go under vs go by

go under and go by both are verbs.

Word	Noun	Adjective	Verb	Adverb
go under	No	No	Yes	No
go by	No	No	Yes	No

As verbs, go under and go by are synonyms defined as:

go under (verb)	go by (verb)
be called; go by a certain name	be or act in accordance with
go under	be called; go by a certain name
disappear beyond the horizon	for time to move forward
	move past