Saturday, December 30, 2017

Asteroid Defense

We live in a fairly benign solar system. Earth has not had a major asteroid impact for 60 million years, however, that one was an extinction event. Large asteroids hitting an inhabited planet can create large shock waves that sweep through the atmosphere, megatsunamis that can cover almost all of the land surface, dust to fill the atmosphere and block photosynthesis long enough for most plant life to die, vulcanism at the impact site or at the antipodal point, or simply pumping so much heat energy into the atmosphere that non-aquatic life mostly dies out, as well as near-surface dwelling sea life.

In a solar system with more frequent extinction events, with the events happening more frequently than the recovery time needed by life on the planet, asteroid impacts might simply result in almost uninhabited planets, with only single-celled organisms or perhaps small creatures remaining. Is it possible that these are the norm? If so, it could prevent any alien species from ever arising and taking on the job of traveling to other solar systems beyond their own. Earth, as an exception to this norm, would be alone in the galaxy.

Asteroid impacts consume asteroids. Each time an asteroid hits a planet or a satellite, it is destroyed and there is then one less asteroid to impact a planet later. Asteroids do not typically form after the formation time of the planets, so any period of heavy consumption will free up later periods to have periods long enough for intelligent life to form. Astronomers like to talk about the Early Heavy Bombardment, when there were many more asteroids than now, and very many of them were hitting planets and satellites. One might assume it was a sort of random process, and try to figure out the decay time of the rate. If it was short enough, an alien planet might become free of asteroid impacts early on, and easily proceed to evolve all manner of life. If it was long, meaning the cleaning process to remove asteroids did not work very quickly, asteroid collisions would be spaced out so that impacts, not being common initially, did their work for a long time.

Where the asteroids are, and what type of orbits they occupy, makes a great deal of difference in this cleaning process. If there were only a few large asteroids, and they occupied stable orbits in reference to a couple of shepherding gas giants, there would be no collisions, just like we do not expect Mars to hit Earth any time soon. The only problem is that this doesn’t work as well with tiny bodies like asteroids, as there is likely to have to be some dissipative forces to move planets into stable orbits, relative to the gas giants. Asteroids are too small to have enough of these, as they would go as a second power or higher of the mass of the asteroid. Thus asteroids just keep the orbits they were born with, unless they do a gravitational slingshot with a giant planet. They may be in the vicinity of a stable orbit relative to the shepherding gas giants, but not as close as a rocky planet or something larger.

The sweeping clean of orbital areas should be proportional to the cross section of impact, and a gas giant has hundreds of times the cross section for collision that a small planet would. Thus, those orbits which intersect the gas giant’s orbits are likely to get swept clean early on, but not the orbits which intersect the small planet’s orbit. The orbits from which a gravitational slingshot can happen are those which will be swept clean early, so the later periods of a solar system would be when asteroids were concentrated in the areas where there were minor planets, which are the ones where life can form.

Let’s do some numbers on asteroid collisions. First, suppose there was an asteroid in an orbit similar to Earth’s, fairly circular, in the same stable notch caused by the gas giants. That notch might be of the order of a quarter of the distance from the mean orbital radius of Earth to that of Mars. The cross section of Earth compared to the cross-section of the notch, assuming it is circular is of the order of ten to the seventh. If the difference in periods is about ten percent, this implies the cleaning of Earth’s co-orbital vicinity is short compared to the age of the solar system. But for asteroids not in co-orbit with the Earth, another factor, comparable to the radius of the Earth and the radius of its orbit, about a million, comes into play. This makes the cleaning time much longer than the age of the solar system, and implies that for some solar system like our own, with an Earth-sized alien planet at something like the radius of Earth from its star, asteroids will be coming for the whole lifetime of the solar system.

As soon as an alien civilization became expert at astronomy, it would realize this peril existed. Probably there would be geological evidence of the same thing. Thus, asteroid defense would be considered. Is it feasible that an alien civilization could prevent an asteroid from hitting their planet?

Destroying a larger asteroid is probably impossible, but fracturing one into two pieces might work for some of them. However, the destruction operation is likely to involve large amounts of explosive, which means that the resulting course of the pieces is uncertain. This would therefore have to be done far away from the planet to allow the pieces to go far wide of the alien planet. Other asteroids, larger ones, might be impossible to fracture. Diverting them would be possible, if their orbits were sufficiently precisely determined.

Before any destruction or diversion can happen, the asteroids would all have to be located and tracked. Those with the possibility of crossing the orbital radius of the alien planet would have to be tracked more precisely. Could the alien planet find the resources to do this? If the number of asteroids was in the millions and their orbits ranged over the whole solar system, they might not.

The other defense, a backstop to anything else, is to make self-sufficient outposts on other planets or satellites so that if there was a large collision with an asteroid, it would not spell complete extinction of the alien species. This raises the question of whether in a typical solar system, if a very competent and dedicated alien species could figure a way to sustain life on at least one other planet or moon in the absence of support from the home planet. Would doing that leave any signatures that could be detected from Earth with a sufficiently large telescope or other observing devices?

Saturday, December 9, 2017

Alpha Pair Strategies in Alien Civilizations

Many animals here on Earth use alpha pair strategies to control reproduction in times and locations where scarcity prevails. Primates, canines, birds, and others have been observed using it, and there are probably many others as well. In short, the strategy involves the formation of a group of one species, usually incorporating both sexes, which hunt or forage together. There is an accepted strategy for selecting an alpha pair, who are the dominant animals of the group. They get the first food and are the only ones or the preferred ones to breed. Others in the group may serve as assistants, or protectors or nurturers of the alpha pair’s children. There may be a second tier, the betas, who get some of the privileges that the alphas get.

This is not the same as territorial domination, but it may co-exist with it. With territorial domination, a pair, or a single sex of a pair, may take actions to exclude others of the same sex and species from hunting or foraging within an area controlled by the alpha. With the hunting region divided into territories, some animals of the species will get none, which is the equivalent of them not achieving alpha status and having reduced chances for breeding. The alpha pair strategy and territorial domination achieve the same goal over the long term: animals who can achieve dominance feed better and breed more. Successive generations will emphasize the traits involved in the competition, rather than traits necessarily concerned with survival in the environment.

Alien civilizations face the threat of idiocracy, or some other type of dysgenics, once they pass the industrial revolution and affluence takes hold. With a negative correlation between reproduction rate and any positive attribute, the average of that attribute will decline with time. The period between when affluence hits at least part of the population and the time when genetics is taken control of after the genetics grand transformation is when the population is vulnerable to this effect. It may be that no response is given, even that no notice of the problem exists in some particular alien civilization, or it may be that they debate what strategy should be followed to abate it.

The only government reproduction policy that has been effected here on Earth is the one-child policy by China. For the period 1979 until 2015, only one child was allowed for many women, and forcible involuntary contraception implantation or sterilization was used to enforce the rule. There were numbers of exceptions, allowing typically two children, in cases where a child was handicapped, or even if the first child was female. This policy had debatable results, as reproduction rate was already declining before the policy, and it has declined in some other areas which did not have such a policy. Most likely, it exaggerated an already strong trend toward lower reproduction rates. This type of policy is ostensibly neutral toward dysgenics, in that it allows the same dysgenic effects to occur as would occur without them, but perhaps reduces their effects by disallowing large families.

