"We have showed that"/ "We have shown that" or "We showed that"?

Solution 1:

In the abstract to a scientific paper - at least in my field, statistics - you might use the simple present: "We show that ...".

In the discussion, the logic of using "we have shown..." is that you are referring to something in the past that stopped recently but has an influence on the present (which is this context is the present moment you are sharing with the reader of the paper).

If you said "we showed..." then the reader would expect that to refer to your previous paper, not to the one he is currently reading.

Solution 2:

As a native Irish-English speaker I'd say "We have shown". I'm not 100% of the legalities of why that is, but "We have showed" is just as hard to pronounce as "a apple".

If you're reading the paper back, it's much easier to read "have shown" than "have showed".

This might help with the technicality side of it.