Cosmic Natural Selection

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If you regularly read this blog, you already know that I believe adaptive evolutionary processes explain system order in the universe. There does appear to be a unity between how systems evolve (whether they be chemical, biological, cultural, technological, etc.). In this sense, selection-like processes generate order in the natural world that many cultural groups assumed was intelligently designed. But can selection be extended to explain the universe itself?

Before humans knew that there were other planets in the universe, many people believed that Earth could only be explained by intelligent design (e.g., God). However, we now know that the Earth’s existence can be explained by probability. There are likely way more than sextillion planets in the observable universe, so it is not necessarily surprising that one suitable for complex life exists. In fact, it would not be surprising if billions of planets suitable for complex life existed just within our own galaxy.

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But people who make the God-of-the-gaps argument never really go away. Now that it is intellectually bankrupt to argue Earth (or life, or our star, or our solar system, or our galaxy) was intelligently designed, many turn to the universe itself. As physicists have pointed out, our universe is well-designed for the emergence of intelligent life (although not that well-designed).

Therefore, it is the job of 21st century science to uncover the mysteries as to why our universe appears to have the physical constants it does. At the moment, the theory is far ahead of the empirical evidence (unlike the situation in evolutionary biology). A dominant theory proposed to explain our universe’s physical constants is Cosmic Natural Selection (CNS). This theory, first explored by physicist Lee Smolin suggests that:

black holes may be mechanisms of universe reproduction within the multiverse, an extended cosmological environment in which universes grow, die, and reproduce. Rather than a “dead” singularity at the centre of blackholes, a point where energy and space go to extremely high densities, what occurs in Smolin’s theory is a “bounce” that produces a new universe with parameters stochastically different from the parent universe. Smolin theorizes that these descendant universes will be likely to have similar fundamental physical parameters to the parent universe (such as the fine structure constant, the proton to electron mass ratio, and others) but that these parameters, and perhaps to some degree the laws that derive from them, will be slightly altered in some stochastic fashion during the replication process. Each universe therefore potentially gives rise to as many new universes as it has black holes.

The analogy with how selection operates in biological systems is impossible to miss. Given that this is how complexity is generated by other natural systems, it seems logical that this could be the case of our universe (within the multiverse). In fact, a study published this month in the journal Complexityposits that Smolin’s CNS theory would mathematically be in concordance with the production of universe’s increasingly likely to produce black holes (and therefore universe’s conducive to complex life).

Let that sink in. If Smolin’s theory is true, our universe exists the way it does because of a cosmic natural selection between universe’s within a multiverse of universes with different physical laws.

But all theories need empirical evidence. There is currently no evidence for the existence of either a multiverse or successive generations of universes that transmit their fundamental constants. And it’s possible we won’t have that evidence in the near future (or ever).

Either way, I’m optimistic. Advances in physics theory are likely to further support the idea of a multiverse and the CNS. And I wouldn’t bet against CNS being lifted from theoretical obscurity. The idea has a certain Copernican principle to it. Just as scientific inquiry revealed that our planet, solar system, and galaxy were not particularly special, it seems increasingly likely that scientific inquiry will do the same for our universe as well.

What do you think of Cosmic Natural Selection?  Let Cadell know on Twitter!

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Should We Send Messages to Space

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Should we purposefully transmit messages to space? That is the question posed by a team of earth and space scientists in the February 2013 edition of Space Policy.

The question has been raised because various independent groups have been sending purposefully directed high-intensity messages intended for extraterrestrial intelligences (ETI), or METI’s.

The authors of this study made two conclusions regarding METI:

1) The benefits of radio communication on Earth today outweigh any benefits or harms that could arise from contact with ETI

2) Current METI efforts are weak, mostly symbolic, and harmless

But are the answers to independent groups sending messages into the cosmos really that simple? I mean I think it is fairly obvious that the potential for ETI in our galaxy should not deter our species from continuing to improve our communication abilities. We have no evidence to support the idea that there are intelligent civilizations in our galactic neighbourhood, much less evidence to support the idea that there is an ETI civilization that poses danger to our existence. However, expanding Earth’s radiosphere and directly sending messages into the cosmos are two very different things. For example, SETI astronomer Seth Shostak has claimed that, due to decreasing signal strength our radiosphere is not detectable beyond five light years. Whereas purposefully directed, high-intensity messages significantly increase Earth’s detectability beyond the radiosphere.

Essentially, this is the reason SETI pioneer Philip Morrison believed that we, “the newest children” in the cosmos, should be passive and just listen for a long time. We should not ‘shout at the cosmos’. We should not explicitly make our presence known before we know the types of intelligence that may exist.

This is a very complex issue. What should we do moving forward? Should we be engaged in an active search for ETI? Or should we be passive?

