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Season 8 Episode 24 | 15m 22s
| Video has closed captioning.
What is Quintessence? Well we know that something is up with the way the universe is expanding - there’s some kind of anti-gravitational effect that’s causing the expansion to accelerate. We don’t know what it is - just that it competes against the inward-pulling effect of gravity. We call this mysterious influence dark energy. But, what is dark energy, really?