40

Our sun produces something like $3.8 \times 10^{26}$ Watts. That requires something in the neighborhood of 600 million tonnes of Hydrogen per second. Getting a similar power from fusion would require a similar consumption of Hydrogen. Even for a culture that could build a Dyson sphere, that's a lot of Hydrogen to get if you are not using a star to do it. ...


31

Your question is like asking "why build an oil power plant with all the related hassle, when we can chop wood and light a fire?". The answer is: the order of magnitude of the produced energy. A star emits Petawatts of energy, while a fusion power plant can produce Megawatts, several order of magnitude less. And a star saves the hassle of harvesting all the ...


16

To power nuclear fusion, you need hydrogen. The overwhelmingly largest hydrogen reservoir in any solar system, and conveniently an already working fusion reactor is its star. In other words, there is far more energy to collect from a star than you could ever hope to generate in reactors.


11

So, I'm going to frame challenge this, and say "no alien civilization entirely surrounds their stars with solar collectors." Piecewise assembly Here's the thing about a Dyson Swarm: It's not a single massive project that returns nothing until it's complete. All you need is solar-orbiting structures that (also) collect solar power, and some sort of orbital ...


7

The human mind is more limited than the AI we can create. In our life span, we can only learn so much, achieve so much, and contain so much info, but a benevolent AI can spend tens of thousands of years learning and expanding its own capabilities. At some point the human mind will become too limited to conceive the sciences needed to advance our technology,...


7

The commonly given reason for building any version of a Dyson Sphere is because the civilization needs an amount of energy comparable to the output of their star. A Dyson sphere captures a significant fraction of that ouput, and does it more or less passively. I would posit that a civilization could not create a Dyson sphere without first having fusion (...


6

Psychological Reasons Why do people climb mountains? It is dangerous and dirty. There are more safe and efficient ways to get exercise. There are more safe and efficient ways to get to the top. Why do people buy Lamborghinis? A Toyota Corolla costs substantially less, carries more, is more comfortable, and uses less fuel. Why do we keep building more, ...


5

Defense. Your civilization has built up its system. It can meet its energy needs through fusion and more esoteric sources. But the sun is aging and as it ages, it becomes brighter. https://en.wikipedia.org/wiki/Stellar_age_estimation#Luminosity_increase_and_the_Hertzsprung–Russell_diagram The civilization does not need all that energy. Really does not ...


5

It doesn't matter. The civilization fell. The inhabitants forgot everything. It is now irrelevant why and how exactly it fell; it is irrelevant because nobody knows, so the specifics of the decline and fall are now lost in the mist of time. Examples: There was once a great power in the Levant, which endured for thousands and thousands of years. But ...


5

In reality, examples for the behaviour you describe exist. Yet, your question asks for possible motivations to start such a cultural evolution. I want to present two possible ones: First, by considering only external motivations/pressure in your question you seem to forget about one of the most imporant internal motivations and driving forces for human ...


5

Steam-Powered Weaponry Long before black-powder cannons and weapons were commonly used in medieval Europe, Archimedes invented steam-powered cannons. Essentially, they were small brass cannons with a tank filled with water which was heated. This caused the tank to fill with steam and, when enough steam had built up, it would be released into the barrel of ...


4

Armoured knights and other highly skilled warrior societies such as the Japanese samurai and the Ottoman Janissaries were already under stress starting in the mid 1400's as the "Infantry Revolution" began. The issue isn't weapons per se, but rather the introduction of weapons and tactics which allowed farmers, townsmen and others with relatively little ...


4

I think Liam Morris's answer about Steam-Powered Weaponry is a really good starting place, but I feel it does not fully represent the more specific question of how weapons would have advanced. Original gunpowder cannons, like the original Steam-Powered cannons, were garbage. They were in many ways worse than the catapults and ballistas of their time, but ...


4

Pain, Suffering, and Medicine People get desperate when they suffer. Diseases are everywhere. You can't develop modern medicine without modern technology. A parent watching their child suffer and die painfully is (thankfully) considered a rare occurrence in our modern world. In fact, I'd encourage you to look more into child mortality rates - the number ...


