Exploring entropy gradient propulsion via the Casimir Effect
I’m exploring a concept for a new type of propulsion system. In this system, the hull of the spacecraft is constructed of a special metamaterial and is itself the “engine” that propels the craft. The concept is explained in more detail in the following paragraphs. I am seeking critical feedback.
The metamaterial is essentially a “stack” of Casimir cavities. Each cavity consists of a tunable dielectric material sandwiched between two conductive layers. The stack would contain as many cavities as is practical with existing semiconductor manufacturing techniques.
I realize, of course, that a Casimir cavity produces a very, very small force (microscopic), but we’re not interested in the force produced. Instead, we’re interested in the suppression of vacuum fluctuations inside the cavity.
This region of suppressed vacuum fluctuations will have a much lower entropy than the surrounding space. By “stacking” or “layering” of these cavities we can greatly increase the size of this low entropy zone.
The low entropy region will not extend very far beyond the hull, but will form a thin boundary layer much like the low pressure region formed on the top of an airfoil as described by Bernoulli’s Principal.
According to Erik Verlinde’s theory of emergent gravity, the surrounding high entropy space will “push” on the low entropy region of the spacecraft in an attempt to equalize the entropy of space-time.
Another way to think of it is the spacecraft “falls” into the low entropy trough created by the region of suppressed vacuum fluctuations. This is an entirely new concept of propulsion that does not require thrust or a reactionary force as described by Newton’s third law. As such, conventional equations to calculate force based on mass do not apply here.
The craft is “steered” or “controlled” by moving this region of low entropy around the hull of the craft. The craft will move in the direction of the low entropy zone.
This control is accomplished with a pulsed magnetic fields. The dielectric layer of the Casimir cavity is made from a material whose permittivity is tunable by the magnetic field. By changing the permittivity of this layer, the suppression of vacuum fluctuations in the Casimir cavities may be increased or decreased as needed.
That’s the concept in a nutshell.
I know it’s highly speculative, but I have researched suitable dielectric materials with permittivity that respond well to magnetic fields and the metamaterial could be constructed using existing semiconductor manufacturing techniques. Power requirements to drive the electromagnetic coils would be in the kilowatt range.
I am hoping for some constructive feedback from a technically literate community. I would love to hear your thoughts.
From the linked publication: “A localized suppression of vacuum entropy near the hull creates dS/dx > 0 outward”.
I don’t understand this part. My naive view is that localized suppression means S<S0 (surrounding entropy), or some local minimum. S0 is the same on both sides far away from this minimum. This means the gradient dS/dx is positive on one side of this localized suppression region, and negative on the other side, possibly in an asymmetrical way. But after you integrate dS/dx over x to calculate the total force acting on the region, it will be exactly 0. The same reasoning applies to the other side of the craft, where you have a local peak of vacuum entropy. The total “push” will be 0 + 0.
Mike, thank you so much for catching that error! You are absolutely right. That is describing the situation where a “static” magnetic field is used to suppress vacuum fluctuations in both the front and the back of the craft at the same time and that is not what we want. As you point out, that will not result in the asymmetry we require.
In order to get an asymmetric dS/dx profile we would only suppress the vacuum fluctuations in the front of the craft and leave the back “off”. We’d also need to apply a “pulsed” magnetic field to the front—not a “static” magnetic field. I tried to show this in my simple diagram, but I didn’t do a very good job of conveying that idea.
I am grateful that you caught my mistake. It’s been 45 years since I did any calculus so my math skills are really rusty. It may take me some time to work out the correct equations, but this kind of feedback is invaluable. This is exactly what I’m looking for. What I was hoping for.
Thanks again!
From my understanding of your description, your proposed propulsion violates conservation of energy and momentum.
This is a vague wordy description. Discussing topics that are highly unituitive and poorly understood. (Casimir effect, entropy of vacuum) And claiming that something breaks conservation of energy.
This is multiple clear signs that you are mistaken.
If you come back with detailed equations for exactly how this might work, I’m pretty sure there is a proof of energy conservation in quantum field theory. So if you have a proof that this works in quantum field theory, you have a maths contradiction. But at least looking for the error is a clear and specific task.
If you have a new theory of fundamental physics, please explain what this theory is.
(I was making an extremely similar mistake about 9 years ago. )
Thank you for your comments. I really appreciate you taking the time to read through my theory.
This propulsion system won’t work like traditional systems that rely on a reaction mass and, therefore, conservation of momentum. Instead it will work more like reverse osmosis.
