Force Born from Heat and Uncertainty express

Original: "Uncertainty Principles and Maximum Entropic Force"
· Jonas Mureika, Elias C. Vagenas
arXiv:2605.07992 · 2026-05-08 · CC BY 4.0 · 2 min
Quantum corrections alter the force with which information pushes matter when space loses its sharpness.

An ice cube in a glass of water doesn't just float: it gets pushed. Water molecules bombard it from all sides, and this bombardment gives rise to a force you can measure. In physics, there's a similar force, but it acts not on ice but on anything with mass, and it arises not from molecular jostling but from information. It's called entropic force. Around a black hole, you can imagine an invisible sphere: its horizon. On this sphere, like on a screen, information about everything that has fallen inside is 'recorded.' When something approaches the horizon, the information on it rearranges, and this rearrangement pushes the object outward. That's how entropic force is born.

But what happens when the very fabric of space stops being smooth? At scales comparable to the Planck length, which is billions upon billions of times smaller than an atomic nucleus, space and time may become grainy. There, you can no longer say precisely where a particle is and how fast it's moving. The usual Heisenberg uncertainty principle breaks down, and its extended versions with mysterious names like GUP or EUP take the stage. They add tiny corrections to the familiar formulas, depending on as-yet-unknown parameters of quantum gravity. The authors of the new study took these extended principles and recalculated the entropic force using them.

The Planck area is not just a number. It's the smallest possible 'cell' of space, below which, according to some theories, nothing exists. If you imagine the black hole horizon as made of such cells, their number affects the force with which the horizon repels approaching objects.

It turned out that the force changes depending on which uncertainty model you choose. In one case, the correction depends on the particle's energy; in another, on the size of the region where the interaction occurs. And in the EUP model, the force is directly linked to how many Planck 'squares' fit on the surface in question. This is similar to how gas pressure changes with the number of molecules: the more cells on the horizon, the more noticeable the quantum gravity effect. This approach doesn't give a definitive answer as to which theory is correct, but it builds a bridge between abstract equations and what could be measured in the future.

Someday, it might be possible to detect deviations in particle motion near black holes or in the early universe. Then the entropic force, corrected by quantum uncertainty, will cease to be a mind game and become a key to understanding what space is truly made of.

You can feel entropic force yourself: when you stretch a rubber band, it heats up, and when you compress it, it cools down. This happens because the molecules inside the band rearrange, changing their entropy, and this rearrangement creates mechanical stress.

In Peter Watts's novel Blindsight, alien beings use quantum effects to manipulate information on event horizons, echoing the idea of controlling entropic forces.

Scientists
Jacob BekensteinStephen HawkingWilhelm WienSatyendra Nath BosePaul DiracEmilio Gino Segrè
Concepts
generalized uncertainty principle uncertainty principle quantum gravity grand unified theory quantum gravity probes gravitational constant Law of Universal Gravitation gauge invariance gravitational potential error threshold general relativity vacuum upper limit fundamental physics newtonian limit force entropy area law CPT theorem planck scale