Dyson Bubbles on NextBigFuture:
Speculative physics insanity
Unlike the Dyson swarm, the constructs making it up are not in orbit around the star, but would be statites—satellites suspended by use of enormous light sails using radiation pressure to counteract the star's pull of gravity. Such constructs would not be in danger of collision or of eclipsing one another; they would be totally stationary with regard to the star, and independent of one another. As the ratio of radiation pressure and the force of gravity from a star are constant regardless of the distance (provided the statite has an unobstructed line-of-sight to the surface of its star), such statites could also vary their distance from their central star.
Dyson Spheres (Wikipedia):
The star eater
A Dyson sphere is a hypothetical megastructure originally described by Freeman Dyson. Such a "sphere" would be a system of orbiting solar power satellites meant to completely encompass a star and capture most or all of its energy output. Dyson speculated that such structures would be the logical consequence of the long-term survival and escalating energy needs of a technological civilization, and proposed that searching for evidence of the existence of such structures might lead to the detection of advanced intelligent extraterrestrial life.
Since then, other variant designs involving building an artificial structure — or a series of structures — to encompass a star have been proposed in exploratory engineering or described in science fiction under the name "Dyson sphere". These later proposals have not been limited to solar power stations — many involve habitation or industrial elements. Most fictional depictions describe a solid shell of matter enclosing a star, which is considered the least plausible variant of the idea.
The Penrose Process (Wikipedia):
basically a centripedal brake for a black hole. Made out of light.
The Penrose process (also called Penrose mechanism) is a process theorised by Roger Penrose wherein energy can be extracted from a rotating black hole. That extraction is made possible by the existence of a region of the Kerr spacetime called the ergoregion, a region in which a particle is necessarily propelled in locomotive concurrence with the rotating spacetime. In the process, a lump of matter enters into the ergoregion of the black hole, and once it enters the ergoregion, is split into two. The momentum of the two pieces of matter can be arranged so that one piece escapes to infinity, whilst the other falls past the outer event horizon into the hole. The escaping piece of matter can possibly have greater mass-energy than the original infalling piece of matter. In summary, the process results in a decrease in the angular momentum of the black hole, and that reduction corresponds to a transference of energy whereby the momentum lost is converted to energy extracted.
Kardashev Scale (wikipedia):
Soviets tended to think big.
The Kardashev scale is a method of measuring a civilization's level of technological advancement. The scale is only theoretical and in terms of an actual civilization highly speculative; however, it puts energy consumption of an entire civilization in a cosmic perspective. It was first proposed in 1964 by the Soviet Russian astronomer Nikolai Kardashev. The scale has three designated categories called Type I, II, and III. These are based on the amount of usable energy a civilization has at its disposal, and the degree of space colonization. In general terms, a Type I civilization has achieved mastery of the resources of its home planet, Type II of its solar system, and Type III of its galaxy.
Malthusian Catastrophe (Wikipedia):
A Malthusian catastrophe (also called a Malthusian check, crisis, disaster, or nightmare) was originally foreseen to be a forced return to subsistence-level conditions once population growth had outpaced agricultural production. Later formulations consider economic growth limits as well. The term is also commonly used in discussions of oil depletion.
Based on the work of political economist Thomas Malthus (1766–1834), theories of Malthusian catastrophe are very similar to the Iron Law of Wages. The main difference is that the Malthusian theories predict what will happen over several generations or centuries, whereas the Iron Law of Wages predicts what will happen in a matter of years and decades.
The Omega Point (wikipedia):
The Omega Point is a term used by Tulane University professor of physics and mathematics Frank J. Tipler to describe what he maintains is a physically-necessary cosmological state in the far future of the universe. According to his Omega Point Theory, as the universe comes to an end at a singularity in a particular form of the Big Crunch, the computational capacity of the universe (in terms of both its processor speed and memory storage) increases unlimitedly with a hyperbolic growth rate as the radius of the universe goes to zero, allowing an infinite number of bits to be processed and stored before the end of spacetime. Via this supertask, a simulation run on this universal computer can thereby continue forever in its own terms (i.e., in "experiential time"), even though the universe lasts only a finite amount of proper time. Tipler states this theory requires that the current known laws of physics are true descriptions of reality, which he says implies that there be intelligent civilizations in existence at the appropriate time in order to force the collapse of the universe and then manipulate its collapse so that the computational capacity of the universe can diverge to infinity.
