I'm running into some issues trying to make sense of both my planet's density (it's given properties should make the planet an ocean world, so I'm looking for lighter elements so the planet is rocky) and the origin of its exotic magnetic field (exotic as in concentric spheres that rotate along approximately the planet's axis in alternating directions, so that floating islands can be fixed on certain points at different altitudes and move with it) and so I thought of creating an element with custom properties to explain both phenomena, but of course, the periodic table is already pretty filled up, specially with regards to the lighter elements, so this new element of mine would have to be a new heaviest element in order to fit with the table. So I though about the possibility of alternate versions of existing elements, i.e.: an alternative oxygen with similar atomic properties that behaved exotically when bonded to iron, making alternate iron oxide float. But how to explain these alternate elements?

In this post, Mranderson asks something somehow similar. I, at first, thought about using quasiparticles or elementary particles to explain the alternate elements, but as Loren Petchel pointed out on their response, having unstable, high energy elementary particles which are also heavier wouldn't be good building bricks for something intended to last.

And so I'm left with this:

Is there any way to explain alternate elements (or exotic behaviour of elements) in a more or less scientific way?

I'm trying to flesh out my world's base as scientifically accurate as I can before I get to designing it's magical aspect. Of course I can always use the "because magic" card when not able to explain something logically, but I'd like to avoid this if possible.

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    $\begingroup$ They call 'heavy water' "heavy" for a reason. It is mot made up of 'new elements. same old hydrogen and oxygen, but different isotopes. $\endgroup$ Mar 29, 2021 at 15:28
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    $\begingroup$ Concentric, nested, spherical magnetic fields? Sorry, but magnetism simply does not work that way. $\endgroup$
    – PcMan
    Mar 30, 2021 at 5:38
  • $\begingroup$ @PcMan I am aware of that, calling it an "exotic magnetic field" is just for convenience's sake and because of the planet species' context. Call it magic pseudo-magnetism if you will $\endgroup$ Mar 30, 2021 at 9:23
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    $\begingroup$ Ah, so you are recreating Pandora, from Avatar? $\endgroup$
    – PcMan
    Mar 30, 2021 at 9:26
  • $\begingroup$ @PcMan oh god, am I? That would be a pretty terrible realization $\endgroup$ Mar 30, 2021 at 9:37

4 Answers 4


If your goal is to explain why certain island floats, don't go in deep details as explaining the chemical composition: not everybody is into chemistry, and not even those who are want to know the chemical composition of particular elements of a world.

Look at Studio Ghibli's Laputa: Castle in the Sky:

Sheeta's amulet is made of hikōseki (飛行石, "levitation stone") crystal ("Volucite" or "Aetherium" in English-language releases), a material used to keep Laputa and the other flying cities aloft.

No details are given on the chemical composition of the Volucite, it's just said that every stone contains a tiny amount of it and that it quickly degrades when exposed to air, therefore refining it into a stable crystal is quite complex. Nothing more.

And this doesn't take anything away from the story.


Magnetic monopoles. They're not an "element" per se (what they are supposed to be is a little mysterious; they were theorized widely but fashion seems to have turned against them.) The system of "shells" of magnetic fields is extremely hard to justify if the atmosphere isn't plasma, unless we throw in something like this that shakes up our assumptions about how magnetic fields work. Maybe the monopoles can bind to the nuclei light elements and be part of the atmosphere itself - once you have an atmosphere crowded with, say, north magnetic poles, it seems like you can handwavily justify many weird effects. (Most speculation about monopoles was that they didn't interact with matter - you could push an asteroid and find monopoles from its center left behind - but I'd love to hear a physicist explain why a nonexistent particle can't possibly interact with strong or weak nuclear forces)

Just do it with mundane science. The oceans were stripped down to almost nothing because the star emitted lots of XUV flares. The magnetic fields are caused by immense particle beams shot between a global network of towers left anchored in the planet by previous alien inhabitants who wanted to beam power and provide support for habitations throughout the atmosphere and low orbit.

Dark matter. No one really knows what dark matter is. It doesn't interact with normal matter except by gravity and it is thought probably to move around very quickly. But what if a natural or artificial phenomenon in your planet or in your broad region of space has caused dark matter to start coupling with ordinary matter? Then it has some by definition unpredictable interactions with other particles. Maybe it ends up in nuclei; maybe it becomes stabilized in a ring system inside the atmosphere that only very faintly interacts with physical matter but has some odd magnetic effects.

