Traversable Wormhole Teleportation

• Traversable wormhole teleportation is a holographically-inspired protocol that uses entanglement and boundary couplings to enable quantum state transfer across an Einstein–Rosen bridge.
• The mechanism relies on inducing negative averaged null energy via double-trace deformations, which shifts null geodesics and briefly opens a causal transmission window.
• Implementations using models like SYK and experimental quantum processors illustrate its potential to probe quantum gravity, scrambling dynamics, and information transfer.

Traversable wormhole teleportation is a class of holographically motivated quantum-information protocols in which quantum information is transferred between two entangled many-body systems by a sequence that, in semiclassical gravity, is dual to rendering an Einstein–Rosen bridge traversable for a brief interval. The canonical setting begins with a thermofield double state of two identical systems, introduces a controlled left–right interaction, and diagnoses transmission by boundary correlators, mutual information, or related entanglement measures. In the gravitational description, the interaction produces negative averaged null energy, shifts null geodesics, and opens a causal window through the wormhole; in the boundary description, the same process is interpreted as teleportation implemented by entanglement, scrambling, weak coupling, and decoding (Gao et al., 2016, Susskind et al., 2017, Gao et al., 2019).

1. Foundational construction and holographic meaning

The modern formulation of traversable wormhole teleportation originates in the observation that a two-sided eternal black hole, dual to a thermofield double state of two boundary theories, can be made traversable by a direct coupling between the boundaries. In the original double-trace construction, the interaction is

$$S=\int dt\, d^{d-1}x\, h(t,x)\, O_R(t,x)\, O_L(-t,x),$$

or equivalently

$$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$

with the left operator evaluated at $-t$ because the two wedges have opposite time orientations (Gao et al., 2016). The shared state is the thermofield double,

$$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$

which geometrizes the left–right entanglement as a non-traversable wormhole (Ahn et al., 2020).

This framework gave operational content to the ER=EPR relation. Entanglement alone supplies the bridge, but not traversability; the additional coupling provides the channel that turns the bridge into a transmission medium (Gao et al., 2016). A related interpretation was developed in the quantum-teleportation language: the entangled thermofield double plays the role of the shared resource, while the inter-boundary interaction replaces the classical-control step in standard teleportation, with the bulk excitation identified as the teleported system (Susskind et al., 2017). In that sense, the protocol is neither ordinary circuit teleportation nor unconstrained geometric travel through spacetime. It is a dual description of a single process in which the same boundary operations admit both an information-theoretic and a bulk-geometric interpretation (Susskind et al., 2017).

A further refinement emphasized that the teleportee may, in principle, retain memory of what it encountered in the wormhole interior. In that formulation, the state exiting on the right is not required to be dynamically trivial; interactions in the interior can imprint information on the recovered system (Susskind et al., 2017). This suggests that traversable wormhole teleportation is best understood not merely as state transfer but as state transfer through a specific dynamical channel.

2. Mechanism of traversability: negative null energy, backreaction, and causal opening

Traversability is produced by a quantum violation of the averaged null energy condition. In the original AdS construction, the boundary interaction modifies bulk boundary conditions and generates a negative pulse of null energy on the horizon. The relevant criterion is

$$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$

and on the horizon the crucial component is $T_{UU}$ (Gao et al., 2016). The resulting gravitational backreaction shifts the null coordinate so that a light ray that would otherwise remain trapped can emerge on the opposite boundary. In Kruskal coordinates, the shift is summarized by

$$V(U)=-(2g_{UV}(0))^{-1}\int_{-\infty}^{U} dU\, h_{UU},$$

and negative averaged null energy implies $V(+\infty)<0$, which is the geometric statement that the wormhole has opened (Gao et al., 2016).

In nearly-$AdS_2$ gravity, the same effect admits a particularly explicit description. The metric remains locally $AdS_2$, while the dilaton encodes the backreaction. A double-trace deformation

$$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$0

shifts the dilaton and the singularity structure so that the future singularity is displaced away from the boundary light cone, thereby creating a traversable window (Bak et al., 2018). The same work verified that the accompanying change in energy and entropy satisfies the black-hole first law, so the opening is not an isolated kinematic effect but part of a consistent thermodynamic response (Bak et al., 2018).

