不管： (a) not care. Ex: 我不管你是谁。你不能进来。→ I don't care who you are. You can't get in. (b) no matter. Ex: 不管我说什麽，他都不听。→ No matter what I say, he won't listen. (c) Literally, not deal with. But other possible English translations could be "not take care of" and "not pay attention to", and it has the idea of "letting sb have their own way". Ex: 据说 Brad Pitt 和 Angelina Jolie 现在都不管他们领养的小孩了。→ It's said that Brad Pitt and Angelina Jolie now just let their adopted children have their own way. 不在乎： can not care less; can't be bothered 不理： Literally, "not handle". But can be extended into "not respond" or "not get involved". Ex: 他正专心在看电视，门铃响了他也不理。→ He was focusing on watching TV and didn't respond to the door bell. Ex: 我不理你了。→ I'm done getting involved in your business. 无所谓： (a) not matter. Ex: 他想要救父亲的命，花再多的钱都无所谓。→ He wants to save his father's life and it doesn't matter if it's going to cost him. (b) be not the point; be not about sth. Ex: 我就是喜欢练身体，无所谓减不减肥的。→ I just like working out. Losing weight is not the point/It's not about losing weight. 我不管 = I don't care (what happened/what is happening/whatever trouble you'll/you'd go(ne) through). 我不管了 = I'm done dealing with/paying attention to it. 我不在乎 = I can't care less/don't give a shit. I can't be bothered. 我无所谓 = It doesn't matter to me.

不管+sth. 不在乎+sth./sb. 不理+sth./sb.(作 动词 用) 无所谓（eg.我无所谓。/这件事对我来说无所谓。） hehe.

我不在乎，无所谓==i don't care 我不管，不理≈i don't care,if someone say the two words,usually he/she is willful. maybe "ignore" can express these two more properly.

when people asked about your opinion for one thing, if you don't care, you use->我不管（i don't care），我不在乎。 when people say sth and you even don't want to react or talked about, you use->不理 无所谓, for me is more like "doesn't matter". i.e. What do you want to drink? Answer: 我无所谓，随便。（I don't mind, anything is ok.）

the meaning of these four words is similar. Usually we use them as we wish/ eg: 我才不管呢=我才不在乎呢=我才不理呢=我无所谓，but 不在乎is more similar to 无所谓,and 不管 is more similar to 不理·· hope it's helpful to you``