To control this problem, an alien planet might have a similar policy. But can alternatives exist? Is it possible that an alien population might be descended from pre-intelligent animals that employed the alpha pair strategy? Humankind’s exact ancestors are long extinct, but related animals, the higher primates, have strategies of this kind, or something similar, such as the bonobo’s alpha female strategy. When and why might it be lost, and would the same transition necessarily occur in alien populations on similar planets?

Reproduction rates on the gene or chromosome level are determined by two factors, survival of the individual carrying those genes to reproductive maturity, and then reproduction of the individual. The transition to a different reproductive strategy might occur with the transition from an individual hunter-gatherer culture to a clan hunting culture. Hunting large prey which requires the cooperation of a group of hunters means that there must be some tendency toward equality of activity or sharing of the rewards of the hunt. This sociological trend is referred to as the ‘big man’ strategy of food-sharing, in which status, and therefore leadership, is given to the person who arranges for others to eat. This means that survival to a degree is now decoupled from individual capabilities, and these capabilities are sorted out for reproduction in a different way. Individual hunters reproduced because they were good at hunting and therefore found mates. This might be correlated with strength or balance or tool-using ability. Group hunters all share in the spoils of the hunt, and leadership of the group is given to the individual who organizes the hunt the best. These qualities are mostly mental, although obviously good physical characteristics are needed. Thus, intelligence is supported if there is a breeding strategy that rewards the hunt leaders.

If the group is large enough, it cannot reproduce sufficiently if an alpha pair strategy is followed. Population will decline and hunting of large prey will become more difficult with a smaller group. However, if there is a multilevel hierarchy, and reproductive rights only go to the alpha and betas, then reproduction might be adequate to maintain the population of the group and allow it to continue to preserve itself and its strategy. This policy is vulnerable to the departure of the non-selected, either in pairs or in groups, in a schism of the group. Polygyny or polyandry would tend to make the formation of the schism less likely, as would the provision of food from successful hunting. If hunting is difficult, staying for the food might outweigh leaving for reproduction opportunities.

From what limited pre-historical resources we have, it appears that humankind shifted to a monogamy strategy early on, and did not follow any type of alpha pair strategy. This left them vulnerable to dysgenics unless there was not a negative correlation with capability, but positive. The positive correlation solves the problem completely. So the question to ask about is what leads to a negative correlation of productive capability with reproduction? To see if any of these strategies might be profitably used by an alien civilization requires some more thinking about the timing and causes behind the changes in human society.

Saturday, November 25, 2017

Crustal Fragments as Asteroids

Consider a solar system with a planet or dwarf planet somewhat smaller than Mars. If it is large enough, when it forms there will be a great amount of heat generated, meaning there will be separations of elements and compounds, and ore mixtures as well, in the core and crust of the planet. The largest glob will likely be an iron and nickel mixture, which would form the core of the planet. If it stays warm enough for long enough, compounds not very soluble in this metal will separate out, and assuming they are lighter in density, will rise to the crust. The crust will have all the interesting materials in it. The core will be fairly homogeneous, but the crust will have different ores separated out, provided the elements to make these up were there in the beginning.

Thus, small planets deep in the solar system, where dust would collect, would be treasure-troves of minerals, some of which might be very important to an alien civilization which had passed the point of being able to travel throughout their solar system.

As far as mining of inner, metallic planets goes, they do not need to be very small for mining to take place. Having no atmosphere may make it easier or harder to do mining, and that is not clear now. But smaller planets, with no atmosphere, would be vulnerable to the rain of smaller asteroids that happens in the early days of a solar system. Many of these would simply pulverize the surface. Those which came in on a grazing trajectory, if the size and speed were right, might chip off some piece of the crust and transfer enough momentum to it so that it escaped the gravitational pull of the small planet. This is a crustal fragment.

A larger planet could conceivably give rise to a crustal fragment asteroid as well, but via spallation rather than a grazing impact. If a large asteroid were to impact a larger inner planet, the shock wave from the impact would travel through the planet, arriving at the opposite point from the impact point. Perhaps it could have enough energy to blast some material past escape velocity, and possibly some of this material might still be intact, that is, some chunks of crust go flying into solar orbit.

Mining asteroids is thought to be a possibly profitable venture, in the sense that the retrieved material is worth more than the cost of retrieving it. For a crustal fragment asteroid, the materials might be much more valuable than an asteroid which simply has the average material of the solar system at some radius. There could be a hundred times more valuable ore on a crustal fragment asteroid than on a usual one. What would be important if finding which was which. This might require visits by some small robotic ship.

Suppose there was an asteroid, formed from one of the crustal fragmentation processes, which was of the order of a hundred kilometers in size. If it were explored, and there were sources of rich uranium ore in the asteroid, it might be able to form a self-sufficient colony of aliens there. Using the uranium as an energy source, the only energy source, could enough energy be generated to provide a habitable environment, where every other material had to be mined from somewhere on the asteroid and transformed into useful materials? If this is possible, a temporary colony could be established, either independent or part of some multiplanetary organization. How long could alien civilization last on the asteroid? Until the uranium ore was depleted so much that it could no longer supply the energy needed to power the entire asteroid and all its necessary activities, of mining, transporting, refining, manufacturing, and all the multiple activities needed to provide a habitable environment.

How likely is it that there would be one or more of these crustal fragment asteroids in an average solar system? We don't know what average is yet. We don't know what asteroids are in our own solar system, so the data is pretty sparse. At best, we can indicate it might be possible.

What might be the orbital characteristics of a crustal fragment asteroid? Ones which are formed from the grazing impact process would have something less than the orbital radius of the incoming asteroid, the one which hits the small planet. That could have been in orbit similar to the planet which was hit, meaning the resulting asteroid would also. However, in the early days of the formation of a solar system, some asteroids might be shot into orbits out of the planetary plane or even retrograde. This happens because of the interaction of the major planets with the small bodies co-inhabiting the solar system. It should be quite rare, but possible.

The spallation situation might serve to give the spallation fragments a higher speed that the incoming asteroid, if the shock wave was focussed sufficiently. Is it possible that it could be given solar escape velocity, and leave the solar system? Is it possible that later interactions with large planets could slingshot it out of the solar system? The later is certainly possible, and the former, maybe. Either way there is a process by which a crustal fragment asteroid could become an interstellar rogue. Since the crustal fragment asteroid is formed in such as way that its orbital parameters could be unusual, this is not too hard to imagine.

This means that for an alien solar system, there might be rogue crustal fragment asteroids passing through it, laden with massive amounts of uranium for energy and other crustal materials for manufacturing. Could an alien civilization, able to travel around its own solar system and very famiiar with mining asteroids, manage to get to such as asteroid before it passed through their system, and establish either a robotic colony or one comprised of some very brave colonist aliens? Only if they had prepared such spaceships in advance, so they could simply concentrate on getting their ship there and down on the surface in the months that the asteroid was present in their solar system.

