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If you’re aiming to eke out the universe for as long as possible then ‘turning off’ your stars isn’t that good. A better plan would be star lifting. This is, in effect, turning off the star by pulling all of its fuel away (Note: Only very advanced, already powerful interstellar civilisations need apply). It might help to have a Dyson swarm already at your ...


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In a nutshell, a star is an ongoing nuclear fusion contained by gravitational energy. Turning off the star means stopping the fusion. That would mean either removing enough mass to remove the moderation, or freezing the mass to prevent further nuclear fusion. Removing mass would set off the explosion of the star and also weaken the gravitation bounding ...


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Stars run on nuclear fusion, specifically the fusion of protium (plain hydrogen with no neutrons added) into deuterium, a process that, as far as we know, only takes place in the cores of stars (in nature). In the process, on of the fusing protons emits a positron to convert into a neutron. A more complex decay (due to more protons involved) takes place in ...


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Break the biggest starts into smaller ones. That will require disassembly and reassembly. The lifetime of the brightest, most massive stars is in the order of millions of years. But red dwarves might last for trillions of years (see their wiki). That is such a long time that we don't even know if protons would be stable for that long.


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Hmm, it might be possible...but unlikely. To respond to the clarified question (can be found in the comments), let's assume that by "take up the sky" you mean that each planet has almost a 90 degree angular diameter when viewed from the other planet. This will take up 50% of the night's sky. (Getting 100% is impossible due to the curvature of a spherical ...


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Freeze the star in time. According to this https://www.quora.com/If-time-were-to-stop-suddenly-would-gravity-still-apply (Which isn't a reliable source) you could lock the explosions in time, effectively turning the star off. But the gravity would still happen, so all the planets would keep circling. Or I am reading this really wrong, but then, just ...


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It's tricky. The first stage does use an artificial Reissner–Nordström black hole, or other supermassive and robust "shaver" object. This is dropped towards the star and placed in an unstable orbit, near enough to create a workable Roche lobe inside the target star. This allows bleeding mass off the star until it reaches the Roche vertex at the expense of ...


4

Yes an object would appear to get darker as its mass grows. A high mass object distorts spacetime and causes light to be stretched out or "red shifted" as it tries to escape. An object on he cusp of collapsing into a black hole would be so massive, that the light would be red shifted outside the range of human perception. This video explains it better ...


4

Your planet is kicking out huge quantities of radon gas. https://en.wikipedia.org/wiki/Radon Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas. It occurs naturally in minute quantities as an intermediate step in the normal radioactive decay chains through which thorium ...


3

In hard sci fi, what you would actually do is siphon off mass from the star and store it elsewhere (or just use it for other purposes) since smaller stars burn more slowly due to the reduced gravity (which is what drives the fusion in the first place). This is called star lifting. The extreme end of things is to remove so much mass that the force of gravity ...


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I'll start with the easy part, they would see two distinct hemispheres of the sky where in one half the Milky Way fills the sky with thousands of visible stars like what we see, and the other half is absolute blackness to the naked eye. The galactic "hub" would appear as a very dense splatter of stars, and the four spiral arms of the milky way may show as ...


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Short answer? Not really. Longer answer: The intensity of light isn’t altered by gravitational forces. If I shone light onto this hypothetical object the same number of photons would bounce back off it and climb up the gravity well. As the speed of light is the same for all photons (locally, at least!) there won’t be a proportion of photons lost, so the ...


2

Certainly, given some assumptions. If you know the expected spectrum (or frequency, or at least it has identifiable peaks) of the signal, then you can get the relative speed (not velocity) from the Doppler effect. Assuming the object is in orbit (or freefall) around something in the Solar system, you know what speed is compatible with what orbit. Measure the ...


2

Slow down time for the star One idea I've seen in some hard science fiction (especially John C. Wright's books such as The Golden Age trilogy and Superluminary) is to "put something away for the future" by orbiting it just outside the event horizon of a black hole, so that time becomes almost infinitely slowed down for that object. Then when you want it ...


2

Anti-gravity field Fusion in a star’s core relies on gravitational pressure. You simply have to reduce the gravity/pressure to a point where fusion is no longer possible. Of course we don’t know if it’s even theoretically possible to produce anti-gravity, but you can just hand-wave it. In fact, anything which stops time, counters gravity or replaces the ...


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You just have to realise that 85% of all stars in the universe ARE actually switched off by an unknown advanced civilisation. Physicists on earth call these switched off stars "dark matter", so you can see that its already be done ! How it works ? Who knows ? Physicists nowerdays do not even understand what "dark matter" really is, so you don't have to deal ...


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I think if you wanted to stop a huge mass of elements from interacting with each other and protect the planets in the orbit. You would need to either stop time in that area or just absorb their energy completely and put a substitute mass in the star's place. This group could create some super high tech machinery like a dyson sphere. But instead of ...


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Long story short: Spin it very quickly. Short story Long: You want centrifugal force to overpower gravity. Although not very energy efficient, hypothetically the energy could be returned by feeding off the spin later. You'll expand the star without increasing mass, stopping fusion from proceeding further. Of course, the core, where the gravity is stronger, ...


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This is more of a side-remark that the lamplighters goal of keeping the universe alive most likely would not have stars as main goal: Near-magical technology or not, in the end you'll always run against time. This time of cause, your deadline crunch isn't the next week, but the end of the universe. But then again, the scale of your goal is on a whole ...


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The answer to your question is yes it is possible. The roche limit for 2 equally sized planets is very close. Close enough to allow a shared atmosphere even. Although that is another question and there are other issues, suffice to say that two planets could orbit each other in very close proximity. However such a situation would not be without consequences. ...


1

Assuming that they were exactly where you describe, you would need to find a way of that system surviving past any extinction events involving supernovae and the like. This could take the form of some kind of field protecting the system. This field would have to use tremendous amounts of energy so either the race that lives there would have to have moved ...


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First i want to make something clear. Basically EVERYTHING produces gravitational lensing, as everything interacts gravitationally with everything. Even light. Only problem is, most masses are to small to have an measurable effect, so only bigger and more massiv objects are interesting. Now, there are objects massive and dense enough, that they visibly bend ...


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