Can modern science tell us the original source of energy?
Yes, It can.
All energy originates in the big bang 13.7 billion years ago.
How does the original source of energy for all living things on earth get converted to a usable form for living things?
How is the ultimate source of energy for heterotrophs the sun even though they cannot make their own food?
I have done some reading on this topic recently, and it seems that most experts in the field would agree that energy conservation is NOT valid on a large scale, i.e., in certain specific situations in General Relativity. This is because the conditions for Nöther's Theorem are not satisfied. Though I don't exactly understand how they are not satisfied, that's what leading cosmologists say.An alternative explanation is that the total energy of the Universe is…
The sun. Without the sun life on earth would soon stop because all available carbon (the basis of all life forms on Earth) would be used up. A few ecosystems get their energy partially or entirely from geothermal sources. The original source of this energy is radioactive decay heat from isotopes in the crust, mantle, and core. Both the sun and earth were formed from matter ejected and/or compressed by supernova explosions. So the original…