They might be able to make small adjustments in its trajectory from solar system to solar system. If there were a sufficient number of this type of rogue asteroid passing through their solar system, it would mean that we should not be looking for some giant saucer-shaped ship for visiting aliens, but instead a large rock.

Friday, November 24, 2017

Rich Clouds, Poor Clouds

It seems that normal stars do not produce the amounts of heavier elements, those higher in atomic number than iron, that are observed in the galaxy. Some other source is indicated. One theory involves a collision between two neutron stars. This might be effected by starting with a binary with two neutron stars. In a binary with only one neutron star, it eats up the atmosphere of the other star. But a neutron star has no atmosphere similar to a normal sequence star, so one cannot strip mass from another. They have little to do but radiate energy and eventually collide, leading to another type of explosion.

This makes sense, as higher elements are formed by neutrons being added to lower elements’ nuclei, and a neutron star is nothing but neutrons. An explosion would lead to the rapid formation of elements, but the spectrum would be quite different from that of a stellar interior, where elements are kept in equilibrium by a very different set of processes.

One question this theory raises is how well a binary can survive a supernova explosion of one of the two stars involved. Perhaps a well-separated binary could survive it, with only a orbital change, perhaps from near circular to an orbit with large eccentricity. Would the first supernova strip off part of the atmosphere of its binary companion, reducing the amount of fuel for it to burn, and thereby hastening the second supernova? This theory of binary neutron stars raises many intriguing questions.

Binary stars do form fairly frequently, so it would make sense that some of them would have two stars which could both evolve into neutron stars. It’s not exactly clear what would happen if one of the stars became a black hole, just barely. Perhaps the same type of collision would also add to the heavier elements.

A fairly obvious question arising from this is: Are clouds uniform in the production of double neutron star binaries? Are clouds which are larger or smaller, more or less dense, more or less turbulent,more or less spherical, hotter or colder, dustier or more gaseous, more likely to produce these special binaries? There are many parameters by which clouds can be described, and it would seem some of these would affect the production of predecessor stars to neutron stars, and binaries to boot. If these factors do play a role in the relative density of these binaries, then around the galaxy there would be, sometime into the lifetime of the galaxy, clouds which are rich in heavier elements and clouds which are poor in heavier elements.

If the technology development of an intelligent species requires the presence, on the planet, of a certain amount of heavier elements, this means that some clouds in the Milky Way are more prone to civilizations which can eventually travel to other stars, and other clouds are too deficient to allow any intelligent species to climb high enough in technology to do this.

Clouds are much larger than solar systems or intersolar distances, so this means the galaxy might be like a large continent, part of which was habitable with rain and rivers and vegetation, while other large areas were barren deserts. Similarly, it would mean that travel within one’s original cloud might be much easier than from one heavy-element-rich cloud to another. Huge distances would have to be traveled, in comparison to the typical interstellar ones. Just to provide some food for thought, suppose the distance between good planets was 100 light years in a rich cloud, and the distance to another rich cloud might be 10,000 light years. While it might be reasonable to travel the first, the second might be simply too far. Thus, the galaxy would be necessarily divided into pieces which cannot communicate between one another.

The heavier element distribution is an additional galactic distribution factor on top of the diversity that already is known to exist, with different major components such as the bulge and the disk, and the variations known to exist in the disk with the rotating spiral density waves and the gulfs between them. Cloud density variations are huge to begin with, and with this latest theory on the peculiar ways in which heavier elements are formed, there is yet another factor contributing to the geography of the galaxy.

It should be possible for an advanced alien civilization to map out the distribution of heavier elements in the galaxy, using large wide spectrum photon collectors. They would therefore know, before they made any decision as to seeding other planets or doing anything else interstellar, just how much territory they could operate in. They might find out that they are in an extreme situation themselves.

If the density distribution of heavier elements is very peaked, in other words, the processes that make heavier elements, such as the proposed neutron star collisions, are quite rare, and there are only a few pockets within the galaxy where there are higher densities of these elements, then they might find that there is no hope to seed the galaxy. Basically they might find they were in one pocket, that there were no other similar solar systems within that pocket, and the nearest other pocket was on the opposite side of the galaxy, much too far to travel to under any circumstances at all.

This distribution may be yet another surprise awaiting Earth scientists as they explore the galaxy. Right now in our history we are just beginning to understand the galactic environment that we live in, and the question that has caught our fancy is the possibility of life originating on other planets. For this we search for some attributes which might be signatures of life. But it could very well turn out in a few years or decades that we realize that we are indeed located in a very unique corner of the galaxy and are the only ones alive and civilized at this time. The galaxy is too harsh a place for life to evolve and develop a technological civilization except in only a tiny fraction of the existing solar systems.

Another implication of this is that heavier elements might take billions of years to accumulate, so that if we had come into existence five billion years later, the galaxy might have many more alien civilizations, traveling from one star system to another or at least communicating between one another. It is too bad we can’t wait around for all the excitement to begin.

Sunday, November 5, 2017

Rogue Asteroids

In current news, it was reported that Earth astronomers have detected their first interstellar asteroid within the solar system. Temporarily named A/2017 U1, its size has not been determined, simply its trajectory. It traveled in from the north of the ecliptic, passed by the sun within Mercury’s orbit where the orbit was bent back toward the north, and on its way out of the solar system it passed within 25 million kilometers of Earth. This latter fact allowed it to be detected by our sky survey instruments, which are looking for near-Earth asteroids.

The size was bounded by maximum 400 m diameter, as otherwise it would be less faint. There is no albedo measurement, so the true size will stay unknown. Let’s throw caution to the wind, and try and understand the implications of this detection. If we say an asteroid with diameter between 300 and 400 meters would have been detected, can this be used to figure out the number which pass through the solar system? The sky survey telescopes can see this object out past 25 million kilometers, but perhaps not detect it initially. Let’s simply suppose that this is the only one of this size which passed through the sphere of detectability of this radius during the last twelve months. Neptune’s orbit is about 180 times this distance, so by looking at cross-sections, we might say that of 32 thousand penetrations of a sphere of this radius, only one would go through the Earth detectability sphere. This means that of the order of 32 thousand asteroids in this size range come through the solar system each year.

If we assume that the size distribution of interstellar asteroids is the same as the asteroids in our solar system, this size range represents about one thirtieth of the total asteroid population with diameters greater than 100 m. So, a little multiplication tells us something like a million asteroids bigger than 100 m shoot through the solar system every year. We’ve seen one.

This number could be off by an order of magnitude or even two. If the sky survey astronomers were really lucky, and this was the only asteroid to come through the detection sphere in a century, then everything would be 100 times too high. But the simplest guess is that this is not the one year when it happens, just that there was not much interest in such objects before, and the detection rate was affected by the attention given to them. Now things are different, and the sky eyes will be looking for the next one.