In the reverse osmosis analogy, the “solution” is space-time and the “solute” is the vacuum fluctuations. In osmosis, the solution will try to equalize the concentration of solute. In doing so, it will set up a gradient that will cause a “push” from space-time as it tries to equalize the concentration of vacuum fluctuations.
Or we can think of it in terms of thermodynamics, where a system tends to proceed from low entropy to high entropy. If we can create a low entropy zone (fewer vacuum fluctuation modes), then higher entropy space-time (many more possible vacuum fluctuation modes) should try to bend around it, and in doing so provide the “push” needed by our propulsion system.
I realize the forces produced by the Casimir effect are very, very tiny, but I’m not depending on a force like traditional propulsion systems that use a reaction mass. I’m relying on entropy gradients to provide the “push”.
Here is a link to a white paper I wrote with some minimal supporting math: https://archive.org/details/entropy-gradient-propulsion-system-whitepaper-rev-c
Here’s a link to a more simplistic overview of the concept (no math): https://archive.org/details/entropy-gradient-propulsion-overview
I’ve been scouring the internet looking for other people exploring similar ideas and have found a couple different guys. Dr. Harold White (formerly of NASA) and Charles Chase (formerly of Lockheed-Martin Skunkworks) are both exploring propulsion systems that leverage the Casimir Effect. I’ve reached out to them and am waiting to hear back. Here are links to their website: https://casimirspace.com/ and https://unlab.us/
Thanks again for your interest in my idea.
Reverse osmosis devices are used to make fresh water. They also conserve momentum.
Conservation of momentum isn’t just how conventional rockets work. It’s a law that we suspect applies universally and without exception.
Wordy analogy based reasoning of this kind does not reliably produce correct answers.
At best, reasoning like this can be used to generate a suggestion for what equations to consider. Because if the upside is a nobel prize, and the downside is wasting a few hours, it’s worth a go even if it’s probably wrong.
This relies on a person that understands the maths of quantum field theory.
In practice, there are a lot of people going “I have the ideas, I just need someone to add the maths”, and not that many people who understand the maths.
Looking at your equations, I think I can spot at least 1 mistake.
You say F=TdSdx from “Verlinde’s entropic gravity”. Verlinde’s work isn’t something I am familiar with, so I can’t say whether this is correct or not.
But, if it is, this is the force at 1 point. To calculate the overall force, we must take the integral.
If S tends to a constant (the background entropy of empty space) sufficiently fast as the distance from your spacecraft increases, then we can use the gradient theorem https://en.wikipedia.org/wiki/Gradient_theorem to show that all the forces must inevitably cancel out.
Consider this diagram.
The entropy needs to be the same at the far left and far right of the graph, because empty spacetime, far from any influence, has a fixed entropy. Your spacecraft sits in the middle. A small amount of your spacecraft on the far left experiences a steep gradient, and so a strong rightwards force. A larger amount of your spacecraft in the middle and right experiences a weaker leftward force.
And so it all adds up to 0 force in total.
This sort of everything cancelling out behavior is an inevitability assuming the equation F=TdSdx and
Flat spacetime
T and S are converge to a constant (and do so at least cubically fast, 2x the distance means at most 1⁄8 th as much variation in T and S.)
Donald, thanks for taking the time to explain this to me. I can see now why this won’t work.
I can’t thank you enough for patiently explaining the errors in my reasoning. Your thoughtful analysis is exactly what I was hoping for.
I had suspected that if it were this easy someone else would have surely thought of it by now and pursued this angle. And now I know why they didn’t.
I’ll leave this stuff to the physicists and mathematicians and get back to renovating our old house—I know that would certainly make my wife happier!
I don’t know the precise form of Verlinde’s theory, but assuming it’s correct, would this be the right shape for it anyway? It sounds like you’re basically suggesting an air balloon of sorts, where the lower density of air is replaced by lower density of entropy. But with a balloon, the effect works because there is a pressure gradient in the atmosphere, and it produces an upward force. What would be the symmetry-breaking feature in this idea?
More interestingly though, if this was right, scoping it out might be a way to test Verlinde’s theory somehow, which would in itself be useful enough. But the fact that it hasn’t been done yet suggests that it’s not trivial (e.g. maybe you can’t achieve density differences able to produce a measurable effect with reasonable apparatus sizes).
Thanks for your comment!
