The intelligence in ETI—What can we know?

This paper follows a train of thought initiated in a recent paper [7]. The work sets out a theoretical perspective on the possibility of cognitive universals underpinning the behaviour of animals with brains. Consideration of what we can know of intelligence in beings elsewhere in the universe obliges us to recognise universal and local factors relevant to SETI. Linguistic communication turns out to be genuinely constrained by circumstances even though the existence of linguistic activity will be universal in intelligent beings. The implications for activity in SETI are reviewed. An alternative approach to SETI—described in a recent paper ([9], but see also [8]) is contrasted with the messaging approach, and the conclusion is drawn that an ETI would opt for the alternative.     

SETI in the light of cosmic convergent evolution

Theodosius Dobzhansky, one of the founding fathers of the modern evolutionary synthesis, once famously stated that “nothing makes sense in biology except in the light of evolution”. Here it will be argued that nothing in astrobiology makes sense except in the light of “Cosmic Convergent Evolution” (CCE). This view of life contends that natural selection is a universal force of nature that leads to the emergence of similarly adapted life forms in analogous planetary biospheres. Although SETI historically preceded the rise of astrobiology that we have witnessed in the recent decade, one of its main tenets from the beginning was the convergence of life on a cosmic scale toward intelligent behavior and subsequent communication via technological means. The question of cultural convergence in terms of symbolic exchange, language and scientific capabilities between advanced interstellar civilizations has been the subject of ongoing debate. However, at the core of the search for extraterrestrial intelligence lies in essence a biological problem since even post-biological extraterrestrial intelligences must have had an origin based on self-replicating biopolymers. Thus, SETI assumes a propensity of the Universe towards biogenesis in accordance with CCE, a new evolutionary concept which posits the multiple emergence of life across the Cosmos. Consequently, we have to wonder about the biophilic properties the Universe apparently exhibits, as well as to try to find an encompassing theory that is able to explain this “fine-tuning” in naturalistic terms. The aims of this paper are as follows: 1) to emphasize the importance of convergent evolution in astrobiology and ongoing SETI research; 2) to introduce novel and biology-centered cosmological ideas such as the “Selfish Biocosm Hypothesis” and the “Evo Devo Universe” as valuable arguments in theorizing about the origin and nature of extraterrestrial intelligence and 3) to synthesize these findings within an emerging post-biological paradigm on which future SETI efforts may be founded.     

Asymmetry in Active SETI: A case for transmissions from Earth

The Search for Extraterrestrial Intelligence (SETI) typically presupposes contact with extraterrestrial civilizations much longer lived than humanity. Many have argued that given humanity's “youth,” the burden of transmitting should be placed on the extraterrestrial civilizations, which presumably possess more advanced technologies. These assumptions have contributed to the current emphasis on Passive SETI. Complementing this existing stress on Passive SETI with an additional commitment to Active SETI, in which humankind transmits messages to other civilizations, would have several advantages, including (1) addressing the reality that regardless of whether older civilizations should be transmitting, they may not be transmitting; (2) placing the burden of decoding and interpreting messages on advanced extraterrestrials, which may facilitate mutual comprehension; and (3) signaling a move toward an intergenerational model of science with a long-term vision for benefiting other civilizations as well as future generations of humans. Technological requirements for Active SETI are considered, and a case is made for Active SETI as a means for experimentally testing variants of the Zoo Hypothesis. Recommendations are provided for sustaining Passive and Active SETI and the communities that conduct these searches.     

Terrestrial biological evolution and its implication for SETI

A frequent opinion among biologists upholds that biological evolution is contingent and, consequently, that man's apparition is a random event of very small probability. We present various arguments against this view, based on chemistry, molecular biology, evolutionary convergences, the existence of physical constraints on the structure of living beings, and the evidence of acceleration in the evolution of many features, e.g. brain size, over geological times. Taken together they suggest that “laws” of evolution exist and may have a universal validity. We extend this view to the evolution of “intelligence”. We show that it is an essential aspect of biological evolution and that human cultural evolution is just another aspect of it. Finally, we argue that brains more complex than the human brain are conceivable, endowed not merely with quantitatively better functions but with qualitatively higher cognitive abilities, of the kind found in the transition from, say, dog to man. This thesis predicts that the usual concept of advanced civilizations merely separated by huge distances is too restrictive. It favours a different concept, in which the separation results predominantly from cognitive, i.e. temporal factors. This idea, far from being discouraging, offers a stimulating solution to Fermi's paradox and opens new ways to SETI.     

