Pith. sign in

REVIEW 5 cited by

The Soft $\mathcal{S}$-Matrix in Gravity

Not yet reviewed by Pith; the record is open.

Re-run · record.json Download PDF Read on arXiv ↗

This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.

SPECIMEN: schema-true, not a live event

T0 review · schema-true

One-sentence machine reading of the paper's core claim.

pith:XXXXXXXX · record.json · timestamp

arxiv 2005.13433 v2 pith:LEEWBKET submitted 2020-05-27 hep-th

Elizabeth Himwich , Sruthi A. Narayanan , Monica Pate , Nisarga Paul , Andrew Strominger This is my paper
classification hep-th
keywords softcurrentgravitationalmathcalmatrixcutofffactorsupertranslations
verification ladder T0 review T1 audit T2 compute T3 formal
0 comments
abstract

The gravitational $\mathcal{S}$-matrix defined with an infrared (IR) cutoff factorizes into hard and soft factors. The soft factor is universal and contains all the IR and collinear divergences. Here we show, in a momentum space basis, that the intricate expression for the soft factor is fully reproduced by two boundary currents, which live on the celestial sphere. The first of these is the supertranslation current, which generates spacetime supertranslations. The second is its symplectic partner, the Goldstone current for spontaneously broken supertranslations. The current algebra has an off-diagonal level structure involving the gravitational cusp anomalous dimension and the logarithm of the IR cutoff. It is further shown that the gravitational memory effect is contained as an IR safe observable within the soft $\mathcal{S}$-matrix.

Discussion (0). Sign in to comment.

Forward citations

Cited by 5 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. An algebra of proper observables at null infinity: Dirac brackets, Memory and Goldstone probes

    hep-th 2026-05 unverdicted novelty 6.0 of 10

    The algebra of proper observables at null infinity admits Goldstone probes that measure the memory mode, but none can be built from shear or news alone, and the Dirac brackets acquire non-local corrections.

  2. An algebra of proper observables at null infinity: Dirac brackets, Memory and Goldstone probes

    hep-th 2026-05 unverdicted novelty 6.0 of 10

    Authors define proper observables and Goldstone probes on the Ashtekar-Streubel phase space at null infinity, showing supertranslation charges act correctly on shear and deriving distributional Dirac brackets with non...

  3. Localization and anomalous reference frames in gravity

    hep-th 2025-10 unverdicted novelty 6.0 of 10

    Constructs a phase space for gravitational degrees of freedom on null ray segments with commuting localized observables via edge modes and dressing time, then introduces an effective classical theory with Virasoro def...

  4. Effective density matrix for vacua in asymptotically flat gravity

    hep-th 2025-09 conditional novelty 5.0 of 10

    The vacuum of a large causal diamond in asymptotically flat gravity is claimed to be a Gaussian in the supertranslation Goldstone mode, giving modular Hamiltonian variance A/epsilon squared.

  5. Lectures on Carrollian Holography

    hep-th 2025-11 conditional novelty 3.0 of 10

    Massless scattering amplitudes, including gravitons, can be recast as correlators of a carrollian conformal field theory on null infinity, but the non-perturbative bootstrap program remains incomplete.

Pith tools