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There are two conditions for the cosmic microwave background to be able to support life: It emits strongly enough at wavelengths required by photosynthetic pigments. It's bright enough to transmit a useful amount of energy to any life out there. If either of those conditions is not met, life cannot survive (as the first stars will not be born for another ...


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Add crust; remove water As you point out, the main difference here is the amount of water present on the planet. This is actually even more dramatic than it initially appears - we're not just comparing surface area here, but instead volumes. That is, how does the volume of the crust above sea level (mountains, plains, etc.) compare to the volume of the ...


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After looking at all of the comments, this is my personal conclusion for the ultimate "world tree". Leaves with very short hairs. These leaves would not only produce energy through photosynthesis but absorb water like roots, where the hairs act as root hairs. With slightly different physiology this is certainly possible. Location in a valley providing ...


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Actually, as the city is described in the book, it is not fully arboreal. If you read the beginning of the chapter 7, book 2 in the LOTR, it describes quite clearly that a lot of traffic goes by the ground - there's a white stone road, a stone wall and a gate in it. Then there are pathways and stairs, and only then the characters come to the glade, where ...


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Regarding circulation, there is an easy solution. In some medieval mines, people used large furnaces situated beneath chimneys to generate an air current. It would have been relatively easy for Dwarves to do something similar. Air would flow into Moria through holes at the base of the mountain, and out through the many chimneys. However, I don’t believe ...


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We, unfortunately, never have enough information about the Dwarves in Tolkien's books. We mostly see them from the outside points of view - either elven in Silmarillion drafts, or hobbit one in the Hobbit and LOTR. There is some information in those books, however, that lets answer some of your questions. First off, I do not think dwarves would just hollow ...


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True underground dwarves would need a source of energy to replace sunlight, and a way to convert it into food. A silicon based life-form like a troll might be able to eat coal directly, but dwarves are mammals. Even trolls would eat their way through a coal deposit in a few generations. I think this would be impossible with the usual iron-age fantasy ...


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You don't need to do anything. You really don't. The visuals in LOTR and the Hobbit show some pretty huge underground spaces, sure. If you want to argue that the engineering involved is questionable, and just stonework couldn't support that kind of vaulting, sure, but the idea that what we see in the movies represents a significant hollowing of the entire ...


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This would be very hard to do, but you could make it work, maybe ... if you're not too strict. Problems: Based on the IAU definition of a planet, your hemispherical planet no longer meets the classification of a planet due to its shape not being consistent with Hydrostatic equilibrium. Most planets are subject to the tendency toward hydrostatic equilibrium ...


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It depends on the size of the planet. A key concern is whether the body is in hydrostatic equilibrium. An object in hydrostatic equilibrium is approximately spherical, although it may become oblate due to rapid rotation. The question, then, is whether the division of the planet places it below the critical size required for hydrostatic equilibrium. It turns ...


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Planets are such because they are in hydrostatic equilibrium. This means that if you would cut it in half, it would crumble under gravity to a spherical shape again. The orientation of the rotational axis has little to do with this.


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First of all, the profile of the continents makes no sense in that world. In our world oceanic crust is denser than continental crust, thus tends to subdue when a it slams against it. And when new crust is created in the rifts, it tends to stay below sea level, and the margins of the separated continents some coincide. This is how one can explain the good ...


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Edit: I did the math and turns out I may've misjudged the sun: it gives more energy than I thought. See edit at bottom. This has partly been answered here: Sentient trees. Can they develop technology? But this question is more of a precursor to that: can such trees ever come about in the first place? I think this requires a definition of "plant" vs "...


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On Earth we come up with biome names to differentiate places that experience major differences. At the same temperature you could have a desert, a jungle, or a prairie depending or precipitation and local organisms; so in your world, you'd just have more named biomes such as a sunjungle, jungle, and darkjungle but a desert may just be considered a desert ...


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Building things requires cognition and agency, which plants don't have. However fungus does seem to resemble something that really looks like a brain; and has actions that seem to indicate cognition. So on a long timescale it's imaginable that it would create enormous underground brains. Similar to the Starship Trooper brain bug. But then there is still ...


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No. Tidal locking near a black-hole (which you'd need for your effect to remain in one place on your planet) is impossible because of: Magneto-rotational instability Black holes exist in an extremely hot, turbulent, and magnetically charged surrounding, IE it's not just gravity tearing you apart that you'd need to worry about. Near a black-hole Velikhov-...


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A river can change its course overnight, if there is a violent storm. Such a storm hit southern England in February 1287, leaving some towns under the sea (Winchelsea), land-locking others that used to be ports (New Romney), and redrawing the course of the River Rother so that it now meets the sea near Rye, ten miles away from its former mouth at Dungeness.


