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> Let's suppose observations instead showed them to be moving toward one another. Would you then ask what started them doing that? No, because if I mentally re
by phaemon 13y ago
> Let's suppose observations instead showed them to be moving toward one another. Would you then ask what started them doing that?
No, because if I mentally rewind that tape back, I see things far apart now being pulled together. I know gravity pulls things together. Therefore it's reasonable to assume it's gravity pulling them together. I assume galaxies in the past were further apart and are now getting closer.
In the current scenario: I mentally rewind the galaxies moving apart, I see them being together and then moving apart. I don't have anything to explain this. Why did they move apart when they should have been pulled even closer together?
- fargolime 13y agoI see your point. But I wouldn't accept that space itself must expand to move them apart in the current scenario, since that leads to the flatness problem and also creates a new problem as to what causes space itself to expand. It would be cleaner to reject the expanding space idea, letting the flatness problem vanish, and then assume that some other unknown physical phenomenon moved the galaxies apart. The expanding space idea also leads to the horizon problem and the dark energy mystery, the blog shows.