A Dyson Sphere around a black hole

Abstract

The search for extraterrestrial intelligence (SETI) has been conducted for nearly 60 years. A Dyson Sphere, a spherical structure that surrounds a star and transports its radiative energy outward as an energy source for an advanced civilisation, is one of the main targets of SETI. In this study, we discuss whether building a Dyson Sphere around a black hole is effective. We consider six energy sources: (i) the cosmic microwave background, (ii) the Hawking radiation, (iii) an accretion disk, (iv) Bondi accretion, (v) a corona, and (vi) relativistic jets. To develop future civilisations (for example, a Type II civilisation), $4\times 10^{26}\mathrm{W}$($1{\mathrm{L}}_{\odot }$) is expected to be needed. Among (iii) to (vi), the largest luminosity can be collected from an accretion disk, reaching $10^5{\mathrm{L}}_{\odot }$, enough to maintain a Type II civilisation. Moreover, if a Dyson Sphere collects not only the electromagnetic radiation but also other types of energy (e.g., kinetic energy) from the jets, the total collected energy would be approximately 5 times larger. Considering the emission from a Dyson Sphere, our results show that the Dyson Sphere around a stellar-mass black hole in the Milky Way ($10\mathrm{kpc}$ away from us) is detectable in the ultraviolet$(10-400\mathrm{nm})$, optical$(400-760\mathrm{nm})$, near-infrared($760\mathrm{nm}-5\mu \mathrm{m}$), and mid-infrared($5-40\mu \mathrm{m}$) wavelengths via the waste heat radiation using current telescopes such as Galaxy Evolution Explorer Ultraviolet Sky Surveys. Performing model fitting to observed spectral energy distributions and measuring the variability of radial velocity may help us to identify these possible artificial structures.

This paper has been accepted for publication in MNRAS

References in corpus (22)

• Advection-Dominated Accretion: A Self-Similar Solution
• Modelling the behaviour of accretion flows in X-ray binaries
• The Temperature of the Cosmic Microwave Background
• The Second Data Release of the Sloan Digital Sky Survey
• The Pan-STARRS1 Surveys
• A Measurement of the Electromagnetic Luminosity of a Kerr Black Hole
• Non-linear X-ray variability in X-ray binaries and active galaxies
• The power of relativistic jets is larger than the luminosity of their accretion disks
• Accretion onto the Supermassive Black Hole in M87
• The Dynamical Structure of Nonradiative Black Hole Accretion Flows
• Accretion onto the First Stellar Mass Black Holes
• On the interpretation of the multicolour disc model for black hole candidates
• Dyson Spheres
• Contribution of the accretion disk, hot corona, and obscuring torus to the luminosity of Seyfert galaxies: INTEGRAL and Spitzer observations
• A general relativistic model of accretion disks with coronae surrounding Kerr black holes
• The Habitable Epoch of the Early Universe
• A Complete Relativistic Ionized Accretion Disc in Cygnus X-1
• Preliminary Design of The Wide-Field Infrared Survey Explorer (WISE)
• Life under a black sun
• Searching for Exoplanets Around X-Ray Binaries with Accreting White Dwarfs, Neutron Stars, and Black Holes
• On the orbital and physical parameters of the HDE 226868/Cygnus X-1 binary system
• Far-infrared star-formation rates of six GRB host galaxies with ALMA

Cited by in corpus (10)

• Project Hephaistos - II. Dyson sphere candidates from Gaia DR3, 2MASS, and WISE
• Project Hephaistos I. Upper limits on partial Dyson spheres in the Milky Way
• General-relativistic thin-shell Dyson mega-spheres
• Avoiding the Great Filter: Predicting the Timeline for Humanity to Reach Kardashev Type I Civilization
• In Search of Extraterrestrial Artificial Intelligence Through Dyson Sphere-like structures around Primordial Black Holes
• SETI in 2021
• Search for Dyson rings around pulsars: unexpected light curves
• Ground to Dust: Collisional Cascades and the Fate of Kardashev II Megaswarms
• Microlensing Signatures of Dyson Sphere-like Structures around Primordial Black Holes as Technosignatures of Extraterrestrial Advanced Civilizations
• The Dyson Minds 2025 Workshop: SETI around Black Holes