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Some non-Mayan sane Doomsdays

December 21, 2012 4 comments

Commemorating today’s Mayan un-Doomsday, we might want to look at some actual doomsday scenarios that pose an existential risk to Civilization, Humans and planet Earth. First of all, not all phenomena pose a threat in the long run, and out of those not all lead to an existential risk to Humankind and Earth. The below grid shows us how various threats can be categorized into Scope of risk depending on their Severity

Nick Bostrom’s Scope-Severity grid

Here, point to be understood is that we tend to either overestimate or underestimate various phenomena as threats due to our cognitive biases which make humans fall short of unbiased rationality. Even if we know what all factors are involved, it could prove very difficult to forecast and estimate the risk involved in those, especially of Anthropogenic threats, due to our methodological limitations. For eg., we cannot accurately estimate risk due to Nuclear war as international relations and technology rapidly change all the time, and calculation in conjunction of both might prove limited. Threats posed by Nature are relatively constant, though new threats can always be discovered, and prediction models for these are comparatively better.

Nevertheless, we have quality studies on lot of phenomena and some have been identified as existential risks for Civilization, Humankind and Earth. They can be summarized as follows:

#Extraterrestrial threats

We have come a long way in understanding a lot about Solar system, Milky way and our surrounding galaxies (Humans have observed galaxies as far as 13.75 Bn light years away), and we have estimated some risks coming from outside Earth

  • Meteorite Impact – Asteroids with a 1 Km diameter have impacted the Earth on average once every 500,000 years. The Chicxulub crater, which was theorized to be  responsible for extinction of Dinosaurs 65 Mn years ago, was roughly 10 Km in diameter. There is a forecast that in 1.4 Mn years, the star Gliese 710 is expected to cause an increase in the number of meteoroids in the vicinity of Earth by passing within 1.1 light years of the Sun and perturbing the Comet cloud around the sun, with a 5% increase in the rate of impact on Earth. This is supposed to be a serious disaster for Earth
  • Sun becoming a Reg Giant – As part of its stellar life-cycle, Sun would eventually become a red giant in about 5 Bn years, and in this process, becomes thousands of times more luminous and losing roughly 30% of its mass. After just over 1 Bn years from now, the extra solar energy input due to these changes will cause Earth’s oceans to evaporate and the Hydrogen from the water to be lost permanently to space, with total loss of water by 3 Bn years from now. Earth’s atmosphere and lithosphere will become like that of Venus. Over another billion years, most of the atmosphere will get lost in space as well, ultimately leaving Earth as a desiccated, dead planet with a surface of molten rock.
  • Mercury colliding with Earth – There are simulations that show that Mercury (5000 Km diameter) has a 1% chance of its orbit becoming unstable due to Jupiter’s gravitational pull, and could possibly result in collision with Earth within the lifespan of Sun
  • Andromeda galaxy colliding with Milky way – Andromeda is 2.5 Mn light years away and is moving towards our Galaxy (Milky way) at 110 Km per second. It is estimated that it would collide with Milky way in 4 Bn years, and the collision could eject Solar System into an eccentric orbit altering its shape considerably

Other threats from Space include Nebulae passing through Milkyway which would change Earth’s atmosphere drastically, Dangerous Solar Flares, and Near-Earth Supernovae that could explode within 100 Light Years distance from us increasing Gamma ray radiation coming onto Earth

#Terrestrial threats

These are the risks coming from within Earth that would pose a threat to Human civilization and life

  • Ice Age – Ice ages on earth typically occur between 40,000-100,000 years. Currently, we are living in interglacial period with the last glacial expansion 10,000 years ago after which all civilizations evolved. A future Ice Age would have a serious impact on civilization because vast areas of land (mainly in North America, Europe, and Asia) could become uninhabitable. It would still be possible to live in the tropical regions, but with possible loss of humidity and water
  • Supervolcanic Eruption – The Toba Supereruption, happened around 70,000 years ago was the most recent supereruption which created about 6-10 year-long Volcanic Winter and possibly created a bottleneck in Human evolution with human population reduced to 10,000 or even a mere 1000 breeding pairs. Although not at this near catastrophic level, Volcanic eruption of Mount Tambora(1816 AD) has thrown enough pyroclastic debris and other material into the atmosphere to partially block out the sun and cause a volcanic winter. Such an eruption in future might cause the immediate deaths of millions of people several hundred miles from the eruption, and perhaps billions of deaths worldwide, due to the failure of the monsoon, resulting in major crop failures causing starvation on a massive scale
  • Global Pandemic – This is a less predictable scenario where evolution of extremely virulent pathogens can pose heavy risks for the survival of human civilization. For example, if HIV were to mutate and become as transmissible as the common cold, the consequences would be disastrous. There are numerous historical examples of pandemics that have had a devastating effect on a large number of people, which makes the possibility of global pandemic a realistic threat to human civilization.

