[ExI] Milky Way is on the outskirts of 'immeasurable heaven' supercluster

[BillK]

On Wed, Sep 3, 2014 at 10:10 PM, Anders Sandberg wrote:
<snip>
> So while we are in Laniakea right now, we will not always be. Unless we
> move. Or even better, move the galaxies closer together! I have been
> spending the afternoon estimating the mass-energy costs for large scale
> megascale engineering (on the K3 level): the relativistic rocket equation
> applies to galaxies too. There are some problems in estimating from how far
> away galaxies can be moved together (you need to move faster than the Hubble
> flow, but it is accelerating, so if you are too slow you will never reach
> the goal), but getting into the core of Laniakea should be fairly easy.
>

Wouldn't there be some small technical problems about moving galaxies?
You can't exactly tie a rope round a galaxy and drag it.

These structures are only gravitationally bound. When two galaxies
crash into each other, the light years space between suns ensures that
there are no dramatic explosions. The simulations seem to be like two
gases mixing, swirling around and eventually stabilizing.

Even if you could generate a force field large enough to contain a
galaxy and drag it, you then have the problem of maintaining the
internal structure, and not squashing all the suns together.
I don't think I'll quote for that job.

Moving the Earth to the best habitable zone as the Sun ages will keep
my company quite busy enough.

BillK