# Does gravity have anything to do with Van Der Waals forces?

Does gravity have anything to do with Van Der Waals forces? Just throwing this out there, I was wondering if they do because gravity is such a weak force and the VdW forces at the molecular level could seem to be a good intermediary force between gravity and the forces acting within atoms. Given that there are so many atoms and molecules within objects like the earth doesn't it seem possible that an extrapolation of the VdW forces could make a good candidate for a theory of gravity?

No. Van der Waals forces are electromagnetic, not gravitational. "Van der Waals forces" are actually a family of different effects. Dipole-dipole Van der Waals falls off as $1/r^7$ (non-retarded) or $1/r^8$ (retarded). These forces can be understood using only electromagnetism and quantum mechanics. Gravity is unnecessary in their explanation, and gravitational forces fall off as $1/r^2$.

Gravity accelerates all objects equally, whereas the magnitude of Van der Waals forces depends on the polarizability, which varies from material to material. They are not similar and neither can explain the other.

• Really nice answer. Sep 26 '20 at 19:08
• Naively, I suppose that's the case. Feb 9 at 5:08

An author called Zhang has indeed suggested they are related: https://arxiv.org/abs/1303.3579. As Zhang alludes to, "dark energy" is basically the new cosmological constant.

And I have seen other work by an author called Dmitriev - https://arxiv.org/abs/physics/0611173 - that suggests gravity is experimentally dependent on temperature - which Zhang relies on in theory.

I'm not endorsing these authors' work but I can't seem to find anything that criticises them.

• I read that one, awesome stuff. Feb 9 at 5:07

There is a connection. According to

R.L.Jaffe (2005). "The Casimir Effect and the Quantum Vacuum". Physical Review D. 72 (2): 021301. arXiv:hep-th/0503158.

the Casimir force is simply the (relativistic, retarded) van der Waals force between the metal plates.

Another interpretation of Casimir force is that it is due to quantum vacuum. That same vacuum is said to produce inertia, according to

Inertia as a zero-point-field Lorentz force, Bernhard Haisch, Alfonso Rueda, and H. E. Puthoff, Phys. Rev. A 49, 678 – Published 1 February 1994

and later

Inertial mass and the quantum vacuum fields, Bernard Haisch, Alfonso Rueda, York Dobyns, First published: 26 February 2001, Annalen der Physik, 10 (5), 393, 2001

With the principle of equivalence the connection to gravity appears. Some of the authors also wrote papers on that subject later.