This is an interesting article, although I’m not sure I understand all of the ramifications of it.
The link between general relativity and electromagnetism becomes clear by assuming that the so-called four-potential of electromagnetism directly determines the metrical properties of the spacetime. In particular, our research shows how electromagnetism is an inherent property of spacetime itself. In a way, spacetime itself is therefore the aether. Electric and magnetic fields represent certain local tensions or twists in the spacetime fabric.
It means that the material world always corresponds to some geometric structures of spacetime. Tensions in spacetime manifest themselves as electric and magnetic fields. Moreover, electric charge relates to some compressibility properties of spacetime. Electric current seems to be a re-balancing object, which transports charge in order to keep the spacetime manifold Ricci-flat.
https://sciencex.com/news/2021-07-electromagnetism-property-spacetime.html
Broad Speculations 
Fascinating. I certainly do not understand the details, but the ideas are both novel and seemingly plausible.
On Fri, Jul 23, 2021 at 9:48 AM Broad Speculations wrote:
> James Cross posted: ” This is an interesting article, although I’m not > sure I understand all of the ramifications of it. The link between general > relativity and electromagnetism becomes clear by assuming that the > so-called four-potential of electromagnetism directly determ” >
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I don’t really understand any of this on a technical level, but it does make intuitive sense that physics will be reducible to geometry and that geometry will be reducible to some inevitable and timeless abstract principle. (Of course, the universe is under no obligation to conform to my intuitions.)
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Not sure what to make of this. The lead author tweeted a link to the paper and pinged Sean Carroll (and Elon Musk), thanking Carroll for his book, but didn’t note which book or what the relation might be.
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“he theory predicts that strong currents can manipulate the spacetime locally, could be useful in aerospace engineering”
Haven’t there been a bunch of propulsion systems proposed usually by crackpots that involved electromagnetic coil and fields?
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There’s the EmDrive, which keeps getting knocked down by experiment but resurfaces every few years. There was even a NASA scientist pushing it for a while.
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This also from a NASA study which is different from the EmDrive, I think..
A new “propulsion” concept has been developed based on a proposed resonance between coherent, pulsed electromagnetic wave forms and gravitational wave forms (or space-time metrics). Using this concept a spacecraft “propulsion” system potentially capable of galactic and inter-galactic travel without prohibitive “travel times” has been designed. The “propulsion” system utilizes recent research associated with magnetic field line merging, hydromagnetic wave effects, free-electron lasers, laser generation of megagauss fields, and special structural and containment metals. Research required to determine potential, field resonance characteristics and to evaluate various aspects of the spacecraft “propulsion” design is described.”
The field resonance “propulsion” concept has been developed utilizing recent research into the causes of solar flares, magnetic substorms, black holes, quasars, and UFOs. The concept is based on two assumptions: (1) Space-time is a “projection” of a higher dimensional space in much the same way that a hologram is a projection or a subset of our space-time reality, (2) A relationship exists between electromagnetic/hydromagnetic fields and gravitational fields – that is, Einstein’s long sought for unified field theory can be developed.
link:https://ntrs.nasa.gov/api/citations/19800010907/downloads/19800010907.pdf
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Looks like quite the paper. He manages to reference UFOs, galactic travel, parapsychology, higher dimensions, and a whole slew of scientific sounding buzzwords. It’s so over the top, I have to wonder if it’s a joke.
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This paper (the one that is the topic of the post), however, does make one clear prediction that I don’t think I have seen before: that light will bend in a strong EM field.
It also seems to tie EM and gravity to the structure of space time. One thing that has never made much sense logically to me is why we would see the speed of light in the famous Einstein equation that shows how matter and energy relate.
In a broader view, if the EM field theories of consciousness are on the right track, this also seems to suggest a novel panpsychism.
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I know physicists have been trying to find a way to unify the forces for a long time. Reportedly the EM force and weak nuclear force have been unified into the electroweak force for very high energy levels, but the rest has remained elusive. Gravity (and spacetime) have so far remained stubbornly separate from the others.
So the paper’s assertions seem revolutionary if true. I came across the author’s tweet because I was searching for commentary on their paper from any other physicists. Nothing yet, even from Carroll, despite the ping.
