting intelligent life. [5]

Dyson did not detail how such a system could be constructed, simply referring to it in the paper as a 'shell' or 'biosphere'. He later clarified that he did not have in mind a solid structure, saying "A solid shell or ring surrounding a star is mechanically impossible. The form of 'biosphere' which I envisaged consists of a loose collection or swarm of objects traveling on independent orbits around the star". [6] Such a concept has often been referred to as a Dyson swarm; [7] however, in 2013, Dyson said that he had come to regret that the concept had been named after him. [8]

Search for megastructures

Dyson-style energy collectors around a distant star would absorb and re-radiate energy from the star. The wavelengths of such re-radiated energy may be atypical for the star's spectral type, due to the presence of heavy elements not naturally occurring within the star. If the percentage of such atypical wavelengths were to be significant, an alien megastructure could be detected at interstellar distances. [5] This could indicate the presence of what has been called a Type II Kardashev civilization. [9]

SETI has looked for such infrared-heavy spectra from solar analogs, as has Fermilab. [10] [11] Fermilab discovered 17 potential "ambiguous" candidates, of which four were in 2006 called "amusing but still questionable". [10] Later searches also resulted in several candidates, all of which remain unconfirmed. [12] [13] [14]

On 14 October 2015, Planet Hunters' citizen scientists discovered unusual light fluctuations of the star KIC 8462852 raising press speculation that a Dyson sphere may have been discovered. [15] [16] However, subsequent analysis showed that the results were consistent with the presence of dust. [17] [18]

A further campaign found evidence of seven possible candidates for Dyson-spheres. However further investigation is required.

These candidates are

Gaia DR3 IDDistance (ly)MagnitudeRA (ICRS)Dec (ICRS)
3 496 509 309 189 181 184466.1 ± 3.315.9912h45m12.94s-26°52'03.28"
4 843 191 593 270 342 656690.2 ± 11.417.713h56m03.81s-40°31'48.52"
4 649 396 037 451 459 712715.6 ± 20.218.394h56m03.05s-74°10'14.16"
2 660 349 163 149 053 824689.8 ± 18.917.6623h27m51.29s5°06'26.14"
3 190 232 820 489 766 656896 ± 19.917.004h02m07.8s-10°54'40.73"
2 956 570 141 274 256 512864.3 ± 8.516.325h13m46.51s-25°11'11.49"
2 644 370 304 260 053 376815.1 ± 12.116.4823h35m32.44s-0°04'25"

[19]

Feasibility and science-based speculation

Although Dyson sphere systems are theoretically possible, building a stable megastructure around the Sun is currently far beyond humanity's engineering capacity. The number of craft required to obtain, transmit, and maintain a complete Dyson sphere exceeds present-day industrial capabilities. George Dvorsky has advocated the use of self-replicating robots to overcome this limitation in the relatively near term. [20] Some have suggested that Dyson sphere habitats could be built around white dwarfs [21] and even pulsars. [22]

Stellar engines are hypothetical megastructures whose purpose is to extract useful energy from a star, sometimes for specific purposes. For example, Matrioshka brains have been proposed to extract energy for computation, while Shkadov thrusters would extract energy for propulsion. Some proposed stellar engine designs are based on the Dyson sphere. [23] [24]

Fictional accounts

A precursor to the concept of Dyson spheres was featured in the 1937 novel Star Maker by Olaf Stapledon, [1] in which he described "every solar system... surrounded by a gauze of light-traps, which focused the escaping solar energy for intelligent use"; [25] Dyson got his inspiration from this book and suggested that "Stapledon sphere" would be a more apt name for the concept. [26] Fictional Dyson spheres are typically solid structures forming a continuous shell around the star in question, although Dyson himself considered that prospect to be mechanically implausible. [2] [3] They are sometimes used as the type of plot device known as a Big Dumb Object. [27]

Dyson spheres appear as a background element in many works of fiction, including the 1964 novel The Wanderer by Fritz Leiber where aliens enclose multiple stars in this way. [1] [27] [28] Dyson spheres are depicted in the 1975–1983 book series Saga of Cuckoo by Frederik Pohl and Jack Williamson, and one functions as the setting of Bob Shaw's 1975 novel Orbitsville and its sequels. [2] [3] In the 1992 episode "Relics" of the TV show Star Trek: The Next Generation , [29] the USS Enterprise finds itself trapped in an abandoned Dyson Sphere; [30] [31] in a 2011 interview, Dyson said that he enjoyed the episode, although he considered the sphere depicted to be "nonsense". [32] Michael Jan Friedman who wrote the novelization observed that in the TV episode itself the Dyson sphere was effectively a MacGuffin, with "just nothing about it" in the story, and decided to flesh out the plot element in his novelization. [33] :ix