Antimatter. Okay, this one is a little loony ... honestly they all are ... but some people think antimatter could be anti-gravity. The only problem is that the tiniest speck of it will blow up and kill everybody. But ... what if there is some unknown physics that can allow matter and antimatter to coexist? A field of some sort, deployed in your sector of space by an ancient civilization to defend against military attack, affects the mass of particles and antiparticles in opposite directions, and now they have different Compton wavelengths and they can't neutralize or something. (Like I said, it's a bit loony, but sci-fi is a playground! Niven got away with worse...)

  • $\begingroup$ In a similar vein, anyons might work... The details surpass me, though! $\endgroup$ Mar 29, 2021 at 15:39
  • $\begingroup$ From this content I'm not sure they are going to be useful here - the people writing it seemed fairly confident they were two-dimensional quasiparticles. $\endgroup$ Mar 29, 2021 at 16:15
  • $\begingroup$ Plektons then? With some phlebotinum thrown in, anyway... $\endgroup$ Mar 29, 2021 at 16:21
  • $\begingroup$ Well, here's the arxiv search ... good luck... $\endgroup$ Mar 29, 2021 at 17:29
  • $\begingroup$ Anitmatter will only blow up if it comes into contact with regular matter. If you have an entire region of space composed solely of antimatter, it should be just as stable as our matter-based region. (We have reason to believe that such does not exist, since the border region between the matter and antimatter regions would be very violent, and we'd probably detect that, but maybe it's just too far away to see it?) $\endgroup$ Mar 30, 2021 at 15:46

You say "floating islands". Do you mean in air or in water?

Because a floating island on water is possible with known physics. Pumice floats. If somehow you have a large enough mass of it to support your island you can have a floating island.

  • $\begingroup$ Air, but they wouldn't "float" per se, as I state in the post they'd be attached to a certain point in the magnetic field, which would rotate along the planet's axis. So is not a matter of making the islands lighter than air. $\endgroup$ Mar 30, 2021 at 9:20

Short answer: yes.
But we need to get a bit technical why.

In modern particle physics, "particles" arise as a result/manifestation of quantum fields. These fields are the most fundamental physical entities we currently understand or claim to exist. The symmetries and interactions of these fields give rise to the particles, forces, and physical nature of our universe.

If there's a deeper or better model/explanation, we don't know it yet or its speculative and unproven.

Why does this matter? Because the atoms, forces, and properties, in our universe come into existence because of these quantum fields. At least one field was deduced to be "maybe existing" to make the rest of them work - and it naturally brings its own particle to the game (the Higgs Particle/Boson).

If another field existed, then it would allow for its own novel particles and interactions to exist. It could radically change behaviour at certain energies ("symmetry breaking", allows stuff like superconductivity to happen, on a macro scale, as well as the visible universe to exist!). We would have new extra Interactions, maybe new extra forces and new ways things can combine or interact (on similar or larger or smaller scales than we currently know of), and existing ones would change. Perhaps subtly, perhaps not. Both are possible.

In fact "dark matter" is widely suspected to be undetectable directly at present, simply because its some novel particle/s, and its laws mean it doesn't interact with most things, so we have very few ways to directly detect it. There could be a whole family of dark matter particles, we just don't know. There could be entire "new" interactions we've never seen, or which only occur visible to us in certain very limited circumstances, and crucially, they could be radically different to those we're used to. I'm going to use that approach, and speculate on a similar mechanism to answer your question.....

Proposed solution

Suppose a new quantum field existed or was undiscovered so far, with some appropriate properties. This is very likely, and not entirely fanciful, but its effects could be.... well, that's up to you to devise. Its properties mean that one or more new particles may also exist. (They might also mean that existing particles can achieve novel states.)

Note that you want it to not fundamentally disrupt existing outcomes, as it takes exceedingly little change to the known laws/interactions, to destroy the fabric on which life as we know it depend. You want it just to add to the possibilities. That's probably possible (a new field wouldn't have to interact in damaging ways, or at all, with known fields) and certainly handwave-able.

If the field allows for new particles, they may not be readily detectable at present. We aren't noticing them. These new particles could have suitable properties so they can combine within the atomic nucleus and create a nucleus with fractional charge, and allow fractional negative charges around it - apparently our belief that charge can only be an integer within a nucleus or in its valence shells is only valid for a Standard Model that excludes this newly discovered field. So you'd have new elements slotted in between, in addition to the current (integer proton count) ones.

Alternatively the field could allow new particles that can combine within an existing ordinary atomic nucleus, without affecting its electrical charge or disrupting the nucleus stability, but now the nucleus has some changed or extra property.

You now have all the physics mechanism needed for your question! Quantum fields can do stuff like that. Handwave some details away, but the hard core should be valid.


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