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REVIEW 3 major objections 5 minor 1 cited by

Localizing quantum fields with time-dependent potentials

T0 review · 3 major / 5 minor · reviewed 2026-08-09 · deepseek-v4-flash

Pith's one-line read Growing a cavity's walls adiabatically can localize quantum field modes while keeping them arbitrarily close to pure.

desk verdict Genuinely new numerical study of mode purity under adiabatic wall creation; the trend is believable, but unpublished smearing widths and sign typos keep the 'arbitrarily pure' claim from being fully supported. read the letter →

arxiv 2502.02643 v2 pith:AVGJ6D5B submitted 2025-02-04 quant-ph gr-qc

classification quant-phgr-qc MSC 81T1081P4081-08 PACS 03.70.+k03.67.-a
keywords quantumfieldtheorylocalizationtime-dependentpotentialstwo-pointfunctionsymplecticeigenvaluemixednessadiabaticapproximationentanglementharvesting
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

This paper asks whether a quantum field's degrees of freedom can be confined to a finite spatial region without becoming impractically mixed. It studies a massless scalar field in 1+1 dimensions, starting in the vacuum, with a smooth potential that grows linearly in time until it forms two cavity walls. Evolving the field's two-point function numerically, the authors track the symplectic eigenvalue of a localized mode's covariance matrix as a measure of purity. Their central finding is that if the walls are raised slowly enough, on a timescale $T \gtrsim E^{-1}$ for a mode of energy $E$, the added mixedness is negligible and the localized mode can be made arbitrarily close to pure. This matters because the Reeh-Schlieder theorem guarantees any localized mode is mixed, and that unavoidable mixedness has been claimed to block the use of relativistic field modes as probes in protocols like entanglement harvesting.

What carries the argument

The engine is the regularized two-point function $W(x,x')$ of the field, evolved as a hyperbolic initial-value problem on a finite domain with the time-dependent external potential $V(x,t)=V_{\mathrm{max}}(t/T)$ times two smoothed walls, with short-distance singularities tamed by Gaussian spacetime smearing of widths $\sigma_x$ and $\sigma_t$. From $W$ the paper builds the covariance matrix of the quadrature operators $\hat{Q}=\int dx\, f(x)\hat{\phi}(x)$ and $\hat{P}=\int dx\, g(x)\hat{\Pi}(x)$, and extracts the symplectic eigenvalue $\nu(t)=2\sqrt{\langle\hat{Q}^2\rangle\langle\hat{P}^2\rangle-\operatorname{Re}\langle\hat{Q}\hat{P}\rangle^2}$. The adiabatic claim is carried by the scaling $T\gtrsim E^{-1}$: as the wall-growth time exceeds the inverse mode frequency, the time-averaged $\nu$ tends to $1$ and its fluctuations decrease.

What would settle it

Re-run the same wall-growth protocol with $\sigma_x$ and $\sigma_t$ varied by an order of magnitude and with the outer cavity length $L$ doubled; if the time-averaged symplectic eigenvalue for mode $n=9$ no longer approaches $1$ at the same rate as $T$ grows, the claim of arbitrarily pure localized modes is a regularization- or box-size artifact.

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Extended reading notes

Core claim

Starting from the free-field vacuum, the authors dynamically raise a confining potential to $V_{\mathrm{max}}=250$ with wall sharpness and width chosen so the walls act as a good reflecting cavity. They isolate single modes of the resulting cavity using quadrature profiles $f(x)=g(x)=\sqrt{2/l}\,\sin(n\pi x/l)$, and track the symplectic eigenvalue $\nu(t)$ of the single-mode covariance matrix. Before the walls are raised, $\nu$ is slightly above $1$ because of the inevitable Reeh-Schlieder mixedness; during the growth it fluctuates at intervals of one light-crossing time; after the potential stops growing, its time average decreases monotonically toward $\nu=1$ as the growth time $T$ increases. For a mode of frequency $\omega_n$, the key scale is $T \gtrsim 1/\omega_n$, and the standard deviation of the fluctuations also shrinks as $T$ grows. The paper presents this as a proof of principle: localized modes of a quantum field can be made arbitrarily pure by adiabatically creating the cavity, so the Reeh-Schlieder obstruction is not a practical obstruction to using such modes as relativistic probes.

