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SETI IS HAMPERED BY PAROCHIAL VIEWS LIMITED BY THE POLITICS AND ECONOMICS OF THE DAY-Davies ‘10
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- SETI HAS NO OBVIOUS PLACE TO LOOK AND NO CLEAR ROUTE TO DISCOVERY-Shostak ‘01
- THERE IS NO REASON TO BELIEVE THAT ALIENS WOULD APPRECIATE DIFFERENCES IN OUR TECHNOLOGY AND MIGHT NOT USE RADIO-Davies ‘10
- LISTENING IN ON EXTRATERRESTRIALS AS IF THEY ARE USING RADIO IS A HARD SELL-Davies ‘10
- THE CENTRAL DOGMA OF SETI, THAT RADIO WAVES ARE BEING TRANSMITTED TO US, IS NOT CREDIBLE-Davies ‘10
- EXISTING SETI SYSTEMS CANNOT DEAL WITH PULSES, A MORE LIKELY MEANS OF TRANSMISSION-Davies ‘10
SETI IS HAMPERED BY PAROCHIAL VIEWS LIMITED BY THE POLITICS AND ECONOMICS OF THE DAY-Davies ‘10 [Paul; PhD; co-Director of the Cosmology Initiative, both at Arizona State University; The Eerie Silence: Renewing Our Search for Alien Intelligence; 2010; Kindle Edition] A greater degree of parochialism occurs when SETI gets influenced by human politics and even economics. One of the main unknowns is the longevity of a communicating civilization. The challenge is to guess whether ET will be on the air for centuries, millennia or even longer. During the Cold War, many SETI proponents reasoned that the development of advanced radio communication would be paralleled by similar-level technological developments, such as nuclear weapons. Because our own society was at that time in grave danger of nuclear annihilation, it was fashionable to argue that alien technological civilizations likewise wouldn't last long. They would have their own Cold War which, after a few decades, would turn hot, and knock them off the air. When the (terrestrial) Cold War ended, human political concerns shifted to the environment, and SETI thinking duly shifted with it. The hot-button issue now, in many people's eyes, is no longer nuclear war, but sustainability. Transmitting powerful radio waves across the galaxy would require large-scale engineering and soak up a lot of energy. Surely an advanced alien civilization would tailor its technology so as to minimize the environmental impact? Well, maybe. But that line of reasoning would have been received sceptically in the 1960s political atmosphere, and may well be regarded as irrelevant in another hundred years, when environmental problems may be replaced by other concerns. There is no reason to suppose that a million-year-old super-civilization would have 'a sustainability problem'. It might, of course, have some other problem, maybe one we couldn't anticipate, or wouldn't understand even if we were told. SETI is the quintessentially long-term project, and it is foolish to base too much of our search strategy on flavour-of-the-month political fashion. Guessing the political priorities of an alien civilization is futile. SETI HAS NO OBVIOUS PLACE TO LOOK AND NO CLEAR ROUTE TO DISCOVERY-Shostak ‘01 [Seth; The Future of SETI; Sky & Telescope; April 2001; http://www.skyandtelescope.com/resources/seti/3304566.html; retrieved 22 Jul 2011] Planets inhabited by high technologies (if they exist at all) are surely much rarer than planets inhabited by bacteria. After all, microbes were Earth's most advanced life forms for nearly a million times longer than the span of written human history. But a tantalizing prospect fires the imagination: the rare technological worlds may actually be the easiest to find. Unlike bacteria, intelligent creatures could make themselves known across vast interstellar distances. They could do it with radio transmitters or lasers not much bigger than our own. Maybe they are doing it right now. Searches for extraterrestrial intelligence (abbreviated SETI) have no obvious hunting ground and no clear route to discovery. Instead, after 40 years researchers have amassed a mountain of speculation and only a small hill of experiment. If sentient beings exist among the stars, they have remained beyond the grasp of our instruments. THERE IS NO REASON TO BELIEVE THAT ALIENS WOULD APPRECIATE DIFFERENCES IN OUR TECHNOLOGY AND MIGHT NOT USE RADIO-Davies ‘10 [Paul; PhD; co-Director of the Cosmology Initiative, both at Arizona State University; The Eerie Silence: Renewing Our Search for Alien Intelligence; 2010; Kindle Edition] My point is that modest advances in human technology have led within just a few decades to a change in thinking about likely alien communication frequencies. There is a major lesson in this example. It is wise to view the situation through the eyes of the civilization setting out to communicate with us, on the assumption that it has been around for a very long time – at least one