@article{Gundhi2026,

title = {From equivalent Lagrangians to inequivalent open quantum system dynamics},

author = {Anirudh Gundhi and Oliviero Angeli and Angelo Bassi},

doi = {10.1103/4rpx-zj2x},

issn = {2643-1564},

year  = {2026},

date = {2026-02-06},

journal = {Phys. Rev. Research},

volume = {8},

number = {1},

publisher = {American Physical Society (APS)},

abstract = {<jats:p>Lagrangians can differ by a total derivative without altering the equations of motion, thus encoding the same physics. This is true both classically and quantum mechanically. We show, however, that in the context of open quantum systems, two Lagrangians that differ by a total derivative can lead to inequivalent reduced dynamics. While these Lagrangians are connected via unitary transformations at the level of the global system-plus-environment description, the equivalence breaks down after tracing out the environment. We argue that only those Lagrangians for which the canonical and mechanical momenta of the system coincide lead to operationally meaningful dynamics. Applying this insight to quantum electrodynamics (QED), we derive the master equation for bremsstrahlung due to an accelerated nonrelativistic electron upto second order in the interaction. The resulting reduced dynamics predicts decoherence in the position basis and closely matches the Caldeira-Leggett form, thus resolving previous discrepancies in the literature. Our findings have implications for both QED and gravitational decoherence, where similar ambiguities arise.</jats:p>},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2025,

title = {Measuring Decoherence Due to Quantum Vacuum Fluctuations},

author = {Anirudh Gundhi and Hendrik Ulbricht},

doi = {10.1103/s5c9-zjt9},

issn = {1079-7114},

journal = {Phys. Rev. Lett.},

volume = {135},

number = {2},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2024,

title = {Decoherence due to the Casimir effect?},

author = {Anirudh Gundhi},

doi = {10.1103/physrevd.110.116001},

issn = {2470-0029},

journal = {Phys. Rev. D},

volume = {110},

number = {11},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2023,

title = {Motion of an electron through vacuum fluctuations},

author = {Anirudh Gundhi and Angelo Bassi},

doi = {10.1103/physreva.107.062801},

issn = {2469-9934},

journal = {Phys. Rev. A},

volume = {107},

number = {6},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2021,

title = {Scalaron–Higgs inflation reloaded: Higgs-dependent scalaron mass and primordial black hole dark matter},

author = {Anirudh Gundhi and Christian F. Steinwachs},

doi = {10.1140/epjc/s10052-021-09225-2},

issn = {1434-6052},

journal = {Eur. Phys. J. C},

volume = {81},

number = {5},

publisher = {Springer Science and Business Media LLC},

abstract = {We propose an extension of the scalaron-Higgs model by a non-minimal coupling of the Standard Model Higgs boson to the quadratic Ricci scalar resulting in a Higgs-dependent scalaron mass. The model predicts a successful stage of effective single-field Starobinsky inflation. It features a multi-field amplification mechanism leading to a peak in the inflationary power spectrum at small wavelengths which enhances the production of primordial black holes. The extended scalaron-Higgs model unifies inflationary cosmology with elementary particle physics and explains the origin of cold dark matter in terms of primordial black holes without assuming any new particles.</jats:p>},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2021b,

title = {Primordial black hole dark matter in dilaton-extended two-field Starobinsky inflation},

author = {Anirudh Gundhi and Sergei V. Ketov and Christian F. Steinwachs},

doi = {10.1103/physrevd.103.083518},

issn = {2470-0029},

journal = {Phys. Rev. D},

volume = {103},

number = {8},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2021c,

title = {Impact of Dynamical Collapse Models on Inflationary Cosmology},

author = {A. Gundhi and J. L. Gaona-Reyes and Matteo Carlesso and A. Bassi},

doi = {10.1103/physrevlett.127.091302},

issn = {1079-7114},

journal = {Phys. Rev. Lett.},

volume = {127},

number = {9},

publisher = {American Physical Society (APS)},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{Gundhi2020,

title = {Scalaron-Higgs inflation},

author = {Anirudh Gundhi and Christian F. Steinwachs},

doi = {10.1016/j.nuclphysb.2020.114989},

issn = {0550-3213},

journal = {Nuclear Physics B},

volume = {954},

publisher = {Elsevier BV},

keywords = {},

pubstate = {published},

tppubtype = {article}

}