Load-bearing premise

The purity result depends on the unstated Gaussian smearing widths $\sigma_x$, $\sigma_t$ and on the finite computational box with Dirichlet walls being large enough; if either of these sets the value of the symplectic eigenvalue, the near-purity is an artifact of the numerical setup rather than a property of adiabatic wall growth.

Editorial extensions

If this is right

  • Localized modes of a quantum field can be prepared in nearly pure states by adiabatically growing the confining potential, making Reeh-Schlieder mixedness a controllable feature rather than a fundamental limitation.
  • Fully relativistic field-mode probes should not be dismissed as detectors for entanglement harvesting on grounds of unavoidable initial mixedness; slow wall growth removes one source of local noise.
  • The adiabaticity condition is mode-dependent: higher-frequency modes need shorter growth times, so the same wall-raising protocol purifies high-frequency modes first.
  • The two-point-function evolution method provides a convergent numerical tool for studying other time-dependent localization scenarios, including moving walls and the dynamical Casimir effect.
  • The regime of validity is quantified as $T\gtrsim E^{-1}$, so practical cavity creation can be planned around the mode frequencies of interest.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • I infer that the near-purity result would be much harder to achieve without some short-distance cutoff, because the vacuum entanglement that causes localized-mode mixedness is ultraviolet-dominated; the paper's unstated smearing widths are likely doing real work here.
  • A natural experimental test is a superconducting circuit or optical cavity where a tunable potential wall is ramped on a timescale long compared with the mode period; the predicted observable is a suppression of the mode's excess noise below the initial Reeh-Schlieder floor.
  • The authors' method suggests a practical recipe for choosing detector modes: select frequencies satisfying $T\gg 1/\omega$, then reduce residual mixedness further by local symplectic transformations, an optimization the paper leaves for future work.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 5 minor

Summary. The paper studies a massless scalar field in (1+1)-dimensional Minkowski spacetime, initially in the vacuum of a large Dirichlet box, and then applies a time-dependent external potential that grows linearly in time and mimics the creation of an effective cavity. The authors evolve the regularized two-point function with a second-order finite-difference scheme, verify spatial and temporal convergence, and use the evolved correlator to compute the energy density and the covariance matrix of localized quadrature modes. The main claim is that when the cavity walls are raised adiabatically (T ≳ E^{-1}), the time-averaged symplectic eigenvalue of a localized mode approaches unity, so dynamically localized field modes can be made arbitrarily pure. The paper connects this to the Reeh-Schlieder-based concern that localized field modes are inevitably mixed and hence poor probes for relativistic quantum information protocols.

Significance. If the quantitative claim survives scrutiny, this is a useful proof of principle: it shows that the mixedness introduced by dynamical localization is not an unavoidable obstruction for particle-detector models based on localized field modes. The computation has notable strengths: the main observable is not fitted to any target, the numerical method is tested for second-order convergence, and the qualitative adiabatic trends (higher modes purer, slower growth purer, fluctuations decreasing with T) are internally consistent and match physical expectations. The result directly addresses an ongoing debate about entanglement harvesting with field-based probes. The main weakness is that the central observable is ultraviolet-sensitive and is computed from a regularized correlator whose regulator parameters and finite-box independence are not documented; these omissions prevent the quantitative support for the headline claim from being reproducible as written.