SETI meets a social intelligence: Dolphins as a model for real-time interaction and communication with a sentient species

In the past SETI has focused on the reception and deciphering of radio signals from potential remote civilizations. It is conceivable that real-time contact and interaction with a social intelligence may occur in the future. A serious look at the development of relationship, and deciphering of communication signals within and between a non-terrestrial, non-primate sentient species is relevant. Since 1985 a resident community of free-ranging Atlantic spotted dolphins has been observed regularly in the Bahamas. Life history, relationships, regular interspecific interactions with bottlenose dolphins, and multi-modal underwater communication signals have been documented. Dolphins display social communication signals modified for water, their body types, and sensory systems. Like anthropologists, human researchers engage in benign observation in the water and interact with these dolphins to develop rapport and trust. Many individual dolphins have been known for over 20 years. Learning the culturally appropriate etiquette has been important in the relationship with this alien society. To engage humans in interaction the dolphins often initiate spontaneous displays, mimicry, imitation, and synchrony. These elements may be emergent/universal features of one intelligent species contacting another for the intention of initiating interaction. This should be a consideration for real-time contact and interaction for future SETI work.     

The benefits and harm of transmitting into space

Deliberate and unintentional radio transmissions from Earth propagate into space. These transmissions could be detected by extraterrestrial watchers over interstellar distances. This article analyzes the harm and benefits of deliberate and unintentional transmissions relevant to Earth and humanity. Comparing the magnitude of deliberate radio broadcasts intended for messaging to extraterrestrial intelligence (METI) with the background radio spectrum of Earth, we find that METI attempts to date have much lower detectability than emissions from current radio communication technologies on Earth. METI broadcasts are usually transient and several orders of magnitude less powerful than other terrestrial sources, such as astronomical and military radars, which provide the strongest detectable signals. The benefits of radio communication on Earth most probably outweigh the potential harm of detection by extraterrestrial watchers; however, the uncertainty regarding the outcome of contact with extraterrestrial beings creates difficulty in assessing whether or not to engage in long-term and large-scale METI.     

A protocol for messaging to extraterrestrial intelligence

Messaging to extraterrestrial intelligence (METI) is a branch of study concerned with constructing and broadcasting a message toward habitable planets. Since the Arecibo message of 1974, the handful of METI broadcasts have increased in content and complexity, but the lack of an established protocol has produced unorganized or cryptic messages that could be difficult to interpret. Here we outline the development of a self-consistent protocol for messaging to extraterrestrial intelligence that provides constraints and guidelines for the construction of a message in order to maximize the probability that the message effectively communicates. A METI protocol considers several factors, including signal encoding, message length, information content, anthropocentrism, transmission method, and transmission periodicity. Once developed, the protocol will be released for testing on different human groups worldwide and across cultural boundaries. An effective message to extraterrestrials should at least be understandable by humans; releasing the protocol for testing will allow us to improve the protocol and develop potential messages. Through an interactive website, users across the world will be able to create and exchange messages that follow the protocol in order to discover the types of message better suited to cross-cultural communication. The development of a METI protocol will serve to improve the quality of messages to extraterrestrials, foster international collaboration, and extend astrobiology outreach to the public.     

Toward understanding the active SETI debate: Insights from risk communication and perception

Insights from the robust field of risk communication and perception have to date been almost totally absent from the policy debate regarding the relative risks and merits of Active SETI or Messaging to Extraterrestrial Intelligence (METI). For many years, the practice (or proposed practice) of Active SETI has generated a vigorous and sometimes heated policy debate within the scientific community. There have also been some negative reactions in the media toward the activities of those engaged in Active SETI. Risk communication is a scientific approach to communication regarding situations involving potentially sensitive or controversial situations in which there may be high public concern and low public trust. The discipline has found wide acceptance and utility in fields such as public health, industrial regulation and environmental protection. Insights from the scientific field of risk communication (such as omission bias, loss aversion, the availability heuristic, probability neglect, and the general human preference for voluntary over involuntary risks) may help those who have participated in either side of the debate over Active SETI to better understand why the debate has taken on this posture. Principles of risk communication and risk perception may also help those engaged in Active SETI to communicate more effectively with other scientists, the public, with the media, and with policy makers regarding their activities and to better understand and respond to concerns expressed regarding the activity.     