For me personally, I mostly agree with astrophysicist and science fiction author David Brin. He supports the International Academy of Astronautics Second Protocol for dealing with Transmissions from Planet Earth. This protocol states that:

all of those controlling radio telescopes forebear from significantly increasing Earth’s visibility with deliberate skyward emanations, until their plans were first discussed before open and widely accepted international fora.

To me, this seems like a reasonable position. If we are to purposefully send a METI, that message should be first discussed by an international panel of experts in astronomy, physics, biology, anthropology, history, and politics. And the message should be collectively sent as a message from Earth and by Earth; not from an independent collective. As David Brin stated, no one should feel free to:

broadcast from Earth, whatever, whenever, and however they want.

On the other hand, there are those who would prefer to completely ban METI’s; I disagree with that stance. Don’t get me wrong, I see wisdom in the perspective that we should remain silent, passively listening to the cosmos for thousands of years, before sending messages into a cosmic environment we are just beginning to understand. However, I feel as though we should send controlled and well thought out messages from our species and planet for two main reasons:

1) If there are highly advanced civilizations in the Milky Way, they would know we are here by studying the physical and chemical patterns of our planet, regardless of our radiosphere.

2) I believe it to be probable that any civilization with the capability of traveling to another solar system would not do so with the intention of eradicating life and high intelligence.

The first point is simple, not controversial, and easily explained: a sufficiently advanced civilization could easily detect the presence of our civilization by analyzing the spectrum of reflected ultraviolet, optical, and near-infrared sunlight for our planet’s surface. They could also, perhaps more easily, become cognizant of our existence from artificial nighttime lighting and the unusual chemical composition of our planet due to the excessive burning of fossil fuels.

The second point is far more complex, certainly controversial, and not easily explained. Biologists have often warned that contact between species that evolved in different ecosystems often leads to one species going extinct. Likewise, historians have argued that “first contact” between more advanced and less advanced civilizations have often led to disastrous inter-human relations (e.g., slavery, colonialism, civilization collapse, etc.). From this reasoning, they often conclude that if we make our presence known to a vastly more advanced civilization than our own, we are placing own existence in extreme peril.

However, consider the following: as our species has become more knowledgable and technologically advanced, we have also moved strongly in the direction of compassion, altruism, and the inclusion of all within the protection of law. I believe that this is directly tied to satiation. As we create a world of abundance; a world with drastically reduced levels of hunger and poverty, we elevate our cultural ideals. David Brin referred to this as:

an abstract sympathy, unleashed by full bellies and brains that are capable of seeing enlightened self interest in the long term survival of the world.

Natural selection is the driving force for the creation of our biosphere. It may be that natural selection is the driving force for all biological evolutionary processes in the universe. Natural selection permits populations to evolve via differential survival rates. And although we are a very young species, we are already close to releasing our species from this process. In essence, natural selection is permitted to operate because of resource scarcity. But as we continue to raise the standard of living for our speciesas a whole, we accelerate ourselves into a world where we all live long enough to reproduce. Differential survival rates will no longer drive our evolution. As a result, we also accelerate ourselves towards a world free of the byproducts of resource scarcity (i.e., extinction, war, slavery, etc).

When we create science fiction work depicting human-alien conflict, we are projecting biological system conflict produced from a world governed by natural selection. But the interaction between two highly advanced technologically-based systems will not likely be governed by that type of system conflict. A new, more intelligently directed form of evolutionary change should take the place of natural selection. Surely, any species with the capability of visiting our planet would have long ago released themselves from the biological tyranny of the process that created them.

As many scientists have pointed out, including theoretical physicist Paul Davies, biological intelligence is likely to be a fleeting phase in the evolution of the universe. If this is the case, it stands to reason that any civilization able to receive our messages and visit our planet would undoubtedly be post-biological. This essentially means they would be post-singularity. And a post-singularity species has not only lifted itself from a world governed by differential survival, but has also lifted itself from finite sentience and death. Therefore, I would not expect conflicts produced by the mechanism of natural selection to dominate an encounter between us and an advanced space faring civilization.

At least, that is my reasoning, and it is why I fully support a controlled, globally agreed upon form of METI. I think the benefits of discovering extraterrestrial intelligence and making “first contact” would outweigh the risks.

That being said, I am sure many would disagree with me. Perhaps it is foolish of me to assume that all advanced intelligent species would have lifted themselves from natural selection and tend towards extraterrestrial altruism. But that is why we must have open dialogue about METI. We can’t tolerate random independent groups to send messages without first consulting the global community. If we send messages we must be prudent. And, from my perspective, prudence would be making sure that any message is sent from Earth and by Earth. No one should be allowed to send whatever messages they want, whenever and however they want.

What do you think?  Let Cadell know on Twitter!

