Abstract
This article analyzes the differential-geometric invariants of gradient vector fields. The properties of orthogonality to level surfaces, irrotationality, and harmonicity are presented with rigorous mathematical proofs, and their interrelationships are demonstrated. Three equivalent characterizations of a conservative field in simply connected domains are proven. The dimension-dependent structure of gradient fields is determined through the fundamental solutions of the Laplace equation. The applications of the results in electrostatics, hydrodynamics, and optimization theory are discussed.
References
1. Arfken, G. B., & Weber, H. J. (2005). Mathematical methods for physicists (6th ed.). Elsevier.
2. Arnold, V. I. (1992). Catastrophe theory (3rd ed.). Springer-Verlag.
3. Batchelor, G. K. (2000). An introduction to fluid dynamics. Cambridge University Press.
4. Boyd, S., & Vandenberghe, L. (2004). Convex optimization. Cambridge University Press.
5. do Carmo, M. P. (1992). Riemannian geometry. Birkhäuser.
6. Evans, L. C. (2010). Partial differential equations (2nd ed.). American Mathematical Society.
7. Goodfellow, I., Bengio, Y., & Courville, A. (2016). Deep learning. MIT Press.
8. Griffiths, D. J. (2017). Introduction to electrodynamics (4th ed.). Cambridge University Press.
9. Jackson, J. D. (1999). Classical electrodynamics (3rd ed.). Wiley.
10. Lamb, H. (1932). Hydrodynamics (6th ed.). Cambridge University Press.
11. Mandelbrot, B. B. (1983). The fractal geometry of nature. W. H. Freeman.
12. Marsden, J. E., & Tromba, A. J. (2012). Vector calculus (6th ed.). W. H. Freeman.
13. Matsumoto, Y. (2002). An introduction to Morse theory. American Mathematical Society.
14. Milnor, J. (1963). Morse theory. Princeton University Press.
15. Schey, H. M. (2005). Div, grad, curl, and all that: An informal text on vector calculus (4th ed.). W. W. Norton & Company.
16. Spivak, M. (2018). Calculus on manifolds: A modern approach to classical theorems of advanced calculus. CRC Press.