Originally Posted by ZrByte

There will actually be 3 time machines.
The original timeline
The Alternate timeline
and the new timeline

That is unless they destroyed the other 2 timemachines in the past.

Also if timetravel worked like startrek then the original Daniel never would have been there to interact with the alternate timeline Carter O'Niell and Teal'c.

I think Timetravel works under the alternate reality principle. All timelines exist simultaniously but changes made in the current timeline cause the current reality to Merge with an existing realities timeline, or something like that .