Positive consequences of SETI before detection

Even before a signal is detected, six positive consequences will result from the scientific search for extraterrestrial intelligence, usually called SETI. (1) Humanity’s self-image: SETI has enlarged our view of ourselves and enhanced our sense of meaning. Increasingly, we feel a kinship with the civilizations whose signals we are trying to detect. (2) A fresh perspective: SETI forces us to think about how extraterrestrials might perceive us. This gives us a fresh perspective on our society’s values, priorities, laws and foibles. (3) Questions: SETI is stimulating thought and discussion about several fundamental questions. (4) Education: some broad-gage educational programs have already been centered around SETI. (5) Tangible spin-offs: in addition to providing jobs for some people, SETI provides various spin-offs, such as search methods, computer software, data, and international scientific cooperation. (6) Future scenarios: SETI will increasingly stimulate us to think carefully about possible detection scenarios and their consequences, about our reply, and generally about the role of extraterrestrial communication in our long-term future. Such thinking leads, in turn, to fresh perspectives on the SETI enterprise itself.     

Responsibility,capability, and Active SETI: Policy,law, ethics,and communication with extraterrestrial intelligence

With recently growing interest in the Active Search for Extraterrestrial Intelligence (SETI), in which humankind would send intentional signals to extraterrestrial civilizations, there have been increased concerns about appropriate policy, as well as the role of space law and ethics in guiding such activities. Implicit in these discussions are notions of responsibility and capability that affect judgments about whether humans or other civilizations should initiate transmissions. Existing protocols that guide SETI research address transmissions from Earth, but there is debate over whether these guidelines should inform de novo transmissions as well. Relevant responsibilities to address include (1) looking out for the interests of humankind as a whole, (2) being truthful in interstellar messages, and (3) benefiting extraterrestrial civilizations. Our capabilities as a species and a civilization affect how well we can fulfill responsibilities, as seen when we consider whether we will be able to reach consensus about message contents (and whether that would be desirable), and whether we have the capacity to decode messages from beings that rely on different sensory modalities. The interplay of these responsibilities and capabilities suggests that humankind should place increased emphasis on Active SETI.     

An international relations perspective on the consequences of SETI

Can we envision what the laws of politics and the laws of ethics will be in extraterrestrial civilizations? The laws of physics and chemistry will be the same. Presumably, if there are biospheres in other solar systems, the nature of biology will be the same. Over time evolution may produce the same forms of consciousness and intelligence as we see on earth. However, the political and ethical systems on earth are diverse. Often our images of extraterrestrial civilizations are mere projections of earthly patterns of conflict and cooperation. Perhaps over time the many civilizations and patterns on earth will evolve into one global civilization with harmonious political and ethical norms. These may be the same in universal civilizations if evolution is a cosmic process.     

Mass-, time-, and energy-characteristics of the interstellar flights during the long proper time of astronauts

The existence of extraterrestrial intelligence (ETI) and extraterrestrial scientific-technical civilization (STC) is of principal importance for CETI (communication with extraterrestrial intelligence) and SETI (search for extraterrestrial intelligence). According to Kardashev and Bracewell, the Earth-like STC in their farther development can expand to the nearby planetary systems of the Galaxy, creating galactic community (Bracewell's galactic club).In a previous paper the possibilities of the one-step relativistic rocket interstellar flight during the proper time of life of one-two generations of astronauts were analysed. The realization of such interstellar flights is very improbable, even to the nearest stars. These results could be true for the case of the comparatively short proper time of astronauts, i.e. large acceleration. But flights to the nearest stars could be realized with small and very small accelerations. In the present paper are calculated the proper times t in the reference systems connected with the astronauts (S₂), as well as the times T in the reference systems (S₁)-inertial, velocities v in S₁, mass ratios, powers and energies for various flights, exhaust velocities u and accelerations a. Results are critically discussed.     

Nonconscious intelligence in the universe

Animals lacking humanoid intelligence have evolved systems indistinguishable in function, if not in structure, from systems built by humans. Although radio communication has never been verified in animals, it is completely feasible biologically. If such systems are present in non-intelligent organisms on other planets, then our chances of detecting life in the universe by current SETI methods are greatly enhanced.     

Project Phoenix and beyond. Pesek Lecture

Although there are no federally funded projects at this time, SETI (the search for extraterrestrial intelligence) is a vigorous exploratory science. There are currently eight observational programs on telescopes around the world, of which the Phoenix Project is the most comprehensive. Most of these projects are rooted in the conclusions of the pioneering studies of the early 1970's that are summarized in the Cyclops Report. Technology has experienced an exponential growth over the past two and a half decades. It is reasonable to reassess the Cyclops conclusions as SETI enters the next century. Listening for radio signals is still the preferred method of searching, however new technologies are making searches at other wavelengths possible and are modifying the ways in which the radio searches can and should be conducted. It may be economically feasible to undertake the construction of very large telescopes that can simultaneously provide multiple beams on the sky for use by SETI and the radioastronomy community.     

