Which tense to use when presenting my master thesis? In a couple of weeks, I have to present my master thesis to both my professors (supervisors) and family and friends. After the title page, I immediately present the main novelty of my thesis (instead of first presenting a lot of "blablabla" about the literature and stuff). 

What would be a suitable tense to do this?

For instance: 


  I found/ have found/find that [description of findings]


or


  This thesis shows/has shown/showed that [description of findings]


I think you'll get the point. It is basically whether to use the present simple/ present perfect or past simple.

EDIT: My thesis is about the effects of unconventional monetary policy announcements by the Fed on European government bond markets. So w.r.t. to the comment of C26 below, it is something happened in the past. However, I also examined through which channels these announcements influence government bond markets in the eurozone. So this is more like a process; something that is most likely also true in the future (i.e. when these announcements will occur again).
I think it really depends on what the research shows. If the research demonstrates a process that is ongoing, or straddles multiple timelines/periods, you can go with "the research shows that". However, if it is related to something that happened squarely in the past, you can use the past only. 

I personally tend not to use the first person when discussing results of undertaken research, though I have seen it done in all the ways you describe. Really it comes down to what feels most natural and right to you as the author.