Higher-dimensional generalizations retain the same logic but alter its quantitative strength. In hyperbolic slicing of AdS, the null shift is

$$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$1

and the corresponding averaged null energy can be computed analytically for both step-function and instantaneous deformations (Ahn et al., 2020). A key result is that the ANEC violation becomes smaller as spacetime dimension increases, so the amount of information that can be transmitted through the wormhole decreases with dimension (Ahn et al., 2020).

Several variants replace scalar double-trace couplings by other operators while preserving the same semiclassical mechanism. A current–current deformation,

$$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$2

induces negative null energy through the bulk Maxwell sector in the hydrodynamic limit, opening the wormhole by a gauge-field analogue of the Gao–Jafferis–Wall mechanism (Ahn et al., 2022). On the string worldsheet, a derivative double-trace deformation,

$$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$3

likewise produces the required negative-energy effect and yields a worldsheet traversable wormhole associated with a Bell pair of string endpoints (Boer et al., 2022). A distinct route dispenses with explicit boundary coupling altogether: local bulk Weyl fermions on a $$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$4 quotient geometry can generate negative averaged null energy semiclassically, rendering the quotient wormhole traversable perturbatively (Marolf et al., 2019).

The bulk opening does not violate causality. The boundaries are explicitly coupled, the relevant null geodesics are not achronal, and the construction does not produce closed timelike curves; moreover, the opening is tiny and temporary rather than a mechanism for superluminal transport through ordinary space (Gao et al., 2016). That restriction is central to the subject: traversable wormhole teleportation modifies the causal structure of the coupled system, not the causal structure of the decoupled theories.

3. Boundary protocol, observables, and teleportation diagnostics

The boundary protocol is typically formulated with a message qubit, a reference qubit, two entangled many-body systems, and a readout qubit or subsystem. In a standard SYK realization, the initial state may be written schematically as

$$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$5

followed by message insertion on the left, unitary time evolution under the two many-body Hamiltonians, an instantaneous inter-side kick, and right-side readout (Byun et al., 11 Apr 2026). In one explicit formulation the coupling is

$$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$6

with $$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$7 corresponding to the negative-energy, traversable-wormhole regime in that sign convention (Byun et al., 11 Apr 2026).

A central diagnostic is the mutual information between the reference qubit and the target qubit,

$$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$8

because successful teleportation restores correlations between them (Byun et al., 11 Apr 2026). In hardware-oriented and finite-size studies, sign dependence of the coupling is a primary observable. The asymmetry

$$H(t)=-\int d\phi\, h(t,\phi)\, O_R(t,\phi)\, O_L(-t,\phi),$$9

is expected to be positive near the transmission window if the traversable channel is functioning (Byun et al., 11 Apr 2026).

Other formulations employ the reduced density matrix of the reference and output systems. In an SYK protocol based on explicit qubit insertion and extraction, perfect teleportation corresponds to maximal entanglement between the reference $-t$0 and the output $-t$1, diagnosed by

$-t$2

with the ideal value $-t$3 (Gao et al., 2019). In finite-qubit all-to-all systems, the same reduced state is analyzed through both mutual information and entanglement negativity,

$-t$4

which distinguishes total correlations from genuinely quantum entanglement in the recovered message (Liu et al., 2024).

Two-sided commutators provide a more direct causal diagnostic. In higher-dimensional holographic teleportation, the commutator built from operators on opposite boundaries becomes nonzero precisely when the signal can traverse the wormhole (Ahn et al., 2020). In the worldsheet setting, the same criterion appears through the imaginary part of a two-sided correlator in the eikonal regime (Boer et al., 2022). These observables are significant because a large teleportation signal alone is not sufficient to establish geometric traversability; sign asymmetry, time ordering, and nontrivial causal response are the sharper diagnostics (Liu et al., 2024).

4. SYK realizations, operator growth, and size-based formulations

The Sachdev–Ye–Kitaev model became the canonical boundary realization because, at low energy and large $-t$5, it is dual to nearly-$-t$6 gravity and displays the scrambling structure needed for the wormhole protocol (Byun et al., 11 Apr 2026). A concrete SYK teleportation scheme inserts a qubit into one side at early time, lets it scramble, applies a simple bilinear left–right coupling, and extracts the qubit on the other side. In this formulation, the coupling

$-t$7

and simple SWAP operations suffice; no complicated precursor decoding is required (Gao et al., 2019). An improved version based on composite fermions can approach unit fidelity in the large-$-t$8, low-temperature regime, with the maximal mutual information tending to perfect teleportation as $-t$9 (Gao et al., 2019).