This asteroid could have been formed similarly to a orphan planet, just condensing out in interstellar space from a small cloud that congealed. Probably it was instead formed in a solar system, and then chucked out in the early days of orbital interaction. There could even be some late time interactions which propel an asteroid from a solar system. We don’t live in any unusual part of the galaxy, just a normal section of a spiral arm, and so it would be reasonable to assume that other solar systems have similar amounts of interstellar object penetration. What would an advanced alien civilization make of this?

One thing they could do would be to use the asteroids as free shipping objects to other solar systems. Put some memorial on an interstellar asteroid, and a million years later it might pass through another solar system. Stars move around a lot, so it might be hard to write something that would be meaningful as to where the memorial was inscribed, but perhaps that problem would be solvable if some dating were possible. Is there anything in the galaxy that tells time?  We can date supernovas and nebulae formed by them by determining the relative speed of the nebula gas, and backtracking the trajectory to find out the date when the supernova exploded. This might be accurate enough to enable some announcement in the memorial as to when the alien civilization inscribed it.

To get the memorial out to an interstellar asteroid requires some high-power propulsion. This asteroid we see is going at about 25 km/sec relative to the sun. For comparison, LEO velocity is 8 km/sec and it is still within Earth’s gravitational well. To comprehend better what launcher requirements are, think of putting a multistage rocket into space outside of the moon’s orbit. The payload of the rocket would have to include a lander, plus control systems able to bring it into orbit near the interstellar asteroid. This would have to be done within a period of a couple of months, between detection and departure of the asteroid. It exceeds our capability significantly, but we haven’t even been launching extraterrestrial rockets for a century yet. It should certainly be within our capability within another century, probably much less.

Digging into an asteroid would provide a radiation shield for anything that the alien civilization wanted to send to another solar system. Digging machines would mean a much larger payload however. It would be good, for such a massive mission, to have as much lead time as possible. However, doing a sky survey requires a telescope that can be oriented and scanned over large sky areas. Using a kilometer sized telescope rules out rapid scans. Thus, the task of landing on an interstellar asteroid and creating something there within the allotted time is certainly technologically challenging.

Could something more significant be done with these opportunistic travelers? Perhaps if there was a rogue planet nearby. If we assume the ratio of planets to asteroids is the same in those early solar systems that were launching asteroids as in our present day solar system, perhaps one millionth as many planets would get launched on interstellar trajectories as asteroids. So, there is some possibility that one will come by. It is also quite possible that the dynamics of planets is such that there is a much lower probability of launching a planet on an interstellar path than an asteroid, so the number might be a billionth instead of a millionth. If this is the situation, we shouldn’t expect a planet anytime soon.

If there was one, and it had an energy source such as large amounts of uranium ore, it might be possible to put a robotic colony on it that would be self-sustaining. It is barely conceivable that such a rogue planet could be used on a seeding mission, especially as there is no way to choose the target solar system or the arrival time. More likely, memorials will be the only thing possible for these star-traipsing asteroids and planets.

Thursday, October 26, 2017

The Bubble of Life

Let’s continue exploring the case where life is hard to originate, meaning it starts itself almost nowhere, but is easy to evolve, meaning once you start it, it just doesn’t stop.  If an alien civilization realizes this is the case, and decides they want to do something about it, they can undertake seeding on all nearby planets which can support the life they begin there.  So, after they have had enough time to seed all the planets within the range capability, what would there be?
If you looked at a three-dimensional map of the galaxy, with red dots for planets with life and blue dots for planets without it, you would see a large disk with a central bulge, all blue, and somewhere in the disk there would be a little red bubble, the bubble of life.  Somewhere near the center of the bubble would be the home planet of the alien civilization.  Seeded planets take billions of years to evolve from simple seed cells to new civilizations of intelligent aliens, so for some billions of years, the seeded planets wouldn’t be capable of sparking new bubbles.  During those billions of years, the galaxy would be rotating and shearing, so the bubble would not stay round, and proper motions of the stars involved would make it enlarge itself and become less distinct.  The alien civilization would likely be long gone, and their home planet would have reverted to just one more planet with life.

Suppose Earth was nearby the bubble, and was a bit younger that the seeder’s planet, so that Earth blossomed into an advanced civilization after the seeders had done  their work and proceeded to become extinct.  This, of course, is some time in our future, if we are lucky and don’t make too many emistakes.  What would we see as we examined our surroundings?  If we were a half-billion of so years later than the seeders, we would see planets with oxygen atmospheres, or other signatures of life, in something like a bubble around some central point.  This pattern is almost necessarily solid evidence of a civilization that decided to seed life wherever it could. Furthermore, it is not just evidence of life in the galaxy, but of a long-past alien civilization with space travel capability.

There doesn’t seem to be other causes for a bubble of life.  If life could originate easily, instead of a bubble of life, the whole galactic disk would have specimens.  It is the localized nature that gives rise to the idea of a difficulty in origination of life, and the possibility of a civilization seeding multiple other planets.   It’s also hard to imagine something an asteroid striking a planet with life, somehow bouncing off after adsorbing some living cells, which stay alive until the asteroid is somehow propelled out of its home solar system and travels to another, and then has another impact on a planet that can support life, and the impact doesn’t kill the cells, but leaves them in some place where they are viable.   Nor could a nearby supernova blast living cells from one planet to one in another solar system. 
One way to look at this example of seeding is a gift to civilizations that come into existence later.  A later civilization near the bubble of life would have a myriad of planets to colonize, if this were possible and they were motivated to do so.  Colonization in a galaxy barren of life can only lead to a harsh life, probably under the surface of some mineral-rich moon or planet, with no hope of surviving long enough to transform the moon or planet into something like their home world, with the right atmosphere, vegetation and animal life.
What about someone inheriting the mantle of the original seeders?  The oldest stars in the galaxy are a bit better than 13 billion years old, but that doesn’t mean the whole galaxy came into existence that quickly.  The time to form depends on what preceded it, but let’s just say 2 billion years were necessary.  Then the disk of stars might have formed, along with the bulge and the other details.  If a star formed then, and had a planet or a few, one of which originated life, we might be up to 4 billion years.  If it took 4 billion more years to evolve to a space-faring alien civilization, that might be 8 billion.  Then the alien civilization seeded planets, and it is another 4 billion for the second generation of life to reach civilization level.  There could have been a hundred or so seeded planets, and if one of them started seeding a second round, we, at 13 billion, might see a second bubble of life, seemingly growing out the side of the first one.  Since we don’t know the variability in the timing of the evolution of life, or even what it depends on, it could be 13 billion years from the oldest star’s birth is not enough, or if the timing could be shorter, the second round of seeding might be more or less complete, right up to the generation of an observable oxygen atmosphere.  The oxygen atmosphere on Earth came into existence in a geologically short time, so that signal is a good early indicator of a planet with life.  Seeing a double bubble would dramatically confirm our observations of other life in the galaxy, and give us something toward a date of the first generation.

