Sitting on a (very) extended object in space

[johne1618]

Hi,

I imagine a very long rigid rod in space with length L.

I assume that the center of mass of the rod will be at rest with respect to the Hubble flow - is that right?

If I travel to one of the ends of the rod will I now see nearby objects that are moving with the Hubble flow move past me parallel to the rod with a velocity v = H_0 L/2 where H_0 is the Hubble constant?

John

 

[Simon Bridge]

You can also do this by accelerating so the Hubble red-shift for some distant object is zero. Then it comes as no surprise that you are moving with respect to the objects around you.