For example, if machines continue to grow exponentially in speed and sophistication, they will one day be able to decode the staggering complexity of the living world, from its atoms and molecules all the way up to entire planetary biomes. Presumably life doesn’t have to be made of atoms and molecules, but could be assembled from any set of building blocks with the requisite complexity. If so, a civilization could then transcribe itself and its entire physical realm into new forms. Indeed, perhaps our universe is one of the new forms into which some other civilization transcribed its world.[...]
For example, only about 5 percent of the mass-energy of the universe consists of ordinary matter: the protons, neutrons, and electrons that we’re composed of. A much larger 27 percent is thought to be unseen, still mysterious stuff. Astronomical evidence for this dark, gravitating matter is convincing, albeit still not without question. Vast halos of dark matter seem to lurk around galaxies, providing mass that helps hold things together via gravity. On even larger scales, the web-like topography traced by luminous gas and stars also hints at unseen mass. [...]
The universe does other funky and unexpected stuff. Notably, it began to expand at an accelerated rate about 5 billion years ago. This acceleration is conventionally chalked up to dark energy. But cosmologists don’t know why the cosmic acceleration began when it did. In fact, one explanation with a modicum of traction is that the timing has to do with life—an anthropic argument. The dark energy didn’t become significant until enough time had gone by for life to take hold on Earth. For many cosmologists, that means our universe must be part of a vast multiverse where the strength of dark energy varies from place to place. We live in one of the places suitable for life like us. Elsewhere, dark energy is stronger and blows the universe apart too quickly for cosmic structures to form and life to take root.
But perhaps there is another reason for the timing coincidence: that dark energy is related to the activities of living things. After all, any very early life in the universe would have already experienced 8 billion years of evolutionary time by the time expansion began to accelerate. It’s a stretch, but maybe there’s something about life itself that affects the cosmos, or maybe those well-evolved denizens decided to tinker with the expansion.
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