million years, and maybe 100 million years or more. Although the aliens may well settle on radio as the medium (perhaps for our benefit), they can hardly be expected to discriminate between 1950s and 1980s levels of human technology. LISTENING IN ON EXTRATERRESTRIALS AS IF THEY ARE USING RADIO IS A HARD SELL-Davies ‘10 [Paul; PhD; co-Director of the Cosmology Initiative, both at Arizona State University; The Eerie Silence: Renewing Our Search for Alien Intelligence; 2010; Kindle Edition] If ET is monitoring our radio traffic, it will seem to have risen to a peak in the late twentieth century and then begun to fade. In another hundred years, there may be no substantial radio output from Earth. (Radar might still be used, plus the occasional command to a space probe.) So unless an alien community has a deliberate policy of transmitting powerful radio signals, it is entirely possible that the galaxy is bustling with advanced civilizations yet has no detectable artificial radio signature. It has been estimated that if we built a radio telescope 100 kilometres (60 miles) in diameter, it would be so sensitive we could detect a TV station as far away as Sirius, so it wouldn't matter whether ET were beaming messages directly at us or not. But if Sirius TV is delivered via cable, we'd be out of luck. Eavesdropping on an extraterrestrial civilization on the premise that the aliens may still be using 1980s human technology is a hard sell. THE CENTRAL DOGMA OF SETI, THAT RADIO WAVES ARE BEING TRANSMITTED TO US, IS NOT CREDIBLE-Davies ‘10 [Paul; PhD; co-Director of the Cosmology Initiative, both at Arizona State University; The Eerie Silence: Renewing Our Search for Alien Intelligence; 2010; Kindle Edition] The traditional approach to SETI is based on the belief that alien civilizations are targeting Earth with narrow-band radio messages. But in my opinion, this 'central dogma' simply isn't credible. The reason concerns the finite speed of light, and the fact that no signal or physical effect can propagate any faster. This absolute speed limit is a fundamental law of physics having to do with the nature of space and time. Unless our understanding of basic physics is badly wrong (in which case, much of the discussion about SETI is moot), we have to live with the restriction. To appreciate the implications, consider an alien civilization situated 1,000 light years away – close even by the standards of SETI optimists – and suppose that the aliens possess technology so powerful that they can observe the Earth in detail. What will they see? Well, they won't see us. They won't see our radio telescopes or our particle accelerators or roads or rockets. What they will see is Earth c. AD 1010. That date is well before the Industrial Revolution, at a time when the pinnacle of human technology was the clockwork. The aliens might see the Egyptian pyramids and the Great Wall of China. They would notice cities and signs of agriculture, but that is a far cry from interstellar telecommunication technology. The fact that humans had developed the use of building and agriculture might be promising, but it would certainly not guarantee the appearance of radio telescopes 1,000 years later (as opposed to, say, 5,000 or 50,000 years later). Therefore, there would be no reason for the aliens to begin transmitting radio signals our way in AD 1010. Better for them to wait until they know we actually have the means to receive the signals before going to the trouble of sending them. EXISTING SETI SYSTEMS CANNOT DEAL WITH PULSES, A MORE LIKELY MEANS OF TRANSMISSION-Davies ‘10 [Paul; PhD; co-Director of the Cosmology Initiative, both at Arizona State University; The Eerie Silence: Renewing Our Search for Alien Intelligence; 2010; Kindle Edition] The challenge for SETI is to discriminate between an artificial pulse and a natural one. If an alien civilization wanted to use pulses to attract attention, it would need to tag them with a signature of intelligence, such as a simultaneous transmission centred on several radio channels at frequencies that bear a noticeable arithmetic pattern. Existing SETI systems are not well adapted to dealing with such signals, because both the hardware and data analysis are mainly designed for continuous narrow-band sources. But there is no fundamental obstacle to conducting a search for pulses; the issue boils down to resources. Looking for transient events requires monitoring a slice of sky continuously for some time – say one year – because even if we can make an intelligent guess where in the sky the beacon might be located we don't know when it will next bleep. 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