Draft:Bloch sphere representation in mode-counting quantum models

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Quantum Computing using Bloch sphere

Bloch Sphere Quantum Computing Relation to the Bloch Sphere The C-Wave model can be described using the Bloch sphere, a standard representation of single-qubit states in quantum computing. Each point on the Bloch sphere corresponds to a possible qubit state, providing a geometric visualization of superposition and phase. By mapping C-Wave’s mode-counting approach onto the Bloch sphere, the model can be related to conventional qubit-based quantum computing, allowing comparison with established quantum information frameworks.

Introduction

The Bloch sphere model was developed to revise an earlier, inconsistent formulation. The main objectives are:

  • To make the mathematical formulation physically consistent.
  • To define the parameter C unambiguously.
  • To connect the concept to quantum information theory.
  • To establish testable relationships and provide numerical estimates.
 
Schematic

New formula and meaning of C

Original formula

 

Problems:

  • Units are not consistent.
  • C undefined.
  • Exponential scaling without physical justification.

Revised formula (mode-counting)

 

where:

  •   (polarization factor)
  •   = maximum frequency cut-off
  •   = speed of light

Definition of C

 

  • Qubit encoding:  
  • Continuous-variable encoding:  , where   is the maximum photon number.
 
Parameter

Derivation from mode-counting

  1. Volume of a sphere:  
  2. Number of spatial modes up to  :  
  3. Time-slot factor:  
  4. Total number of orthogonal slots:  
  5. Relation to original notation: with  :  

Numerical examples

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Scenario        
A — Superconducting chip 5 mm 10 GHz 300 μs  
B — Optical scale 1 cm 200 THz 1 μs  
C — Microscale 1 μm 1 THz 1 ns  
 
Scenarios

Implications and limitations

  • Control and addressing: Large   does not automatically imply usable capacity; hardware constraints matter.
  • Coherence and dephasing: Limit the effectively usable time  .
  • Energy cut-offs: Necessary in CV systems to achieve finite  .
 
Cuttoff

“The information capacity of a 4D sphere with radius   and time window   is given by:”

 

where   and   determines the number of bits per mode.

References

  • Nielsen, M. A., & Chuang, I. L. Quantum Computation and Quantum Information.
  • Braunstein, S. L., & van Loock, P. Rev. Mod. Phys. 77, 513 (2005).
  • Cywiński, Ł., et al. Phys. Rev. B 77, 174509 (2008).
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