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“Earth-like”

Earth-Like Planets

The search for an Earth analogue is heating up. And although we may have to wait for the James Webb Space Telescope to see another Earth, indirect methods are bringing us closer and closer to finding an Earth-like exoplanet every month. These findings are also bringing us closer to estimating the number of Earth-like planets in the Milky Way (e.g., study 12).

The latest research, and for some the most exciting, was the discovery of Kepler-62e. Kepler-62e is a planet located approximately 1,200 light years away from Earth in the Kepler-62 star system. This system is composed of a smaller and cooler star than our Sun, and is accompanied by five known planets, two of which are rocky worlds in the stars habitable zone.

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From the limited data available to astronomers at this point in the detection process, Kepler-62e has been touted as the “most Earth-like” planet known to date. In fact, by utilizing the Earth Similarity Index (ESI) equation Kepler-62e scores a 0.82 (scale: 0-1.0). That score matches the unconfirmed exoplanet candidate Gliese 581 g (Figure 1).

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Figure 1 – Current Potential Habitable Exoplanets

ESI is calculated using data on the mean radius, bulk density, escape velocity, and surface temperature of an exoplanet. In the popular science media a high ESI (~0.80-1.00) is code for “Earth-sized planet within the habitable zone.” In essence that is what everyone means when they say “Earth-like.” But a growing number of scientists, myself included, are beginning to realize that we are getting way ahead of ourselves. At the moment we have no way of understanding an exoplanet’s geophysical history, present state, or the dynamics of the entire star system. Astronomer Phil Plait recently tempered enthusiasm re: Kepler-62e by stating there are too many unknowns to call it Earth-like yet:

Kepler-62e could have a thick CO2-laden blanket of air, making its surface temperature completely uninhabitable, like Venus. Or it might not. We just don’t know yet, and won’t for quite some time.

In short, more data on Kepler-62e could radically alter its ESI number from 0.82 to 0.44! And that is not even factoring in data on how a radically different solar system would affect Kepler-62e’s development and present state.

This frequent, and perhaps cavalier, use of the term “Earth-like” has caused some astronomers concern. Astrobiologist Caleb Scharf recently forced us to consider what is meant by “Earth-like” when used in the context of exoplanet discovery:

Utterance of [Earth-like] can evoke all sorts of images. It may make us think of oceans, beaches, mountains, deserts, forests, fluffy clouds, fluffy bunnies, warm summers, snowy winters, the local pub, or the fabulous hubbub of the local souk. But this is typically far from the meaning attached by scientists. It can simply indicate a planet with a rocky surface, rather than a world with a thick gaseous envelope. It can mean a world that is roughly the same mass and density as Earth. It can mean a planet orbiting a star like the Sun. Or it can just mean that we got bored of saying things like ‘a two-Earth mass object in a close to a circular orbit around a roughly 4 billion year old main-sequence star that is similar in mass to the Sun’.

For me, Scharf adequately articulates the complexity in this galactic search. He also reminds me that we still must be humbled by what we can’t know at this point in time. Our estimates on the number of Earth-like worlds are going to be in constant flux this century because our data will be imperfect. All we need to do is remind ourselves of Earth’s history to know our current data are insufficient to label an exoplanet “Earth-like”. Despite the fact that our planet’s orbit and size have been relatively static, it has gone through phases (and will go through future phases) that we would consider inhospitable.

On a final note, we must also remember that our planet has the current temperature, chemical composition, and general climate it does because of the biosphere. Life, as far as we know, creates an “Earth-like” world. So perhaps, moving forward, the term “Earth-like” should be reserved for planets that we can tell are operating in a Gaia-like way. By that I mean that we should only call a planet Earth-like if the light elements (e.g., carbon, nitrogen, sulphur, and nitrogen) are being dominated and controlled by biology.

What do you think about our search for another Earth?  Let Cadell know on Twitter!

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Life Before Earth?

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A few days ago biologists Alexei Sharov and Richard Gordon published a paper that sent shock waves throughout the academic community. In their paper titled Life Before Earth they propose that life originated before the formation of our planet. But just in case that wasn’t radical enough, they further state that:

adjustments for potential hyperexponential effects would push the projected origin of life even further back in time, close to the origin of our galaxy and the universe itself.

In my last post I discussed the transition from non-life to life. However, no where in that article did I discuss the timing of that transition. The dominant view at present is that life originated ~3.5 billion years ago. This estimation comes from direct and indirect evidence of prokaryotic (single-cell organism) activity in Western Australia and South Africa. Although it is hard to prove empirically, most biologists are confident that life on Earth did not exist before this period. This is because between 4.6-4.0 billion years ago Earth can best be described as a chaotic hellscape of magma oceans and planetesimal collisions (i.e., not the best place for RNA replication).

