Author: Shubham Kanodia

This article is based on pages 133 – 152 of Paul Davies `s book Eerie Silence. The extract builds upon the third law of Arthur C. Clarke, that “Any sufficiently advanced technology is indistinguishable from magic.” It discusses the principle for SETI artifact searches.

There are various structures / particles postulated by the fundamental theories of physics which have not been observed experimentally. Few of the examples cited in the passage are magnetic monopoles, dark matter particle and cosmic string. An example given is that the paucity of these could be due to exploitation of this structures / particles by a hyper – advanced ET civilization for energy production.

Moving on from here, the author builds on the ‘nature plus’ theme for ET. Basically how ET could manifest itself as the next step after nature and thus not stand out obviously like a sore thumb, but as an extension of the abilities and phenomenon seen naturally. He gives the example of a scenario from Roger Penrose about dumping waste into a black hole to harness its rotational kinetic energy.

Another important point made is that it is quite possible, perhaps even likely that ET manifests itself in a manner unfathomable to us. The example given is of lasers. For someone from a few centuries ago, lasers would not seem like a man – made thing and would seem like a weird (then inexplicable) naturally occurring phenomenon. On a similar note, potential ET technology could be right in our face but its artificial origins undetectable to us.

The last thing he covers is how the ‘laws of Physics’, which in theory are set in stone, are not really. They are only sacrosanct as far our current measurement capabilities are concerned. For example, ether was accepted till Michelson – Morley proved it otherwise. Newtonian gravity was good enough till observations began diverging from it and could no longer be explained by simple theory. Therefore the laws of Physics which we let govern us in our search for ET, might fundamentally be incomplete.

I think the point of this article is not to cast a gloomy note over our search for ET, but just to say that we do not know what we don’t know. Our knowledge and understanding of the ‘known’ Universe is severely lacking. Therefore, 1) we should not consider our search for ET exhaustive even if we plough through a major portion of the cosmic haystack unsuccessfully; 2) always be open to and on the watch for anomalies in observational data (similar to the point made in GHat 4).

In this post I shall discuss the white paper written by Jason Wright on the need for SETI to adopt standard terminology. The paper argues about the need for such an approach. In the era of advances in astrobiology, we need to find the right synergy between the two fields, and how SETI is rightfully a subset of astrobiology since it is also looking for signatures of life (biology) around celestial bodies.

The field of exoplanets has rapidly grown since the first discovery of an exoplanet around a star in 1995 [51 Pegasi b]. With advances in engineering and instrumentation we are slowly approaching the domain where we can detect the presence of an Earth like planet around a Sun like star in its habitable zone [Kasting 1991]. In tandem with this process of discovery,  the characterization of exoplanetary atmosphere and climate has also progressed using spectroscopy techniques; attempts have been made to detect biosignatures in these spectra of exoplanets.

Closer home, we also have ‘potentially’ habitable objects, which could  have harboured life in the past, or might have life in the present as well. Solar system bodies like Europa, Enceladus and Mars, are intriguing objects which might have the right conditions to sustain (or have sustained) life.

Astrobiology is generally touted to be limited to this search for biosignatures. However, as mentioned in the introduction, it must include not only biosignatures, but also technosignatures or signs of intelligent (advanced technologically) life.

A unified jargon is important in a diverse and interdisciplinary field like SETI which involves contributions and discourse from not only astronomers, but also engineers, anthropologists, linguists,  and potentially cryptologists. The paper by cites the example of Artifact SETI, and how it should be an umbrella term for various kinds of searches.

An example of this that I have encountered (a situation nowhere as close to as significant as  in SETI, however representative nonetheless), is when I tried to understand radio astronomer jargon in order to derive the relation between transmitter bandwidth and the sensitivity of a receiver. Being involved with optical and NIR astronomy, I am completely alien to radio astronomy. Despite both the fields being subsets of astronomy and governed by the same laws of Physics, there exist a large number of differences in how they measure and quantify similar parameters.  It would have been very useful if they used the same terminology or in the least had some kind of a guide to bridge the two.

Now, if we take this situation and extrapolate it to collaborations between the sciences and humanities, this problem gets severely exacerbated.  Hence, I think the framework adopted by this paper is necessary, and one that should be worked on as the field of SETI grows and involves collaborations from other fields and subjects.

This paper by Forgan et al. (2016) talks about the protocol that needs to be followed if  when we find extra terrestrial intelligence. To understand the need for this, one only needs to look at the commotion and media frenzy caused by Tabby’s star and Oumuamua.