Suppose we can find no bubble of life, no matter how far out we get our giant telescopes to search for oxygen or some other signature of life.  Then we are faced with a decision.  Perhaps we are the only life form that is going to originate in the galaxy.  Should we let it all disappear?  Or should we make it the planetary goal to figure out how to seed other planets, capable of growing life, with some seed cells.  That would be a purpose that might unite mankind, and even carry over into any AI entities that come into existence.  Or we could just figure out how to have a good time until the sun burns out.

Monday, October 23, 2017

Issues with Seedships

Suppose there is an alien civilization somewhere out there, and they revere life. Let’s suppose, just for illustration, that they had an early philosopher-teacher like Buddha, and his teachings were so good, they crowded everything else out. The whole population thinks that “Life” is the greatest good, and they should spend their efforts propagating it. Their planet looks very different because of this belief, but the planet is not that important to the question facing them. That question is simply, how do we propagate life to other planets?

Let’s also suppose that life is characterized as has been guessed in this blog, that it is hard to originate and easy to evolve. Because the alien civilization has long ago reached asymptotic technology, where they understood all there is to know about the universe and its physical laws, they know this, and realize that there are large numbers of planets in the galaxy which could support life, if it had only originated there. But it hadn’t. They also understand evolution backwards and forwards, and realize that if they seeded life on these planets, in a few billion years there would be alien civilizations there, similar in many ways to theirs. They know this because they understand that technology has to develop in a certain set of steps, each one building on the previous one, and civilization is forced to self-organize according to the current technology. All civilizations at the pinnacle of knowledge are similar. So, that gives them a little more impetus to seed these planets.

What they want to do is put some simple cells down in favorable locations on as many planets as they can. How are they going to do it?

The first thing they need is patience. The mean distance to the nearest planets might be 10 or 20 lightyears, and other ones are even further. If they go at 0.1 lightspeed, it’s a hundred years at the least; 0.01 lightspeed, a thousand, and 0.001 lightspeed, ten thousand. Perhaps they live much longer that humans do, but this is still a long time.

If they want to go at 0.001 lightspeed, which is about 10^6 km/hr, they will have to boost their rocket very much. This is fifty times the speed needed to get to low earth orbit, and energy goes as the square of the speed. So, a rocket, if they use that, would have to have 2500 times the energy of a typical current-day Earth rocket. Each power of ten in speed raises energy requirements by 100. 0.001 lightspeed might be a very optimistic goal.

Perhaps one early question would be: is it necessary to decelerate in order to perform seeding? Deceleration requires equivalently huge amounts of energy per mass as acceleration, and the bad thing is that while the rocket is leaving their home solar system, it will have accelerate all the mass needed for the deceleration at the origin planet. So, if seeding can be done at fractional lightspeed, that would save a tremendous amount of resources, energy, cost and construction. Seeding at fly-by speed requires that the seed payload reduce its speed to initially low planetary orbit speed at the very least, so it can begin its seed operations from a good vantage point. There is no hope for it to decelerate by upper atmospheric drag. Too high in the atmosphere would have it slip right through, and a little lower, the energy of fractional lightspeed motion would turn the probe into a molten blob in an instant, and then it would simply vaporize. No cells would survive.

Fractional lightspeed is so fast that using other planets for gravitational slingshot effects produces negligible effects. There are no other tricks to use. Massive deceleration the old-fashioned way is the only thing that will shed enough kinetic energy to get the seed pod to be able to arrive unvaporized.

Deceleration by reverse thrusting has to remove the momentum of the probe, and the propellant has to be present to do this. If a long, slow deceleration is chosen, the thrust of the deceleration can be lower, meaning a lighter weight thruster. So, to minimize expense, it would be best to accelerate quickly near home planet and then start decelerating shortly thereafter. This lengthens the total travel time, but reduces mass requirements.

If that issue is settled, perhaps the next one is how to produce something that can work for ten to a hundred thousand years? The environment is not the most benign. Reliability failures are often extremely diverse, sometimes from multiple causes, and notoriously difficult to predict before the first failure. How would the alien technologists build something for, say, a hundred thousand year voyage when their civilization might not yet be that old? Would having asymptotic technology provide them with enough know-how so they could build such a seedship and be highly confident it would work all the way through the end of the mission?

The answer has to be yes. First of all, they would know the environment in which the seedship would operate, both during the acceleration phase, the deceleration phase, and while it was performing its mission at the destination planet. This is basically astrophysics, utilizing large telescopes and other observing instruments. A kilometer sized telescope could be built somewhere far from their sun, and operated to observe the destination solar system. Other sensors, perhaps huge, could also be built to gain an understanding of the interstellar space between the home planet and the destination planet. Models of the overall operation of the seedship should be completely accurate. They would know, for example, the radiation environment in any specialized package on the ship, both from cosmic radiation and from any radiation sources on the ship itself, e.g. a reactor for power.

Secondly, they would understand the activity and aging of any materials, based on a thorough understand of materials in general. Predicting how, for example, a power converter or a timer would operate over long times should be simply extrapolation of the processes that go on during shorter intervals.

Thirdly, reliability failures in their civilization would be almost non-existent, as the technological know-how would build up over centuries as to the potential root causes of failures. This means that the body of knowledge in how to build reliability into objects becomes asymptotic, just like all other science and engineering knowledge.

A different question arises: is it possible, even with asymptotic technology and access to any materials needed, and a very high level of effort and funding, to build a seedship? Is there an upper limit on reliability that the seedship would exceed?

Saturday, October 21, 2017

The Last Day: Death in Synthetic Civilizations

Recall that a synthetic civilization is used here to mean one which is a mixture of robots, other AI organisms perhaps with no bodies, modified animals with intelligence, new species that the native aliens created to improve themselves in their genetics laboratories, and perhaps some hybrids. There may be no more of the evolved species of aliens left, as they could simply choose not to have any more and only gestate some improved aliens. The new aliens might not be a species, simply individual organisms, but whether they are or not would depend on choices made in the alien civilization. If they conceive of some catastrophes in their future, they might want to make sure they are a species that can reproduce if necessary. There are certainly perils we know about, such as basalt floods and asteroid collisions, which would destroy the civilization but perhaps not all its inhabitants. Thus, having an ability to recover in case something like this happens might be a good insurance policy. Then again, they might simply have a small reservoir of their own species left to share the planet with newly designed creatures.

What would death be like in such a civilization? Robots wear out parts, but parts can be replaced, and any information in the control system of the robot simply transferred over. So, robots are almost immortal but they are not quite; there should be a new word for something which is just a set of replaceable parts. Biological creatures could have organs regrown and replaced, or perhaps a technology of regeneration would be developed which would eliminate the need for such replacements. This would be a sort of immortality, except that damage happens cell by cell, and even the best genetic copying is still going to have errors. There should be cosmic ray damage everywhere in the galaxy, not just on Earth, so they would be subject to that degradation.

