indifferent vs indifference

indifferent is not a noun while indifference is a noun.

Word	Noun	Adjective	Verb	Adverb
indifferent	No	Yes	No	No
indifference	Yes	No	No	No

indifferent (noun)	indifference (noun)
	the trait of lacking enthusiasm for or interest in things generally
	the trait of remaining calm and seeming not to care; a casual lack of concern
	unbiased impartial unconcern
	apathy demonstrated by an absence of emotional reactions

indifferent (adjective)	indifference (adjective)
(usually followed by `to') unwilling or refusing to pay heed
characterized by a lack of partiality
fairly poor to not very good
neither too great nor too little
being neither good nor bad
showing no care or concern in attitude or action
(often followed by `to') lacking importance; not mattering one way or the other
marked by a lack of interest
having only a limited ability to react chemically; chemically inactive
marked by no especial liking or dislike or preference for one thing over another