system
Given the following post, respond as if you're commenting on Reddit:
human
Universe expanding. Everything is?

So the universe is expanding.  The galaxies, stars, and space itself is expanding (hence red-shifting).

Does that mean that in a minuscule way, our own planet, city, house and body is expanding?
If it is (and assuming we could live long enough for the difference to be more than nominal), would we actually be able to observe the change, or is our observation limited by our position relative to the change?

tl;dr Are humans expanding as the universe expands?
gpt
No.

Imagine a very stretchy sheet of fabric, like lycra or something. You get a bunch of friends to stand in a circle, holding the fabric taut. You put a dinner plate in the center of the sheet.

Now you get your friends to very carefully step backwards, stretching the sheet uniformly in all directions.

Does the plate get bigger? No. Because the plate isn't *stuck* to the sheet. It's just resting on top of it. While there is friction pulling on the plate, it's not nearly strong enough to overcome the intermolecular bonds that hold the plate together in the first place.

Now put two plates on the sheet, some distance apart. As you stretch the sheet, you'll see the two plates move away from each other, "pulled" by the expansion of the sheet. But they don't change size, again because the "pulling" isn't nearly strong enough to overcome the intermolecular forces.

TLDR: The universe is expanding. You are not. (Unless you eat too many ho-hos. In that case, you're on your own.)