3

First, I would say that the terms like 'stone age', 'bronze age' and 'iron age' are pretty vague. It's not the only natural progression of events, but rather the accident of the history of the whole region of Eurasia and Northern Africa, that was interconnected pretty early. Even if we take a look at the Mesoamerican civilisations, the division is much more ...


3

Only the slaves survive. Your advanced civilizations had other species that they kept as slaves - possibly one or more intelligent species from various worlds in their federation. Or possibly these are just a different race of the same species as the masters. These slaves were not educated, taught to read or even to repair or use technology; perhaps they ...


3

Your company's goal rests on the Compound Annual Growth Rate of its profits. If the CAGR is positive for an indefinite length of time, then they will eventually own everything that can be owned, and by implication employee everyone that is employable. How long it will take will be a function of the average value of its CAGR. The rule of thumb is the ...


3

There are many phenomena that hit densely populated, civilized areas more harshly than primitive, isolated ones: Disease: a hard-to-detect, fast-spreading plague quickly reaches all planets with major spaceports within a couple of weeks. By the time transportation is closed, busy planets have already been exposed beyond the point of no return. Any survivors ...


2

A Dyson sphere's warmth isn't about how hot the sun is, it is about how hot the civilization is. The fact it gets its heat from a star is immaterial -- replace the star with pocket fusion reactors within the 1 AU sized shell, and you get the same thermal profile for the structure as a whole. Using Energy is generating Entropy, and Entropy leaks as Heat ...


2

War Even in "not so competitive" environment, humans have been known to enter into tribe fights and the like. so yeah, At one time or the other, your humans will fight. From here on, absorbing harder rocks than your opponent is a decisive advantage. So you will refine "better rocks" eventually leading to metal, eventually leading to weapons, and now your ...


2

At the moment I see two possible variants. It could be a damaged generation ship sent by your advanced civilisation before the collapse. With some damages to data storage, they would lack the historical society technological continuity. Depending on the social processes in the ship and after the landing, they may have very little memories of the original ...


2

The effects of this change would be felt more in post-Medieval period, in 16-17 centuries. The question is also hard to answer because the development of the firearms was not the single factor that changed how the war was waged. There's a multitude of political and economic factors, and it's hard to predict what would happen if you remove just one single ...


1

DECLINE OF KNOWLEDGE As the civilization develops, increasingly AI handles more and more tasks better and faster than the aliens who built them. New designs technologies are developed through evolutionary processes, where different designs compete against each other in virtual environments through millions of mutating generations until a superior design is ...


1

Kardashev III civilisations are either multi-galactic, or they use something like Larry Niven's Megasphere, or a galaxy spanning swarm of Dyson Spheres, or they use a lot of antimatter in every inhabited environment in the empire. Assuming they live on planets and in space habitats all powered by matter-antimatter annihilation and have some form of FTL ...


1

Watch the Lego Movie, remove the "remove lord Business" part and you have something along the lines of what you want I would think. They'd have to basically erase most of history that doesn't make people like them, glorify themselves, and soup up all their good deeds. Dominate the air and basically have a secret force that secretly crushes any opponents ...


1

Not possible Now, I could go on for a while and explain why it's not possible because very powerful countries like America have anti-monopoly laws and countries like China use state-owned everything, so they're basically impossible to contend with. I could explain that having successful monopolies on several product would lead to competitor sabotage which ...


1

No explosives, eh? Well, if you are going to change how chemistry works on your world, people will wonder about basic life processes too. Anyway, other medieval-level advancements could be: Metallurgy Longbows, crossbows and ballistas were already capable of penetrating armor, fortifications, and ships. These weapons stored kinetic energy in wood or fiber, ...


1

There are two general areas of advancement. The first is Technique or Fighting Styles. Depending on how armor advances, the weapons used might grow more massive or might become much finer -- mattock or two-handed sword v. epee or daggers. Depending on the situation and opponent, soldiers might opt for nimbleness and speed and striking at vulnerable spots ...


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