But this latest paper by Sharov and Gordon claims life existed before earth (before even the formation of our galaxy). To be precise they calculate the time of origin for life to be 9.7 ± 2.5 billion years ago. For context our galaxy is ~8 billion years old, and our solar system and planet is 4.6 billion years old.

How could this be?

The authors propose that biologists have neglected to acknowledge the “cosmic time scale” of life. In their paper they posit that in terms of genetic complexity life has grown exponentially (they measure genetic complexity by the number of non-redundant functional nucleotides). Prokaryotes, eukaryotes, worms, fish, and mammals were included in the authors study sample and genetic complexity was plotted on a logarithmic scale (Figure 1). With these data they found that genome complexity doubled every 376 million years. They conclude that if genome complexity doubles at this rate prokaryotic complexity could not have been achieved by 3.5 billion years ago. Both Sharov and Gordon blame biologists of presuming a rapid primordial evolution in order to fit the time scales required by our planet’s age.

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Figure 1

Within this new proposed framework the authors suggest that this exponential doubling time is an inherent evolutionary process accelerating quickly with new, more efficient forms of information storage than genomes (e.g., highly complex brains, language, books, computers, internet). Now I am definitely someone that believes exponential growth is an inherent property of evolutionary processes. I am also someone that thinks evolutionary processes generally tend towards greater and greater levels of system complexity (even though recent research has demonstrated that this is not always the case). However, more than doubling the time of the origin of life proposes a radical re-imagining of life and our universe. Such a proposition demands tremendous evidence. I commend Sharov and Gordon for proposing a bold idea and approaching the evolution of life from a novel perspective, but they did not provide us with tremendous evidence.

Biologist PZ Meyers was first to point out that they cherry picked their data. They did not include many organisms that would have completely thrown off their logarithmic scale. Furthermore, even if the logarithmic scale with all organisms plotted remained unchanged it would not be scientific to assume you can project it back to single nucleotide replicators that existed 9.7 billion years ago. Finally, biologists have only started to understand what is and what is not functional within the human genome. Therefore, we cannot assume that measuring genome complexity based off of our current understanding of functional non-redundant nucleotides is useful.

Unfortunately the claim that life originated 9.7 billion years ago might destroy the credibility of both the paper and the authors. I say unfortunately because within this paper the authors actually make a profound claim that I agree with:

The Drake Equation of guesstimating the number of civilizations in our galaxy may be wrong, as we conclude that intelligent life like us has just begun appearing in our universe. The Drake Equation is a steady state model, and we may be at the beginning of a pulse of civilization. Emergence of civilizations is a non-ergodic process, and some parameters of the equation are therefore time-dependent.

Recently I wrote about why I think it is highly probable that we are the first intelligent civilization to develop in our galaxy. My main reasons for thinking this are:

A) Our universe was not always well-suited for the evolution of life

B) Biological evolution requires billions of years of planetary stability

C) Biological evolution can produce trillions of species without ever selecting for high-intelligence and civilization

There are actually many more reasons why I think this is likely so I suggest reading my entryIntelligent Life in the Milky Way if you want to know more about it. Either way, my line of reasoning is certainly in line with Sharov and Gordon’s assertion that “intelligent life like us has just begun to appear in the universe.” Although they come at it from a slightly different perspective, I obviously find this assertion profound and compelling.

In the end I think Life Before Earth is worth a read if you are interested in learning more about Sharov and Gordon’s claims; but I am personally not sold. Biologists may never know the precise historic pathway of inanimate to animate matter and the specific materials present on the prebiotic earth, but I still think a 3.5 billion year origin for life is more likely than a 9.7 billion origin.

In the future biologists do need to demonstrate how biological evolution was able to produce highly complex prokaryotic genomes in a relatively short period of time. There could be a number of currently unknown reasons for this that do not require a single-nucleotide replicator with pre-galactic origins.

That is not to say that life could not have originated completely or partially from space. The idea that asteroids with complex organic compounds seeded our planet during the late-heavy bombardment 4 billion years ago is quite possible. But positing the chemical compounds necessary for life existed 9.7 billion years ago requires more evidence than a logarithmic scale with cherry picked data points.

What do you think?  Let Cadell know on Twitter!

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Intelligent Life in the Milky Way

Over the past few years astronomers have been making considerable progress on estimating the number of Earth-like planets we should expect within our own galaxy. The most recent study by a team of astronomers at the University of Auckland claim that there are approximately 100 billion. This estimate increases the likely number of Earth-like planets by 82 billion. A study published by astronomers from Harvard Smithsonian Center for Astrophysics in January posited that there were approximately 17 billion Earth-like planets. In my opinion, I think the 100 billion estimate is probably more reliable. The study produced by the Harvard Smithsonian Center for Astrophysics collected data from measuring dimming of planets orbital periods, whereas the study produced from the University of Auckland collected data from gravitational microlensing. Gravitational microlensing is a more effective method for finding smaller planets with Earth-like orbital periods.