#Anthropogenic threats

These are the risks primarily due to Human activity on Earth, and these are the widely studied risks so far, and can be controlled by changing our individual lifestyle and global policy

  • Technology out of Control – Improvements in Biotechnology can take pandemic, chemical warfare to an extreme; Advancements in Nanotechnology can give rise to uncontrolled self-replicating robots; Improvements in Artificial Intelligence can produce unfriendly AI, all of which pose a serious threat to human civilization. We have various organizations established to study and direct these technologies into a safe direction
  • Global Warming – This is perhaps the most popularized threat to humans, life and ecosystem. There are some significant forecasts like Himalayan glaciers disappearing by 2350 AD resulting in famines, which affects half of world population; Agricultural land degradation which is at 40% now, would worsen giving rise to major food crisis all over the world; Deforestation would result in jeopardized biodiversity, disappearance of Polar Ice caps and desertification of Tropical regions, posing serious threat to human civilization. These outcomes are primarily based on Human choice and efforts are being made for Policy reform, Eco-communalism and Great Transition for better sustainability
  • Peak oil – This is a scenario where maximum petroleum extraction is reached, and no viable alternate sources of energy can be used. This would result in a crash-down of agricultural production leading to mass starvation

Apart from the above, there are other threats like Evolution of Superbacteria that is resistant to antibiotics, Overpopulation leading to ecological and economical collapse, Reduction/Extinction of Pollinating agents like bees resulting in the loss of most flowering plants and as a consequence a large number of agricultural crops, Epidemics on Food crops like Ug99 steam rust in Wheat

Learning more about these viable Doomsdays would definitely take away the imagination from an uninspiring Doomsday coming from numerical limits of the Mayan calendar, and make these more creative and poetic, if not realistic. If you ask me, more Facebook spam should be created for these possible threats and more awareness needs to be brought wherever human activity can alter their course. Although Earth won’t be around for more than 2 Bn years at the maximum, it doesn’t mean that Humans can be irresponsible and mess things up and leave a disaster for future generations to live. We don’t want our children to have more diseases, unsafe drinking water, famines or floods

Lastly, there is a philosophical touch to all these apocalyptic scenarios. When Earth is eventually sent into abyss, nothing in the universe would try to save it or whatever left on it. As Carl Sagan says in Cosmos, “The universe seems neither benign nor hostile, merely indifferent to the concerns of such puny creatures as we are”

Further Reading:

Singularity Institutehttp://singularity.org/

Center for Genetics and Societyhttp://geneticsandsociety.org/

More Researchhttp://theconversation.edu.au/

Notes:

1 Light year = Distance traveled by light in 1 year = 10 Trillion Km (Approximately)

Source: Wikipedia

The Relativity of Wrongness

December 14, 2012 1 comment

This post sources from Issac Asimov’s essay “The Relativity of Wrong”. You can read it for the background and context

Scientific method, as popularily misunderstood, doesn’t see the world in absolute “right” and “wrong”. It tries to come up with Hypotheses or Models which try to explain phenomena happening around us and predict events happening with presumptive conditions, using Mathematical framework. A good scientific model should be falsifiable i.e., should mention how it can be proved wrong, should be testable against the postulates with experimentation, consistent with observation of earlier experiments, and if possible, extendible and mathematically economical. So, the property of “wrongness” itself is a desirable feature in any good scientific model, or in other words, a good scientific model is a model which can be proved wrong

Doesn’t this sound paradoxical, that we come up with “wrong” models to try discovering the “truth” behind the things around us? Well, that’s why we need experiments to verify the predictions done by these models, and to validate their postulates, and disprove them in their falsifiability tests. Once the model passes these bare minimum steps, it becomes a Scientific Theory, and is ready to be tested against other competing Theories for a greater understanding of the phenomenon. This cycle goes on and on, until some observation comes up that is inconsistent with the Theory and gets disproved, if cannot be modified. In a nutshell, scientific method tries to choose the “better theory” among the ones proposed till date that is consistent with the observations. This is a basic explanation of how scientific method is, and the individual steps in this process have been so intensively refined over a period of time that some of them are independent areas of study now

Now, what is the merit of this type of process? It’s simple – we improve our experiments and gather new data all the time, and we either need to have a facility to extend our existing theories to fit the new data, or completely throw out the theory if it’s fundamentally inconsistent and start working on a new one. In any case, we need to change our understanding all the time as we improve our quality of experimentation, and become lesser and lesser wrong. We cannot have an all-correct theory that cannot be changed, or shouldn’t be changed, and keep thinking it is the correct explanation and stop at that. This is the only way in which we can improve our understanding and be progressive in our journey of finding the “truth”

So, how does scientific community reconcile abandoning an existing theory and welcome a new one, if it seems so stupid to be wrong till then, and start supporting another theory, which is likely to be proved wrong in future? Let me give you an example for this – Newton’s theory of Gravitation, which had been very popular and established for almost 200 years until precession of Mercury’s orbit was observed. Newton’s theory couldn’t be modified to fit this observation, and Einstein’s General theory of Relativity was able to explain this phenomenon, and it was accepted, abandoning Newton’s version. However, at normal conditions, General Relativity’s equations get reduced to Newton’s theory, effectively validating the old theory as relevant for calculations. Same is the case with Special Relativity and Newton’s laws of motion, and lots of other theories which have superceded their previous counterparts. As Asimov writes,

In short, my English Literature friend, living in a mental world of absolute rights and wrongs, may be imagining that because all theories are wrong, the earth may be thought spherical now, but cubical next century, and a hollow icosahedron the next, and a doughnut shape the one after.

What actually happens is that once scientists get hold of a good concept they gradually refine and extend it with greater and greater subtlety as their instruments of measurement improve. Theories are not so much wrong as incomplete.

This can be pointed out in many cases other than just the shape of the earth. Even when a new theory seems to represent a revolution, it usually arises out of small refinements. If something more than a small refinement were needed, then the old theory would never have endured.

This is the very essence of scientific method, and new theories are improved on the subtler aspects compared to the old ones. “Wrong” is always relative in scientific study, and it’s foolishness to assume that scientific theories are immutable facts like religious scriptures, and that abandoning a theory for a better one makes both theories equally wrong. Rather, as Asimov points out, “in a truer and subtler sense, both need to be considered incomplete”

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