How to deal with constant pressure given by advisor I am a third-year PhD student in mathematics from a very reputed institute in my country. I have one problem to share and discuss that is related with my guide. He is a senior professor in our department. The day I joined that institute he gave me one research problem and asked me to study about that and present. I did as much as I can and presented. In return, instead of appreciation I was being scolded for small mistakes. And it has continued for the last two years. Seniors say it is his way of working. I have lost my happiness. Sometime I cry for joining this course. My prof is not impressed with my good academic record and my hard work.

Second thing that worries me is that he is not much aware of my research problem. I feel like I know much more than him. He has no paper on that topic, although he has a good number of papers in other topics.  I never got help from him in solving research papers. I have to study papers on my own and then have to present to him.  And again for small mistake I have to suffer his taunts. I am scared whether I would be able to finish my degree in such an environment or not? Is this normal? Does every PhD student suffer such mental trauma? 

I need  advice. Thanks.
Every PhD student suffers mental trauma. You say your advisor "scolds" and "taunts" you. I think of scolding and taunting as personal attacks, and hence unacceptable. That said, your English makes me unsure if he is attacking you or your work. Attacking someones work is a common occurrence in academia. We tend to get one sentence notifications about our successes and pages and pages of feedback about our failures. Even the best researchers fail more often then they succeed. The key thing to remember is that, in general, it is not personal. You need to identify if your advisor is attacking you or your work.

You say your advisor "is not impressed with my good academic record and my hard work". Successful academics tend not to be impressed by academic records and hard work since it is par for the course. This doesn't mean they do not respect you. The best way to find out what your advisor thinks about you is to ask. Ask what you are doing well and what you can work on. Also say that you are feeling unsure of yourself and looking for reassurance. Some advisors will give you reassurance and a shoulder to cry on, others will simply tell you that you are not failing. Not failing is another word for a major success.