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Title: Interferometric constraints on quantum geometrical shear noise correlations

Final measurements and analysis are reported from the first-generation Holometer, the first instrument capable of measuring correlated variations in space-time position at strain noise power spectral densities smaller than a Planck time. The apparatus consists of two co-located, but independent and isolated, 40 m power-recycled Michelson interferometers, whose outputs are cross-correlated to 25 MHz. The data are sensitive to correlations of differential position across the apparatus over a broad band of frequencies up to and exceeding the inverse light crossing time, 7.6 MHz. By measuring with Planck precision the correlation of position variations at spacelike separations, the Holometer searches for faint, irreducible correlated position noise backgrounds predicted by some models of quantum space-time geometry. The first-generation optical layout is sensitive to quantum geometrical noise correlations with shear symmetry---those that can be interpreted as a fundamental noncommutativity of space-time position in orthogonal directions. General experimental constraints are placed on parameters of a set of models of spatial shear noise correlations, with a sensitivity that exceeds the Planck-scale holographic information bound on position states by a large factor. Furthermore, this result significantly extends the upper limits placed on models of directional noncommutativity by currently operating gravitational wave observatories.
 [1] ;  [1] ;  [2] ;  [3] ;  [4] ; ORCiD logo [5] ;  [6] ;  [6] ;  [7] ; ORCiD logo [8] ;  [1] ;  [1] ;  [6]
  1. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
  2. Univ. of Michigan, Ann Arbor, MI (United States)
  3. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Univ. of Chicago, Chicago, IL (United States)
  4. California Inst. of Technology (CalTech), Pasadena, CA (United States)
  5. Univ. of Chicago, Chicago, IL (United States); Korea Advanced Institute of Science and Technology, Daejeon (Republic of Korea)
  6. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
  7. Univ. of Chicago, Chicago, IL (United States)
  8. Univ. of Michigan, Ann Arbor, MI (United States); Univ. of Chicago, Chicago, IL (United States)
Publication Date:
Report Number(s):
FERMILAB-PUB-16-527; arXiv:1703.08503
Journal ID: ISSN 0264-9381; 1519160
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Classical and Quantum Gravity
Additional Journal Information:
Journal Volume: 34; Journal Issue: 16; Journal ID: ISSN 0264-9381
IOP Publishing
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
Country of Publication:
United States
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; interferometry; laser interferometers; spectral responses; spectral coherence
OSTI Identifier: