SMBH and super extraterrestrial civilizations（the web version）

Dr Makoto Inoue published a hypothesis last year to discuss how SMBH can be utilized as an

energy source by Type III civilizations of Kardashev classification, if there indeed is one. This

hypothesis of Inoue is his private kick, and an interesting and pioneer one, to try based on

scientific logic to expand the limit of SMBH imagination.

Hypotheses normally draw different faces of responses and feedbacks, some people may feel

interesting, incredible, some say ok and some disagree. But Inoue is not bothered, since after all

the challenges, hypothesis may be declined, yet some be proved and become theories. It is these

repeatedly logical challenges and discussion that push science forward, isn’t it?

Before introducing this hypothesis, let’s have a look first at what Type III civilization is.

【Kardashev classification of advanced civilizations】

Physicists, when they say to search extraterrestrial intelligence, they are not to find“little green

man” or “ET”, but to search Type I, II and III advanced civilizations of Kardashev

classification. But what are these?

Russian astronomer Nikolai Kardashev was the first to propose this index. He classified

extraterrestrial civilizations into three types according to energy that is required and can be

managed to sustain and advance the technology level of the civilization. In 1963 Kardashev

examined quasar CTA-102, the first Soviet effort in the search for extraterrestrial intelligence

(SETI). In this work he came up with the idea of galactic civilizations that may be millions or

billions of years ahead of us; energy released from highly radioactive objects in the universe can

be perfect sources of momentum to sustain these civilizations. In the following year, Kardashev

classification was proposed. Since then, this theory was adopted as theoretic basis by many

science fiction novels, movies and animations, by prophets, and by SETI. Famous pieces include

Stargate, Star trek, Orbitsvilleo, Ringworld, Battlestar Galactica, Star Wars, Men in Black, Dr

Who, New X-Men, Space Battleship Yamato（宇宙戰艦大和號）, Legend of the Galactic Heroes

（銀河英雄傳說）, Crest of the Stars（星界的紋章）, etc.

Type I of Kardashev classification with energy consumption at 4x1019

erg/sec (i.e. 4x1012

watts)

has a technological level that can utilize successfully all energy sources an entire colonial planet

can provide. Taking earth as an example, the civilization must be able to manage energy deep

under the earth and the sea, and be able to control earthquake, typhoons, tornados, and tsunamis.

Type II with energy consumption at 4x1033

erg/sec (4x1026

watts) is a civilization capable of

harnessing all energy radiated by its own star. To achieve this, a Dyson sphere or the similar

surrounding the mother star is built, which is a huge power plant web to collect, transmit and

convert radiated energy. This concept was proposed by Freeman Dyson. Type II has reached to

the level capable of managing roughly a scale of a solar system. According to Physicist Michio

Kaku, Type II is a very stable civilization hardly to be collapsed.

Type III as the most advanced civilization can control energy on a galactic scale, which can

possibly contain thousand of millions of star systems. The energy consumption level is at

4x1044

erg/sec (4x1037

watts), about the scale our milky way is possessed. Type III can adopt

similar technology and system that Type II has to collect radiations from stars in the galactic

system; they may even utilize energy from SMBH that is often found at the center of many

galaxies. Space-time travel is believed to be a common way of commuting within such

civilizations.

There are scholars proposed that civilization on earth of our present one is leveled somewhere

between Type 0 and Type I. By calculation, famous scholar of SETI, Carl Sagan suggested that

earth of 1973 would represent a Type 0.7 civilization in this classification. Michio Kaku

predicted human civilization may upgrade to Type I in coming one or two hundreds of years. But

the transition from Type 0 to Type I is not an easy one, it in fact is highly risky, we can either

make it or ruin it. The reason is, in order to achieve this upgrade, mankind need to be able to

exploit every possible energy resource on earth, but they may not be capable of evacuating the

enormous waste heat and garbage produced from the overuse of resources. This can end up with

an unwanted result turning earth to an unlivable planet. We can only wish science of future able

to overcome these dilemmas. Perhaps we should consider to land mankind to other planets first

before the day comes, or to dump waste heat to outer space in solar system so to make sure the

success of the upgrade.

Although based on mathematic calculation, it is said there should be at least a thousand of Type I

to III Kardashev civilizations, yet none is observed or detected.

【SMBH and super extraterrestrial civilizations】

Inoue’s hypothesis has nothing to do with current earth civilization. It is to discuss how SMBH

can be managed as an energy source by Type III civilizations of Kardashev classification.

There are two key assumptions in Inoue’s hypothesis. That is, Type III of Kardashev scale is

not an “isolated”civilization, but a galactic club formed by many civilization members of a

kind in a galaxy, like what we see in the film Star Trek. The energy source of a galactic club is

the SMBH at the center of the galaxy. Habitants in a galactic club are not necessarily living

nearby the dangerous SMBH to utilize its energy. Alternatively, power grid system can be

developed to collect and to deliver energy to club members. In the power network, there are

power collectors near central SMBH doing energy generation and disposition, mid-way power

plants to transmit energy to different habitat solar systems, and local power stations to convert

and distribute energy to club members. The system could even be remotely controlled by

individual intelligent habitat. But the design of the power network will be different from Dyson

sphere of Type II civilization. The “sphere” has to be broken into “Dyson shells” to keep

some area uncovered to give way to emanating jets and accreting flows around SMBH.

Energy transmitted by Dyson shells and such to the habitat should be accomplished presumably

by electro-magnetic radiation. The transmission efficiency is primarily important and therefore

selection of the wavelength region becomes the key. Take the example of Sgr A*, the SMBH in

our Galactic Center, near infrared is possibly the best efficient wavelength choice. This suggests

when we choose the transmission frequency; some points need to be taken into account,

including the spectral energy distribution of the radiation from the accretion disk, the energy

conversion efficiency of the power plant for the transmission, and the transmission efficiency

through the interstellar medium of the galaxy. Inoue had detailed discussion of various accounts

in his thesis. Energy transmitted by a sharp beam of coherent electro-magnetic waves from

SMBH may provide a new clue for SETI for the detection of energy transmission signals. This

may also help expand their search window for other intelligences in the Universe.

Inoue emphasizes this hypothesis is not rootless imagination like time travel and such. To

propose this hypothesis is to explore possibility and limit of some scientific thinking based on

known science and technology, and so to ground a foundation for further exploration or future

development. The truth is, up to now there are some scientific academic support to the theories

or hypotheses on such energy consumption, collection and transmission of extraterrestrial

civilizations. Then of course we would also like to learn what possible energy sources are out

there in the space to be utilized. Stars and black holes thus become our targets of exploration.

However, if there is indeed an efficient usage of SMBH energy by advanced Type III, we will

need to emphasize more careful discrimination to the radiation beams detected surrounding

SMBH. They can be emanations from jet or accretion flows, but there is also the possibility that

the emissions are from the power grid system. It is expected that many unknowns will be there

awaiting us to seek further. For example, in what form the SMBH energy can be transmitted

from collectors to civilizations, radio, optical, or infrared? And, where would be the proper sites

to place those power plants, in other words, where can be the orbits of the power plants in the

galaxy?

Inoue’s hypothesis is so far a scientific assumption; there is yet no related observation or

research to demonstrate this proposal of energy transmission system. Whether this hypothesis

will become a theory, perhaps science of future will have a say. (Plain draft by Joyce Chen,

Reviewed by Dr Makoto Inoue)

Makoto Inoue and Hiromitsu Yokoo, Type III Dyson Sphere of Highly Advanced Civilisations

around a Super Massive Black Hole, JBIS Vol. 64, pp.58-61, 2011

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