# Dirac Field, van der Waals Gas, Weyssenhoff Fluid, and Newton Particle

## Abstract

**:**

## 1. Introduction

## 2. Dirac Field in Polar Form

#### 2.1. Dirac Spinors

#### 2.2. Polar Decomposition

## 3. Torsion Effective Approximation and van der Waals Gas

#### 3.1. General Thermodynamic Variables

#### 3.2. Massive Propagating Torsion

## 4. Zero Chiral Angle and Weyssenhoff Fluid

#### 4.1. Non-Relativistic Regime

#### 4.2. Hydrodynamics with Spin

## 5. Spinlessness and Newton Mechanics

#### 5.1. Classical Limit

#### 5.2. Point Particle

## 6. Conclusions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## Appendix A

## References

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**MDPI and ACS Style**

Fabbri, L.
Dirac Field, van der Waals Gas, Weyssenhoff Fluid, and Newton Particle. *Foundations* **2024**, *4*, 134-145.
https://doi.org/10.3390/foundations4020010

**AMA Style**

Fabbri L.
Dirac Field, van der Waals Gas, Weyssenhoff Fluid, and Newton Particle. *Foundations*. 2024; 4(2):134-145.
https://doi.org/10.3390/foundations4020010

**Chicago/Turabian Style**

Fabbri, Luca.
2024. "Dirac Field, van der Waals Gas, Weyssenhoff Fluid, and Newton Particle" *Foundations* 4, no. 2: 134-145.
https://doi.org/10.3390/foundations4020010