Papers
Topics
Authors
Recent
Search
2000 character limit reached

Rational Analytic Syntomification in p-adic Cohomology

Updated 5 July 2026
  • Rational analytic syntomification is a p-adic geometric construction that replaces traditional analytic objects with stacks encoding prismatic, Nygaard-filtered, and syntomic data.
  • It employs pushouts and coequalizers to glue de Rham and Hodge–Tate realizations, enabling the recovery of syntomic complexes and related cohomological structures.
  • The framework bridges p-adic geometry with crystalline local systems and admissible filtered F‑isocrystals, providing insights into duality, Chern class formalism, and vector bundle correspondences.

Rational analytic syntomification is a pp-adic geometric construction in which a rigid-analytic or formal object is replaced by a stack XSynX^{\mathrm{Syn}} whose quasicoherent or perfect complexes encode syntomic, de Rham, Hodge–Tate, Hyodo–Kato, and étale data in a single framework. For a partially proper rigid-analytic variety XX over Qp\mathbb{Q}_p, the rational analytic syntomification XSynX^{\mathrm{Syn}} is built from the rational analytic prismatisation $X^\Prism$ and its Nygaard-filtered refinement XNX^N, and rational analytic syntomic cohomology is defined by

RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).

For a smooth pp-adic formal scheme X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K, a closely related syntomic stack XSynX^{\mathrm{Syn}}0 is defined as a pushout of the Nygaard-filtered prismatization along de Rham and Hodge–Tate comparison maps (Hauck, 16 Apr 2026, Pentland, 19 Oct 2025).

1. Definition and terminological scope

Two explicit constructions underlie the current meaning of syntomification. In the formal XSynX^{\mathrm{Syn}}1-adic setting, the syntomic stack XSynX^{\mathrm{Syn}}2 is defined as the pushout of XSynX^{\mathrm{Syn}}3 along two copies of XSynX^{\mathrm{Syn}}4, via the maps XSynX^{\mathrm{Syn}}5 and XSynX^{\mathrm{Syn}}6; equivalently,

XSynX^{\mathrm{Syn}}7

In the rigid-analytic setting, the rational analytic syntomification is defined as the coequalizer

XSynX^{\mathrm{Syn}}8

where the two arrows are the embeddings XSynX^{\mathrm{Syn}}9 (Pentland, 19 Oct 2025, Hauck, 16 Apr 2026).

Setting Basic construction Structural role
Smooth XX0-adic formal scheme XX1 Pushout defining XX2 from XX3 and XX4 Geometrizes syntomic cohomology and XX5-gauges
Partially proper rigid-analytic XX6 Coequalizer XX7 Produces rational analytic syntomic cohomology

In the rigid-analytic theory, “rational” refers to working after inverting XX8, with coefficients in XX9, and “analytic” refers to rigid-analytic, Berkovich, and Gelfand-stack geometry. In the formal theory, syntomification is the stack-theoretic operation that adds syntomic structure to prismatic and Nygaard-filtered data, so that derived global sections recover syntomic complexes (Hauck, 16 Apr 2026, Pentland, 19 Oct 2025).

2. Prismatisation, Nygaardification, and the gluing mechanism

The rigid-analytic construction begins from the rational analytic prismatisation Qp\mathbb{Q}_p0. For a totally disconnected nilperfectoid Gelfand ring Qp\mathbb{Q}_p1, one has a derived Berkovich space Qp\mathbb{Q}_p2 with Frobenius

Qp\mathbb{Q}_p3

a map Qp\mathbb{Q}_p4, and a radius map

Qp\mathbb{Q}_p5

A degree-Qp\mathbb{Q}_p6 Cartier divisor Qp\mathbb{Q}_p7 determines the prismatisation of the base, and Qp\mathbb{Q}_p8 is obtained by taking morphisms Qp\mathbb{Q}_p9. The de Rham stack satisfies

XSynX^{\mathrm{Syn}}0

and XSynX^{\mathrm{Syn}}1 inherits both a radius map XSynX^{\mathrm{Syn}}2 and a Frobenius XSynX^{\mathrm{Syn}}3 with XSynX^{\mathrm{Syn}}4 (Hauck, 16 Apr 2026).

