Wednesday, 15 March 2017

Looking for Aliens: Day Two

The first talk on day two was given by science fiction writer Stephen Baxter, concerning his new novel, a sequel to H.G. Wells’ The War of the Worlds (1897). The sequel is entitled The Massacre of Mankind, and I was especially interested to hear this discussed because I’m a long time fan of Baxter’s work.

Baxter’s talk concerned the fictional Martians of Wells’ novel. In the original, these are described as intelligences ‘vast and cool and unsympathetic’ who ‘regarded this Earth with envious eyes’ and who ‘slowly and surely drew their plans against us.’ The original novel was one of the things that got me excited about SF in the first place, and it was evident that Stephen shared this enthusiasm.

The forms that Wells’ Martians took, giant heads with tentacles, were evolved from humanoid beings. In re-imagining them, Baxter had drawn on Wells’ speculations about our own, distant descendants and upon ideas then current of a dying Mars.

As he did this, Baxter came to feel some sympathy for the invaders, even seeing their positive virtues. He observed that humans shared their main flaw, which was a lack of empathy towards ‘lower’ creatures.

Stephen also delved into the cultural importance of fictional aliens, using the examples of Superman and Doctor Who. Fictional aliens can help us think about problems in SETI: for example, the Time Lord’s doctrine of non-intervention in Doctor Who could be seen as a form of the zoo hypothesis.

Next up was William Edmondson, who discussed his idea of finding a ET signal using pulsars as interstellar beacons. Pulsars are rapidly pulsing radio sources that are thought for be associated with a rotating neutron star. The regular pulses mean they can serve as cosmic lighthouses for any intelligence advanced enough to have radio telescopes.

William’s idea is that we could search for ET signals that are being sent from planets orbiting stars that are in alignment with a pulsar, from a terrestrial point of view.

He thinks that this would help to simplify the search for SETI in a targeted way, being skeptical of what he sees as some of the more outlandish ideas in SETI, such as searching for galaxy-spanning super-civilizations, or technology that’s indistinguishable from magic. Targeted SETI, by contrast, seems to him a more strategic and realistic

Edmondson is currently working with the Breakthrough Listen team, who have helped him get some observing time at the Parkes radio telescope in Australia. He’s also analysing older data gathered from the direction of six pulsars in M62, a globular star cluster in the constellation of Ophiuchus, about 22,500 light years distant. Although he hasn’t found a signal yet, it was intriguing to see this theory put to the test.

An especially stimulating talk was also given by Anders Sandberg, of the Future of Humanity Institute at Oxford University. Anders was looking at the infamous Fermi Paradox, named after the physicist Enrico Fermi who reputedly asked, if aliens exist then, given our assumptions about the universe, why aren’t they here? This paradox has fuelled much speculation in the past, a good spread of which can be found in Stephen Webb’s book Where Is Everybody? (2002).

Anders discussed the Drake Equation, which allows estimates of the number of possible communicating civilizations in the galaxy, and suggested that many past estimates suffered from being highly overoptimistic.

He gave a detailed theoretical analysis to show why we shouldn’t be especially surprised that we haven’t contacted anyone yet. At this stage in our knowledge, it’s a good bet that we don’t live in a Star Wars galaxy, brimming with intelligent aliens. In fact, the most plausible models of the origins of life and the rise of complex forms suggest that intelligence might be quite rare, even if microbial life is common. Quite rare, however, is very different from non-existent, so the search seems justified, given our state of knowledge. So Anders’ analysis implies that Fermi’s paradox was not so paradoxical, after all.

Afterwards, Ian Crawford touched on one more exotic solution to the Fermi paradox, which was that any technological aliens would have shed their biological bodies and uploaded themselves into virtual worlds on computers. This is known at the Singularity, and there is a running debate in future studies on its plausibility.

It’s relevant to the Fermi paradox because uploaded beings, the story goes, might not be interested in contact, preferring to stay cocooned in their presumably idyllic virtual worlds.

Crawford pointed out that, in the terrestrial case, those uploaded would probably be restricted to an elite, and that the bulk of people on Earth would remain as real, physical beings. Then, if our civilization collapsed, and nature is not completely wrecked, new intelligent beings might arise from the animals.

Although I found these arguments entertaining, they seemed to lack plausibility to me. I’m quite sceptical about singularity arguments, for reasons similar to Kim Stanley Robinson. I think that the idea we could simply upload our conscious minds into computers is the result of misreading what the neuroscience is telling us. In addition, I worry that by the time our civilization ends, that the ecosystems might have collapsed beyond the point of evolving a new dominant species in the foreseeable future.

Listening to these talks reminded me of the late philosopher of science John Ziman, and his ideas about reliable versus unreliable knowledge. Ziman pointed out that scientific knowledge remains far from complete, and is not uniformly certain.

The knowledge that the Earth goes around the sun, or that muscles work by sliding filaments, or that bacteria causes disease, can be called reliable because it is supported by mountains of evidence and accords well with the way we think the world works.

Many of the ideas floating about about SETI are not in this category. This is okay, because in frontier areas evidence will naturally be marginal or even non-existent. It is a mistake to suppose that scientists are omnipotent; they are more, as Paul Feyerabend once suggested, like ants crawling across the face of reality, working from the known to the unknown.

The ultimate goal of a science, Ziman claimed, ‘is a consensus of rational opinion over the widest possible field (Reliable Knowledge, 1978, p. 3).’ This is clearly not currently the case in SETI, where opinions over basic questions like the number of possible ETs still varies considerably, and there seems to be little agreement over search strategies.

However, like astrobiology, the field seems to me to be maturing, with a healthy injection of funding and by efforts to create links with mainstream astronomical work. I’d call SETI a premature science, which was Marcello Truzzi’s term for a discipline that is trying to ask questions for which we don’t, quite, have the capacity to answer yet.

Still, with all those telescopes listening, we might just get lucky….

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