However, whether there are approximately 17 or 100 billion Earth-like planets in the Milky Way (or more) the important point is that astronomers now have reason to believe that there are a ton of Earth-like planets. This definitely puts a previously contentious issue to rest in the world of astronomy. In the 1990s and 2000s we had very little to no idea how common Earth-like planets would be. Obviously, these data have tremendous implications for our search of extraterrestrial intelligent life. As a result, these data raise some of the biggest questions we can ask as a species. And in this post, I would like to analyze them.

In short: if we now know that there are several billions of Earth-like planets in our galaxy alone, why is it so quiet out there?

Possibility 1. We are the first

Our universe is 13.82 billion years old. That is a long time. However, our universe has not been habitable for this period of time. The universe has gone through stages of development that astronomers and cosmologists understand fairly well. Throughout the early stages of this development life could not have existed. Furthermore, the first galaxies and star systems were composed of stars that were much larger, less stable, and had shorter lifespans than second and third generation galaxies and star systems. This has important implications for the search for intelligent life because although we have only one case example of how life evolves (that would be us!) I still feel that it is a reliable indicator that biological evolutionary processes require billions of years to produce highly complex life forms. If that is a valid assumption of the time scales required for biological evolution to produce complex life forms then the first galaxies and star systems would not have been ideal candidates for the development of intelligent life. Many of the early stars lasted for 10-100 million years. Complex life requires stable star systems that last for billions of years.

Our Milky Way galaxy is approximately 8 billion years old. If life requires at least 2-4 billion years to produce highly complex life it is still plausible that many planets in our galaxy possess complex life forms and healthy biospheres. However, we also know from our one known case example of life that intelligent life is very rare. Trillions of multi-cellular species have inhabited our planet. Only 1 has evolved meta-awareness and the ability to understand the processes that allowed for its existence. Again, if this is characteristic of biological evolution we should expect most Earth-like planets (that remain stable for more than 1 billion years) to produce a biosphere with no self-aware intelligent species. If this is the case, it is definitely plausible that we are the first (at least in the Milky Way).

How plausible do I think this situation is? I actually think it is highly plausible. Selection for high intelligence is rare in nature. Brains are the most expensive organs. The Milky Way may have billions of biospheres, but only 1 biosphere with an intelligent civilization.

Possibility 2. Intelligent Civilizations have a short life span

Our civilization is very young on the scale of deep time. To accurately conceptualize how young we must turn to the Cosmic Calendar. If the entire history of the universe were conceptualized within one calendar year, modern, sedentary, agricultural human civilization would arrive 13 seconds before New Year’s Eve on December 31st. In this astonishingly short period of time we have completely transformed our planet, landed on another celestial object, and started to explore our solar system with robots. This pace of change is accelerating. If the cultural and technological evolutionary processes that have enabled us to do this are characteristic of intelligent species, we should suspect intelligent civilizations to develop very quickly on galactic scales. We should also suspect them to be very loud. Already, within barely a century of using global communications technology our radio waves have reached hundreds of other star systems (check out a this brilliant atlas depicting the extent of our radio emissions).

I am trying to emphasize an important point here. If intelligent civilizations are common and develop on many Earth-like planets, they must have short life spans because we have not heard them yet. As Ross Anderson of Aeon Magazine has pointed out: “no impressive feats of macro-engineering shine out from our galaxy’s depths.” But if intelligent civilizations develop often and have long life spans (on scales of deep time) we should expect to see such feats of macro-engineering. Could it be that intelligent civilizations have very short life spans?

Robin Hanson of The Future of Humanity Institute believes that there must be a “great filter” between the development of life and a galactic-sized civilization. He suspects that if microbial life is very common in the universe (which it probably is), then the great filter must be between a civilization like ours and a larger-scale multiple star-system civilization.

How plausible do I think this situation is? Actually, I don’t think this is the most plausible situation. I think that once a civilization like ours exists it would take an extreme catastrophe to eradicate it entirely. Almost all potential natural disasters that could erase a civilization like our own would not cause complete extinction. And complete extinction is what would be necessary to prevent further development of our species on the scale of deep time. Perhaps I am being naive regarding this assertion. There may be some great filter and maybe it is the development of nuclear arms. Maybe it is the development of advanced nanotechnology and A.I. Maybe it is something that will exist in a century or two. However, at the moment I think it is more plausible to suspect that intelligent civilizations are rare with long life spans, as opposed to common with short life spans.