Nygaardification introduces filtered structure. The base XSynX^{\mathrm{Syn}}5 is defined by a pullback involving XSynX^{\mathrm{Syn}}6, the overconvergent closed unit disk, and its de Rham stack. For XSynX^{\mathrm{Syn}}7, the Nygaardification XSynX^{\mathrm{Syn}}8 is defined using a XSynX^{\mathrm{Syn}}9-nilpotent thickening $X^\Prism$0 of the degree-$X^\Prism$1 divisor $X^\Prism$2, and

$X^\Prism$3

There is a natural projection

$X^\Prism$4

and two distinguished embeddings of $X^\Prism$5 into $X^\Prism$6.

The first embedding is the de Rham copy: $X^\Prism$7 arising from the locus $X^\Prism$8, where $X^\Prism$9. The second embedding is the Hodge–Tate copy: XNX^N0 arising from the locus XNX^N1, and it satisfies

XNX^N2

Away from the de Rham and Hodge–Tate loci, the Nygaardification is explicitly a cylinder: XNX^N3 This identifies XNX^N4 with the endpoint XNX^N5 and XNX^N6 with the Frobenius-twisted endpoint XNX^N7. The syntomification XNX^N8 is then the stack obtained by identifying these two copies of XNX^N9 inside RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).0 (Hauck, 16 Apr 2026).

The formal-stack construction exhibits the same pattern in a different language. There, RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).1 is the pushout of RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).2 along two maps from RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).3, and the resulting exact triangle

RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).4

recovers syntomic complexes such as RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).5 (Pentland, 19 Oct 2025).

3. Cohomology, duality, and Chern classes

The basic coefficient object on RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).6 is the Breuil–Kisin twist RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).7. On RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).8 it refines the pullback of the corresponding line bundle from RΓSyn(X,Qp(i)):=RΓ(XSyn,O{i}).R\Gamma_{\mathrm{Syn}}(X,\mathbb{Q}_p(i)) := R\Gamma(X^{\mathrm{Syn}}, \mathcal{O}\{i\}).9, and its pullbacks along pp0 and pp1 agree, so pp2 descends to pp3. This yields rational analytic syntomic cohomology in weight pp4: pp5 More generally, for pp6,

pp7

defines syntomic cohomology with coefficients in perfect analytic pp8-gauges (Hauck, 16 Apr 2026).

A central structural theorem is the fiber-square description

pp9

valid for X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K0 a Berkovich smooth derived Berkovich space over X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K1. For the unit object X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K2, this recovers the usual syntomic comparison pattern between Hyodo–Kato and filtered de Rham realizations. A second fiber-square description relates syntomic, divisor, and Hodge–Tate stacks: X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K3 This underlies the truncated comparison

X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K4

for the unit coefficient and, more generally, for vector bundle analytic X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K5-gauges with Hodge–Tate weights X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K6 (Hauck, 16 Apr 2026).

Rational analytic syntomic cohomology satisfies Poincaré duality. For the structural map

X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K7

the dualizing complex is

X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K8

If X/SpfOK\mathrm{X}/\mathrm{Spf}\,\mathcal{O}_K9 is smooth proper of pure relative dimension XSynX^{\mathrm{Syn}}00, then

XSynX^{\mathrm{Syn}}01

and for XSynX^{\mathrm{Syn}}02 smooth proper of dimension XSynX^{\mathrm{Syn}}03,

XSynX^{\mathrm{Syn}}04

The shift XSynX^{\mathrm{Syn}}05 at the base is attributed to the extra topological dimension of the Nygaard interval direction (Hauck, 16 Apr 2026).

