Star lifting

Star lifting involves building a Dyson swarm around a star which would extract and remove materials from a star's atmosphere and outer layers. One reason for doing this is to dramatically extend its lifespan and another is simply to gather materials. The simplest technique involves setting up a ring of current that generates a magnetic field that exerts forces on charged atoms in the star's atmosphere which has the effect of increasing the rate at which that star loses matter.

Starlifting the Sun
To starlift the Sun, a Dyson swarm of separate, individual ion accelerators could encircle the Sun. Materials from Mercury could be used to build and manufacture those satellites in space near the Sun. Solar panels attached to each one of these ion accelerators would provide power to them, allowing them to generate a magnetic field which would be used to accelerate charged particles (which is the current generated).

Each station would consist of solar power collectors which would receive about 20% of the Sun's solar flux. 50% of that energy could be used to power the ion accelerators. If 10% of the solar flux emitted by the Sun was used to uplift plasma from the Sun's surface, then 6.5 × 1018 tons of material could be removed from the Sun per year. At this rate, it would take 300 million years to remove the Sun's outer layers.

By removing the Sun's outer layers, its pressure and temperature would have decreased enough for nuclear fusion to stop occurring at its core. Thus, the Sun will have been converted into a white dwarf. The Sun would therefore no longer have an energy source and it would gradually radiate all of its remaining energy away as it cooled over the course of 2.3 trillion years. The conversion of the Sun from a main sequence star to a white dwarf would be a monumental achievement of human engineering because it would extend the duration of the habitability of the Earth from billions of years to trillions of years.

Gathering materials
After 300 million years of Sun lifting, a total of 2×1027 tons of mass could be extracted, the equivalent of over 300,000 Earths of mass. These could be used for the construction of megastructures such as Bishop rings, Bernal spheres, O'Neill cylinders, ring worlds, and other biospheres. Also, 4.8×1024 tons of new water could be manufactured using hydrogen atoms scooped from the Sun. This would be used to create active hydrospheres within megastructures or terraformed worlds within our solar system. The Sun-lifted hydrogen and helium could be stored, and finally the remaining 1.4% of material would be used to manufacture materials such as metals, oxides and plastics.

For each year of Sun lifting, we could build 1 billion square kilometers of new living area. After 300 million years of Sun lifting, we would have built 5.7×1017 square kilometers of new living area, equivalent to the total surface areas of a billion Earths. This would also comprise enough material to build a solid Dyson sphere. Finally, there are many methods to accelerate starlifting so that it doesn't take millions of years.