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You don't need 10,000 years to change the river course, It may also happen in a matter of a few weeks if there is a massive earthquake in the region it can change the direction of rivers. (It could be a country-wide impact) for instance it happened to Mississippi In 1811 and 1812, a series of earthquakes emanated from New Madrid, Missouri, and were felt as ...


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10 thousands year is an awful lot of time for a river. Just look at how the Netherlands changed in the last 600 years: Or look at how the Po river delta changed over the past 300 years: The Adriatic sea is called like this because of Adria, a city which was once a big port and now is several kilometers inland. And the examples above only deal with the ...


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If an Ice Age happens during the 10,000 years, rivers could change course drastically. Glaciers can carve mountains in half, and leave behind hills hundreds of feet high. The Great Lakes could just as easily drain to East Texas, Louisiana, or New York as to the gap between Labrador and Newfoundland. Weather patterns can change. For example, the Gulf ...


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Body plan First off, let's talk body plan. Your demons, being roughly human-sized, will need very large wings. Starting with the similarly sized pteranodon, they'd need around a 20 foot wingspan to support a 100lb body. (Very roughly: pterosaur weight estimates are generally somewhat dubious.) Your demons have to support the added weight of horns and arms, ...


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Oxygen is not the only problem when creating a breathable environment. This answer uses only currently feasible or existing technologies While the astronauts in the Gemini and Apollo programs breathed 100 percent oxygen at reduced pressure for up to two weeks with no problems, breathing pure oxygen at earth level pressures is not medically advisable, (...


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I'm guessing that your question about endorheic basins is about the buildup of salt and other minerals. Certainly there are many aquatic animals who live in fresh water and many that live in salt water, but not many who are okay with a change from the former to the latter over time. The solution to that (no pun intended) is a lake that doesn't get the ...


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Crater Lake in Oregon is an example of such. Precipitation is the only source of water, and it has no outflow. Around 100 years ago, 6 types of fish were introduced to the lake by humans. Currently only 2 still exist.


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Take a valley, put-on a geothermal vent and cover it with thousands feet of ice. You get something like lake Vostok. Under high pressure from the ice above, water stays liquid at -3°C. It may have been connected to the sea and is now sealed-off from the rest of the world for millions of years. Despite that, the bottom ice-layer sample reveals richness in ...


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So from a food perspective, it shouldn't worry. Generally, apex predators represent 1/10 of the biomass of it's prey species. If it takes 10 sheep to feed one wolf, and Purple dude uses the Eternity Baubles and the Unlimited Oven-Mitt and claps his hands, you now have 10 sheep for every wolf. There are less wolves on earth than sheep, but the ratio still ...


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Many other answers have addressed the immediate issues around losing half of all living things at once...mass chaos and conflict followed by something of a equalizing period whereby life gets on with the business of...well...living. I'd like to offer that life would actually THRIVE under this circumstance. Plant life: The red in tooth or claw can also be ...


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Zeiss Ikon has a good answer but you also need to bear in mind that some lakes cannot ever become havens for complex aquatic life. For example if the country rock is limestone the water pH may consequently be too high to support the plant life that forms the base of the pond food-chain. Similarly a number of igneous rocks create acidic conditions that have ...


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Real world: Fish lay eggs. The eggs sometimes adhere to the feathers of water birds. The birds fly from one body of water to another, and some of the eggs survive the trip. This occurs with farm ponds -- despite never being stocked, they wind up with populations of (in the American south, anyway) bream and bass, as well as inevitably snapping turtles ...


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Going "poof", i.e. complete removal without corpses, will take away a lot of biomass from the Earth's ecosystems. This will deplete the sources of nutrients, even bacteria will have difficulties to recover, not counting plants and animals. Since the soil consists to a great part of living organisms, the surface of the soil will lower (depending on the amount ...


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A lot of folks have covered a lot of great ground by treating each country as a closed system. However, we also need to consider that warfare at a distance is a relatively new phenomenon and historical precedence doesn't tell us a lot about this. I would expect a number of countries to take advantage of the situation and perform some sort of first strike ...


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The actual losses will be much higher than 50%. Equiprobable distribution of losses means that some passenger planes won't loose either pilot but some will loose both. Planes falling out of the sky not only kill off their passengers but also any unlucky ground dwellers under them. High speed Freeways are going to be deathtraps! Critical tasks such as ...


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Microbe populations will bounce back within days, fungi at a similar rate and plants over the course of weeks to years depending on the size of the organism. That's assuming that their ecosystem still exists and they still have a viable population. Some species will go extinct because the 50% of their population that dies happens to be disproportionately ...