Possibility 3. Space Expansion Hypothesis incorrect; Transcension Hypothesis correct

For a long-time many astronomers, cosmologists, and futurists assumed that the natural trajectory for an intelligent civilization was expansion into space. In my opinion this is a foolish assumption. Of course it is possible (in fact plausible) that expansion is the natural tendency for intelligent civilizations like our own. However, we cannot discount the possibility that intelligent civilizations do not expand; they transcend. This hypothesis posits that the reason we do not see any “impressive feats of macro-engineering” in space is because intelligent civilizations turn inwards. Intelligent civilizations may start to compress space, time, energy, and matter (STEM compression) to the point that virtual minds inhabit nano-scales (as opposed to minds inhabiting the macro-scale). Eventually this compression should lead to the ability to exploit the extra-dimensions of space, and perhaps allow intelligent civilizations to escape this universe into a different (or neighbouring) one. If you would like to read an article by the futurist who proposed transcension: read this. If you would like a quick video explaining the idea: watch this.

At the moment the Transcension Hypothesis is quite controversial and untested. To many the ideas seems ludicrous. But many ideas seem radical when they are first proposed. John Smart, who proposed the hypothesis, believes that if Transcension is the fate of intelligent civilizations, we should suspect mini black holes in the habitable rings of spiral galaxies. These mini black holes would be the remnants of “transcended civilizations.” If true, this would certainly explain Fermi’s Paradox and account for the eerie silence.

How plausible do I think this scenario is? To me, this is the most difficult one to make a firm conclusion on. At the moment, I am still convinced that the Space Expansion Hypothesis is correct. But I do not want to assume that it is correct. In the future we may find out more about how intelligent civilizations evolve. If the technological singularity is a “thing” (which I’m pretty sure it is) then we have no clue what our civilization will look like in 100, 200, or 500 years. We may explode into space, or we may explode into the nanoscale. Either way, at the moment I’m going to say that we should suspect robotic expansion to be the expected trajectory of intelligent civilizations. So this would make both possibilities 1 and 2 more plausible.

Possibility 4. Intelligent Life Ignores Us

Arthur C. Clarke famously stated that: “any sufficiently advanced technology is indistinguishable from magic.” Certainly that is true. It would literally be unimaginable for someone 200 years ago to conceive of a smart phone (for example). If there are intelligent civilizations out there (perhaps Type II or III or even IV level civilizations), then they would certainly possess technologies and produce patterns that were impossible for us to imagine. This raises two possibilities:

A) If they wished to remain invisible to us then they could certainly achieve that goal.

B) They could produce patterns that we are unable to detect or recognize.

In situation A) they could know we exist and not care. Or they could know we exist and wish to just observe us from a distance and see what we do. Whatever a civilization (Types II-IV) like this wanted to do they could.

In situation B) organizations like SETI are just unable to detect the types of signals or recognize the types of patterns produced by advanced civilizations. This is an intriguing possibility to me. Consider the fact that we do not know what most of the universe is composed of (e.g., dark matter and energy). If we can’t even understand all natural patterns and phenomena in the universe, why should we suspect to be able to detect patterns and phenomena of advanced galactic civilizations?

How likely do I think these scenarios are? I think that any opinion on these scenarios can only be made by a gut reaction or perhaps a marginally educated guess. I personally think both situations are unlikely. I will say that I think situation A) is more unlikely than situation B). I think it is more likely that advanced civilizations are doing things that we can’t detect. I don’t think there is some advanced Milky Way federation of civilizations that are observing us from a distance. Finally, I will add that I think possibilities 1, 2, and 3 are more likely than these possibilities.

Possibility 5. Faster-than-light travel is impossible

The final possibility is that the universe has a speed limit and there is no way to get around this speed limit. If this is the case then expansion into space makes very little sense and intelligent civilizations would give up on this idea. Instead they simply continue to inhabit their home planet until global catastrophe eradicates them (whether that be self-inflicted or natural).

Of course, light travels very quickly. In fact, light travels so quickly that it can circle our planet 7 times in 1 second. However, even if an intelligent civilization developed a space craft that could travel this quickly, it would still take 4 years to travel to the nearest star system. Developing a civilization connected over these distances would not be feasible, especially when you consider that our galaxy is 100,000 light years across. However, I suppose it would be possible under this scenario for civilizations to expand and disperse. There could be rings of civilizations that diffuse outwards to new planets and then remain disconnected from one another (or very loosely connected — perhaps tweeting back and forth every couple hundred years).

How plausible do I think this situation is? I actually think this is the least likely of all the scenarios. We are not even a Type I civilization and we have already proposed several theoretical models that explore the possibility of faster-than-light speed travel. A few of these ideas include wormholes and the Alcubierre drive. Wikipedia has great articles on both if you want to learn more about them. My point is simply that just because we currently have a poor (or limited) understanding of how to circumvent the speed-of-light we should not expect a more advanced civilization to find this problem insurmountable. I would not be so foolish as to claim it impossible that speed-of-light really is an impossible speed limit to pass. However, I think it is unlikely to be. I think it is a problem that an intelligent civilization could solve if given enough time.

