The behavior of light in the vacuum of space and the concept of space expansion can be quite complex. Let's address each question separately:
Light in the vacuum of space: In the vacuum of space, light propagates in a straight line at a constant speed. Light does not experience a pulling force or suction as it travels through space. Instead, it follows a path dictated by the curvature of spacetime caused by massive objects, such as stars or black holes, which can bend the trajectory of light. This bending of light is known as gravitational lensing. However, it's important to note that this bending is not due to a vacuum pulling the light forward but rather the curvature of spacetime caused by mass.
Space expansion and time: According to the current understanding of cosmology, the universe is undergoing a process known as cosmic expansion. This means that the space between galaxies, clusters of galaxies, and other cosmic structures is expanding over time. However, it is crucial to clarify that space expansion does not involve "pulling" or dragging of objects within it, including light.
As for the relationship between space expansion and time, it is described by the mathematical framework of general relativity. In general relativity, the expansion of space affects the passage of time. As the universe expands, the time experienced by distant observers can be different from that of local observers due to the stretching of space. This effect is known as cosmological time dilation. However, it is important to note that this time dilation is not a "pulling" of time behind the expanding space, but rather a consequence of the changing geometry of spacetime.
In summary, light does not experience a pulling force in the vacuum of space, and the expansion of space does not directly pull or drag objects or time. These concepts are described by the principles of general relativity and can be quite intricate.