Other science-fiction story examples include Tony Rothman's The World Is Round, Somtow Sucharitkul's Inquisitor series, Timothy Zahn's Spinneret, James White's Federation World, Stephen Baxter's The Time Ships , and Peter F. Hamilton's Pandora's Star. [1] :133 Variations on the Dyson Sphere concept include a single circular band in Larry Niven's 1970 novel Ringworld , [3] [34] [35] a half sphere in the 2012 novel Bowl of Heaven by Gregory Benford and Niven, [2] [3] and nested spheres—also known as a Matrioshka brain—in Colin Kapp's 1980s Cageworld series and Brian Stableford's 1979–1990 Asgard trilogy. [1] [3]

Stableford himself observed that Dyson spheres are usually MacGuffins or largely deep in the backgrounds of stories, giving as examples Fritz Leiber's The Wanderer and Linda Nagata's Deception Well, whereas stories involving space exploration tend to employ the variants like Niven's Ringworld. [1] :133He gives two reasons for this: firstly that Dyson spheres are simply too big to address, which Friedman also alluded to when pointing out that the reason that his novelization of "Relics" did not go further into the sphere was that it was only 400 pages and he had just shy of 4 weeks to write it; and secondly that, especially for hard science-fiction, Dyson spheres have certain engineering problems that complicate stories. [1] :133 [33] :ix In particular, since gravitational attraction is in equilibrium inside such a sphere (per the shell theorem), other means such as rotating the sphere have to be employed in order to keep things attached to the interior surface, which then leads to the problem of a gravity gradient that goes to zero at the rotational poles. [1] :133 Authors address this with various modifications of the idea such as the aforementioned Cageworld nesting, Dan Alderson's double sphere idea, and Niven's reduced Ringworld (discussed in "Bigger Than Worlds"). [1] :133

See also

Related Research Articles

<span class="mw-page-title-main">Freeman Dyson</span> British theoretical physicist and mathematician (1923–2020)

Freeman John Dyson was a British-American theoretical physicist and mathematician known for his works in quantum field theory, astrophysics, random matrices, mathematical formulation of quantum mechanics, condensed matter physics, nuclear physics, and engineering. He was professor emeritus in the Institute for Advanced Study in Princeton and a member of the board of sponsors of the Bulletin of the Atomic Scientists.

<span class="mw-page-title-main">Kardashev scale</span> Measure of a civilizations evolution

The Kardashev scale is a method of measuring a civilization's level of technological advancement based on the amount of energy it is capable of harnessing and using. The measure was proposed by Soviet astronomer Nikolai Kardashev (1932–2019) in 1964 and was named after him.

<i>Star Maker</i> 1937 Olaf Stapledon novel

Star Maker is a science fiction novel by British writer Olaf Stapledon, published in 1937. The book describes a history of life in the universe, dwarfing in scale Stapledon's previous book, Last and First Men (1930), a history of the human species over two billion years. Star Maker tackles philosophical themes such as the essence of life, of birth, decay and death, and the relationship between creation and creator. A pervading theme is that of progressive unity within and between different civilisations.

Star lifting is any of several hypothetical processes by which a sufficiently advanced civilization could remove a substantial portion of a star's matter which can then be re-purposed, while possibly optimizing the star's energy output and lifespan at the same time. The term appears to have been coined by David Criswell.

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.

<span class="mw-page-title-main">Alderson disk</span> Hypothetical artificial solar megastructure

An Alderson disk is a hypothetical artificial astronomical megastructure, like Larry Niven's Ringworld and the Dyson sphere. The disk is a giant platter with a thickness of several thousand miles. The Sun rests in the hole at the center of the disk. The outer perimeter of an Alderson disk would be roughly equivalent to the orbit of Mars or Jupiter. According to the proposal, a sufficiently large disk would have a larger mass than its Sun.

Xenoarchaeology, a branch of xenology dealing with extraterrestrial cultures, is a hypothetical form of archaeology that exists mainly in works of science fiction. The field is concerned with the study of the material remains to reconstruct and interpret past life-ways of alien civilizations. Xenoarchaeology is not currently practiced by mainstream archaeologists due to the current lack of any material for the discipline to study.

