https://streetscience.com.au/the-power-of-the-sun/#:~:text=Well, the Sun produces about,consumes in an entire year!
the Sun produces about 3.8 x 10²⁶ joules of energy every second.
100,000 years are 3.1536e+12 s, now we do the calculation
(3.1536e+12 s/1 s)*3.8 x 10²⁶ joules= 1.198368e+39 Joules
This is the energy released by a neutron star in 0.1 s
Now let's calculate the energy released by a neutron star in 1 s
(1 s/0.1 s)* 1.198368e+39 Joules= 1.198368e+40 Joules
This is the energy released by a neutron star in 1 s
Then, this would be the energy released by a 20,000 neutron star, now let's calculate with the 2255 m one which is that of Nidavellir.
(2255 m/20000 m)* 1.198368e+40 Joules= 1.35115992e+39 Joules
SGR 1806-20
Furthermore, a Dyson sphere captures all the energy of a star and concentrates it in a single direction.
And the explosion was real
And it has to do with the fact that when Eitri tells Thor "you will receive all the strength of a star", he is not only referring to its luminosity, he is referring to all the energy it contains, and also the Dyson sphere is responsible for capturing all the energy of a star and concentrating it in a single direction.