Sandcastles in the air
It seems ubiquitous at beaches for children to build sandcastles. Is this behaviour global? Is it innate or learned? Did the children of nomadic, hunter-gatherer groups also build mounds in the sand?
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Getting sucked in
How close would one have to be to the coalescing black holes recently detected by LIGO to actually feel the gravitational waves without the aid of instruments? (Continued)
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Ever decreasing circles
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Dead of night
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Pale rider
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Getting sucked in
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