major comments (3)
  1. [§IV.A, Eqs. (31)–(34)] The Gaussian smearing widths σ_x and σ_t are never stated, although the regularized two-point function (34) is the input to the covariance matrix (56)–(59) that produces every symplectic eigenvalue shown in Figs. 10–13. For a compactly supported mode of the massless vacuum, ⟨P̂²⟩ is sensitive to the short-distance singularity and can scale roughly as 1/σ², so ν is not a cutoff-independent number. Without reporting the values used and without a σ-scan at fixed mode, Vmax and T, the observed approach of ⟨ν⟩ to 1 cannot be distinguished from an artifact of the ultraviolet cutoff. Please report σ_x and σ_t and show that the T→∞ asymptote is insensitive to them over a range of values.
  2. [§III.B and §IV.B] The paper asserts that the computational box is 'large enough so that our results will not depend on the boundary condition' but provides no box-size scan. The Dirichlet boundaries at x=0,L and the distance from the potential walls to those boundaries act as an infrared regulator for the vacuum entanglement structure used to compute ν. Without varying L (or the wall positions relative to L) and showing that the averaged symplectic eigenvalue and the energy leakage curves are unchanged, the finite computational domain could itself be setting the scale that makes the localized modes appear pure. Please add such a scan.
  3. [§VI, Figs. 11–12] The central quantitative evidence for the adiabatic-purity claim is the monotone decrease of the time-averaged symplectic eigenvalue with T, but the averaging window is described inconsistently: the text before Fig. 11 says the average was taken over 'three times the light-crossing time', while footnote 5 says the average is over 'one light-crossing time'. The axes are also described only as 'scaled by the frequency of the n=9 mode' without giving the plotted variable explicitly. Please define the plotted quantity, the averaging window, and the exact post-growth time interval so the trend can be reproduced and checked.
minor comments (5)
  1. [§IV.B, Eq. (38)] The potential term on the right-hand side of Eq. (38) appears with an extra Δt² factor; after multiplying through by Δt², Eq. (40) has the correct form, so this appears to be a typo in Eq. (38) only.
  2. [§V.B and §VI] The symbol l is used for the cavity length in Eq. (65) while the potential width in Eq. (35) is written ℓ; the text also refers to 'l = 2.5 away from the edges' in a way that is confusing. Please define l explicitly (presumably xright − xleft) and distinguish it from ℓ throughout.
  3. [§VI, Eq. (61)] The last term should read Re{⟨Q̂(t)P̂(t)⟩} (or Re{⟨Q̂P̂⟩}) to match the definitions in Eqs. (57)–(59); as written the expression omits the expectation-value brackets.
  4. [Captions of Figs. 2 and 3] The captions state Δx = 0.05 with Nx = 100, which implies L = 5, inconsistent with the cavity walls at xright = 7.6 used elsewhere. Please give the actual box length and grid resolution used for the main simulations.
  5. [§VI, footnote 5] The use of ⟨A⟩ for a time average in footnote 5 conflicts with the standard expectation-value notation used throughout the rest of the paper; consider using an overline or an explicit time-average symbol instead.

Circularity Check

0 steps flagged · score 0.0 of 10

No circularity: the adiabatic-purity claim is a parameter-free numerical result, not a fit or a self-cited theorem.

full rationale

The central result, that adiabatically raising a confining potential leaves localized field modes nearly pure, is obtained by directly evolving the Gaussian-smeared two-point function (Eqs. (28)–(34)) and computing the symplectic eigenvalue ν(t) of the chosen quadrature modes via Eqs. (57)–(61). No parameter is fitted to the target quantity: the mode profiles f=g=√(2/l) sin(nπx/l) in Eq. (65) are fixed a priori as the approximate normal modes of the final Dirichlet cavity, and the wall-raising time T is scanned as an independent variable. The monotone decrease of ⟨ν⟩ with T shown in Fig. 11 is a computed dynamical trend that the authors explicitly compare to, rather than derive from, the adiabatic theorem; the theorem is an external benchmark, not an input. Self-citations ([27,28,30,31,33,55]) frame the detector-model context and the connection to entanglement harvesting, but the numerical derivation itself is self-contained and does not invoke any self-cited uniqueness or existence result as a load-bearing premise. The paper does not state the numerical values of the smearing widths σ_x and σ_t in Eqs. (31)–(33), and the symplectic eigenvalue is UV-sensitive, so the quantitative support is not fully reproducible; however, this is a parameter-reporting and correctness concern, not a circularity: the computed object is openly the smeared correlator, and the purity conclusion is not definitionally identical to any input. No step of the derivation reduces by construction to its own inputs, and no fitted parameter is relabeled as a prediction. Therefore there is no significant circularity.

Assumptions & free parameters 7 free parameters · 5 assumptions · 0 invented entities

The result rests on modeling choices rather than fitted constants: the hand-chosen potential parameters (V_max, β, ℓ), the unstated smearing widths (σ_x, σ_t), the final-cavity Dirichlet mode profiles, and the adiabatic extrapolation from the simulated T range. No new entities are introduced, and the Gaussian two-point function framework is standard. The most fragile inputs are the unstated regularization scale and the asserted but undemonstrated independence from the computational box.

free parameters (7)
  • V_max = 250
    Peak height of the confining potential (Eq. (35)). Chosen by hand; confinement quality and the baseline mixedness of the localized modes depend on it, and the paper does not scan V_max.
  • β (wall sharpness) = 30.0
    Sharpness of the potential walls (Eq. (35)); selected after the quality-factor scan in Fig. 6 as a 'suffices' choice (Sec. V.B).
  • ℓ (wall width) = 1.0
    Width of the potential walls (Eq. (35)); selected after the quality-factor scan in Fig. 7 (Sec. V.B).
  • smearing widths σ_x, σ_t = not stated
    Gaussian smearing widths in Eqs. (32)-(33) regularize the singular vacuum correlator; their values are never reported, yet the symplectic eigenvalue of a vacuum mode is UV-sensitive.
  • cavity geometry (x_L=3, x_R=7; xleft=2.4, xright=7.6; cavity length l) = l ambiguous (4 or 5.2)
    Wall positions and effective cavity length used in the mode profiles (65); the text gives different values for the potential maxima and the effective cavity boundaries, leaving l ambiguous.
  • computational box length L and grid resolution = not fully stated for main runs
    The domain is asserted large enough to be free-space-like (Sec. III.B), but no box-size scan is shown; grid parameters for the purity runs (Nx, Δx, Nt) are not given for Figs. 10-13.
  • mode number n for the adiabaticity scan = 9
    Chosen as a 'computational compromise' (Sec. VI); the generalization to other modes is asserted rather than demonstrated.
assumptions (5)
  • standard math The field state remains Gaussian under the quadratic time-dependent Hamiltonian, so the two-point function W(x,x') fully determines the purity of the localized modes.
    Used throughout Sec. VI to reduce purity to the symplectic eigenvalue of the single-mode covariance matrix (Eqs. (56)-(61)).
  • domain assumption The smeared two-point function (31)-(33) with Gaussian spacetime smearing is a faithful regulator of the singular vacuum correlator, and the specific σ_x, σ_t values do not affect the conclusions.
    Invoked in Sec. IV.A; the paper provides no σ-independence test, yet the purity numbers depend on the resolved UV entanglement.
  • domain assumption The finite computational domain with Dirichlet boundary conditions at x=0,L represents free space for the physics of interest (distance scales much smaller than L).
    Stated in Sec. III.B; no box-size convergence study is presented.
  • domain assumption The final confining potential behaves as a fully reflecting Dirichlet cavity, so the normal modes of the confined field are well approximated by sin(nπx/l) profiles (Eq. (65)).
    Stated in Sec. VI before Eq. (65); the paper notes the modes are 'not the exact normal modes for the local subregion'.
  • domain assumption The single-mode adiabatic theorem applies to the localized mode under the growing potential, so for T ≳ E^{-1} the mode reaches the instantaneous ground state of the final cavity.
    Invoked in Secs. V and VI to explain Figs. 11-13 and to extrapolate to 'arbitrarily pure' localized modes; the QFT/infinite-mode version is not proven in the paper.

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Cite this review

Pith. "Pith review of Localizing quantum fields with time-dependent potentials." pith.science (2026). https://pith.science/paper/AVGJ6D5B

@misc{pith2026250202643,
  author       = {Pith},
  title        = {Pith review of: Localizing quantum fields with time-dependent potentials},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/AVGJ6D5B}},
  note         = {Machine review of arXiv:2502.02643}
}
read the original abstract

In this paper we study the effect of localizing quantum field degrees of freedom by dynamically growing cavity walls through a time-dependent potential. We use our results to show that it is possible to do this without introducing non-negligible mixedness in localized modes of the field. We discuss how this addresses the concerns, raised in previous literature, that the high degree of entanglement of regular states in QFT may hinder relativistic quantum information protocols that make use of localized relativistic probes.

Figures

Figures reproduced from arXiv: 2502.02643 by the authors.

Figure 1
Figure 1. This plot shows the choice of confining potential for [PITH_FULL_IMAGE:figures/full_fig_p006_1.png] view at source ↗
Figure 2
Figure 2. The spatial convergence order of the real compo [PITH_FULL_IMAGE:figures/full_fig_p008_2.png] view at source ↗
Figure 3
Figure 3. The spatial convergence order of the imaginary [PITH_FULL_IMAGE:figures/full_fig_p008_3.png] view at source ↗
Figures from the paper (9 more)
Figure 5
Figure 5. Figure 5: Energy as a function of time in the interior of [PITH_FULL_IMAGE:figures/full_fig_p009_5.png]
Figure 4
Figure 4. Figure 4: Initial energy distribution of the localized [PITH_FULL_IMAGE:figures/full_fig_p009_4.png]
Figure 7
Figure 7. Figure 7: Quality factor of the confining potential as a func [PITH_FULL_IMAGE:figures/full_fig_p010_7.png]
Figure 6
Figure 6. Figure 6: Quality factor of the confining potential as a func [PITH_FULL_IMAGE:figures/full_fig_p010_6.png]
Figure 8
Figure 8. Figure 8: Energy density of the field during the time in which the cavity is being created. The blue curve is the energy density [PITH_FULL_IMAGE:figures/full_fig_p011_8.png]
Figure 9
Figure 9. Figure 9: Energy of the field inside and outside of the cavity, [PITH_FULL_IMAGE:figures/full_fig_p012_9.png]
Figure 10
Figure 10. Figure 10: Symplectic eigenvalue for the first five modes of [PITH_FULL_IMAGE:figures/full_fig_p013_10.png]
Figure 11
Figure 11. Figure 11: Average symplectic eigenvalue as a function of the [PITH_FULL_IMAGE:figures/full_fig_p014_11.png]
Figure 13
Figure 13. Figure 13: Probability of the n = 9 mode being in the ground state of the associated thermal Hamiltonian as a function of T. that as the cavity creation time T increases, the mode in question approaches the ground state. In summary, our results thus point to the fact that the ex…

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Reference graph

Works this paper leans on

69 extracted references · 64 canonical work pages · cited by 1 Pith paper

  1. [1]

    local noise

    pick a set of modes that represent physically accessi- ble modes inside the cavity, and 2) analyze the state of these modes after the cavity is created after tracing out everything else. Selecting a suitable profile for the quadratures requires some care. These profiles can be chosen, for example, by taking into account what are the actual degrees of free...

  2. [2]

    Haag, Local Quantum Physics: Fields, Particles, Al- gebras, 1st ed

    R. Haag, Local Quantum Physics: Fields, Particles, Al- gebras, 1st ed. (Springer Publishing Company, Incorpo- rated, 2012)

  3. [3]

    A. P. Balachandran, Localization in quantum field the- ory, Int. J. Geom. Methods Mod. Phys. 14, 1740008 (2017)

  4. [4]

    T. D. Newton and E. P. Wigner, Localized states for elementary systems, Rev. Mod. Phys. 21, 400 (1949)

  5. [5]

    A. S. Wightman, On the localizability of quantum me- chanical systems, Rev. Mod. Phys. 34, 845 (1962)

  6. [6]

    G. C. Hegerfeldt, Remark on causality and particle local- ization, Phys. Rev. D 10, 3320 (1974)

  7. [7]

    G. C. Hegerfeldt and S. N. M. Ruijsenaars, Remarks on causality, localization, and spreading of wave packets, Phys. Rev. D 22, 377 (1980)

  8. [8]

    Ruijsenaars, On Newton-Wigner localization and su- perluminal propagation speeds, Ann

    S. Ruijsenaars, On Newton-Wigner localization and su- perluminal propagation speeds, Ann. Phys. 137, 33 (1981)

Show all 69 references
  1. [9]

    D. B. Malament, In defense of dogma: Why there can- not be a relativistic quantum mechanics of (localizable) particles, in Perspectives on Quantum Reality: Non- Relativistic, Relativistic, and Field-Theoretic , edited by R. Clifton (Springer Netherlands, Dordrecht, 1996) pp. 1–10

  2. [10]

    R. D. Sorkin, Impossible measurements on quantum fields (1993), arXiv:gr-qc/9302018 [gr-qc]

  3. [11]

    Redhead, More ado about nothing, Found

    M. Redhead, More ado about nothing, Found. Phys. 25, 123 (1995)

  4. [12]

    Dowker, Useless qubits in ”relativistic quantum infor- mation” (2011), arXiv:1111.2308 [quant-ph]

    F. Dowker, Useless qubits in ”relativistic quantum infor- mation” (2011), arXiv:1111.2308 [quant-ph]

  5. [13]