<span class="mw-page-title-main">Megastructure</span> Very large artificial object

A megastructure is a very large artificial object, although the limits of precisely how large vary considerably. Some apply the term to any especially large or tall building. Some sources define a megastructure as an enormous self-supporting artificial construct. The products of megascale engineering or astroengineering are megastructures.

Megascale engineering is a form of exploratory engineering concerned with the construction of structures on an enormous scale. Typically these structures are at least 1,000 km (620 mi) in length—in other words, at least one megameter, hence the name. Such large-scale structures are termed megastructures.

<span class="mw-page-title-main">Stellar engine</span> Class of hypothetical megastructures

Stellar engines are a class of hypothetical megastructures which use the resources of a star to generate available work. For instance, they can use the energy of the star to produce mechanical, electrical or chemical work or they can use the impulse of the light emitted by the star to produce thrust, able to control the motion of a star system. The concept has been introduced by Bădescu and Cathcart. The variants which produce thrust may accelerate a star and anything orbiting it in a given direction. The creation of such a system would make its builders a type-II civilization on the Kardashev scale.

<i>Accelerando</i> 2005 science fiction novel by Charles Stross

Accelerando is a 2005 science fiction novel consisting of a series of interconnected short stories written by British author Charles Stross. As well as normal hardback and paperback editions, it was released as a free e-book under the CC BY-NC-ND license. Accelerando won the Locus Award in 2006, and was nominated for several other awards in 2005 and 2006, including the Hugo, Campbell, Clarke, and British Science Fiction Association Awards.

<span class="mw-page-title-main">Dyson tree</span> Hypothetical genetically-engineered plant capable of growing inside a comet

A Dyson tree is a hypothetical genetically engineered plant capable of growing inside a comet, suggested by the physicist Freeman Dyson. Plants may be able to produce a breathable atmosphere within the hollow spaces of the comet, utilising solar energy for photosynthesis and cometary materials for nutrients, thus providing self-sustaining habitats for humanity in the outer solar system analogous to a greenhouse in space, a shell grown by a mollusc or the actions of thermogenic plants, such as the skunk cabbage or the voodoo lily.

Stellar engineering is a type of engineering concerned with creating or modifying stars through artificial means.

An infrared excess is a measurement of an astronomical source, typically a star, that in their spectral energy distribution has a greater measured infrared flux than expected by assuming the star is a blackbody radiator. Infrared excesses are often the result of circumstellar dust heated by starlight and reemitted at longer wavelengths. They are common in young stellar objects and evolved stars on the asymptotic giant branch or older.

<span class="mw-page-title-main">Supernovae in fiction</span>

Supernovae, extremely powerful explosions of stars, have been featured in works of fiction since at least the early 1900s.

Engineering on an astronomical scale, or astronomical engineering, i.e., engineering involving operations with whole astronomical objects, is a known theme in science fiction, as well as a matter of recent scientific research and exploratory engineering.

<span class="mw-page-title-main">Technosignature</span> Property that provides scientific evidence for the presence of technology

Technosignature or technomarker is any measurable property or effect that provides scientific evidence of past or present technology. Technosignatures are analogous to biosignatures, which signal the presence of life, whether intelligent or not. Some authors prefer to exclude radio transmissions from the definition, but such restrictive usage is not widespread. Jill Tarter has proposed that the search for extraterrestrial intelligence (SETI) be renamed "the search for technosignatures". Various types of technosignatures, such as radiation leakage from megascale astroengineering installations such as Dyson spheres, the light from an extraterrestrial ecumenopolis, or Shkadov thrusters with the power to alter the orbits of stars around the Galactic Center, may be detectable with hypertelescopes. Some examples of technosignatures are described in Paul Davies's 2010 book The Eerie Silence, although the terms "technosignature" and "technomarker" do not appear in the book.

<span class="mw-page-title-main">Planetary civilization</span> Civilization capable of using all of the energy on its planet

A planetary civilization or global civilization is a civilization of Type I on the Kardashev scale. This type of civilization is likely to be reliant on renewable energy sources such as stellar power, as well as powerful non-renewable sources such as nuclear fusion. A Type I civilization's energy consumption level is roughly equivalent to the solar insolation on Earth (between 1016 and 1017 watts) – around 3 orders of magnitude higher than that of contemporary humanity (around 2×1013 as of 2020).

