Knowledge Tree
buffer spins
Also known as: buffer spin
Facts (16)
Sources
Quantum Models of Consciousness from a Quantum Information ... arxiv.org Dec 20, 2024 16 facts
claimEntanglement protection time in the buffer network is optimal when interactions between buffer spins are enabled.
claimIn the non-interacting case, the central spin is weakly coupled to independent and locally dissipating buffer spins, resulting in more Markovian dynamics.
formulaThe initial cluster state of the quantum system is represented as a product state of the central spin and the buffer spins.
claimIn the authors' model of a phosphate molecule, the system consists of a central spin (phosphorus atom) surrounded by buffer spins (oxygen atoms), where the buffer spins interact with thermal baths while the central spin remains isolated from direct environmental interactions.
claimIn the quantum model described in the paper, applying a unitary transformation to the Hamiltonian allows for a transition from a fully connected graph of buffer spins to a representation where buffer spins do not interact with each other, referred to as the 'dressed picture' with 'dressed buffer spins'.
claimWhen the buffer spins do not form a perfectly complete graph (specifically when the interaction between spin 2 and spin 6 is missing), the central spin is coupled to only two dressed buffer spins.
claimIn the dressed picture, separate baths acting locally on each buffer spin become global baths acting collectively on the dressed buffer spins.
imageFigure 1 in the paper 'Quantum Models of Consciousness from a Quantum Information Perspective' illustrates the logarithmic negativity over time between two central spins in different geometries with interaction between buffer spins.
claimThe quantum system is modeled as an open system where central spins in both networks are entangled with each other, while the surrounding buffer spins remain in a thermal state.
claimThe buffer spins in the quantum model reach thermal equilibrium with the environment at an inverse temperature beta.
claimThe decoupling of the central spin from most of the dressed buffer spins in the described model is a result of the system Hamiltonian being highly symmetric.
claimThe dynamics of a central spin coupled to non-interacting buffer spins exhibit a roughly flat spectral density of the environment, which is an exact result.
claimEntanglement is conserved for an extended duration in spin network geometries with maximum connectivity between buffer spins.
formulaThe thermal state of the buffer spins is defined by the equation rho = exp(-beta * H_buffer) / Z, where Z is the partition function and the Boltzmann constant is assumed to be 1.
claimThe problem of a central spin coupled to a network of fully connected buffer spins can be mapped to the problem of a central spin coupled to a collection of non-interacting fictitious buffer spins through a specific change of variables.
claimLocal thermal dissipation channels in the spin network are described by a dissipator equation that assumes weakly coupled buffer spins.