Personally, I think the repercussions would be GRAVE should the
world (or half the world plunges into darkness for 3 days.
Firstly, if lets say the entire world (planet Earth) plunges into
darkness, this would mean oour SUN wnet out! If the sun went out,
we will be in serious trouble - we'll all be doomed; because the
sun will not just simply stop shining - it will swell up many times
over it's own size before it IMPLODES. It's demise will mean our
demise....
Secondly, If our planet Earth plunges into darkness on one side,
that only means our planet stopped spinning! This is also rather
bad; the molten magma in our Earth's core, depends a lot on the
spinning of our planet to distribute itself evenly, striking a
balance, as well as generating the gravity and magnetic field
necessary to balance our environment. I say all hell will break
loose if we stop spinning - think of earthquakes, electric storms,
rising sea and ocean levels flooding cities, melting polar caps,
one side fried by the sun, the other side turning into ice...
Either scenarios, we DIE....