The existence and search for ET has always been a favourite of popular media, simply because it catches the eye of the general public. It is a topic that attracts people from all age groups irrespective of their age group. The question of whether we are alone in the Universe is one of the fundamental questions that transcends Astronomy and science, and goes into philosophy and anthropology. It starts delving into the arena of religious beliefs and the anthropocentric view that biases us.

Considering the above, it is important to understand the importance of the search for ET. Any kind of media coverage of this topic is almost guaranteed to get good viewership / readership. Therefore any researcher associated with this field must tread very lightly and be cautious about any kinds of claims made or results published, which even REMOTELY can be interpreted to imply the existence or our successful detection of ET.  This does not mean that one must hide their research or not go public with it, for fear of rebuke. However, as the article discusses, there should be a framework that is followed before a search is conducted and transparency, once it is done and the data has been analyzed, and results obtained.

The article further lays forth a possible path to follow to release the data and clue in the media as to the results and the need for independent verification. Another step that the authors alluded to, is that an international consensus must be built. Currently the only body which has such a mandate is the United Nations. Within the United Nations, perhaps UNESCO? It could get interesting, albeit tricky if the UNESCO is tasked with building up an international opinion and charting a path forward. Namely because the United States of America has decided to withdraw from UNESCO as a member starting 2019.

Going by the past record and partisanship in the UN, it could be problematic for all the nations to reach a consensus. Since, any kind of interaction with an alien civilization could have far reaching consequences for all of humanity today and in the future, it is something that should definitely involve all the stakeholders, or at least their chosen representatives. We still divide the Earth with borders, however Space cannot be (at least not yet). Its contents and inhabitants (?) affect all of humanity. Could the answer be  Asgardia?

In this post I shall build upon some of the discussion from  Paul Davies (2013).  The article describes a search effort which uses data from the Lunar Reconnaissance Orbiter. They attempt to use data from this satellite with a resolution of about 50 cm/pixel, to find artifacts of ET on the Moon.

An important consideration in this search is the size of the data set that needs to be sifted through. The complete data set is expected to contain about a million frames of 500 Megabytes each, which translates to about 500 Terabytes in all. The search is for something left behind accidentally or on purpose by alien civilizations, a la  Transformers: Dark of the Moon (but mostly smaller?).

The challenge over here is that it is simply to numerous for a human or groups of humans to go over the entire data set manually, and the computer algorithms being used are not necessarily primed to look for signatures or anomalies highlighting the artificial origin. Another example of this is the Kepler mission. It has looked at more than 100,000 stars. A great search technique to find Dyson swarms, or other hallmarks of advanced ET civilization in orbit around a star. The periodic dip if caused not by a planet, but a irregular (non spherical structure) would encode information about its structure, in the residuals.  As has been discussed in Wright et al. (2016), there are a number of anomalies in exoplanet science which might be from astrophysical phenomenon or possibly from an advanced ET civilization. If we find more than one such anomaly in a system, it would be difficult to attribute it to natural sources.

Therefore, from a SETI point of view there is a LOT of information in these giant data sets from missions like Kepler, TESS, LSST, among others. Citizen Science initiatives do help in this by using human cognitive abilities in pattern recognition to pick out these anomalies and outliers; arguably better than any computer can do.  However, when it comes to automated pipelines, we should quantify their efficacy.

The point I would like to make here, is that in the era where we are transcending the radio region of the electromagnetic spectrum into the optical and infrared, we must make use of these existing big astrophysical missions and include them in our quantification of the search volume probed for ET.  However, I propose that we must add a 10th dimension to this haystack which quantifies the ability of our data pipeline to retrieve these signals IF we were to receive them. By this I mean, if there is a pipeline which is analyzing an existing database to find anomalies, the completeness fraction of that pipeline should also be quantified. By inserting artificial signals into the data, and counting the ones we retrieve, this can be done. However, that is an overtly simplistic view of this problem. This is not an easy task since we do not know the nature of these signals and can hence only hypothesize and to a certain extent – guess.

This way we could include Kepler, and other such missions in our search volume (volume searched by all SETI projects so far) using their actual efficiency and not a mere theoretical one.  This 10th dimension fraction should ideally be close to unity for most searches, however as mentioned in the paragraph above, in the absence of knowledge about the nature of the signal we can only hypothesize using our current understanding of Physics.

Addendum: 2018 – 04 – 30

After further research and work on the 9-dimensional haystack , I realize that in the original Haystack proposed by Jill Tarter in 2010, this ability to retrieve potential signals from the data is exactly what she meant in the modulation axis.

9 suffices. Phew!