If the laws of conservation of energy remain the same, can I change everything else? [closed]

Question

This universe is boooring.

I don't care that today's science is basically magic, and being a programmer is the equivalent of a fantasy ''rune shaman''. I want actual magic, the type of magic people believed in before industry, before the Renaissance.

In our universe, we had steampunk, dieselpunk, and soon we live in those boring cyberpunk stories. But we never had DUNGEONPUNK, and I want to be real.

Floating castles, alchemy to turn lead into gold, psionics, telekinesis, people using magic that allows them to pass thru solid object unharmed and so on, stuff like that.

So in this new universe, if the laws that govern how energy work remain the same, can I change everything and have a functional universe?

Or maybe the correct question might be, what is the (hopefully) small list of physical laws of the universe that I can't change if I want this imaginary universe to stiff function?

Answer 1

Simple answer: change which forces & particles are plugged into energy conservation. Real physics is far more... specific than anything that idea determines.

If magnetism didn't exist and someone made it up in a story, it might seem like magic violating EC. But it doesn't violate EC: the energy of an object thereby affected has a kinetic component dependent on its speed and a potential component dependent on its position. And, with a suitable electrical power source, one can turn electromagentism on and off, and thereby update other objects' total energies. If you invent new forces by analogy with EM, you can make physics seem very different despite EC. The implications for floating castles are obvious.

Alchemy is actually real; it just uses lots of energy. How much energy depends on the finer details of how nuclei work, so feel free to reduce the energy scale to match chemistry. (That ruins otherwise amazing nuclear power, but I suspect you don't mind that.) You could make the reason it doesn't happen on its own one of needing a nuclear catalyst.

For psionics, imagine something analogous to X-ray scans that see the inside of brains, together with read/write abilities due to evolution or magic. Bones block real X-rays (which are EM radiation), but not your fake cousins of them. For telekinesis, suppose there's a "magnetism" that can work on anything, but is customisable, e.g. by mixing several forces to tune to one object.

Solid walls block us in a real-life version of this trope, but dark matter could cut through it. If dark matter has its own kind of EM to hold it in solid clumps, you could wrap yourself in a wall-bypassing cloak. (How you'd get a hold of the cloak with mechanical forces is a subtler issue; if the two kinds of EM mix a little bit, that might just be feasible without a wall being harder to pass through than swimming in treacle.)

Answer 2

New rules are not intrinsically more exciting than old rules.

/This universe is boooring./

Your problem is that you find laws and order boring. They are, too. Boring and predictable. The things you list as exciting are exciting to you because they break the rules.

If you set up new laws and new orders that are also predictable, those too will become boring. If everyone is floating thru walls with your new rules it is no more exciting than those people climbing up stairs with the current rules. New sets of rules are not intrinsically more exciting than old sets of rules.

If you consider chaos and transgression and iconoclastic wildness to be exciting, set your story in the world of ordinary rules and physics. Then when your character breaks the rule and turns poop into pure gold (that still looks like a piece of poop) it will cause excitement! If a person invents a device that allows them to accomplish things previously impossible (like flying) that too will be very exciting.

Answer 3

There’s a foundational theorem in fundamental physics called Noether’s Theorem that proves there’s a conservation law associated with every symmetry of the universe. If you want your universe to have time-translation symmetry (on the broad scale it looks the same today as it did yesterday and will tomorrow) then you have to have conservation of energy. If you want the universe to look the same wherever you go, you have to have conservation of momentum. If you want the universe to look the same in all directions, you have to have conservation of angular momentum. And so on — the less obvious symmetries of the standard model lead to conservation of electric charge, quark colour, and so on. (“Looking the same” basically means that the laws of physics look the same, not that the universe has to be completely homogenous.) (Technically speaking, the conserved item has to be described by a Lagrangian, but almost everything in modern physics is.)

Answer 4

Yes

I'm going to focus on this:

can I change everything and have a functional universe?

You can have psionics and telekinesis and magic and assert that energy conservation holds true. You can envision a functional universe with those things. Unless you are Greg Egan, you're not obligated (and frankly, not encouraged) to give the reader a rundown on the whole of physics in your magical universe.