    W. G. Unruh, Notes on black-hole evaporation, Phys. Rev. D 14, 870 (1976)

  6. [14]

    Candelas and D

    P. Candelas and D. W. Sciama, Irreversible thermody- namics of black holes, Phys. Rev. Lett. 38, 1372 (1977)

  7. [15]

    DeWitt, General Relativity; an Einstein Centenary Survey (Cambridge University Press, Cambridge, UK, 1980)

    B. DeWitt, General Relativity; an Einstein Centenary Survey (Cambridge University Press, Cambridge, UK, 1980)

  8. [16]

    Polo-G´ omez, L

    J. Polo-G´ omez, L. J. Garay, and E. Mart ´ ın-Mart ´ ınez, A detector-based measurement theory for quantum field theory, Phys. Rev. D 105, 065003 (2022)

  9. [17]

    Cliche and A

    M. Cliche and A. Kempf, Relativistic quantum channel of communication through field quanta, Phys. Rev. A81, 012330 (2010)

  10. [18]

    A. G. S. Landulfo, Nonperturbative approach to relativis- tic quantum communication channels, Phys. Rev. D 93, 104019 (2016)

  11. [19]

    Simidzija, A

    P. Simidzija, A. Ahmadzadegan, A. Kempf, and E. Mart ´ ın-Mart ´ ınez, Transmission of quantum informa- tion through quantum fields, Phys. Rev. D 101, 036014 (2020)

  12. [20]

    R. H. Jonsson, E. Mart ´ ın-Mart ´ ınez, and A. Kempf, In- formation transmission without energy exchange, Phys. Rev. Lett. 114, 110505 (2015)

  13. [21]

    Blasco, L

    A. Blasco, L. J. Garay, M. Mart ´ ın-Benito, and E. Mart ´ ın- Mart ´ ınez, Violation of the strong Huygen’s principle and timelike signals from the early universe, Phys. Rev. Lett. 114, 141103 (2015)

  14. [22]

    Tjoa, Quantum teleportation with relativistic commu- nication from first principles, Phys

    E. Tjoa, Quantum teleportation with relativistic commu- nication from first principles, Phys. Rev. A 106, 032432 (2022)

  15. [23]

    Pozas-Kerstjens and E

    A. Pozas-Kerstjens and E. Mart ´ ın-Mart ´ ınez, Harvesting correlations from the quantum vacuum, Phys. Rev. D92, 064042 (2015)

  16. [24]

    Pozas-Kerstjens and E

    A. Pozas-Kerstjens and E. Mart ´ ın-Mart ´ ınez, Entangle- ment harvesting from the electromagnetic vacuum with hydrogenlike atoms, Phys. Rev. D 94, 064074 (2016)

  17. [25]

    Lopp and E

    R. Lopp and E. Mart ´ ın-Mart ´ ınez, Quantum delocaliza- tion, gauge, and quantum optics: Light-matter interac- tion in relativistic quantum information, Phys. Rev. A 103, 013703 (2021)

  18. [26]

    Mart ´ ın-Mart ´ ınez, T

    E. Mart ´ ın-Mart ´ ınez, T. R. Perche, and B. d. S. L. Tor- res, Broken covariance of particle detector models in rela- tivistic quantum information, Phys. Rev. D 103, 025007 (2021)

  19. [27]

    de Ram´ on, M

    J. de Ram´ on, M. Papageorgiou, and E. Mart ´ ın-Mart ´ ınez, Relativistic causality in particle detector models: Faster- than-light signaling and impossible measurements, Phys. Rev. D 103, 085002 (2021)

  20. [28]

    C. J. Fewster and R. Verch, Quantum fields and local measurements (2018), arXiv:1810.06512 [math-ph]

  21. [29]

    C. J. Fewster and R. Verch, Measurement in quantum field theory, in Encyclopedia of Mathematical Physics (Second Edition), edited by R. Szabo and M. Bojowald (Academic Press, Oxford, 2025) second edition ed., pp. 335–345

  22. [30]

    Papageorgiou and D

    M. Papageorgiou and D. Fraser, Eliminating the ”impos- sible”: Recent progress on local measurement theory for quantum field theory (2023), arXiv:2307.08524 [quant- ph]

  23. [31]

