The hammer-feather drop in the world’s biggest vacuum chamber [video]

Re:The hammer-feather drop in the world’s biggest vacuum cha... by cryowaffle on Tuesday November 04, 2014 @10:04AM (#8556791)

Can someone explain to me the last part about the items standing still and no force acting on them? Isn't gravity acting on them, pulling the earth and items together?

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Re:The hammer-feather drop in the world’s biggest vacuum cha... by gradi3nt on Tuesday November 04, 2014 @10:10AM (#8556827)

Imagine being inside of a closed box like an elevator. Without leaving the box there is no way to tell the difference from being in free fall towards Earth versus floating in interstellar space. Therefor, general relativity take the perspective that gravity is a fictitious force (like centrifugal force) that arises from the shape of spacetime.

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Re:The hammer-feather drop in the world’s biggest vacuum cha... by josu on Tuesday November 04, 2014 @11:01AM (#8557182)

>versus floating in interstellar space

Versus being inside that an elevator that is being accelerated in interstellar space

This seems like a pretty good explanation: http://www.astronomynotes.com/relativity/s3.htm

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Re:The hammer-feather drop in the world’s biggest vacuum cha... by bweitzman on Tuesday November 04, 2014 @02:57PM (#8558710)

gradi3nt had it right

Free fall feels like floating Standing still (in the presence of the Earth's gravity) feels like being accelerated.

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