The theory also carries a strong first Chern class formalism: XSynX^{\mathrm{Syn}}06 compatible with functoriality, additivity, pullback, and tensor product. The projective bundle formula is realized by the isomorphism built from powers of XSynX^{\mathrm{Syn}}07 for XSynX^{\mathrm{Syn}}08 (Hauck, 16 Apr 2026).

4. Vector bundles, de Rham coefficients, and the Fargues–Fontaine curve

The coefficient theory of syntomification is controlled by the relative Fargues–Fontaine curve. If XSynX^{\mathrm{Syn}}09 is smooth partially proper over XSynX^{\mathrm{Syn}}10, then

XSynX^{\mathrm{Syn}}11

where the right-hand side is the full subcategory of vector bundles on the relative Fargues–Fontaine curve XSynX^{\mathrm{Syn}}12 that are de Rham. Under this equivalence, de Rham XSynX^{\mathrm{Syn}}13-local systems on the pro-étale site embed fully faithfully into XSynX^{\mathrm{Syn}}14 (Hauck, 16 Apr 2026).

This description specializes cleanly at a point. For XSynX^{\mathrm{Syn}}15,

XSynX^{\mathrm{Syn}}16

the category of XSynX^{\mathrm{Syn}}17-equivariant de Rham vector bundles on the Fargues–Fontaine curve. For de Rham representations XSynX^{\mathrm{Syn}}18,

XSynX^{\mathrm{Syn}}19

and in particular

XSynX^{\mathrm{Syn}}20

Thus vector bundles on XSynX^{\mathrm{Syn}}21 are not auxiliary coefficients but a geometric model for classical de Rham XSynX^{\mathrm{Syn}}22-adic Hodge-theoretic objects (Hauck, 16 Apr 2026).

The same perspective explains the role of the Hyodo–Kato stack

XSynX^{\mathrm{Syn}}23

An object of XSynX^{\mathrm{Syn}}24 is simultaneously a Hyodo–Kato object on XSynX^{\mathrm{Syn}}25, a filtered de Rham object on XSynX^{\mathrm{Syn}}26, and a compatible object on XSynX^{\mathrm{Syn}}27. This places syntomification at the intersection of Frobenius, monodromy, filtration, and de Rham comparison data (Hauck, 16 Apr 2026).

5. Formal-scheme syntomification, crystalline local systems, and rationalization

For a smooth XSynX^{\mathrm{Syn}}28-adic formal scheme XSynX^{\mathrm{Syn}}29, syntomification is formulated in the language of XSynX^{\mathrm{Syn}}30-gauges. The heart XSynX^{\mathrm{Syn}}31 contains a reflexive subcategory XSynX^{\mathrm{Syn}}32, defined by the condition that the natural map

XSynX^{\mathrm{Syn}}33

is an isomorphism. The étale realization functor is symmetric monoidal, respects duals, and induces an equivalence

XSynX^{\mathrm{Syn}}34

where XSynX^{\mathrm{Syn}}35 is the rigid generic fiber and the target is the category of pro-étale crystalline XSynX^{\mathrm{Syn}}36-local systems. More generally, if XSynX^{\mathrm{Syn}}37, then every

XSynX^{\mathrm{Syn}}38

is a crystalline XSynX^{\mathrm{Syn}}39-local system on XSynX^{\mathrm{Syn}}40 (Pentland, 19 Oct 2025).

Rationalization removes integral syntomic torsion. The kernel of

XSynX^{\mathrm{Syn}}41

consists precisely of coherent XSynX^{\mathrm{Syn}}42-gauges killed by a power of XSynX^{\mathrm{Syn}}43. After inverting XSynX^{\mathrm{Syn}}44, one obtains

XSynX^{\mathrm{Syn}}45

and the essential image of

XSynX^{\mathrm{Syn}}46

is the full subcategory whose cohomology sheaves are crystalline XSynX^{\mathrm{Syn}}47-local systems. When XSynX^{\mathrm{Syn}}48 is smooth proper, there is a XSynX^{\mathrm{Syn}}49-exact symmetric monoidal equivalence

XSynX^{\mathrm{Syn}}50

where the target consists of perfect complexes whose cohomology sheaves are admissible filtered XSynX^{\mathrm{Syn}}51-isocrystals (Pentland, 19 Oct 2025).

