URL: https://physikseminar.desy.de/hamburg/colloquia_in_2025/8_july_2025/@@siteview
Breadcrumb Navigation
No tests of Locality via Bell’s Inequality nor of Entanglement at Colliders
Herbi Dreiner (Universität Bonn)
Auditorium (Bldg 5, DESY Hamburg) and Zoom, 16:00h
Recently there has been an increased interest in possible tests of locality via Bell's inequality or tests of entanglement at colliders, in particular at the LHC. These have involved various physical processes, such as tt-production, τ+ τ− production, or the decay of a Higgs boson to 2 vector bosons H→VV. Meson anti-meson oscillations (e.g. B0−B0) have also been reconsidered at Belle II. We first review Bell’s original argument. Then discuss a response we formulated in 1991. We then argue here that none of these recent proposals constitute a test of locality via Bell's inequality or a test of quantum entanglement, including the Nature paper by Atlas. The reason is quite simple. In all cases what is measured are the momenta of the final state particles and all components of momenta commute. It is straightforward to construct a local hidden variable theory (LHVT) which exactly reproduces the data. This LHVT satisfies Bell's inequality and is by construction not entangled. Thus a test of locality via Bell's inequality or a test of entanglement is inherently not possible.
We invite you to attend the presentation in person at the DESY Auditorium. We will also offer a webcast for this colloquium.
Connection details at https://desy.zoom.us/j/99616528733
Meeting ID: 996 1652 8733
Meeting Password: 733220
