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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Entropy scaling and simulability by matrix product states
Norbert Schuch1, Michael M Wolf, Frank Verstraete
1Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Strasse 1, Garching, Germany.
Physical Review Letters
|February 1, 2008
Summary
We explore how block entropies relate to simulating quantum systems with matrix product states (MPSs). Notably, even states with area laws aren't always MPS-approximable, impacting quantum computing simulations.
Area of Science:
- Quantum Information Theory
- Computational Physics
Background:
- Matrix product states (MPSs) are a powerful tool for simulating quantum many-body systems.
- Block entropies quantify entanglement and are crucial for understanding system complexity.
Purpose of the Study:
- To investigate the relationship between block entropy scaling and MPS approximability.
- To clarify this connection for both von Neumann and Rényi entropies.
- To assess the implications for quantum computation's advantage over classical simulation.
Main Methods:
- Analysis of block entropy scaling in quantum many-body systems.
- Theoretical investigation of MPS approximation capabilities.
- Application of entropy scaling results to quantum simulation scenarios.
Main Results:
- Established a precise connection between block entropy scaling and MPS approximability for von Neumann and Rényi entropies.
- Demonstrated that states obeying a strict area law for von Neumann entropy are not necessarily MPS-approximable.
- Identified conditions under which quantum computers may outperform classical computers in simulating quantum systems.
Conclusions:
- The efficiency of MPS simulations is intricately linked to block entropy scaling.
- Area laws alone do not guarantee MPS approximability, challenging some assumptions in condensed matter physics.
- Quantum computers hold potential for simulating complex quantum dynamics, even for translationally invariant systems.
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