The Biological Qubit: Calcium Phosphate Dimers, Not Trimers.

Area of Science:

• Quantum biology
• Biophysics
• Molecular dynamics

Background:

• The Posner molecule (calcium phosphate trimer) was proposed as a biological quantum information processor.
• Its function relies on long-lived entangled 31P nuclear spin states.
• Recent findings revealed the molecule's asymmetry, challenging previous assumptions.

Purpose of the Study:

• Investigate spin dynamics of entangled 31P nuclear spins in the asymmetric Posner molecule.
• Determine if the Posner molecule can support quantum information processing for neural functions.
• Explore alternative calcium phosphate structures for quantum information processing.

Main Methods:

• Computational simulations of nuclear spin dynamics.
• Analysis of entanglement decay rates in asymmetric molecular ensembles.
• Comparison of spin coherence times between Posner molecules and dimers.

Main Results:

• Entanglement in the Posner molecule decays rapidly (subsecond timescale).
• This decay is too fast for supercellular neural processing.
• Calcium phosphate dimers exhibit robust entanglement preservation (hundreds of seconds).

Conclusions:

• The Posner molecule's asymmetry prevents long-lived entangled states for neural processing.
• Calcium phosphate dimers show potential as quantum information processors in biological systems.
• This suggests a revised model for quantum effects in neural function.