These results identify syntomification as a rational bridge between integral XSynX^{\mathrm{Syn}}52-gauge geometry and analytic crystalline local systems. The role of rationalization is explicit: it passes from lattices and syntomic torsion to isogeny categories and admissible filtered XSynX^{\mathrm{Syn}}53-isocrystals (Pentland, 19 Oct 2025).

6. Broader rational–analytic motifs and adjacent frameworks

Two adjacent literatures isolate structural themes that illuminate the phrase “rational analytic syntomification,” even though they are not themselves XSynX^{\mathrm{Syn}}54-adic syntomic theories.

For relative semi-abelian schemes over an affine complex curve XSynX^{\mathrm{Syn}}55, the study of analytic and rational sections develops a direct comparison between algebraic and analytic height formalisms. The same differential XSynX^{\mathrm{Syn}}56-form XSynX^{\mathrm{Syn}}57 gives the Néron–Tate height of a rational section,

XSynX^{\mathrm{Syn}}58

and an analytic growth functional for a holomorphic section,

XSynX^{\mathrm{Syn}}59

The theory proves, among other statements, that if XSynX^{\mathrm{Syn}}60, then XSynX^{\mathrm{Syn}}61 must be rational, and that transcendental holomorphic sections have Zariski closures with positive-dimensional stabilizer; for strictly transcendental sections, after finite base change, the closure is a translate of an abelian subscheme by a rational section (Corvaja et al., 2020).

For discrete analytic functions on the lattice XSynX^{\mathrm{Syn}}62, rationality is redefined because pointwise multiplication does not preserve discrete analyticity. The relevant product is the convolution product XSynX^{\mathrm{Syn}}63, rational discrete analytic functions are realized by

XSynX^{\mathrm{Syn}}64

and discrete analytic Schur multipliers admit co-isometric realizations on de Branges–Rovnyak spaces. Rationality is equivalent to several finite-dimensional conditions, including the existence of a polynomial XSynX^{\mathrm{Syn}}65 such that XSynX^{\mathrm{Syn}}66 is polynomial and the finite-dimensionality of

XSynX^{\mathrm{Syn}}67

(Alpay et al., 2021).

These frameworks suggest a recurrent structural pattern. Analytic data are encoded by auxiliary geometric or operator-theoretic objects—cohomological stacks, kernels, or colligations—and rationality is detected by finite-dimensionality, bounded growth, or compatibility with a distinguished product. A plausible implication is that syntomification, in the narrow XSynX^{\mathrm{Syn}}68-adic sense of XSynX^{\mathrm{Syn}}69, belongs to a wider class of constructions in which one replaces a naive analytic object by a more structured carrier that simultaneously records analytic, algebraic, and realization-theoretic information (Corvaja et al., 2020, Alpay et al., 2021).

Within the XSynX^{\mathrm{Syn}}70-adic setting, that carrier is the syntomic stack itself. Its defining gluing identifies de Rham and Hodge–Tate incarnations of prismatised geometry; its line bundles produce rational analytic syntomic cohomology; its vector bundles recover de Rham bundles on the Fargues–Fontaine curve; and its rationalized perfect complexes recover crystalline local systems and admissible filtered XSynX^{\mathrm{Syn}}71-isocrystals (Hauck, 16 Apr 2026, Pentland, 19 Oct 2025).

Topic to Video (Beta)

No one has generated a video about this topic yet.

Whiteboard

No one has generated a whiteboard explanation for this topic yet.

Follow Topic

Get notified by email when new papers are published related to Rational Analytic Syntomification.