An atom generates an electromagnetic field and so an atom creates three dimensional space (a magnetic field is a three dimensional field). An atom must obey the laws of the universe, and an atom cannot possess energy in a density that would violate the restrictions imposed upon the atom by the spatial gradient created by an atom. You can only have so much energy present in so much space, for space and energy are tightly intertwined (it would seem that you probably cannot have space without having energy present).

Hot gas is energetic gas. We also say that ‘hot gas expands’. The space an atom occupies must expand when the energy level of that atom increases. Only so much energy can be present in a given three dimensional space, and so therefore ‘hot gases must expand’, for expansion is the only allowable energy state. The density must decrease, and this requires expansion. The atom can expand by generating a stronger field, or the atom can expand by rising upwards in the surrounding spatial gradient so as to exploit gravitaional space dilation and so expand by rising towards less dilated space.

We can assume that the field surrounding the atom expands, and so hot gas atoms must increase the distance between atoms for you can only have so many hot gas atoms within the space external to the space of those atoms. The density of the energy field represented by those hot gas atoms must decrease and this means that the distance between hot gas atoms must increase. Hot gas atoms must displace other atoms so that the density restriction imposed upon energy by space is not violated..

From this behavior we can derive the following principle – the direction of movement of any closed energy system within a spatial gradient is always towards the allowable energy state (the correct density) and always away from the disallowed energy state (incorrect density).