I’ve just re-read The Buddhist Teaching on Physical Phenomena” book by Nina Van Gorkom.
“Rūpas outside the body are only produced by temperature, not by kamma, citta or nutrition.*” -xii or pg14 pdf.
Exactly what kinds of rūpa is meant here? Any kind or is it limited to something, such as “only naturally produced by insentient matter”?
If any kind of rūpa is meant, then there is a difficulty:
When a person builds something (lets say a house), that external thing (rūpa) was produced due to kamma and citta of the well fed person who built it. It wasn’t just due to “temperature” (I think that there should be a better translation of that word).
In physics terms, temperature means energy conservation. Matter being able to be created via kamma and mind is basically violation of energy conservation law.
Since I don’t think there’s a detailed measurement of the human body to account for all matters in it to see if it obeys energy conservation, the Buddhist claim still can fit in light of current scientific data.
In terms of building houses and so on, it’s not like magically the brick appear out of nothing, not just thin air, but nothing at all. Since it’s not the case, the matter of the house is merely rearranged by humans. Not created.