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My civilization is highly advanced Type III and wants to conduct an experiment on a red dwarf. They want to artificially cause it to become a blue dwarf, then a white dwarf and then finally a black dwarf. Black dwarfs haven't occurred naturally in the universe yet because the universe hasnt been around long enough for it to form. My civilization obviously doesn't want to wait that long and wants to create a black dwarf so they can study it.

  1. How would they go about doing this?

  2. What cool name could I call this process?

  3. How long would it take based on the certainty that we CAN speed up the process to something in reasonable time. I'm looking for an arbitrary number. Here is a link to the blue dwarf Wikipedia page which then links to a white dwarf and then a black dwarf.

https://en.m.wikipedia.org/wiki/Blue_dwarf_(red-dwarf_stage)

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  • $\begingroup$ If you want this to go into the range of conspiracy...they could probably fake it. Take a red dwarf and have it orbited by a series of gravity wells that distort the light given by that red dwarf to a variety of other colors. Conspiracy theorists could see their glory days declaring the entire experiment was a hoax ;) $\endgroup$ – Twelfth Nov 23 '17 at 19:47
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    $\begingroup$ Astrophysicist Rhys Taylor was recently asked about ways to cool a white dwarf down to obtain a black dwarf in non-cosmological times. You can read his series of answers here :astrorhysy.blogspot.fr/p/q-a.html#coolthatdwarfyo - to sum it up, it may be barely possible by dropping a zillion micro-wormholes in the white dwarf so radiation can escape through them, effectively increasing the radiating surface and thus accelerating cooling. Even then, it's a very long shot, but no other option seems to have a chance to work. $\endgroup$ – Eth Nov 24 '17 at 12:09
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First things first.

Black Dwarfs

A black dwarf is a white dwarf that has cooled down to be in thermal equilibrium of the space around it. It's just a dense lump in thermal equilibrium with it's surroundings. Studying them is pointless if you have already studied white dwarfs because they're just cold white dwarfs - nothing to see here.

So we can skip black dwarfs completely.

White dwarfs

A white dwarf can form from almost any star - that is, the vast majority of stars is the Milky Way will become white dwarfs. So these are "easy" to make and messing around with blue dwarfs as an intermediate stage is just pointless farting around. So we just grab any old main sequence star with a mass of no more than about 10 solar masses and fiddle with that to make a white dwarf, right ?

Wrong.

We've already found white dwarfs and why make one when there's already one made for you ?

So we can happily skip the tedious make-your-own-white dwarf step too.

So far, so trivial. :-)

Red Dwarfs

We've already got those so we can again skip the make-your-own stage. In fact we humans have one next door - Proxima Centauri. Maybe your aliens won't be so lucky, but they might even have one in the same system as they live in.

So we're skipping that stage too.

Leaving us with ...

Blue Dwarfs

These, as far as we know, do not yet exist.

To "make" one you need a red dwarf of greater than 0.25 solar masses and not more than 0.35 solar masses (the upper limit for red dwarfs). You also need to wait until the red dwarf fuses basically all the Hydrogen in it's core. Then it starts to burn other nuclei and that's when it becomes blue.

And to do this you just wait. A long time. A very long time - something on the order of about a trillion years (compare to the age of the Sun - just 4 billion years).

Alternative.

Start with a lot of helium - enough to make a blue dwarf core (I do not know how much that would be). Introduce it somewhere in "empty" space, ideally directing it towards a common central area.

Add hydrogen ("lots") in a similar way when the central area is reasonably concentrated (but before fusion starts). This should increase the rate of collapse and if you add enough of the right materials you will get a helium core surrounded by a hydrogen body - more or less a blue dwarf. Fusion should start "normally" from gravitational pressure and you can monitor the whole thing to your heart's content.

A few minor details.

To do any of this (including visit existing distant white dwarfs) you need FTL drives. If you can build FTL drives you then have only the "minor" difficultly of being able to transport enough material to make a small star (about 0.25 solar masses of the stuff) to your test site to make your blue dwarf.

The energy requirements for this would seem insane.

However, if you can do all these things then a couple of really difficult problems remain :

  • Getting planning permission (good luck because they'll complain about the color not being in keeping with the neighborhood)
  • Getting a grant from the science council (low odds, but it's sexy big science so maybe ...)
  • Legal objections from the environmentalists.

I'd consider the later one insurmountable.

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If you're talking about species capable of stellar manipulation, the "science-based" tag is probably a misnomer, because we're talking about technology so sophisticated it's tantamount to magic. That being said, if we're obeying the laws of physics...

Stellar Siphon

The best way to accelerate the progression from red, through blue, to white, is to exhaust the remaining hydrogen from the star. One way you could do that was employed on Stargate ("you blow up one star...") - you create a link through something like a wormhole to a black hole (or bring a portable one), and use that to drain the hydrogen before it even starts fusing. You'd probably get some wheat with the chaff if you were draining material from the dwarf, but it would speed things along, and there's likely to still be a lot of degenerate matter left.

alternately...

Fusion Accelerator

This one presumes the ability to manipulate gravity (might be impossible in our universe, so "science-based" is iffy).

Intensify the gravity of the red dwarf, increasing the rate at which hydrogen fuses. It'd get a lot brighter in the short term, but the old adage about the candle that burns twice as bright applies here.

This might present a problem in stage two...

Stellar Heat-Sink

White dwarfs aren't still fusing. Their luminescence is entirely due to residual thermal energy. So the solution is to cool down the star. Simple!

The problem is that you can't make a body in a vacuum radiate thermal energy faster than it's already doing so - there's a bunch of work on that topic. So you either have to build a megastructure that can be in direct contact with the star's surface and presents a larger radiative surface (problematic), or find some other way of cooling things down. Enter...

She Blinded Me With (Cryo)Science

So this one requires an enormous energy budget, but laser cooling might be your go-to. It's been done to objects as large as a gram. So it's just a matter of scaling it up. A lot. And having a large sink for the heat transfer. You would likely need nearly as much mass as you intended to cool to act as the sink.

Given the enormous amount of energy and effort required, unless there's a really good reason to speed things along - or unless your civilization has a source of energy that makes stars seem trivial - it might just be better to wait.

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