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Umm, no. When you blow up a balloon, the volume of rubber remains the same, but the area gets larger-- because it expands into open space. When the universe e
by michael_dorfman 17y ago
Umm, no.
When you blow up a balloon, the volume of rubber remains the same, but the area gets larger-- because it expands into open space.
When the universe expands, the volume of matter remains the same, but the area.....um, what? Expands into open space? That can't be right.
So, if the universe is getting larger, like a balloon, where is it going?
Oh, so it's not really like a balloon, then.
- ErrantX 17y ago> When you blow up a balloon, the volume of rubber remains the same, but the area gets larger-- because it expands into open space. Well, actually you're considering the air there - so it doesn't work. Ignore the air and think about how the balloon skin moves through the medium. In fact the balloon can be considered as not expanding into open air; simply more air is inside it than before - equally a little less air is outside it than there was before (ignoring pressure differences for the moment). Imagine if the skin was perfectly flat and was stretched. The air "moves" around it but is irrelevant to the expansion (and thinning) of the skin. The example only demonstrates how an object can have a larger area without changing volume. Same principle - but in the balloon it is easier to demonstrate relative movement. Im only basing this on my own experience but anyone I've ever given the proper explanation too has gone "oh yeh, I see" (or something the that effect).
- stcredzero 17y agoSo, if the universe is getting larger, like a balloon, where is it going? In a way, it's like all of the light waves are shrinking locally, and only the ones traveling the distance between galaxies are staying the same. (Which is not what's really happening either.)