Well, the amount of energy that it would take to move a planet sized weapon from place to place is also in the range of the power of a sun. But at least the physics of the explosions were pretty close.
I do fear that the weapon sucking all of the energy of the sun off will just enable the debates about solar panels draining the sun’s energy. But what can I say, people are dumb.
Another problem, you cannot suck all of the energy of the sun without also absorbing the mass of the sun. If a sun is large enough to be in the range of a familiar yellow star then it would have a mass equivalent to the sun. Putting that much mass into the middle of an Earth sized planet would cause the gravitational field of the planet to grossly increase.
Some back of the envelope calculations, the mass of the sun is 333,000 times the mass of the Earth. The resulting conversion would be that the force of gravity would be obscene.
It is actually an easy conversion since the force of gravity calculation is
G (Gravitational constant) times Mass 1(You) times Mass 2 (Planet)
Distance to center of planet squared.
The only number that is changing in this calculation is the mass of the planet which is increasing by a factor of 333,000 times, meaning the pull of gravity would also increase by the same amount.
So your plucky hero Rey who weight what, 110 pounds, Finn and Han Solo kicking around at 180 pounds, and Chewy running about 300, they would now weigh…
Rey 18,000 TONS
Finn and Han 30,000 TONS
Chewy 50,000 TONS
They wold be crushed by their own weight.
Then we have the thing firing a blast of light and having it get somewhere in a reasonable amount of time, destroying the planet, and not getting diffracted or reflected EVERYWHERE ELSE IN THE UNIVERSE.
The speed of light is a constant. If you are moving past light speed you have to be either subspace (not visible) or you will take inordinately long periods of time to get from one planet to another.
For instance, if we fired a weapon from Earth aimed at our nearest neighbor it would take 4 years to get there. I was thinking of trying to calculate the amount to energy that would be lost, but that is dependent on a lot of factors and I would have to determine if it is a cold dense part of space, or a hot ionized portion of space to get within 7 orders of magnitude.
OK, anyway, this is just a start, next time I see the movie (Because I did enjoy it, even if it was largely the act 1 introduce characters portion of a trilogy), I will look for more things that need clarification.