But light is an EM wave, so its path being affected by a strong EM field doesn’t seem striking to me. And GR already accounts for high energy levels (including mass) warping spacetime. But I might well be missing something.
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I haven’t seen any prediction of light waves bending in an EM field. If photons had a charge, it would be logical but not so much since it doesn’t have charge.
Of course, most of the math is beyond me, but it seems like Weyl and Wheeler were both on this same general path before this paper.
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Sometimes we don’t understand things, not because there’s anything missing in us, but rather because of what’s being said itself. I think that might be the case for this one. Electromagnetism might be a property of spacetime? Don’t we already believe that all of reality happens to be a property of spacetime? (And personally I’m open to dimensions beyond the four that we idiot humans don’t happen to perceive in general, but whatever on that for now.)
Regardless just because this doesn’t seem to be a full on Sokal hoax, that doesn’t mean the same instruments can’t be used to write a successful paper that says very little if anything. In fact I think those instruments are used in some capacity virtually every time. If anything is being said here that’s not already understood, then in plain English I’d like to know what those things happen to be.
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Don’t you think it might be sort of cool if the stuff of mind (EM) and the stuff of matter (gravity) might be directly tied to the form of space time?
🙂
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You know I think that would be cool James! And I apologize for coming off arrogantly here. My point however is it seems to me that this paper could be pulling a fast one, or passing something off as an extraordinary claim when in simple reduced form that supposedly extraordinary claim is something we already believe. And it could be that I’m wrong about this. Maybe there actually is a novel idea hidden in this paper that eludes me in its current form. If so then I’d love someone to explain it to me in a way that I’m able to understand.
Anyway as I see it, time, space, and perhaps others that we don’t grasp, reside as dimensions of existence itself. Stuff makes no sense without them in some capacity. So from this perspective what we call electromagnetism does happen to be an element of spacetime, as well as gravity, matter, and all else including conscious things like us. For example where it says “Electric and magnetic fields represent certain local tensions or twists in the spacetime fabric” one might reply, “Yep, that’s also under the heading of ‘causality’”. Similarly, I represent certain local tensions or twists in the aether of spacetime. That’s currently my interpretation anyway.
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The novelty is this: Since water waves need water and sound waves need a physical medium, once they realized light was (or acted like) a wave, the assumption was there must be a medium, which they called aether. But the famous Michelson–Morley experiment seemed to rule that out, and light was seen as wave-like (and also particle-like, which is freaky), but did not need a medium (also a little freaky).
This paper is essentially saying that the fabric of spacetime is is long-sought aether. It was there all along, right under our noses.
It’s an interesting idea with some unifying potential, but it seems to leave the weak and strong forces dangling. As Mike mentioned, we do have electro-weak unification, and as boson-mediated forces, the EM, weak, and strong, do seem related. So it’ll be something to see what comes of this.
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Thanks Wyrd, that is deep! Just as water particles exist as the medium for water waves, here they’re proposing that spacetime itself might exist as the medium for general electromagnetic radiation? I wonder if this is a falsifiable proposal?
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In the article they wrote, Lindgren and Liukkonen write:
I kinda wonder about places like CERN or others that use high-powered superconducting magnets. Might such effects be apparent there? If charge and current flow are somehow associated with rebalancing the flatness of space, do our simple devices participate in this? If so, why haven’t we seen it (or do we)? If not, what explains this apparently separate use of charge and current?
I skimmed their paper, and this might be just playing with numbers based on similarities between basic physics equations (Einstein’s and Maxwell’s, in this case). OTOH, there magnetism is as pervasive as gravity, and the magnetic structure of the universe, both large and small scale, is extremely complex. It would not be at all surprising gravity, spacetime, and magnetism, are linked in fundamental ways.
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Wyrd,
Thanks for your comments. You probably have better insight into this paper than I do.
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One other thing. I have noticed a number of people saying the paper is wrong or can’t be right. I’m not completely clear if these people have done anything more than a cursory look at it or whether they have actually found a flaw.
There is also a Reddit on it.
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