What about by network effects? Many less grains qualify as a heap by some threshold of heap-like behavior, by particulate physics, but otherwise isn't a heap.
A single grain can't interact with another grain, so it's not a heap. Two grains on a platform the size of one could slump, so maybe two make a heap:
What about by network effects? Many less grains qualify as a heap by some threshold of heap-like behavior, by particulate physics, but otherwise isn't a heap.
A single grain can't interact with another grain, so it's not a heap. Two grains on a platform the size of one could slump, so maybe two make a heap:
https://en.wikipedia.org/wiki/Angle_of_repose