the god linked the following.....
https://en.wikipedia.org/wiki/World_line said:
For example, the orbit of the Earth in space is approximately a circle, a three-dimensional (closed) curve in space: the Earth returns every year to the same point in space. However, it arrives there at a different (later) time. The world line of the Earth is helical in spacetime (a curve in a four-dimensional space) and does not return to the same point.
And such comments are not limited to wiki alone, just google it, there are various references available for curved / helix path. So it is not an easy task to get along with the definition of straightline in GR, purely on non-mathematical approach.
The point of debate and the first valid point you objected to was at post 4:
Everything moves through space in a straight line unless acted upon by a force.
you replied.......
This one needs rethinking on your part.......dig a bit deeper, you will know that, it is not the case.
That was followed by many examples from members including a mod re your actual intentions in the thread and moving the goal posts.
The following parrotized summary sums it up.......
Light follows geodesic paths in curved spacetime. That is well known.
We see that geodesical path as gravitational lensing.
The rotation of Earth and planets could also be said to be following geodesics in spacetime, explainable in simple Newtonian terms as a tussle between the pull of gravity by the parent star, and the straight line motion of the planet/Satellite.
The same could be said to apply to the motions of the stars around the galactic center: The stars try and maintain their straight line motion, while the pull of gravity from the SMBH at the center, keeps them in orbit.
Conversely they are simply following the same geodesic paths in curved spacetime as is light.
And a wiki link to trump your link.......
https://en.wikipedia.org/wiki/Geodesics_in_general_relativity
In
general relativity, a
geodesic generalizes the notion of a "straight line" to curved
spacetime. Importantly, the
world line of a particle free from all external, non-gravitational force, is a particular type of geodesic. In other words, a freely moving or falling particle always moves along a geodesic.
In general relativity, gravity can be regarded as not a force but a consequence of a curved spacetime geometry where the source of curvature is the
stress–energy tensor(representing matter, for instance). Thus, for example, the path of a planet orbiting around a star is the projection of a geodesic of the curved 4-D spacetime geometry around the star onto 3-D space.
Here's another that I already supplied....
http://mathworld.wolfram.com/Geodesic.html
A geodesic is a locally length-minimizing curve. Equivalently, it is a path that a particle which is not accelerating would follow. In the plane, the geodesics are straight lines. On the sphere, the geodesics are great circles (like the equator). The geodesics in a space depend on the Riemannian metric, which affects the notions of distance and acceleration.