I understand thermo dynamics; Ive been told halo used some type of neutrino radiation( neutrinos can pass through a full light year of lead at faster than light speed and may not even interact with the light year long solid block of lead they passed through) An yea i get about 0.00005% of the halo blasts or LESS actually hit their targets but; Halo ONLY DESTROYS life forms; The lost/missed radiation DOESNT count because unless it hits a life form IT DOESNT DO ANYTHING TO ANYTHING.