Yes, the hot-air balloon and temperature/pressure gradients is a good analogy. The balloon floats through a fluid medium (air), the entropy propulsion craft floats through the entropy structure of space-time. Both are pulled into regions of lower potential, but in our case, the craft itself is creating the region of lower potential and it’s entropic—not thermal.
I’ve managed to find at least one person, Dr. Harold G. White, that is actually manufacturing Casimir “stacks” using semiconductor technology, but at the moment he’s concentrating on using the Casimir effect to produce power (batteries).
His laboratories would probably be in the best position to support experiments to detect changes in entropy that would likely manifest as tiny forces or weight changes in the sample. Sensitive torsion balances or laser interferometry would be needed to detect these changes.
The effect can be enhanced or controlled by exposing carefully chosen dielectric materials to magnetic fields. I have written to Dr. White, but have not heard back from him. I have also put this idea in the public domain by publishing a white paper to archive.org.
I am not smart enough to make this happen, but I know there are people out there who can. I am just anxious to get the idea out there where these physicist can take the ball and run with it, so to speak. I would love to see this happen in my lifetime.
So looking at the theory more in detail, I am not convinced this works very well. Generally speaking, Verlinde’s theory doesn’t seem very well accepted and is taken more as speculative (and Verlinde’s own paper from 2016 about emergent gravity seemed to shift the focus a bit away from just entropy), but also, as far as I can tell, the problem is what is the main entropy contribution from a given region of space. And in Verlinde’s derivation, he makes that to depend on all information that describes entirely that region. That’s what the holographic principle means after all. Really basically his idea seems to be that, given a certain amount of matter, the configuration where those bodies are closer is higher entropy than one where they aren’t; so the universe tends to bring them together.
The problem is that as far as I can tell there’s no clear idea of how that would work out in more complex configurations of matter, and in fact that seems to be one of the main criticisms of Verlinde’s theory; and if it’s just an explanation of gravity, it shouldn’t allow repulsive forces, which would instead be necessary for any kind of engine to work (otherwise you’re not flying… you’re just falling with style).
Also the scales involved will be dominated by Mc2 terms (all the energy of the rest mass of the configuration of matter which is distributed among the degrees of freedom encoding it on the holographic boundary), so honestly odds are anything you can do with the Casimir effect is trivial by comparison.
Thank you for your comments. I really appreciate your honest assessment.
I know the forces produced by the Casimir effect are very, very tiny, but I’m not depending on a force like traditional propulsion systems that use a reaction mass. I’m relying on entropy gradients to provide the “push”.
I tend to compare emergent gravity to osmosis, where space-time is the “solution” and the vacuum fluctuations are the “solute”. In thermodynamics, systems tend to proceed from low entropy to high entropy. If we can create a low entropy zone, then higher entropy space-time should try to bend around it, and in doing so provide the “push” needed by our propulsion system.
Here is a link to a white paper I wrote with some minimal supporting math: https://archive.org/details/entropy-gradient-propulsion-system-whitepaper-rev-c
Here’s a link to a more simplistic overview of the concept (no math): https://archive.org/details/entropy-gradient-propulsion-overview
I’ve been scouring the internet looking for other people exploring similar ideas and have found a couple different guys. Dr. Harold White (formerly of NASA) and Charles Chase (formerly of Lockheed-Martin Skunkworks) are both exploring propulsion systems that leverage the Casimir Effect. I’ve reached out to them and am waiting to hear back. Here are links to their website: https://casimirspace.com/ and https://unlab.us/
Can you use this to keep the lights on forever? E.g. fly the craft in a circle and have it hit a waterwheel on every go.
Haha. Yes, I had considered the possibility that this concept could be applied to power generation as well.
Multiple Casimir stacks could be arranged on a “rotor” such that the entropy gradient would cause the rotor to spin. The rotor could be attached to a generator via a direct drive or reduction gear coupling.
And there are likely other applications that have yet to be imagined.
I feel very fortunate to have found this forum. This is exactly the type of fertile environment in which these “seeds” can grow and flourish.
I’m excited to see where these discussions can take us. Thank you so much for your enthusiasm! I look forward to a continued dialogue.
Couldn’t you just steer by rotating the craft with a gyroscope?
Thanks for your comment. I appreciate your interest.
That is a fascinating suggestion. This would greatly simplify the design. The low entropy region of the craft could remain fixed, say in the bow of the craft and the gyroscope would be used to rotate the craft and point the bow in the intended direction of travel.
This is certainly worth considering. Thank you for your thoughtful suggestion.