    T. R. Perche, J. Polo-G´ omez, B. d. S. L. Torres, and E. Mart ´ ın-Mart ´ ınez, Particle detectors from localized quantum field theories, Phys. Rev. D109, 045013 (2024)

  24. [32]

    B. d. S. L. Torres, Particle detector models from path integrals of localized quantum fields, Phys. Rev. D 109, 065004 (2024)

  25. [33]

    M. H. Ruep, Weakly coupled local particle detectors can- not harvest entanglement, Class. Quantum Gravity 38, 195029 (2021)

  26. [34]

    Grimmer, B

    D. Grimmer, B. d. S. L. Torres, and E. Mart ´ ın-Mart ´ ınez, Measurements in QFT: Weakly coupled local particle de- tectors and entanglement harvesting, Phys. Rev. D 104, 085014 (2021)

  27. [35]

    Reeh and S

    H. Reeh and S. Schlieder, Bemerkungen zur unit¨ ar¨ aquiv- alenz von lorentzinvarianten feldern, Nuovo Cim. 22, 1051–1068 (1961)

  28. [36]

    Witten, APS medal for exceptional achievement in research: Invited article on entanglement properties of quantum field theory, Rev

    E. Witten, APS medal for exceptional achievement in research: Invited article on entanglement properties of quantum field theory, Rev. Mod. Phys. 90, 045003 (2018)

  29. [37]

    R. D. Sorkin, Expressing entropy globally in terms of (4d) field-correlations, J. Phys. Conf. Ser. 484, 012004 (2014)

  30. [38]

    R. D. Sorkin, From green function to quantum field, Int. 18 J. Geom. Methods Mod. Phys. 14, 1740007 (2017)

  31. [39]

    R. D. Sorkin and Y. K. Yazdi, Entanglement entropy in causal set theory, Class. Quantum Gravity 35, 074004 (2018)

  32. [40]

    N. D. Birrell and P. C. W. Davies, Quantum Fields in Curved Space, Cambridge Monographs on Mathematical Physics (Cambridge University Press, 1982)

  33. [41]

    R. M. Wald, Quantum Field Theory in Curved Space- time and Black Hole Thermodynamics (The University of Chicago Press, 1994)

  34. [42]

    Louko and A

    J. Louko and A. Satz, How often does the Unruh–DeWitt detector click? regularization by a spatial profile, Class. Quantum Gravity 23, 6321 (2006)

  35. [43]

    Mart ´ ın-Mart ´ ınez, Causality issues of particle detector models in QFT and quantum optics, Phys

    E. Mart ´ ın-Mart ´ ınez, Causality issues of particle detector models in QFT and quantum optics, Phys. Rev. D 92, 104019 (2015)

  36. [44]

    Tjoa and K

    E. Tjoa and K. Gallock-Yoshimura, Channel capacity of relativistic quantum communication with rapid interac- tion, Phys. Rev. D 105, 085011 (2022)

  37. [45]

    T. R. Perche and E. Mart ´ ın-Mart ´ ınez, Geometry of spacetime from quantum measurements, Phys. Rev. D 105, 066011 (2022)

  38. [46]

    B. A. Ju´ arez-Aubry, T. Miramontes, and D. Sudarsky, Semiclassical theories as initial value problems, J. Math. Phys. 61, 032301 (2020)

  39. [47]

    A. i. e. i. f. Zengino˘ glu and C. R. Galley, Caustic echoes from a schwarzschild black hole, Phys. Rev. D86, 064030 (2012)

  40. [48]

    Wardell, C

    B. Wardell, C. R. Galley, A. i. e. i. f. Zengino˘ glu, M. Casals, S. R. Dolan, and A. C. Ottewill, Self-force via Green functions and worldline integration, Phys. Rev. D 89, 084021 (2014)

  41. [49]

    K. E. Atkinson, An Introduction to Numerical Analysis (Wiley, 1991)

  42. [50]

    R. LeVeque, Finite Difference Methods for Ordinary and Partial Differential Equations: Steady-State and Time- Dependent Problems , Other Titles in Applied Mathe- matics (Society for Industrial and Applied Mathematics, 2007)

  43. [51]

    J. C. Strikwerda, Finite Difference Schemes and Partial Differential Equations, Second Edition , 2nd ed. (Society for Industrial and Applied Mathematics, 2004)

