Hello,

No you can't do that. Only Bsc in physics students can only  join Msc in physics. You have studied Btech then you can pursue Mtech in your branch only. You can't even choose other branch specialization. It has to be your branch or some way related to your branch. It has to have some or the other way connected to your domain.

In aboard, there is this facility that after graduation , any one can pursue masters in any domain but in India this facility is not provided.

If you belong to CSE/IT branch then you can pursue msc in Mathematics as you studied maths for 2 years and you have other papers which is corresponding to maths like optimization engineering. If you belong to chemical engineering branch then you can opt for Msc in Chemistry. This facility is provided only in IITs. If you are satisfying the criteria set by them then only you can join. No other institute provides it.

Hope it helps!