Hello,

After completing your BTech, you can take the JAM or JEST physics examinations. After passing JAM, you can apply for an MSc at IIT. You will be eligible for interviews for integrated PhD programmes in research institutes if you pass JEST.

These examinations can also be used to apply for integrated PhD programmes in IISERs.

After completing BTech, many people have gone on to become great theoretical physicists.

It is a myth that Engineers cannot become physicists. All you need is a passion for the topic and the willingness to put in the effort to master higher maths.

Hope it helped

All the best