Built-in cell death might be programmed away, as microbes do not have it. The process in higher organisms on Earth is that each generation of cells past some starting time chips away at a clock-like mechanism within the cell. The cells are only approximately running at the same rate, but when large numbers of cells reach their end-of-life signal, death happens. This might be written out of higher organisms, but that means that cellular damage, beyond that which can be repaired by the cell’s mechanisms, would accumulate and be inherited on a cell generation level. Thus, gradual degradation appears to be inevitable in biological organisms without some external intervention.

Possibly it will be possible for an alien civilization and their asymptotic technology to have a medical process which involved gradual replacement of the cells with cells grown in a protected environment, where they were largely free from damage, or which were grown rapidly from perfected genetic code so that no damage could accumulate. If these could be substituted by some process in a biological organisms, it would be brought back to a state of youth.

The brain in an organism, assuming it to be a neural net such as all mammals on Earth use, would be a separate issue. Figuring out how to generate new neurons in the brain without destroying the knowledge and capability of the organism might be impossible. Perhaps everyone in the alien civilization will get used to memory loss as time goes on.

Thus, immortality in a slightly degraded sense might be possible for alien civilizations. However, it is not clear that this is a realistic technology, or that the cost of it would not be so high that the civilization would just opt for death and replacement.

If death was part of the alien civilization, there is a question of how it would be handled. Should all biological organisms be grown with genetic code that stretches life to the longest extent, and medical technology, admittedly far beyond what we can imagine, used to prolong it in all cases, both from accidental injury and from senescence? We on Earth know the costs of such medical intervention grows greatly with the age of the organism, so, if costs were a consideration in the alien world, would there be some threshold upon which prolongation no longer was done?

The other alternative would be to go in the opposite direction, and provide some fixed term that each alien could expect to live, at the end of which there would be euthanasia. It is our natural instinct to avoid death, but some cultures on Earth accept it more naturally than others. Could an alien civilization go farther and make it an acceptable way of organizing a life?

In either of these two situations, there would be a date on which life no longer went on for any particular organism, either because medical intervention became too costly or because the alloted term was used up. We might refer to this as a Last Day arrangement, as each alien would understand when his/her/its last day was, and could choose to spend it as they wished.

There could be some coordination with the government, so Last Days only happened once a year, or on some other schedule, and it was turned into a type of celebration rather than the onset of mourning. Could it be possible that the culture could be adjusted so that the natural instinct to try to survive was subdued, and aliens willingly participated in Last Day ceremonies, either on a large scale or on a more private scale?

This has implications beyond the life of an individual alien. If part of their culture was the acceptance that organisms have a fixed length of time, and after that they willingly cease to exist, then they might apply that not only to individuals, but also to species, or to life in general, or to life on their planet, or to their culture. When it comes time to decide if they are going to go and colonize another planet a thousand light years away, or else just let their culture and species go extinct, this thinking may color their choices. “Everything has a lifetime, and our is up. Forget about the stars and let’s celebrate the end of our culture.”

Monday, October 16, 2017

Life: Hard to Originate and Easy to Evolve

Suppose the origination of life happens in the way developed in this blog: only after an Earth-Moon collision, when many organic molecules are created in the inferno, only to cool down and form an organic ocean on top of the water ocean. Asteroid collisions, which are likely common among solar systems, don’t provide enough cooking of the atmosphere’s CO2 to provide the huge mass of heavier organics needed. If that is the case, and the Earth-Moon collision is in itself a rare thing, then life won’t originate, even on planets which are perfectly capable of supporting it.

On top of this, suppose that once life originates, by which we mean cells with external membranes and a DNA-like coding, it simply keeps going despite all the planet can throw at it, like basalt flows and atmosphere alterations, ice ages and scads of tsumanis, dirty volcanoes, and tectonic sheet collisions. These two assumptions taken together, and both are reasonable, mean that an alien civilization looking over the nearby galaxy with some giant telescopes and other interesting sensors, would decide that there are many worlds capable of being planets like theirs, but which didn’t. Maybe none did, or only one out of a thousand. What would they choose to do?

If they had had a Buddha-equivalent long ago in their past, teaching that life was the important thing, no matter what kind, and this belief spread and became the dominant philosophy during their industrial grand transformation, then by the time they reached the pinnacle of technology, there would be no question as to what they should do. They should seed the galaxy, wherever it would work.

There would really be just about no place to go and migrate to. Without life and its transformation of a planet, there are probably insuperable obstacles to an alien civilization going out and colonizing one. There is no dirt, nothing to eat or burn, nothing to breathe, maybe very hot or cold, in short, an unappetizing place to visit. Granted, it might be possible to burrow underground, mine enough uranium to support a colony, but without a logistics lifeline to the home planet, very difficult.

Seeding, on the other hand, might be a piece of cake. A one-way probe with a genetic lab inside could make some generic cells, and then dropsondes to put them into some shallow sea along the coastline. Yes, the dropsonde would have to have a re-entry shield, but this is not difficult. Once in, it would be necessary to wait some billions of years to have a habitable planet, so that can’t be the plan. The plan is pure Buddhism, support life in all its manifestations, even potential ones on a far-away exo-planet, even if it does you no good at all.

Even without a Buddhist tradition, there is little else for the alien civilization to do. It can do its own astronomical calculations, and figure out how long it could last, if enduring to the bitter end is what they want to do. Perhaps their eventual extinction would be easier to accept if they knew there were a hundred other planets that would likely evolve intelligent life. Quite an accomplishment, in some points of view. Taking a galaxy barren of life, and turning it into a future galactic network of civilizations is an accomplishment to dwarf all others. The time necessary to evolve from seed cell to city-building would vary by a factor of two or three, so there may never be many around at any one time to communicate, but there might be some overlap.

Those planets which were the rarity, ones which evolved life on their own, might be left to simply do what comes natural to such a planet, develop a civilization. Where does that leave Earth? We might think we understand the origins of life, but maybe Earth missed the mark, and there was one pre-condition we didn’t have and so life had to be seeded here, some three or four billion years ago. If that is the case, we might look around at all other potential harbors for life and see what other planets were seeded, and how far they have progressed along the expected path. Are we early achievers or the last of the bunch?

On the other hand, maybe we are the unique among the unique, the only planet to evolve life among the few planets which could have, as only we had the formation event, like an Earth-Moon collision. If so, we shouldn’t waste much of our time and resources looking for other civilizations, as there wouldn’t be any. Doing our astronomical homework and figuring out how likely an Earth-Moon collision is would help nail down this possibility, so we know if there might be one more somewhere on the other side of the galaxy or if the total is exactly zero, except for us.

This reinforces the need to figure out what the origination mechanism is for life. If it truly is very, very rare, but planets which could have done it are not at all rare just unlucky in the life lottery, then we have to ask ourselves a question. Do we want to go Buddhist? If there really are no planets with any life on them, sailing around the galaxy trying to colonize something is a long shot. But if we can start up life on other planets, should we? Does life mean something to us, or should we just enjoy our time here on Earth and then blink out of existence without a whimper? One aspect of this choice is that it provides a goal for us here on Earth. There is the terrible dragon of nihilism waiting for those civilizations which have no meaning to their existence. Even if we don’t have to go and seed life on other planets, we can make a choice to do so and adopt a goal for the human species, turning meaninglessness into meaningfulness. There is no way to answer the question of ‘should we’ as there is no shoulds in the laws of physics. There are only choices.

