The motion of a mechanical object, even a humansized object, should be governed by the rules of quantum mechanics. Coaxing them into a quantum state is, however, difficult because the thermal environment masks any quantum signature of the object’s motion. The thermal environment also masks the effects of proposed modifications of quantum mechanics at large mass scales. We prepared the centerofmass motion of a 10kilogram mechanical oscillator in a state with an average phonon occupation of 10.8. The reduction in temperature, from room temperature to 77 nanokelvin, is commensurate with an 11 ordersofmagnitude suppression of quantum backaction by feedback and a 13 ordersofmagnitude increase in the mass of an object prepared close to its motional ground state. Our approach will enable the possibility of probing gravity on massive quantum systems.
more » « less NSFPAR ID:
 10250626
 Author(s) / Creator(s):
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 Publisher / Repository:
 American Association for the Advancement of Science (AAAS)
 Date Published:
 Journal Name:
 Science
 Volume:
 372
 Issue:
 6548
 ISSN:
 00368075
 Page Range / eLocation ID:
 p. 13331336
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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