What I see here is mostly fear to failure. Fear about "not keeping the high standard level that should define myself". Fear about being perceived as a mediocre

What I see here is mostly fear to failure. Fear about "not keeping the high standard level that should define myself". Fear about being perceived as a mediocre scientist saying incorrect things. This is wrong. Let me tell you a thing. Nobody will cares. Not-one-single people will care about your mind image. 1-Feeling depressed or having doubts in some point of the process of writing your thesis is more common than you think 2-Run, reset and try in a different field will not be easier, it will be more difficult. It always is. 3-Closures provide a lot of peace of mind. Finish your thesis and then move your mind to greener pastures. A not perfect thesis about a poor known theme, is better than none. So, just keep working and do your best effort. Most people never receive a Nobel in any case and what people could think about you, is not so relevant as you think. In the end, you will be the expert in quantum computing, not them. Remember also that any error slipped in your these can be fixed later. Science is not written in stone. We fall and we learn. Scientists are expected to commit honest mistakes.