[SolarNet]

> Carter said it is "impossible" due to physics for it to stay open longer

At the beginning of the story it's implied that things like that are why Carter would be upset. Because the physics they had thought they had learned from the stargate hardware turned out to be software limitations instead. It's not like humans are ever capable of creating a wormhole to test for themselves.

[derefr]

Later on, when Carter gives a lecture on wormhole physics at an Air Force cadet academy, the teenage protagonist of that episode reacts in the same way, and Carter gives an "I thought that way once, but then I saw enough compelling evidence to change my mind about what's possible" speech.