Ten thousand revolutions: conjectures about civilizations

Ten thousand years ago, no-one on Earth was living a “civilized” life. What has happened since is remarkable and impossible to fully comprehend; yet, everyone has ideas about civilization, and how the world came to be as it is. Such understandings of civilizations on Earth inevitably influence speculation about extraterrestrial civilizations, in two ways. First, sometimes a specific Earth civilization or historical experience is explicitly used as a basis for inferences about extraterrestrial civilizations. Second, more general assumptions about the development and functioning of Earth's societies shape conjectures about alien societies. This paper focuses on the latter, general assumptions, with the aim of considering how we can use multidisciplinary approaches, and our knowledge of Earth's civilizations, to our best advantage in SETI.     

A SETI metapolicy: New directions towards comprehensive policies concerning the detection of extraterrestrial intelligence

At present we have only one agreed public policy for handling the detection of an extraterrestrial intelligence (ETI), the ‘First SETI Protocol’ of 1989, which guides action in the immediate aftermath of detection, even though SETI (the Search for Extraterrestrial Intelligence) constitutes an active search for such a detection. The purpose of this paper is to set out areas in which policies might fruitfully be developed, including reviewing the rationale and investment in SETI, handling ETI artefacts, and approaches to direct contact. ‘Negative’ possibilities will be examined, for example, whether an ETI artefact or data should be purposefully destroyed.     

Reply policy and signal type: assumptions drawn from minimal source information

A scenario is developed under which a discovery of extraterrestrial technology is made by one of the World’s search for exterrestial intelligence (SETI) programs. The nature of the signal received gives an absolute minimum of information as to the nature of the senders. Current SETI detection and reply policy is examined under these assumptions. Current policy calls for prompt and public release of signal information and stellar coordinates upon announcement of a discovery. The SETI protocol calls for no reply until authorized by international consultations. It is argued that changes are needed in these policies to guard against the possibility of unauthorized replies that could severely complicate long-term interstellar communication.     

Efficiency in SETI

While modern SETI experiments are often highly sensitive, reaching detection limits of 10^?25 W/m² Hz in the radio, interstellar distances imply that if extraterrestrial societies are using isotropic or broad-beamed transmitters, the power requirements for their emissions are enormous. Indeed, isotropic transmissions to the entire Galaxy, sufficiently intense to be detectable by our current searches, would consume power comparable to the stellar insolation of an Earth-size planet.In this paper we consider how knowledge can be traded for power, and how, and to what degree, astronomical accuracy can reduce the energy costs of a comprehensive transmission program by putative extraterrestrials. Indeed, an exploration of how far this trade-off might be taken suggests that extraterrestrial transmitting strategies of civilizations only modestly more advanced than our own would be, as are our SETI receiving experiments, inexpensive enough to allow multiple efforts. We explore the consequences this supposition has for our SETI listening experiments.     

The art and science of interstellar message composition: a report on international workshops to encourage multidisciplinary discussion

Throughout the history of the Search for Extraterrestrial Intelligence (SETI), there has been widespread recognition of the profound societal implications of detecting intelligence beyond Earth. At the SETI Institute, interstellar message construction serves as the focus of a multidisciplinary attempt to prepare for the cultural impact of signal detection and the critical events that would follow. Interstellar message construction at the SETI Institute builds upon the recommendations of the 1991–1992 Workshops on the Cultural Aspects of SETI, while also exploring opportunities for multidisciplinary contributions on new topics. Through a series of international workshops in Toulouse, Paris, Zagreb, Washington, and Bremen, the SETI Institute and partner organizations have fostered broad-based discussion about some of the most important decisions that would follow detection of extraterrestrial intelligence, including “should we reply?” and if so, “what should we say, and how might we say it?”. Several of the themes addressed at these workshops will be highlighted, including the relationship between art and science in designing messages, the value of interactive messages, and the importance of better understanding the nature of language.     

Is interstellar archeology possible?

Searching for signatures of cosmic-scale archeological artifacts such as Dyson spheres is an interesting alternative to conventional radio SETI. Uncovering such an artifact does not require the intentional transmission of a signal on the part of the original civilization. This type of search is called interstellar archeology or sometimes cosmic archeology. A variety of interstellar archeology signatures is discussed including non-natural planetary atmospheric constituents, stellar doping, Dyson spheres, as well as signatures of stellar, and galactic-scale engineering. The concept of a Fermi bubble due to interstellar migration is reviewed in the discussion of galactic signatures. These potential interstellar archeological signatures are classified using the Kardashev scale. A modified Drake equation is introduced. With few exceptions interstellar archeological signatures are clouded and beyond current technological capabilities. However SETI for so-called cultural transmissions and planetary atmosphere signatures are within reach.