Implications of 100 Billion

The implications of 100 billion Earth-like planets in our galaxy is profound (it may have even more profound implications for the universe as a whole). The knowledge that Earth-like planets are abundant forces us to confront big questions about extraterrestrial life. The point of this article was to explore these questions with some level of depth. I believe that everyone’s opinion on what the implications are will be slightly different. In my opinion, current evidence presents us with five potential scenarios for advanced intelligent life. In this article I have tried to rank them from 1-5 (with 1 being the most probable and 5 being the least probable).

  1. We are the first (at least in our galaxy)
  2. Intelligent civilizations have a short span
  3. Space Expansion Hypothesis incorrect; Transcension Hypothesis correct
  4. Intelligent life ignores us
  5. Faster-than-light travel is impossible

What do you think?

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Another Earth

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Dear Universe, Sincerely Earth

Another Earth

Astronomy is often referred to as the most intellectually humbling academic subject.  When you study astronomy you are confronted with scale, size, and time that is completely alien to the human mind.  We evolved to understand spatial scales of kilometers, not light-years, and to understand temporal scales of decades, not billions of years.

Despite this, it is always important to contextualize the human experience with astronomical knowledge.  And last year was a year of particularly insightful discoveries relevant to understanding our species place within the universe.  In 2012, astronomers discovered: a) the first earth-sized planets, b) an earth-sized planet in the nearest star system to earth, and c) the first earth-sized planet within the habitable zone of its parents star.  These discoveries represent major milestones in the development of human knowledge.  They allow us to better-contextualize our planets relationship to the rest of the universe.

To me, these discoveries provide the first empirical evidence that earth-like planets are likely very common in the Milky Way galaxy (and probably in most other galaxies as well).  As soon as astronomers had the technology and methods developed to detect planets as small as earth, they started detecting them.  In the coming years I expect that we will become overwhelmed with headlines similar to: “another earth-like planet detected.”

Interestingly, a paper accepted yesterday in the Astrophysical Journal Letters provided a statistical analysis indicating that we should find some of those earth-like planets in our cosmic neighbourhood.  Ravi Kopparapu, lead author of the study claims: “we now estimate that if we were to look at 10 of the nearest small stars we would find about four potentially habitable planets, give or take.  That is a conservation estimate.”  Since there are eight M-stars (small stars) within 10 light-years of Earth, we should conservatively expect to find three Earth-sized planets in the habitable zones of their parent star.

For me, these estimates are very surprising.  Last decade we had no data on likely frequency of earth-like planets and relatively little data on frequency of exoplanets.  I was someone who thought exoplanets would be very common (which they are), but I thought earth-like planets would be relatively rare.  But it looks like that guess was off.  And if current estimates are accurate, and there are three Earth-like planets within 10 light-years of Earth, we should expect some BIG discoveries in the next two decades.

Why? Because of the launch of the James Webb Space Telescope (JWST).

I remember a few years ago I went to a special presentation at McMaster University with my granddad and a friend about the first image ever recorded of an exoplanet.  I was excited, but I knew before the presentation started that what we were going to be observing would be a grainy pixel on a dark black screen.  Even our best telescopes are very poor at directly detecting exoplanets (which is why all exoplanet discoveries are made indirectly by either a) detecting the light they bend when they cross their parent star(s) or b) their gravitation effects on their parent star(s)).

However, when the JWST (successor to the Hubble Space Telescope) is launched in 2018, we will be able to directly detect exoplanets within 25 light-years of our star system.  This means that if Kopparapu and others are correct we are going to be able to see images of other earth-like planets in the 2020s.

I’ll let that thought sink in a little bit.

But wait! It gets better.  The JWST can also determine the chemical composition of planets.  This means that not only will we get detailed images of other Earth-like planets soon but also we will likely be able to tell if those planets are home to life.  This is because life creates, transforms, and regulates the biosphere, radically altering a planets chemical composition.  Obviously we will not be able to identify species and get specific biological information, but we would likely be able to tell if they were carbon-based life forms that depended on oxygen and hydrogen for survival (for example).

If this doesn’t get you interested in scientific discovery and the future of human understanding, I don’t know what will.  The discoveries of the past two years in astronomy definitely help us conceptualize our place within the Milky Way.  However, these discoveries make me even more excited for what is just around the corner.  We are on the technological edge of making the most profound discoveries in the history of science: finding another earth.  And if you think about how much seeing a picture of our planet from space did to our understanding of life and our place within the universe, just wait until you see another Earth.