Friday, October 13, 2017

Nihilism in a Synthetic Civilization

Recall that a synthetic civilization is what you get after the genetic grand transformation happens, and it becomes possible to create organisms by designing their genetic code, translating it into DNA or their equivalent, and putting it into a cell and gestating it. It is the equivalent of designing a robot, going to a piece-work factory, and feeding the design into something like a 3D printing device. You turn it on, load it with the software you want, and let it go. Both new organisms and new robots will likely need initial periods in which their brains develop the necessary capability, but after that happens, you have what you wanted.

A synthetic civilization is a civilization, which is defined here as intelligent things interacting in a way to supply their needs, made up of a mixture of organisms and robots, all designed either individually or in groups. It may have aliens in it, who preserve their own species within the civilization, but perhaps more likely, it has an improved version of the alien species, or even just improved aliens, no longer part of any species but completely individual. This seems to be a possible endpoint of the development of an alien civilization, so it is worthwhile asking about it. This post concerns itself with nihilism, which is simply a flavor of philosophy which notices that life has no intrinsic meaning, only the meaning that other intelligent creatures give to it. Another way to say that is that life has not goal per se, other than ones which have persisted since the earlier days of the civilization. Back when things were simply evolving, the goal of life was simple, survive and reproduce. Then this became elaborated into all the subgoals that help that happen.

The synthetic civilization might have a speedbump here because automation will be there to ensure both survival and reproduction are done according to some plan. What does that leave for the aliens, or post-aliens, along with their robots and intelligent organisms (“intellos” for short)? Some of the aliens, robots and intellos may not be very bright, and simply do what they are told by others, but those which are gifted with a high degree of intelligence will appreciate their situation. They may have been trained during their early years, or early days for robots, that their purpose is such and such, but their intelligence would question that.

One of the hallmarks of intelligence is the ability to communicate with other intelligent things. It involves using a grammar, and one of the essential components in a language is the pronoun, “I”. Once an intelligent thing starts talking about ‘I this’ or ‘I that’, it becomes self-aware, meaning, its brain refers to itself as an object or an entity. Concepts of goals, utility, plans, and so on revolve around self-awareness. In a synthetic civilization, the more intelligent of the things that think will wonder about their own goals. They may have been trained to have some, but what keeps the brain in the thing from asking pertinent questions about why do I have such goals, and should I do something to change them.

For the sake of illustration, just assume that the upper intelligence tier of whatever is self-aware in a synthetic civilization realizes that there is no purpose to their existence, and they all are collectively depressed, which is one possible outcome of such realization. Now ask, are these thinking things going to want to travel to other solar systems and colonize other planets or start floating worldships touring the galaxy or seed other planets with the spark of life or anything else connected with interstellar travel? If you have any experience with a depressed person, or have had a period in your life when you were personally depressed, you know the answer. It is ‘No.”

There is a difference between envisioning a synthetic civilization and an alien civilization that has robots and intellos running around in subservient roles. If the alien civilization has not de-speciated, to coin a word meaning moving beyond being a single species, they can still have legacy goals which have been set in earlier eras and which are passed down from one generation of alien to the next one. They are trained in early years to know what to do, and it might include extraterrestrial voyaging. They would be in charge of the society, possibly, and able to command the robotics, including AI this and AI that, and any genetic organisms they chose to construct to help them with their goal. They could manage their civilization with a goal in mind. But in a synthetic civilization, there is no source of goals.

Nihilism can creep in and overpower an alien civilization at any time during or following the pre-genetics, pre-robotics period. That is the last period in which legacy goals can be set in concrete, and plans made to continue them through teaching and training young aliens. At that point, aliens are still constituted as they evolved, still carry the same emotional attachment as during the evolutionary period, but may know better how to preserve traditions, which are a fundamental piece of embedding goals in young alien minds. Neural networks only work one way, and that is the only way that a species can become intelligent, so we can be fairly confidence of interstellar convergence on this point.

Legacy goals can be lost through attrition and erosion, when one or two generations lose the drive to preserve them, and then technology advances to the point where goal setting is no longer something held over from evolutionary days, but becomes one more rational function of the civilization. Legacy goals can be lost from lack of care, or from deliberate or accidental sabotage of the process of preservation of goals, via the meme process. They can be lost because of distraction in a civilization that has developed technology to a sufficient point where all basic needs are met and enjoyment of civilization’s benefits becomes a dominant interest. They can be lost through war between regions or factions or from revolution by castes or some other segment of the population. There are many ways to lose the legacy goals, and only by avoiding all of them would the goal of extraterrestrial colonization or exploration be held. Considering all the loss mechanisms, perhaps nihilism, the absence of meaning in their lives, is a dominant reason why other civilizations stay at home.

Thursday, October 12, 2017

Enormous Black Holes

Ordinary black holes form when large stars collapse under their own gravitational force. Stars start out with fusion fires in their cores, which generates enough countervailing pressure to keep them inflated. When the fuel burns out, the pressure from the high temperatures diminishes, and they collapse. If there is enough matter in the star, the matter condenses to neutronic matter, which is at the density of an atomic nucleus. This results in something tiny, Earth-sized, as opposed to normal star sized. This means the gravitational potential well is much deeper, and even photons have a hard time escaping. With enough matter, they can’t, and we have a black hole. It takes about 10 solar masses to do this. Stars in our galaxy go up to about 100 times solar mass, so there are very many candidates for future black holes. These massive stars burn very hot, so their lifetimes are short, and the galaxy is old, meaning there should be a lot of them around.

If you look at an globular cluster with a good telescope, you will see a million or many millions of stars, all pulling themselves together into a kind of tiny spherical galaxy. If you look closely, the hottest, heaviest stars cluster in the center. That’s simply a result of random motions in the cluster, where one star interacts with another star, sharing angular momentum and kinetic energy. The lighter stars are easier to kick around, so heavier ones lose some velocity and drop closer in toward the center. They don’t loose too much and collapse into a tiny volume, but the average distance to the center drops, and they make the core of the globular cluster nice and bright, yellow and blue.

These stars have been doing it for a long time in many globular clusters, meaning there would be a lot of black holes around, and they would be in the center as well, since their masses are about the same as the heavier stars. But they are invisible. There would be a range of neutron stars as well, also mostly invisible, and since they are lighter than black holes, they would range out farther in the cluster.

The center of the galaxy should have experienced the same phenomena, and should be full of heavy stars and black holes. Astronomers cannot see the black holes there, but they can map the gravitational potential by seeing how fast stars orbit near the core, just like we can see planets moving faster as they are closer to the sun. This provides an idea of how much mass is inside these orbits. For some unknown reason, there seems to be the idea that instead of a swarm of black holes in the center of the galaxy, there is a giant, enormous, single black hole. It would be impossible to tell the difference, and there is no obvious mechanism by which the matter in the galaxy could form an enormous black hole in the age of the galaxy, but the idea persists. A swarm of ordinary black holes could be the source of the gravitational potential, and that is a simpler idea.

