Astronomers is Each Galaxy

Astronomers in Each Galaxy

and the fourth dimension

There are astronomers in each galaxy, and the light they see is also trapped on the curved surface of the hyper-sphere. As the sphere expands, the astronomer in any galaxy will think all the other galaxies are running away from him, and there are no privileged reference frames. The view that the universe looks by and large the same no matter from where we happen to view it was first proposed, so far as we know, by Giordano Bruno.

Well, the father away the galaxy, the faster its recession. The galaxies are embedded in, attached to space. And the fabric of space is expanding.

Horloge de la Tour. To the famous question – Where in the present universe did the Big Bang occur? – the answer is clearly, everywhere (quotations from Megan Jorgensen). Image © Elena

If there is insufficient matter to prevent the universe from expanding forever, it must have an open shape, curved like the saddle with a surface extending to infinity in our three-dimensional analogy. If there is enough matter, then it has a closed shape, curved like a sphere in our three-dimensional analogy. If the universe is closed, light is trapped within it.

Anyway, in such interdimensional contemplations, we need not be restricted to two dimensions. We can imagine a world of one dimension, were everyone is a line segment, or even the magical world of zero-dimensional beasts, the points. But perhaps more interesting is the question of higher dimensions…