arXiv subjects

Sudhanva Joshi

Publications and source records attributed to Sudhanva Joshi.

6 recordsLinked to original sources

arXiv2026

Gravitational Wave-Inspired Scrambling Delay in Sachdev-Ye-Kitaev Wormhole Teleportation

In the Sachdev-Ye-Kitaev (SYK) model, traversable wormhole teleportation fidelity probes the many-body scrambling of holographic black holes. We apply a gravitational-wave-inspired periodic Floquet deformation derived from the lowest-dimensional bilinear $\text{SYK}_4$ sector to the boundary, thereby characterizing the channel response via exact numerical time evolution at $βJ = 2$. Re-optimizing under the drive isolates genuine physical effects from calibration mismatch, yielding four main results: (i) distinct perturbative and non-perturbative amplitude regimes separated near $\varepsilon \sim J$; (ii) a natural low-pass filter response, with maximum fidelity suppression at $ω\lesssim β^{-1}$ and monotonic recovery above the thermal scale; (iii) a scrambling delay, evidenced by a delayed fidelity peak under an inspiral chirp ($Δt_{\mathrm{scr}}^{(\mathrm{fid})} = +0.11\, J^{-1}$) and independently confirmed by OTOC measurements to grow monotonically with drive amplitude; and (iv) robust, non-zero fidelity suppression across $N \in \{10, 12, 14, 16\}$ Majorana modes. These findings establish that holographic wormholes degrade gracefully under metric-like boundary deformations, providing direct diagnostic signatures for near-term quantum hardware.

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arXiv2026

Black-Hole Microstate Hair Requires a Horizon Measurement

Can a smooth horizon hide its microstates? At fixed classical and superselected data, the exterior distinguishability $D_{\max}$ of same-sector infalling states and the departure $\varepsilon$ from isometric infall obey $D_{\max}^{2}+(1-2\varepsilon)^{2}\leq 1$, and every point is realized. Below maximal disruption, the boundary is reached only by which-state measurements: the distinguished pair crosses undisturbed while the exterior records which one fell in. The least a horizon can do to have microstate hair is measure what falls in. Classically hairy black holes are labeled backgrounds, not microstate hair.

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arXiv2026

Quantum magic is necessary but not sufficient for wormhole-inspired teleportation

We investigate the dynamics of Quantum magic, formally known as non-stabilizerness, quantified by the stabilizer Rényi entropy (SRE), across the stages of the wormhole-inspired teleportation protocol (WITP) in the Sachdev-Ye-Kitaev (SYK) model. By tracking the SRE of the full pure state across scrambling, message insertion, left-right coupling, and right-side extraction, we uncover a regime-dependent relationship between magic accumulation and teleportation fidelity. In the gravitational (low temperature) regime, fidelity rises concurrently with magic from early times, whereas in the peaked-size (high temperature) regime, the magic saturates near the Haar-typical value before teleportation onset. A baseline-subtracted diagnostic comparing coupled and uncoupled protocols reveals that the double-trace coupling first suppresses and then channels non-stabilizer resources toward the teleportation signal, with the channel amplitude decreasing monotonically with inverse temperature. Comparison with a chaotic random two-local model that generates near-maximal magic yet fails to teleport, and with a magic-free Clifford scrambler that fails equally despite mixing operators efficiently, demonstrates that structured magic redistribution, rather than the amount of non-stabilizerness, underlies successful wormhole traversal. Moreover, the magic transiently dips at the fidelity peak, marking the teleportation event in the time domain. Our results are robust across the three system sizes studied ($N_{\mathrm{maj}}=8,10,12$), and the fidelity-magic trajectories exhibit an approximate collapse when the SRE is normalized by the Haar-typical prediction.

