Space-bounded quantum interactive proof systems
- URL: http://arxiv.org/abs/2410.23958v1
- Date: Thu, 31 Oct 2024 14:11:08 GMT
- Title: Space-bounded quantum interactive proof systems
- Authors: François Le Gall, Yupan Liu, Harumichi Nishimura, Qisheng Wang,
- Abstract summary: We introduce two models of space-bounded quantum interactive proof systems, $sf QIPL$ and $sf QIP_rm UL$.
The $sf QIP_rm UL$ model restricts verifier actions to unitary circuits. In contrast, $sf QIPL$ allows logarithmically many intermediate measurements per verifier action.
- Score: 2.623117146922531
- License:
- Abstract: We introduce two models of space-bounded quantum interactive proof systems, ${\sf QIPL}$ and ${\sf QIP_{\rm U}L}$. The ${\sf QIP_{\rm U}L}$ model, a space-bounded variant of quantum interactive proofs (${\sf QIP}$) introduced by Watrous (CC 2003) and Kitaev and Watrous (STOC 2000), restricts verifier actions to unitary circuits. In contrast, ${\sf QIPL}$ allows logarithmically many intermediate measurements per verifier action (with a high-concentration condition on yes instances), making it the weakest model that encompasses the classical model of Condon and Ladner (JCSS 1995). We characterize the computational power of ${\sf QIPL}$ and ${\sf QIP_{\rm U}L}$. When the message number $m$ is polynomially bounded, ${\sf QIP_{\rm U}L} \subsetneq {\sf QIPL}$ unless ${\sf P} = {\sf NP}$: - ${\sf QIPL}$ exactly characterizes ${\sf NP}$. - ${\sf QIP_{\rm U}L}$ is contained in ${\sf P}$ and contains ${\sf SAC}^1 \cup {\sf BQL}$, where ${\sf SAC}^1$ denotes problems solvable by classical logarithmic-depth, semi-unbounded fan-in circuits. However, this distinction vanishes when $m$ is constant. Our results further indicate that intermediate measurements uniquely impact space-bounded quantum interactive proofs, unlike in space-bounded quantum computation, where ${\sf BQL}={\sf BQ_{\rm U}L}$. We also introduce space-bounded unitary quantum statistical zero-knowledge (${\sf QSZK_{\rm U}L}$), a specific form of ${\sf QIP_{\rm U}L}$ proof systems with statistical zero-knowledge against any verifier. This class is a space-bounded variant of quantum statistical zero-knowledge (${\sf QSZK}$) defined by Watrous (SICOMP 2009). We prove that ${\sf QSZK_{\rm U}L} = {\sf BQL}$, implying that the statistical zero-knowledge property negates the computational advantage typically gained from the interaction.
Related papers
- Low-degree approximation of QAC$^0$ circuits [0.0]
We show that the parity function cannot be computed in QAC$0$.
We also show that any QAC circuit of depth $d$ that approximately computes parity on $n$ bits requires $2widetildeOmega(n1/d)$.
arXiv Detail & Related papers (2024-11-01T19:04:13Z) - Classical versus quantum queries in quantum PCPs with classical proofs [0.3004066195320147]
We generalize quantum-classical PCPs to allow for $q$ quantum queries to a classical proof.
Surprisingly, this shows that we can amplify the promise gap from inverse to constant for constant query quantum-classicals.
Even though we can achieve promise gap, our result also gives strong evidence that there exists no constant query quantum-classical PCP for $mathsfQCMA$.
arXiv Detail & Related papers (2024-11-01T18:00:56Z) - On estimating the trace of quantum state powers [2.637436382971936]
We investigate the computational complexity of estimating the trace of quantum state powers $texttr(rhoq)$ for an $n$-qubit mixed quantum state $rho$.
Our speedup is achieved by introducing efficiently computable uniform approximations of positive power functions into quantum singular value transformation.
arXiv Detail & Related papers (2024-10-17T13:57:13Z) - Unconditionally separating noisy $\mathsf{QNC}^0$ from bounded polynomial threshold circuits of constant depth [8.66267734067296]
We study classes of constant-depth circuits with bounds that compute restricted threshold functions.
For large enough values of $mathsfbPTFC0[k]$, $mathsfbPTFC0[k] contains $mathsfTC0[k].
arXiv Detail & Related papers (2024-08-29T09:40:55Z) - A shortcut to an optimal quantum linear system solver [55.2480439325792]
We give a conceptually simple quantum linear system solvers (QLSS) that does not use complex or difficult-to-analyze techniques.
If the solution norm $lVertboldsymbolxrVert$ is known exactly, our QLSS requires only a single application of kernel.
Alternatively, by reintroducing a concept from the adiabatic path-following technique, we show that $O(kappa)$ complexity can be achieved for norm estimation.
arXiv Detail & Related papers (2024-06-17T20:54:11Z) - Neural network learns low-dimensional polynomials with SGD near the information-theoretic limit [75.4661041626338]
We study the problem of gradient descent learning of a single-index target function $f_*(boldsymbolx) = textstylesigma_*left(langleboldsymbolx,boldsymbolthetarangleright)$ under isotropic Gaussian data.
We prove that a two-layer neural network optimized by an SGD-based algorithm learns $f_*$ of arbitrary link function with a sample and runtime complexity of $n asymp T asymp C(q) cdot d
arXiv Detail & Related papers (2024-06-03T17:56:58Z) - Dimension Independent Disentanglers from Unentanglement and Applications [55.86191108738564]
We construct a dimension-independent k-partite disentangler (like) channel from bipartite unentangled input.
We show that to capture NEXP, it suffices to have unentangled proofs of the form $| psi rangle = sqrta | sqrt1-a | psi_+ rangle where $| psi_+ rangle has non-negative amplitudes.
arXiv Detail & Related papers (2024-02-23T12:22:03Z) - On the Role of Entanglement and Statistics in Learning [3.729242965449096]
We make progress in understanding the relationship between learning models with access to entangled, separable and statistical measurements.
We exhibit a class $C$ that gives an exponential separation between QSQ learning and quantum learning with entangled measurements.
We prove superpolynomial QSQ lower bounds for testing purity, shadow tomography, Abelian hidden subgroup problem, degree-$2$ functions, planted bi-clique states and output states of Clifford circuits of depth.
arXiv Detail & Related papers (2023-06-05T18:16:03Z) - Nonlocality under Computational Assumptions [51.020610614131186]
A set of correlations is said to be nonlocal if it cannot be reproduced by spacelike-separated parties sharing randomness and performing local operations.
We show that there exist (efficient) local producing measurements that cannot be reproduced through randomness and quantum-time computation.
arXiv Detail & Related papers (2023-03-03T16:53:30Z) - The Approximate Degree of DNF and CNF Formulas [95.94432031144716]
For every $delta>0,$ we construct CNF and formulas of size with approximate degree $Omega(n1-delta),$ essentially matching the trivial upper bound of $n.
We show that for every $delta>0$, these models require $Omega(n1-delta)$, $Omega(n/4kk2)1-delta$, and $Omega(n/4kk2)1-delta$, respectively.
arXiv Detail & Related papers (2022-09-04T10:01:39Z) - A lower bound on the space overhead of fault-tolerant quantum computation [51.723084600243716]
The threshold theorem is a fundamental result in the theory of fault-tolerant quantum computation.
We prove an exponential upper bound on the maximal length of fault-tolerant quantum computation with amplitude noise.
arXiv Detail & Related papers (2022-01-31T22:19:49Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.