On Classical and Hybrid Shadows of Quantum States
- URL: http://arxiv.org/abs/2206.06616v2
- Date: Sun, 20 Nov 2022 19:04:22 GMT
- Title: On Classical and Hybrid Shadows of Quantum States
- Authors: Saumya Shivam, C. W. von Keyserlingk, S. L. Sondhi
- Abstract summary: Classical shadows are a computationally efficient approach to storing quantum states on a classical computer.
We discuss the advantages and limitations of using classical shadows to simulate many-body dynamics.
We introduce the notion of a hybrid shadow, constructed from measurements on a part of the system instead of the entirety.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Classical shadows are a computationally efficient approach to storing quantum
states on a classical computer for the purposes of estimating expectation
values of local observables, obtained by performing repeated random
measurements. In this note we offer some comments on this approach. We note
that the resources needed to form classical shadows with bounded relative error
depend strongly on the target state. We then comment on the advantages and
limitations of using classical shadows to simulate many-body dynamics. In
addition, we introduce the notion of a hybrid shadow, constructed from
measurements on a part of the system instead of the entirety, which provides a
framework to gain more insight into the nature of shadow states as one reduces
the size of the subsystem measured, and a potential alternative to compressing
quantum states.
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