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arXiv2026

Entanglement structure for finite system under dual-unitary dynamics

The dynamics of quantum many-body systems in the chaotic regime are of particular interest due to the associated phenomena of information scrambling and entanglement generation within the system. While these systems are typically intractable using traditional numerical methods, an effective framework can be implemented based on dual-unitary circuits which have emerged as a minimal model for maximally chaotic dynamics. In this work, we investigate how individual two-body operators influence the global dynamics of circuits composed of dual-unitaries. We study their effect on entanglement generation while examining it from both bipartite and multipartite perspectives. Here we also highlight the significant role of local unitaries in the dynamics when paired with operators from the dual-unitary class, showing that systems with identical entangling power can exhibit a range of differing entanglement growth rates. Furthermore, we present calculations establishing time-step-dependent lower bounds, which depend on both the initial state and the entangling power of the constituent operators. Finally, we find that time-evolving an initial state composed of pair products generates a state with nearly maximal multipartite entanglement content, approaching the bounds established by Absolutely Maximally Entangled (AME) states.

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arXiv2026

Traversability dynamics of minimal Sachdev-Ye-Kitaev Wormhole-inspired teleportation protocol with a parity-time ($\mathcal{PT}$)-symmetric non-Hermitian deformation

Holography-inspired teleportation has recently emerged as a significant area of research in quantum many-body systems. In this work, we investigate the effects of $\mathcal{PT}$ symmetric non-unitary deformations on the traversability of the wormhole-inspired teleportation protocol modeled by coupled Sachdev-Ye-Kitaev systems prepared in a Thermofield Double state bath. By introducing balanced gain and loss terms to the boundary Hamiltonians, we identify a phase transition driven by spectral exceptional points, where the real energy eigenvalues of the effective Hamiltonian coalesce and bifurcate into complex conjugate pairs. We demonstrate that the $\mathcal{PT}$-broken phase acts as an amplifier, enabling exponential growth in the norm of the teleported signal while preserving the causal time window for the wormhole's traversability. A statistical study of disorder realizations reveals that the critical non-Hermiticity threshold $γ_c$ follows a log-normal distribution, reflecting the sensitivity of the transition to the microscopic level spacing of the chaotic SYK spectrum. Furthermore, we observe a ``Purification" effect deep in the broken phase, where the teleportation channel acts as an entanglement distiller, yielding near-perfect teleportation fidelity for post-selected states. Our results suggest that the non-Hermitian topology can be harnessed to enhance holographic quantum communication, providing a robust mechanism for signal amplification in noisy, minimal quantum many-body systems.

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arXiv2025

SYK model based $β$ regime dependent two-qubit dynamical wormhole-inspired teleportation protocol simulation

We implement the Wormhole-Inspired Teleportation Protocol (WITP) in a pair of coupled Sachdev-Ye-Kitaev (SYK) models prepared in a thermofield-double state, forming a quantum analog of a traversable wormhole. By varying parameters (temperature, coupling strength, insertion site, and traversal time), we compare the teleportation fidelity against an analogous protocol using a transverse-field Ising model. We find that the chaotic SYK system consistently yields higher teleportation fidelity than the TFIM model, reflecting the SYK Hamiltonian's pronounced many-body chaos. These enhanced fidelities arise from the SYK's effectively random-matrix dynamics, which improve coherent information transfer through the wormhole channel. Unlike prior single-qubit benchmarks based on basis state inputs, the present work defines and evaluates a genuinely quantum-state fidelity for a maximally entangled two-qubit Bell input, using a Pauli-stabilizer formalism that captures entanglement-phase coherence. Our central result is achieved by teleporting a maximally entangled two-qubit Bell state through the wormhole. We introduce a Pauli-stabilizer fidelity measure for the two-qubit message and demonstrate that the Bell-state protocol produces a substantial fidelity boost compared to single-qubit teleportation. Furthermore, we examine the time-resolved fidelity for both single-qubit and two-qubit messages, revealing distinct fluctuation patterns that deepen the understanding of dynamical many-body teleportation processes. Finally, we present an argument that our Bell-state WITP simulations provide a concrete numerical testbed for aspects of the ER=EPR conjecture, by mapping entanglement structure and thermal/coupling dependence to traversability diagnostics in an emergent wormhole geometry.

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