  44. [52]

    F. E. Hildebrand, Introduction to Numerical Analysis , 2nd ed. (McGraw-Hill, 1987)

  45. [53]

    S. M. Christensen, Vacuum expectation value of the stress tensor in an arbitrary curved background: The co- variant point-separation method, Phys. Rev. D 14, 2490 (1976)

  46. [54]

    S. M. Christensen, Regularization, renormalization, and covariant geodesic point separation, Phys. Rev. D17, 946 (1978)

  47. [55]

    E. G. Brown, E. Mart ´ ın-Mart ´ ınez, N. C. Menicucci, and R. B. Mann, Detectors for probing relativistic quantum physics beyond perturbation theory, Phys. Rev. D 87, 084062 (2013)

  48. [56]

    T. R. Perche, J. Polo-G´ omez, B. d. S. L. Torres, and E. Mart ´ ın-Mart ´ ınez, Fully relativistic entanglement har- vesting, Phys. Rev. D 109, 045018 (2024)

  49. [57]

    E. G. Brown and J. Louko, Smooth and sharp creation of a dirichlet wall in 1+1 quantum field theory: how singu- lar is the sharp creation limit?, Journal of High Energy Physics 2015, 61 (2015)

  50. [58]

    E. G. Brown, M. del Rey, H. Westman, J. Le´ on, and A. Dragan, What does it mean for half of an empty cavity to be full?, Phys. Rev. D 91, 016005 (2015)

  51. [59]

    M. E. Carrington, G. Kunstatter, J. Louko, and L. J. Zhou, Smooth and sharp creation of a spherical shell for a (3 + 1)-dimensional quantum field, Phys. Rev. D 98, 024035 (2018)

  52. [60]

    B. de S. L. Torres, K. Wurtz, J. Polo-G´ omez, and E. Mart ´ ın-Mart ´ ınez, Entanglement structure of quantum fields through local probes, J. High Energy Phys. 2023 (5), 58

  53. [61]

    G. T. Moore, Quantum theory of the electromagnetic field in a variable-length one-dimensional cavity, J. Math. Phys. 11, 2679 (1970)

  54. [62]

    Dodonov, A

    V. Dodonov, A. Klimov, and V. Man’ko, Generation of squeezed states in a resonator with a moving wall, Phys. Lett. A 149, 225 (1990)

  55. [63]

    D. A. R. Dalvit and F. D. Mazzitelli, Creation of photons in an oscillating cavity with two moving mirrors, Phys. Rev. A 59, 3049 (1999)

  56. [64]

    C. M. Wilson, G. Johansson, A. Pourkabirian, M. Simoen, J. R. Johansson, T. Duty, F. Nori, and P. Delsing, Observation of the dynamical casimir effect in a superconducting circuit, Nature 479, 376 (2011)

  57. [65]

    A. G. Mart ´ ın-Caro, G. Garc ´ ıa-Moreno, J. Olmedo, and J. M. S´ anchez Vel´ azquez, Classical and quantum field theory in a box with moving boundaries: A numerical study of the dynamical Casimir effect, Phys. Rev. D 110, 025007 (2024)

  58. [66]

    C. I. Velasco, N. F. Del Grosso, F. C. Lombardo, A. Soba, and P. I. Villar, Photon generation and entanglement in a double superconducting cavity, Phys. Rev. A106, 043701 (2022)

  59. [67]

    J. P. Louys Sans´ o, N. F. Del Grosso, F. C. Lombardo, and P. I. Villar, Superconducting quantum circuit to simulate the dynamical casimir effect in a double cavity, Phys. Rev. A 111, 013714 (2025)

  60. [68]

    Zenger, Sparse grids, in Notes on Numerical Fluid Me- chanics, edited by W

    C. Zenger, Sparse grids, in Notes on Numerical Fluid Me- chanics, edited by W. Hackbusch (Vieweg, Braunschweig, Wiesbaden, 1991) vol. 31 ed., pp. 241–251

  61. [69]

    Garcke, Sparse grids in a nutshell, in Sparse Grids and Applications , edited by J

    J. Garcke, Sparse grids in a nutshell, in Sparse Grids and Applications , edited by J. Garcke and M. Griebel (Springer Berlin Heidelberg, Berlin, Heidelberg, 2013) pp. 57–80

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