I think 'housing' is good. It suggests the Universe as a kind of container within which things can grow - like, an incubator, or a greenhouse.
'Housing' suggests a containing structure that surrounds something - like a house itself, or like other kinds of 'housing' - the housing of a computer, vacuum cleaner or other machine for example - the external structure, within which 'stuff gets done' - it describes the structure within which, processes may occur.
'To house' as a verb means to 'contain or shelter' - the latter being the sense of 'nurturing' I mentioned:
'Housing' is a perfectly correct word to use in your sentence.
'Holding', while being usable, and having the same meaning, is less evocative of the container of a process. It does however evoke hands, holding something, which can carry a meaning of 'caring', should you want that.
'Holding' also gives the feeling of particles milling around, but 'housing' has slightly more context of nurturing, or affecting the creation taking place.
'Holding' is not 'more correct' in this case, and it can be used in your sentence, but is perhaps less expressive than 'housing'.