# Entanglement devised barren plateau mitigation

@article{Patti2021EntanglementDB, title={Entanglement devised barren plateau mitigation}, author={Taylor Lee Patti and Khadijeh Najafi and Xun Gao and Susanne F. Yelin}, journal={Physical Review Research}, year={2021} }

Hybrid quantum-classical variational algorithms are one of the most propitious implementations of quantum computing on near-term devices, offering classical machine learning support to quantum scale solution spaces. However, numerous studies have demonstrated that the rate at which this space grows in qubit number could preclude learning in deep quantum circuits, a phenomenon known as barren plateaus. In this work, we implicate random entanglement as the source of barren plateaus and… Expand

#### 27 Citations

Noise-induced barren plateaus in variational quantum algorithms

- Physics, Computer Science
- Nature communications
- 2021

This work rigorously proves a serious limitation for noisy VQAs, in that the noise causes the training landscape to have a barren plateau (i.e., vanishing gradient), and implements numerical heuristics that confirm the NIBP phenomenon for a realistic hardware noise model. Expand

Absence of Barren Plateaus in Quantum Convolutional Neural Networks

- Physics, Computer Science
- Physical Review X
- 2021

This work rigorously analyze the gradient scaling for the parameters in the QCNN architecture and finds that the variance of the gradient vanishes no faster than polynomially, implying that QCNNs do not exhibit barren plateaus. Expand

Variational Quantum Optimization with Multi-Basis Encodings

- Physics
- 2021

Despite extensive research efforts, few quantum algorithms for classical optimization demonstrate realizable quantum advantage. The utility of many quantum algorithms is limited by high requisite… Expand

Nonlinear Quantum Optimization Algorithms via Efficient Ising Model Encodings

- 2021

Despite extensive research efforts, few quantum algorithms for classical optimization demonstrate realizable advantage. The utility of many quantum algorithms is limited by high requisite circuit… Expand

Experimental quantum learning of a spectral decomposition

- Physics
- Physical Review Research
- 2021

Currently available quantum hardware allows for small scale implementations of quantum machine learning algorithms. Such experiments aid the search for applications of quantum computers by… Expand

Equivalence of quantum barren plateaus to cost concentration and narrow gorges

- Computer Science, Physics
- ArXiv
- 2021

This work analytically proves the connection between three different landscape features that have been observed for PQCs: exponentially vanishing gradients, exponential cost concentration about the mean, and the exponential narrowness of minina. Expand

Recent advances for quantum classifiers

- Computer Science, Physics
- ArXiv
- 2021

This review gives a relatively comprehensive overview of quantum classifiers, including a number of quantum classification algorithms, including quantum support vector machine, quantum kernel methods, quantum decision tree, and quantum nearest neighbor algorithm. Expand

Effect of barren plateaus on gradient-free optimization

- Computer Science, Physics
- Quantum
- 2021

It is shown that gradient-free optimizers do not solve the barren plateau problem, and the main result proves that cost function differences, which are the basis for making decisions in a gradient- free optimization, are exponentially suppressed in a barren plateau. Expand

F-Divergences and Cost Function Locality in Generative Modelling with Quantum Circuits

- Computer Science, Physics
- Entropy
- 2021

This work generalises existing algorithms for estimating the Kullback–Leibler divergence and the total variation distance to obtain a fault-tolerant quantum algorithm for estimating another f-divergence, namely, the Pearson divergence. Expand

Neural predictor based quantum architecture search

- Computer Science, Physics
- Machine Learning: Science and Technology
- 2021

It is demonstrated a neural predictor guided QAS can discover powerful quantum circuit ansatz, yielding state-of-the-art results for various examples from quantum simulation and quantum machine learning. Expand

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This work rigorously proves a serious limitation for noisy VQAs, in that the noise causes the training landscape to have a barren plateau (i.e., vanishing gradient), and implements numerical heuristics that confirm the NIBP phenomenon for a realistic hardware noise model. Expand

Absence of Barren Plateaus in Quantum Convolutional Neural Networks

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