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Also posted via Svbtle:

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Life on Europa

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Our solar system may be host to microbial life on multiple planetary bodies.  Mercury, Mars, Titan, Enceladus, and even some asteroids are plausible candidates.  However, in my opinion Jupiter’s fourth moon Europa represents the most likely candidate for extraterrestrial life in our solar system.  Europa is a moon covered with a 20-kilometer deep ice shelf, but beneath that shelf there is a subsurface ocean 100 kilometers deep.

Astronomers and planetary scientists have proposed traveling to this distant world in the past.  In the 1970s it became evident that Europa would be an ideal location to start our search for life in the solar system.  Since then, several studies have provided us with evidence that Europa could be home to life.  Although Europa is nowhere near our solar system’s goldilock’s zone, it does generate energy from tidal flexing and radioactive decay.  Those sources of energy would not permit a large and diverse photosynthesis-based ecosystem, but it could allow for an ocean of microbial life.  There is also evidence that Europa possesses “great lakes” within its ice shelf that could provide us with a great place to start looking for life.

Despite the promise, funding for an exploratory mission to Europa has been a major roadblock to future research.  It is considerably cheaper (and easier) to send a terrestrial robot to Mars than it is to send a robot that can land on Europa, drill through a dense ice sheet, and navigate a global ocean.  However, I would contend that such a mission should be a top priority for our species.  Understanding the biological nature of our solar system has profound implications for understanding our universe, and our place within the universe.

Robin Hanson of the Future of Humanity Institute views such explorations as imperative for understanding what “great filters” exist between dead matter and cosmic transcendence.  Hanson reasons that such a filter exists because despite the immense size and age of the universe we see no evidence of intelligent life beyond ourselves.  Therefore, it is plausible to suspect that there may be a few major universal obstacles (or “filters”) to the development of such a phenomenon.  Gaining a deeper perspective on where “great filters” exist on the continuum between dead matter and cosmic transcendence could reveal important information about our species probable future.  If our solar system is full of microbial life then we most likely live in a universe filled with simple life; and it increases the possibility that some great filter exists between advanced life and the creation of multi-star civilizations.  However, if our solar system is dead, then perhaps the great filter is the creation of life itself.

Therefore, searching for life in our solar system can be thought of as searching for cosmic omens for our future.

Back to Europa.  Although it seems unlikely that we will design and send a robot to the Galilean moon capable of exploring its deep ocean, it may be possible to understand Europa’s ocean by scanning its surface.

In a research article released yesterday by astronomers Mike Brown and Kevin Hand, they reveal that Europa’s ocean is not isolated (e.g., Brown & Hand, 2013).  Mike Brown stated: “we now have evidence that the ocean and the surface talk to each other and exchange chemicals.”  Kevin Hand echoed this idea claiming: “the surface ice is providing us a window into that potentially habitable ocean below.”

Their study focused on the spectroscopic features on Europa’s surface.  They discovered the presence of magnesium sulfate salt, a mineral that could have only originated from Europa’s subsurface ocean.  From these data they also suggested something even more tantalizing: Europa’s ocean may resemble the composition of Earth’s salty oceans.

Luckily, we may get a closer look at Europa in the 2030s.  The European Space Agency is planning the Jupiter Icy Moon Explorer (JUICE), which is a spacecraft designed to investigate the surface of Ganymede, Callisto, and Europa.  During this mission JUICE should perform the first subsurface sounding of the icy moon to determine the exact thickness of the ice shelf surrounding the subsurface ocean.  How much we will learn about Europa’s chemistry (and biology?) is still unknown, but if the ocean and the surface are “communicating” with each other, it is likely that we will be able to learn a lot from the surface alone.

Either way, the more we find out about Europa, the more unbearably excited I become about future research missions.  Robert Pappalardo, an assistant professor in the Laboratory for Atmospheric and Space Physics at the University of Colorado seems equally optimistic about pushing for further exploration of Europa:

“We’ve spent a bit of time and effort trying to understand if Mars was once a habitable environment.  Europa today, probably, is a habitable environment.  We need to confirm this… but Europa, potentially, has all the ingredients for life… and not just four billion years ago … but today.”

Curiosity could still discover evidence for life on Mars (although I’m not holding my breath).  But all evidence leads me to conclude that Pappalardo is correct.  Europa probably is a habitable environment today.  There may be ecosystems on Europa.  And being able to study an island of life that evolved independently from Earth’s could help us answer so many questions about the universe and humanity’s place within it.  Of course, I am not advocating for the reduced funding for Mars-related exploratory missions.  But more funding for the exploration of Europa could be the best science-investment our species can make at the moment.

You can find out more about our future if you follow Cadell Last on Twitter.

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