A major conceptual development rephrased the protocol in terms of operator growth. “Teleportation by size” identifies operator size as the boundary quantity that governs transmission: under scrambling, a simple operator expands into a superposition of Pauli or Majorana strings, and the weak left–right coupling adds a phase that depends approximately on size (Brown et al., 2019). In that picture, successful transmission occurs when the coupling unwinds the phase structure acquired under scrambling. The associated size distribution is encoded in

$$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$0

and a special linear organization of phases with operator size was termed size winding (Brown et al., 2019). In holographic systems, perfect or near-perfect size winding was proposed as the boundary shadow of a signal traversing a semiclassical wormhole.

A broader framework then showed that the same circuit can operate by a distinct microscopic mechanism in generic thermalizing systems. “Peaked-size teleportation” uses the fact that, when the size distribution is narrowly peaked, the coupling effectively applies a nearly uniform phase to the evolved operator, enabling state transfer without relying on a semiclassical bulk geometry (Schuster et al., 2021). At finite temperature, however, the magnitude of the relevant correlators is bounded by thermal two-point functions, whereas low-temperature gravitational teleportation can produce order-one correlator magnitudes (Schuster et al., 2021). This distinction is central: the boundary circuit is not uniquely diagnostic of gravity.

Finite-$$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$1 analyses sharpen that point. In strongly chaotic systems near maximal chaos, clean semiclassical wormhole signatures require strong effective coupling $$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$2, small $$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$3, and large system size. A scramblon effective theory of finite-qubit systems concluded that the teleportation signal rapidly diminishes as $$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$4 is reduced, washing out both causal ordering and the sign asymmetry expected from emergent geometry (Liu et al., 2024). The same work contrasted this with weakly interacting systems, where the signal can increase as $$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$5 decreases (Liu et al., 2024). This suggests that observed many-body teleportation in small systems must be interpreted with care.

5. Experimental and numerical implementations

The protocol has been adapted to noisy intermediate-scale quantum hardware by replacing dense SYK Hamiltonians with sparse but chaotic variants. A recent implementation used a chaotic binary sparse $$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$6 SYK model whose couplings preserve spectral chaos while reducing circuit depth sufficiently for a quantum processor (Byun et al., 11 Apr 2026). The model was validated by the Gaussian-filtered spectral form factor and the gap-ratio diagnostic $$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$7, which remained close to the Gaussian orthogonal ensemble expectation down to approximately $$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$8 retained interaction terms (Byun et al., 11 Apr 2026). The experimental protocol employed variational TFD preparation, single-step first-order Lie–Trotter evolution, and tomography, reaching about 92% TFD fidelity with 35 echoed cross-resonance gates; the full run used 10 qubits, about 377 two-qubit gates per measurement setting and sign of $$|\mathrm{TFD}\rangle = Z^{-1/2}\sum_n e^{-\beta E_n/2}\,|E_n\rangle_L\otimes |E_n\rangle_R,$$9, and circuit depth about 1000 (Byun et al., 11 Apr 2026).

The principal observed signature in that implementation was a clear sign-dependent asymmetry in the mutual information near the expected transmission window: $$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$0 was larger for $$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$1 than for $$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$2, even though noise suppressed the raw magnitudes relative to exact numerics (Byun et al., 11 Apr 2026). Additional checks included approximate size winding and robustness across disorder realizations in the $$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$3 ensemble (Byun et al., 11 Apr 2026). This establishes an experimentally accessible version of traversable-wormhole-inspired teleportation driven by a chaotic Hamiltonian rather than by a specially trained commuting model.

Other simulation studies probed how the channel behaves under external perturbations. A gravitational-wave-inspired Floquet deformation of the SYK boundary,

$$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$4

was found to suppress teleportation fidelity coherently in a frequency-selective way at $$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$5 (Joshi et al., 19 Mar 2026). The response separated into two amplitude regimes near $$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$6, behaved as a low-pass filter most sensitive at $$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$7, and produced a positive scrambling delay in both fidelity and OTOC diagnostics: $$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$8 with no systematic finite-size suppression across $$\int_{-\infty}^{+\infty} T_{\mu\nu} k^\mu k^\nu\, d\lambda < 0,$$9 (Joshi et al., 19 Mar 2026). This indicates that the teleportation channel can function as a probe of driven scrambling dynamics.