Tipler identifies this final singularity and its state of infinite informational capacity with God. The implication of this theory for present-day humans is that this ultimate cosmic computer will be able to run computer emulations which are perfectly accurate down to the quantum level of all intelligent life which has ever lived, by recreating simulations of all possible quantum brain states within the emulation. This would manifest as a simulated reality. From the perspective of the recreated inhabitant, the states near the Omega Point would represent their resurrection in an infinite-duration afterlife, which could take any imaginable form due to its virtual nature.
Assuming that achieving the Omega Point is physically possible, Tipler says this would be accomplished by "downloaded" human consciousness on quantum computers in tiny starships that could exponentially explore space, many times faster than biological human beings. Tipler argues that the incredible expense of keeping humans alive in space implies that flesh-and-blood humans will never personally travel to other stars. Instead, highly efficient uploads of human minds ("mind children" as Tipler calls them, they being the mental uploads of our descendants, or of ourselves) and artificial intelligences will spread civilization throughout space. According to Tipler, this should likely start before 2100. Small spaceships under heavy acceleration up to relativistic speeds could then reach nearby stars in less than a decade. In one million years, these intelligent von Neumann probes would have completely colonized the Milky Way galaxy. In 100 million years, the Virgo Supercluster would be colonized. From that point on, the entire visible universe would be engulfed by these "mind children" as it approaches the point of maximum expansion. Per this cosmological model, the final singularity of the Omega Point itself will be reached between 1018 and 1019 years.
So I was thinking, about the time I got to the article about the Omega Point, that maybe with the cancellation of the human space program, we are reaching a turning point. If, for some reason, society does not completely collapse, perhaps this will be the high-water mark for humanity conquering the stars. Maybe we'll look at this period as the time when we wised up, and stopped sending fragile corpses up into radiated space wrapped in tin foil, just as now we look back at when we used to send men miles under the ground to dig up coal at great expense and many lost lives. Oh... wait a minute.
But seriously, I'm not saying people will never go into space again. Earth orbit is the next area just PRIMED for gentrification. A few starbucks, a couple of leash-free dog park satellites, and we could totally start Facebook groups to complain about the lack of magnet schools at the Lagrangian points. But space exploration? Why bother? What is an astronaut going to do on Jupiter? Sweat in canned air while s/he watches a flag disintegrate under the gravity?
But heck, we're using data-linked robots to bomb people in Central Asia, so why wouldn't we use robots to terraform Titan, and settle for the digital postcard?
"Because it is there?" Maybe space will be solely the rich person's pursuit. They'll spend years and millions of dollars training to go walk on asteroids and lesser-known moons. Then, fifty years later, after they make it back to earth, they can talk about the multi-solar eclipses in the portion of the asteroid belt now named after them with tears in their eyes, while they have a cocktail at the Explorer's Club. Meanwhile, the rest of us will be crowd-mapping Plutonian mineral deposits via our HD, 3D displays from our compounds here on good old earth, for an inflation-equivalent 30 cents an hour.
I am not nearly the impressive nerd-knowledge zone that Exoplanetology or NextBigFuture is, but it seems pretty clear to me that once you surmount the problem of earth's initial gravity and atmosphere, slinging a few thousand camera-equipped smart phones into the galaxy is way easier than trying to ship a human there. At least until we get gravitational drives, or spin-dizzies, or something else I haven't read about on Wikipedia yet. But there's an awful lot of pre-stage Kardashev 1 left before we get there.
More seriously (actually the serious part): I do think we are primed for a lot of new speculative thinking about the future of space exploration. Now that the human narrative has been derailed, it's the perfect time to start thinking fresh.
In the meantime, as I said earlier, I'm into fusion power for the helium exhaust. Here's to sending massive structures into the air, only to have them come back down again.