Yes, nature is not objective - it is relative. Mathematics is a discipline that is based around an objective framework. Lines and planes are mathematical constructs. Mathematics gives us an objective framework that can be used to model a natural world, but they are just models.
Some things are “line-like” or “plane-like,” in that modeling them as lines or planes is helpful to describe them. You can measure a distance “as the bird flies” because birds fly in lines compared to how humans travel along roads and paths. You can describe a dense, heavy, falling object as traveling in a straight line, because air resistance may be negligible over short distances.
A model is only useful insofar as it accurately represents reality. Lines and planes are mathematical constructs, and they may be incorporated into models that describe real things. “A beam of light crossing a room travels in a straight line” is probably a useful construct because the effects of gravity and refraction of the air are probably negligible for nearly all purposes. “The surface of a pond is a plane” is probably an acceptable model for a cartographer, since the height of ripples and the curvature of the earth are negligible at that scale.
The initial question was not “Do straight lines and flat planes model anything in nature,” but whether they exist in nature. They do not. They only exist in mathematics.
The curved light path is because a mathematical transform is done between two different frames of reference.
It’s no different than taking a mathematically straight line and performing a transform function to map it to a curved coordinate system. Because you allow transformation functions, there would also be no straight lines in math.
Yes, nature is not objective - it is relative. Mathematics is a discipline that is based around an objective framework. Lines and planes are mathematical constructs. Mathematics gives us an objective framework that can be used to model a natural world, but they are just models.
Some things are “line-like” or “plane-like,” in that modeling them as lines or planes is helpful to describe them. You can measure a distance “as the bird flies” because birds fly in lines compared to how humans travel along roads and paths. You can describe a dense, heavy, falling object as traveling in a straight line, because air resistance may be negligible over short distances.
A model is only useful insofar as it accurately represents reality. Lines and planes are mathematical constructs, and they may be incorporated into models that describe real things. “A beam of light crossing a room travels in a straight line” is probably a useful construct because the effects of gravity and refraction of the air are probably negligible for nearly all purposes. “The surface of a pond is a plane” is probably an acceptable model for a cartographer, since the height of ripples and the curvature of the earth are negligible at that scale.
The initial question was not “Do straight lines and flat planes model anything in nature,” but whether they exist in nature. They do not. They only exist in mathematics.
The curved light path is because a mathematical transform is done between two different frames of reference.
It’s no different than taking a mathematically straight line and performing a transform function to map it to a curved coordinate system. Because you allow transformation functions, there would also be no straight lines in math.