The Expanding Universe

[Play/Download Movie (0.5 MB)]

When describing the expanding Universe in the Big Bang model, we try to make analogies to raisins in baking bread. We also try to drop back to a two-dimensional Universe (although the trick there is to get the kids to understand that the Universe in the model is two-dimensional, and there is no "out of" or "above" the surface you've drawn). Pennies pasted to the surface of a rubber balloon is a common analogy for galaxies in a Universe.

This animation is that two-dimensional closed Universe. The Univeres is shown as a ball, with galaxies on it. The universe expands. The galaxies do not move across the face of the ball, but they do get farther apart. The galaxies do not grow as the Universe expands.

As with many of the movies I've put online, there is no narration or sound. It's designed to be used by a lecturer, who will pause it at opportune places to discuss it or ask questions of students.

This work is licensed under a Creative Commons License.

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