Although it requires 2 contributors (rep $\geq2000$) to reject an edit, it only needs 1 by "rejecting and editing" actually. And later, I found this problem have been came up before.
Today I found some of my edits were rejected singlehandedly by "rejecting and editing" trivially, it's not they're rejected but they're not treated seriously that makes me disappointed. Edit 1-4 were rejected by the same user.
Edit 5: This question is about computing characterisctic class and not so relevant to string theory, so I added mathematical-physics and characteristic-classes, delete string-theory, but it was rejected and even wrongly edited. Calculate characterisctic class is apparently not a part of elementary physics and shouldn't tagged physics.
Edit 5 is partly my fault, since it does have strong background in string-theory, deleting it is not a good choice.
What can be done about this?
Any suggestions and opinions? Thank you for your kindly discussion.