But can enormous black holes exist? Do a thought experiment. Forget about time, and just imagine some immensely later time in the universe. Black holes are, so far, known only to be a one-way street for matter, and keep gobbling up anything which ventures too close to them. Suppose you are in the universe after immense amounts of time have passed, and black holes kept forming and kept accreting matter. Now there is nothing left in the universe except black holes and a bit of legacy matter. Sooner or later, actually, much later, black holes get close enough to one another and lose relative velocity, and if this happens enough, maybe quintillions of years, a binary black hole will form and tidal interactions will toss off gravity waves, carrying away the angular momentum, and they will spiral down until they merge. Again, this is a one-way street. So keep watching, and black holes will get larger and larger, but it might be a very long time.

As you keep watching, the average black hole mass will keep getting larger and larger. There is nothing known to stop this. So, from 100 solar masses to 1000 solar masses to a million and a billion. Now you have enormous black holes.

What is going on inside a black hole? The small ones have neutronic matter, as they form from neutron stars. Earth science does not know what other, more dense states of matter might be. At some pressure, do neutrons disassociate into quarks, leaving quark matter black holes? Actually, it there is a state of matter more dense than neutronic matter, it would start forming at the center of a black hole, and as more mass were accreted, increasing the pressure, the core area of quark matter or whatever matter would expand, growing larger and larger. No one has even a faint clue of what the mass required for such a transition might be. Are there further states beyond quark matter? Maybe…

Does something go wrong with the equations of general relativity at these high gravitational fields? Does it break down just like classical physics breaks down when size gets too small, requiring quantum mechanics and similar theories? The important point is, does gravitation cease when density gets too high? This might happen through an imperfection in the theory of gravity, or it might happen from the equation of state of matter at very high densities. In essence, do quarks carry gravitational force, or does it go away when a neutron oozes into a set of three quarks?

If gravitation goes away at insanely high densities of matter, we would have an instability inside a huge black hole. And the change to non-gravitational matter would have to occur at the core of the huge black hole, meaning it would want to rise to the surface. This type of instability is called a Rayleigh-Taylor instability, and it explains why you cannot have a water layer on top of an oil layer. It just inverts abruptly, no matter how carefully you do the pouring. So, if there is a cessation of gravitation inside a single, massive, gigantic, enormous black hole, you have an explosion. It might be called “The Big Bang”.

Tuesday, October 10, 2017

Retro Science Fiction

Retro SciFi is a name invented here to categorize one type of doomer science fiction, where society, in whole or in part, regresses to an earlier state. Technology is abandoned beyond a certain date, or perhaps a bit more finely, such as where electronics is abandoned, but mechanical gizmos keep getting invented and added to the collection of things the society in the retro scifi is concerned with.

This amounts to a very elementary writer’s trick, in that somehow a story or a novel has to be mostly familiar to its audience, with just a few novelties to make the events interesting. If one sets the novel in the recent past, the audience can immediately jump to a high level of familiarity, as we all know how the previous generation or maybe even the previous one to that had to live, what they did with their time and what problems they faced. Even if we don’t, the change back to these eras is not so large as to tax anyone’s imagination. So with this trick, the writer is free to throw in whatever he wants to as the innovative part. Perhaps it is some personal interactions, or a conflict between factions or regions, all conducted within the context of prior technology.

The reason for the abandonment of technology could be anything, after all, these are stories or novels which are wholly imaginary, and written without any restrictions. Could be some war happened, or some catastrophe that was attributed in part to some technology, or people just decided they didn’t like it anymore, or some key resource was exhausted or deeply depleted, or anything at all. This scenario might be considered for an alien civilization, which has progressed farther in development that we on Earth have, and has reached the threshold where the catastrophe happens, and technology no longer progresses, but regresses, either in one burst or gradually, down to some level where the civilization can sustain it, despite the catastrophe.

If we take this theme seriously as a possibility for alien civilizations, it would mean that the expected ordering of grand transformations, maybe starting with the use of fire, and then stone and wood, before moving onto the hunting grand transformation, followed by the agricultural, the industrial, and finally the genetic, after which asymptotic technology is available and the civilization reaches a stasis, would not run to completion. Because we are in the middle of our industrial grand transformation, current retro scifi concentrates on returning to an early phase of industry, perhaps the mechanical part, and never passing into later stages for a second attempt at the climb to the peak of technology. If this was an unavoidable consequence of prior technology development, or inevitable based on some universal evolutionary traits that all alien species would have, then it would certainly answer the question of where all the aliens were. They would all be stuck on their home planets, reduced to very pedestrian lives.

The scenario of technology level peaking and then falling back is a generic one, and does not have to be solely concentrated on the different phases of the industrial revolution. Maybe 99% of alien civilizations run out of large prey animals and slip back down through the hunting grand transformation to being tool-using fruit gatherers. Maybe agriculture doesn’t work on most alien planets for very long because of soil depletion, and so the societies go back to being clans hunting large animals. Maybe something happens with robots after they become highly prevalent, and the usual alien civilization just abandons them and AI as well, and goes back to some age similar to our own present one. Perhaps genetics has some unforeseen side effects, maybe ennui sets in, and the society goes back to having evolutionary reproduction and no new invented species, or even very smart pets.

While it is interesting to think about such possibilities, and certainly much good can come of going into details here, it is more relevant to think about why such a regression would be temporary rather than permanent, and therefore would not be the dominant reason why all the alien civilizations in the galaxy have not visited us. Technological progress has been happening for millennia on Earth, perhaps even for a million years if controlled fire was the first tool that was utilized by mankind’s predecessors. Why does it happen? Because humans and alien equivalents have needs and technology satisfies those needs. Stoicism is the philosophy that espouses not seeking anything for one’s life other than the minimum needed to sustain it. Can such a philosophy last for long? It never has on Earth. Human brains are simply computational devices used to satisfy needs, and seeking such satisfaction is the driving force behind activities, both of humans and necessarily of any aliens, no matter what shape they take.

Yes, catastrophes can happen and wars can occur and revulsion against some change or invention can happen, but as the civilization ages, technology as a means of solving the problem of satisfying needs will repeatedly be advanced forward. The group with the best technology out-competes other groups, if there is any such competition. Popular opinion against some type of technology might last for a few generations, but sooner or later the utility of technology will overcome the remnant memories of why some technology was abandoned earlier. We can expect the alien brain, in any alien species, to have the ability to be creative, and that allows the invention of new technology, or, in the case of a retro scifi scenario, the re-invention of technology. It simply proceeds onward, like water flowing downstream, moving around rockpiles or boulders in its way.

This is once again a reason why science fiction is not a good substitute for alienology, the careful and thoughtful exploration of what alien civilizations might be like. Science fiction has its own goals, principally the income of the authors, while alienology was devised to help understand the possibilities for intelligent life on other planets, and possibly its implications for our own lives.