Impact on Spaceflight Operations

For decades, physicists have understood fundamental forces like electromagnetism and gravity as being mediated by quantum fields and virtual particles, such as photons and gravitons. At the same time, some forces in nature—like pressure in a gas—emerge not from fundamental interactions but from thermodynamic principles, driven by entropy and free energy.

We’re taught that gravity is a fundamental force, like electromagnetism, and that it’s carried by hypothetical particles called gravitons. This is the standard view in physics, especially in quantum gravity research.

But what if gravity isn’t fundamental at all? What if it’s more like pressure in a gas—something that emerges from the collective behavior of microscopic systems trying to reach thermal equilibrium? This idea, called entropic gravity, has been around for a while, but until now, it lacked a solid quantum foundation.

Can we build a fully quantum model where gravity emerges from entropy and thermodynamics, rather than from fundamental particles like gravitons? And if so, how would we test it?

Yes—and that’s exactly what this paper does. The authors construct detailed quantum models where gravity arises from the behavior of qubits or oscillators interacting with a heat bath. These systems naturally produce a force that looks like Newton’s law of gravity—not because of graviton exchange, but because the system is trying to minimize its free energy. Even better, the models predict subtle differences from standard gravity, like tiny amounts of noise and decoherence, which could be detected in near-future experiments.

On the Quantum Mechanics of Entropic Forces

Daniel Carney^1,*, Manthos Karydas¹, Thilo Scharnhorst^1,2, Roshni Singh^1,2, and Jacob M. Taylor

https://journals.aps.org/prx/abstract/10.1103/y7sy-3by1

Impact on Spaceflight Operations

In the entropic gravity framework described in the paper, gravity emerges from the thermodynamic behavior of a mediator system (like qubits or oscillators) interacting with massive bodies. Therefore, entropic gravity can decrease when conditions reduce the entropy gradient or disrupt the thermal equilibrium that drives the force.

Factors That Decrease Entropic Gravity

1. Lower Temperature of the Mediator System (T):
   • The entropic force is proportional to ( T^2 ), so reducing the temperature directly weakens the force: $ F_{\text{entropic}} \propto T^2 $
   • In cold environments or cryogenic conditions, the entropic contribution to gravity becomes smaller.
2. Reduced Coupling Between Masses and Mediators:
   • If the interaction between the masses and the mediator system weakens (e.g., smaller coupling constants like ( l )), the entropy gradient becomes less sensitive to mass positions.
   • This leads to a weaker entropic force.
3. Increased λ Parameter (Nonlocal Model):
   • In the nonlocal model, the function ( f(x) ) includes a term: $ \frac{1}{f(x)} = \lambda + \frac{l^2}{|x|} $
   • A large λ suppresses the position-dependent part of the force, effectively reducing entropic gravity.
4. Disruption of Thermal Equilibrium:
   • Entropic gravity relies on the mediator system being in thermal equilibrium.
   • Rapid motion (e.g., fast acceleration, rotation, or vibration) can push the system out of equilibrium, reducing the entropic force temporarily or introducing noise.
5. Sparse or Low-Density Mediator System:
   • Fewer qubits or oscillators mean less entropy to drive the force.
   • In the local model, increasing the lattice spacing ( a ) reduces the density of mediators, weakening the gravitational interaction.
6. Chemical Potential Tuning (Local Model):
   • Specific values of the chemical potential ( \mu ) can suppress the internal energy contribution, and in some regimes, reduce the overall force.
7. Quantum Decoherence or Noise:
   • If the mediator system becomes noisy or decoheres due to environmental interactions, the entropic force may become less coherent or weaker.

Summary

Entropic gravity decreases when:

• The system is colder,
• The coupling is weaker,
• The mediator is sparse or poorly thermalized,
• The λ parameter dominates over position dependence,
• The system is driven far from equilibrium.

🌀 Does Rotation Reduce Entropic Gravity?

Short answer: Not directly—but it can affect the local thermodynamic conditions that determine the strength of entropic gravity.

Why Rotation Might Matter in Entropic Gravity

1. Thermal Equilibrium Assumption:
   • Entropic gravity arises from a mediator system (qubits or oscillators) that must remain in thermal equilibrium.
   • Rotation introduces non-equilibrium dynamics (e.g., centrifugal forces, shear, turbulence), which could disturb the mediator system.
   • If the system is driven out of equilibrium, the entropic force may decrease or fluctuate, depending on how well the system re-thermalizes.
2. Local Entropy Gradients:
   • Rotation can redistribute mass and energy, potentially altering local entropy gradients.
   • Since entropic gravity is driven by gradients in entropy, this redistribution could change the direction or magnitude of the force.
3. Decoherence Effects:
   • The paper discusses how spatial superpositions and motion can cause decoherence in the entropic model.
   • Rotation might enhance decoherence effects, especially in the local model, where each mass interacts with a lattice of qubits.
   • This could lead to additional noise or damping in the gravitational interaction.
4. Adiabatic Limit Violation:
   • The entropic force assumes slow, adiabatic motion of masses.
   • Rapid rotation or thrust changes could violate this assumption, leading to transient deviations from Newtonian gravity.

Summary

• Rotation doesn’t reduce gravity directly, but it can disturb the thermal mediator system that gives rise to entropic gravity.
• This could lead to fluctuations, noise, or reduced force if the system is pushed out of equilibrium.
• In practical terms, for a rocket launch, these effects are likely very small unless the rotation is extreme or the system is engineered to be sensitive to entropic effects.

Rotation is quite common and may be an inherent behavior of objects traveling through space. Perhaps there is another fundamental constant yet to be discovered.

Rotational Dynamics and Vorticity Across Scales: A Unified Literature Review of Fluid Helicity, Cosmic Structures, and Optical Angular Momentum (OAM)