White paper: 1-10 Hz matter-wave interferometer to test the spin entanglement witness for quantum gravity

Authors:Sougato Bose, Anupam Mazumdar, Marko Toroš, Tian Zhou, Tadeusz Adach, Niayesh Afshordi, Agya Sewara Alam, Alexandre Arbey, Navdeep Arya, Simon Baier, Peter F. Barker, Angelo Bassi, Ettore Bernardi, Lorenzo Braccini, Robert Brandenberger, Daniel Braun, Guri K. Buza, Luigi Cacciapuoti, Carlo Cepollaro, Lin-Qing Chen, Yanbei Chen, Ralph Jason Costales, Marion Cromb, Álvaro de la Cruz-Dombriz, Catalina Curceanu, Shubhang Dadhich, Debarshi Das, Saurya Das, Pratika Dayal, Subhadeep De, Ema Dimastrogiovanni, Lajos Diósi, Or Dobkowski, Kemal Döner, Brian D'Urso, Gurudev Dutt, Shafaq Gulzar Elahi, Samira Elghaayda, Matteo Fadel, Samuel Fedida, Omer Feldman, Fabiano Feleppa, Ron Folman, Joshua Foo, Paolo Fragolino, Laurent Freidel, Giulio Gasbarri, Marco Genovese, Andrew Geraci, Menachem Givon, Cisco Gooding, Jonathan M. H. Gosling, Piotr T. Grochowski, David Groswasser, Mustafa Gündoğan, Ekim Taylan Hanımeli, Bas Hensen, Dipankar Home, Richard Howl, Yonathan Japha, Maciej T. Jarema, Rainer Kaltenbaek, Adrian Kent, Eva Kilian-Rademacher, M. S. Kim, Jarosław K. Korbicz, Timothy Kovachy, Samuel Kováčik, Ohkyung Kwon, Gaetano Lambiase, Naor Levi, Iarley P. Lobo, Leon Loveridge, Adrian Lupascu, Paolo Luppi, Marta Maria Marchese, Antonino Marcianò, Aaron G. Markowitz, Chiara Marletto, Ryan J Marshman, J. D. D. Martin, Florian Millo, Gavin W. Morley, Maria Muretova, Sebastian Murk, Robin Oberfrank, Daniel K. L. Oi, Jerzy Paczos, Papadopoulos Stylianos, Matteo G. A. Paris, Mauro Paternostro, Alessandro Pesci, Luciano Petruzziello, Fabrizio Piacentini, Tanmay Kumar Poddar, Sofia Qvarfort, Markus Rademacher, Dennis Rätzel, Anna Chiara Rescigno, Ryan Rizaldy

et al. (21 additional authors not shown)

Abstract:In this white paper, we highlight the importance of the ($1-10~{\rm Hz}$) frequency range for laboratory tests of the quantum nature of gravity using the quantum gravity-induced entanglement of masses (QGEM) protocol. QGEM requires matter-wave interferometers with masses ($m\sim10^{-15}-10^{-14}~{\rm kg}$), brought within separations ($d\sim30-50~\mu{\rm m}$), while maintaining spatial superpositions of ($1-20~\mu{\rm m}$) and coherence for ($\tau\sim 0.1 - 1~{\rm s}$). These requirements make low-frequency environmental noise a central experimental challenge and place QGEM in a regime closely related to the low-frequency goals of the Einstein Telescope (ET) and the Cosmic Explorer (CE). In particular, QGEM is sensitive to relative acceleration noise (RAN) and to gravity-gradient noise (GGN) generated by seismic and other environmental mass-density fluctuations. For representative parameters $m=10^{-14}~{\rm kg}$, $\Delta x=10~\mu{\rm m}$, and $\tau=1~{\rm s}$, the differential acceleration-noise amplitude spectral density must be suppressed well below the $10^{-15}~{\rm m\,s^{-2}/\sqrt{Hz}}$ level to keep acceleration-induced dephasing below the relevant experimental scale. Achieving this level of low-frequency noise suppression is therefore a key requirement for QGEM and closely parallels the seismic and gravity-gradient noise challenges that ET and CE address.

arXiv:2610.07422 [quant-ph]

(or arXiv:2610.07422v1 [quant-ph] for this version)

https://doi.org/10.48550/arXiv.2610.07422 arXiv-issued DOI via DataCite (pending registration)