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The Black Death killed 25% of the population of Europe (approximate). This is only twice that, the conclusion is obvious. Initial confusion and dislocation, followed by rapid promotion to fill the gaps, and eventually everything will go on as normal. Conclusion: society will survive.


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Society where? Blue whale society might struggle. If you kill off one krill in every two, you're significantly reducing the density of the food supply. It takes so much energy for a blue whale to feed that they don't bother opening their mouths unless the krill achieves a certain minimum density. Though this has as much to do with krill behaviour patterns, ...


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There is absolutely no problem for the society to survive in your scenario. Killing half of plants and animals will barely be noticed. We kill more than that all the time. Most species will recover within a generation or two. It may take a while for long living species like Oaktree or Blue Whale, but that's not a serious concern. As for human, yes, there ...


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Alright, let's start with a basic premise; if half the humans disappear, more than half the population dies. Like you said, some people are in charge of planes, you only have half the firefighters on duty when half the food being cooked catches fire because there's no-one to take it out... You get the idea. Just to be clear, the first week is going to be ...


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What does history teach us? During the Thirty Years' War the Germanies lost almost half of their population in the 17th century. As we all know, the Germanies eventually recovered and became mighty Germany. Justinian's Plague killed almost half of the people living in the (Eastern) Roman Empire in the 6th century. As we all know, the countries of the ...


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If the terrestrial planet requirement can be relaxed allowing for smaller worlds with fluffier atmospheres, consider two Titan-sized planets in close orbit. With its radius of 2500km, minimal Roche distance of the surfaces is 1100km. Titan's atmosphere at 600km is at mesopause just above upper haze layers. Under the counteracting gravity of the companion, ...


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It’s not completely stupid. If we could manage to make a fusion drive that fused hydrogen to helium (which is much more difficult than the deuterium-tritium fusion that we can’t yet make work), then there would be enough energy available from the hydrogen in the oceans to accelerate the Earth to the necessary 0.2% of light speed (and decelerate at the other ...


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Old memories were overwritten with new job-specific data https://robocop.fandom.com/wiki/RoboCop RoboCop, as he was more widely known, a cyborg with computer and mechanically assisted reflexes, memory and a 'lifetime' of law enforcement programming and a selection of dynamic software for plotting strategies and ballistic vectors in any situation. ...


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Everything inside your brains is electric. Your thoughts are electricity, going from one node to another. And memories, are electricity, just stored. When someone dies, the brains electricity disappears. Think of it like taking a magnet and swiping it over a computer's harddisk. Electrical information is such a fragile thing, and the tiniest disturbance ...


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Your method of breeding seems to be a little bit off. You are saying that you release some smart ones into the wild while keeping the rest, but that is basically the opposite of what you want to do. Also, you don't want to bring in outside genes, because you haven't selected those. What I would suggest is that you release the inadequate ones and let the ...


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My first thought was if you had all the equipment to build such a dome, why not apply it in other ways to provide a more complete survival strategy? But the truth is that it doesn't take much to generate laminar flow. The ultimate problem with this is that fluid dynamics preclude portal style entries and ventilation. Also, I'm not convinced that we fully ...


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You may end up with slightly smarter raccoons by this approach, but nothing bordering on what we'd practically call intelligence. For that you're going to have to set cooperative problems not individual ones. You need to put multiple raccoons into every problem and have the problem only soluble if they all do the right thing, in time they all have to do ...


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Retrograde amnesia is perfectly reasonable side-effect of the procedure itself. There would be considerable physical trauma to the brain from being removed and implanted. Hypoxia would be likely during the process. Blood circulation would almost certainly have suffered at several points. All of these can cause amnesia if they happen to relevant parts of the ...


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Neuroplasticity. A robot body is radically different from a human body, meaning different parts of the brain may need to be retasked to do something completely different. Because the retasking is so extreme some memories may be lost because that brain tissue is doing something else rather than storing said memory. This may especially be the case if we add ...


1

You could supply chemicals which make the neurons in the parts of the brain responsible for our memories retract. And many other such solutions, some of them beyond our current technology. Even better: Don't take the physical brains but scans of their structure in an artificial brain. There, you can change anything as you like. Either solution, though, is ...


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I think your methods will not produce a human level intelligence in raccoons. You will succeed in producing raccoons with better memory, sharper perceptual acuity, better dexterity, possibly more effective puzzle solving skills but not human intelligence. The other animals we share the planet with do not have the capacity to override basic drives. Think ...


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The laminar water flow dome would provide shelter from UV since water is opaque to UV. And it would provide shelter against wind as long as the wind force was less than the surface tension of the water wall. Once it exceeds that, then when the wind start to over come the inertia of the water it would blow the wall into particles of water. A similar argument ...


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