Experiments currently being undertaken at Stanford, and also by John Price, a physicist at the University of Colorado, will measure the force of gravity over a distance of less than a millimetre (the size of loop expected if there are only two extra gravity-swallowing dimensions).

ECONOMIST: A matter of gravity

Sinofsky explained that "you're in this loop" of ever increasing screen size, more battery to support it and, naturally, more weight.

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