Is the Speed of Light Bidirectional in an Expanding Universe?

[PeterDonis]

f gravitational fields are -conservative

They aren't in an expanding universe. More precisely, in an expanding universe, the concept of "gravitational field" is not well-defined.

 

[Tracer]

They aren't in an expanding universe. More precisely, in an expanding universe, the concept of "gravitational field" is not well-defined.

Thank you. Your comments have been noted.