Many of the free parameters of the theory have been constrained, from the coupling of the scalar field to the top field and via coupling to jets down to low coupling values with proton collisions at the ATLAS experiment.[5] and , are strongly constrained by the direct measurement of the speed of gravitational waves following GW170817.[6][7][8][9][10][11]
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^ATLAS Collaboration (2019-03-04). "Constraints on mediator-based dark matter and scalar dark energy models using TeV collision data collected by the ATLAS detector". Jhep. 05: 142. arXiv:1903.01400. doi:10.1007/JHEP05(2019)142. S2CID 119182921.
^Lombriser, Lucas; Taylor, Andy (2016-03-16). "Breaking a Dark Degeneracy with Gravitational Waves". Journal of Cosmology and Astroparticle Physics. 2016 (3): 031. arXiv:1509.08458. Bibcode:2016JCAP...03..031L. doi:10.1088/1475-7516/2016/03/031. ISSN 1475-7516. S2CID 73517974.
^Bettoni, Dario; Ezquiaga, Jose María; Hinterbichler, Kurt; Zumalacárregui, Miguel (2017-04-14). "Speed of Gravitational Waves and the Fate of Scalar-Tensor Gravity". Physical Review D. 95 (8): 084029. arXiv:1608.01982. Bibcode:2017PhRvD..95h4029B. doi:10.1103/PhysRevD.95.084029. ISSN 2470-0010. S2CID 119186001.
^Sakstein, Jeremy; Jain, Bhuvnesh (2017-10-16). "Implications of the Neutron Star Merger GW170817 for Cosmological Scalar-Tensor Theories". Physical Review Letters. 119 (25): 251303. arXiv:1710.05893. Bibcode:2017PhRvL.119y1303S. doi:10.1103/PhysRevLett.119.251303. PMID 29303345. S2CID 39068360.
^Ezquiaga, Jose María; Zumalacárregui, Miguel (2017-12-18). "Dark Energy After GW170817: Dead Ends and the Road Ahead". Physical Review Letters. 119 (25): 251304. arXiv:1710.05901. Bibcode:2017PhRvL.119y1304E. doi:10.1103/PhysRevLett.119.251304. PMID 29303304. S2CID 38618360.
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