<i>Rendezvous with the Future</i> 2022 TV series or program

Rendezvous with the Future is a documentary series commissioned by Bilibili and produced by BBC Studios which explores the science behind the science fiction of author Liu Cixin. The series premiered in China on 16 November 2022 and has been watched by a combined audience of more than 80 million.

<span class="mw-page-title-main">Artificial planet</span> Proposed stellar megastructure

An artificial planet is a proposed stellar megastructure. Its defining characteristic is that it has sufficient mass to generate its own gravity field that is strong enough to prevent atmosphere from escaping, although the term has been sometimes used to describe other types of megastructures that have self-sufficient ecosystems. The concept can be found in many works of science-fiction.

References

  1. 1 2 3 4 5 6 7 8 9 Stableford, Brian M. (2006). "Dyson, Freeman (John) (1923–)". Science Fact and Science Fiction: An Encyclopedia . Taylor & Francis. pp. 132–133. ISBN   978-0-415-97460-8.
  2. 1 2 3 4
  3. 1 2 3 4 5 6 Clute, John; Langford, David; Sleight, Graham (eds.). "Dyson Sphere". The Encyclopedia of Science Fiction (4th ed.). Archived from the original on 2011-10-28. Retrieved 2021-11-18.
  4. Dyson, Freeman (1979). Disturbing the Universe. Basic Books. p. 211. ISBN   978-0-465-01677-8. Some science fiction writers have wrongly given me the credit of inventing the artificial biosphere. In fact, I took the idea from Olaf Stapledon, one of their own colleagues
  5. 1 2 Freeman J. Dyson (1960). "Search for Artificial Stellar Sources of Infrared Radiation". Science . 131 (3414): 1667–1668. Bibcode:1960Sci...131.1667D. doi:10.1126/science.131.3414.1667. PMID   17780673. S2CID   3195432.
  6. Dyson, F. J.; Maddox, J.; Anderson, P; Sloane, E. A. (1960). "Letters and Response, Search for Artificial Stellar Sources of Infrared Radiation". Science . 132 (3421): 250–253. doi:10.1126/science.132.3421.252-a. PMID   17748945.
  7. Smith, Jack (2020). "Review and viability of a Dyson Swarm as a form of Dyson Sphere". Physica Scripta . 97 (12): 122001. arXiv: 2109.11443 . doi: 10.1088/1402-4896/ac9e78 . S2CID   237605010.
  8. "STARSHIP CENTURY SYMPOSIUM, MAY 21 - 22, 2013". 7 July 2013. Archived from the original on 7 July 2013. Retrieved 31 August 2017.
  9. Kardashev, Nikolai. "On the Inevitability and the Possible Structures of Supercivilizations", The search for extraterrestrial life: Recent developments; Proceedings of the Symposium, Boston, MA, June 18–21, 1984 (A86-38126 17–88). Dordrecht, D. Reidel Publishing Co., 1985, p. 497–504.
  10. 1 2 Carrigan, D. (February 23, 2006). "Fermilab Dyson Sphere search program". Fermi National Accelerator Laboratory. Archived from the original on 2006-03-06. Retrieved 2006-03-02.
  11. Shostak, Seth (Spring 2009). "When Will We Find the Extraterrestrials?" (PDF). Engineering & Science. 72 (1): 12–21. ISSN   0013-7812. Archived from the original (PDF) on 2015-04-15.
  12. Dick Carrigan (2010-12-16). "Dyson Sphere Searches". Home.fnal.gov. Retrieved 2012-06-12.
  13. Billings, Lee. "Alien Supercivilizations Absent from 100,000 Nearby Galaxies". Scientific American . Retrieved 31 August 2017.
  14. "Infra digging: Looking for aliens: The search for extraterrestrials goes intergalactic". The Economist. 2015-04-18. Retrieved 2015-04-19. Fifty [galaxies] were red enough to be hosting aliens gobbling up half or more of their starlight.
  15. Andersen, Ross (13 October 2015). "The Most Mysterious Star in Our Galaxy". The Atlantic . Retrieved 13 October 2015.
  16. Williams, Lee (15 October 2015). "Astronomers may have found giant alien 'megastructures' orbiting star near the Milky Way". The Independent . Retrieved 15 October 2015.
  17. Boyajian, Tabetha S.; et al. (2018). "The First Post-Kepler Brightness Dips of KIC 8462852". The Astrophysical Journal. 853 (1). L8. arXiv: 1801.00732 . Bibcode:2018ApJ...853L...8B. doi: 10.3847/2041-8213/aaa405 . S2CID   215751718.
  18. Drake, Nadia (3 January 2018). "Mystery of 'Alien Megastructure' Star Has Been Cracked". National Geographic . Archived from the original on January 3, 2018. Retrieved 4 January 2018.
  19. Suazo, Matías; et al. (6 May 2024). "Project Hephaistos – II. Dyson sphere candidates from Gaia DR3, 2MASS, and WISE". Monthly Notices of the Royal Astronomical Society. 531 (1): 695–707. doi:10.1093/mnras/stae1186.
  20. Dvorsky, George (2012-03-20). "How to build a Dyson sphere in five (relatively) easy steps" . Retrieved 2016-10-07.
  21. Semiz, İbrahim; Oğur, Salim (2015). "Dyson Spheres around White Dwarfs". arXiv: 1503.04376 [physics.pop-ph].
  22. Osmanov, Z. (2015). "On the search for artificial Dyson-like structures around pulsars". Int. J. Astrobiol. 15 (2): 127–132. arXiv: 1505.05131 . Bibcode:2016IJAsB..15..127O. doi:10.1017/S1473550415000257. S2CID   13242388.
  23. "Stellar engine". The Internet Encyclopedia of Science. Retrieved 2007-10-08.
  24. Badescu, Viorel; Richard B. Cathcart. "Space travel with solar power and a dyson sphere". Astronomy Today. Archived from the original on 2012-02-04. Retrieved 2007-10-07.
  25. Tate, Karl (14 January 2014). "Dyson Spheres: How Advanced Alien Civilizations Would Conquer the Galaxy". Space.com . Retrieved January 14, 2014.
  26. Sudbery, Tony; Langford, David (2022). "Dyson, Freeman J". In Clute, John; Langford, David; Sleight, Graham (eds.). The Encyclopedia of Science Fiction (4th ed.). Retrieved 2024-03-20.
  27. 1 2 Pringle, David, ed. (1997). "Space Habitats". The Ultimate Encyclopedia of Science Fiction: The Definitive Illustrated Guide. Carlton. p. 50. ISBN   978-1-85868-385-0.
  28. Stableford, Brian (1999). "Fritz Leiber". In Bleiler, Richard (ed.). Science Fiction Writers: Critical Studies of the Major Authors from the Early Nineteenth Century to the Present Day (2nd ed.). New York: Charles Scribner's Sons. p. 441. ISBN   0-684-80593-6. OCLC   40460120.
  29. Hadhazy, Adam (October 30, 2020). "Could We Build a Dyson Sphere?". Popular Mechanics . Archived from the original on March 10, 2021. Retrieved March 20, 2024.
  30. Howell, Elizabeth (March 12, 2020). "'Dyson sphere' legacy: Freeman Dyson's wild alien megastructure idea will live forever". Space.com . Retrieved March 20, 2024.
  31. Nemecek, Larry (2003). Star Trek: The Next Generation Companion (3rd ed.). Pocket Books. pp. 218–220.
  32. Wright, Robert (2011). "MeaningofLife.tv". slate.com. Slate. Archived from the original on 20 August 2011. Retrieved 20 March 2024. Wright: Did they actually use the phrase 'Dyson sphere' on Star Trek?
    Freeman Dyson: Oh yes.
    Wright: Did they really?
    Freeman Dyson: One of my daughters sent me a tape of that program afterwards and so I watched it. Oh yes, it's very clearly labeled and actually it was sort of fun to watch it, but it's all nonsense. But it's quite a good piece of cinema. [punctuation supplied for unedited transcript]
  33. 1 2 Ayers, Jeff (2006). Voyages of Imagination: The Star Trek Fiction Companion. Simon and Schuster. ISBN   9781416525486.
  34. Nicholls, Peter (1983). "Far-future energy". In Nicholls, Peter (ed.). The Science in Science Fiction . New York: Knopf. pp. 44–45. ISBN   0-394-53010-1. OCLC   8689657.
  35. Mann, George (2001). "Dyson Sphere". The Mammoth Encyclopedia of Science Fiction. New York: Carroll & Graf Publishers. p. 477. ISBN   978-0-7867-0887-1.

Further reading