Alternative digital simulations have emphasized state fidelity rather than mutual information. A wormhole-inspired teleportation protocol based on SYK dynamics and TFD preparation compared favorably with a transverse-field Ising baseline, and a two-qubit Bell-state message was diagnosed by the stabilizer-based fidelity

$T_{UU}$0

with $T_{UU}$1, $T_{UU}$2, and $T_{UU}$3 (Joshi et al., 18 Jun 2025). That study reported a maximum Bell-state fidelity of about $T_{UU}$4 at $T_{UU}$5, with fidelity decreasing as $T_{UU}$6 increases and then saturating; it also fit an empirical decay form with coherence scale $T_{UU}$7 (Joshi et al., 18 Jun 2025). This suggests that multipartite wormhole-inspired transmission can be benchmarked beyond the single-qubit case, although the protocol there is presented explicitly as an analog construction rather than a direct demonstration of semiclassical traversability.

6. Generalizations, probe dependence, and critical reassessment

The subject has broadened beyond the original AdS$T_{UU}$8 scalar-coupling setup. In Rindler-AdS/CFT, higher-dimensional traversable wormholes admit analytic ANEC formulas, eikonal derivations, and information-transfer bounds that shrink with spacetime dimension (Ahn et al., 2020). For localized perturbations in that setting, the optimal transmission region is controlled not by the light cone but by the butterfly cone, with butterfly speed

$T_{UU}$9

under the specified large-$$V(U)=-(2g_{UV}(0))^{-1}\int_{-\infty}^{U} dU\, h_{UU},$$0 and localized-shock conditions (Ahn et al., 2020). This makes the connection between chaos and traversable-wormhole teleportation quantitatively explicit.

Probe dependence appears sharply in asymptotically flat four-dimensional magnetic wormholes. Low-frequency scattering off the Maldacena–Milekhin–Popov wormhole shows that neutral and charged scalars are generally poor information carriers at low frequency, exhibiting strong reflection except at resonant frequencies; at late times their accumulated transmission cross-section approaches one half of the corresponding black-hole absorption cross-section (Freivogel et al., 10 Jun 2026). By contrast, charged massless fermions traverse with essentially unit probability in the low-energy regime because the lowest-Landau-level channel removes the centrifugal barrier (Freivogel et al., 10 Jun 2026). This demonstrates that “traversable” does not imply uniformly transmissive: the channel quality depends strongly on the probe.

A different generalization, highly formal and non-holographic in spirit, proposes gateway-like traversable wormholes with restricted polar sector and distribution-valued geometry. In that construction the negative energy of the Morris–Thorne geometry,

$$V(U)=-(2g_{UV}(0))^{-1}\int_{-\infty}^{U} dU\, h_{UU},$$1

is reduced to

$$V(U)=-(2g_{UV}(0))^{-1}\int_{-\infty}^{U} dU\, h_{UU},$$2

and vanishes in an ideal limit supported by non-metricity and hypermomentum rather than by ordinary matter (Mehta, 2022). A plausible implication is that the term “traversable wormhole teleportation” is now used across both holographic and non-holographic literatures, though the underlying mechanisms are not comparable.

The most consequential controversy concerns the interpretation of small-system experiments. A critical comment on the 2022 quantum-processor claim argued that the learned seven-Majorana Hamiltonian used there,

$$V(U)=-(2g_{UV}(0))^{-1}\int_{-\infty}^{U} dU\, h_{UU},$$3

is fully commuting, does not thermalize, reproduces the desired teleportation curve only for the operator pair used in machine-learning training, and exhibits “perfect size winding” as a generic small-commuting-system artifact rather than a gravitational signature (Kobrin et al., 2023). In that analysis, individual two-point and four-point correlators show oscillations and revivals rather than robust decay, and the strong-looking size-winding diagnostic is attributed to the tiny number of nonzero operator coefficients in such models (Kobrin et al., 2023). The critique does not deny that the protocol reproduces selected SYK-like observables; it denies that such reproduction establishes genuine wormhole or black-hole dynamics.

That reassessment aligns with a broader caution already present in the operator-growth literature: a successful teleportation signal does not by itself prove a semiclassical wormhole (Brown et al., 2019, Schuster et al., 2021). The weight of current evidence therefore supports a layered interpretation. Some protocols realize the full holographic mechanism of traversability in analytically controlled models; some experiments implement wormhole-inspired teleportation in chaos-preserving many-body systems; and some small-system demonstrations are better understood as trained or finite-size mimics of selected diagnostics rather than as direct realizations of emergent bulk geometry (Kobrin et al., 2023, Liu et al., 2024).