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Even the smallest changes have far-reaching consequences. I've heard that even if little old insignificant neutrinos just arbitrarily had the interaction cross-section of an equivalent energy photon, the Sun would get about 3% brighter due to all the trapped neutrinos and its lifespan would shorten by about 500 Myr or so, which might've tipped the primordial Earth into a greenhouse state.

There are no small changes or additions you can make that don't radically alter the shape of the cosmos.

Answer 5

The rules of your universe are entirely up to you.

If you aren't writing hard SF, all you need to do is be consistent about your rules. Establish them early and don't break them later.

The rules are there to limit the characters and create suspense. This goes for both protagonists and antagonists. If the reader get the feeling that the author just invents a new super-power whenever they need one, much of the suspense is lost.

Conservation of energy is a good rule. It fits with the readers intuition of how the world works and is also a limit that can be bypassed by a clever character.

Entropy increasing is a another good rule, but one that is harder to work with. Deciding exactly what entropy means can be difficult.

Conservation of momentum is a good rule, but a very annoying one. It prohibits all sorts of fun stuff like a small person throwing really big things around.

What is magic in your universe? You need to decide that before you start writing about it.

One option is that magic is an extra form of energy, and the manipulation of that energy. There should be strict limits to how much energy a mage can handle at once.

Another option is that magic allows you to decrease entropy. This allows all sorts of fun effects, but you have to be careful to not make magic TOO powerful.

There are many other options.

Let me repeat the main point: Establish your rules early and stick to them.

Answer 6

If your objection to physics is that a consistent set of rules makes things boring, then any consistent set of rules will suffer from the same problem. But if it's just the fact that our specific rule set is just too boring (and I can think of a number of chemists who would argue against that point), then perhaps there's something more fun we can do for you.

As others have noted, how your fictional universe works is entirely up to you. You get to decide what works and what doesn't, and you don't ever have to explain why or exactly how everything works. As long as there aren't any glaring inconsistencies that can't be hand-waved away by being the result of a particularly powerful mage, and you don't give the readers any reason to complain at your ruleset, then you'll be fine.

In fact having a magical setting is already a pretty good start for slipping in some pretty outrageous things. The Will and the Word was pretty outrageous, but the Belgariad was one of the best-selling fantasy series. Tolkein apparently didn't even bother to figure out how magic worked in his world, but everyone lapped up LotR. At least the Elfstones almost made sense in the Shannara series.

Point being, don't worry about the why, just write the what.

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Now that's out of the way, let's look at the actual question...

Given that your universe works, you can leave pretty much all of the physical laws exactly the same as they are here. The two fundamental forces (yes, two: strong nuclear and electro-weak) are enough to account for basically all of the interactions except those having to do with space curvature (gravity). You just have to mix in a new force, field or other interaction effect that your magic can operate on to affect things.

Of course you don't even need to go that deep. What you want is some high-level rules that determine how things work at the engineering level. The average engineer doesn't care about the way that photons mediate the electro-weak force to produce chemical bonds, van-der-Waals force, normal force and so on. They care about the structural integrity of the materials and the way pressure is produced when you combust a propellant in a sealed chamber. You'd be hard pressed to find a bridge engineer who didn't know how to factor gravity into his designs, but few of them could derive the gravity equation from Einstein's field equations.

So don't worry about fundamental forces, particle interactions, whether or not there's a mediator particle for the thaumic field and what happens when you bash those particles together. Work up some engineering guidelines for how to actually use magic and let the Ponder Stibbonses of the world waste their lives on useless esoteric knowledge. Your average wizard is more interested in how to make flashy light shows or summon extra-dimensional entities to scrub their unmentionables anyway. (Which to be fair probably need scrubbing after their last summoning spell grabbed the wrong kind of extra-dimensional entity.)

Maybe start with figuring out how a squishy human brain can handle effects requiring megajoules of energy without the spill-over turning your skull into a pressure cooker. Using simple magic shouldn't have the sort of results we saw in Kingsman... although the pretty smoke clouds were a nice touch, I imagine exploding brains to be a little less aesthetic.

Answer 7

It is your universe and your rules.

As long as it is not self-contradictory, it can work.

Caveats:

1. If you have multiple small particles interacting, the whole thermodynamics (not only the energy conservation) will emerge by itself.

2. You can introduce whatever new particle interactions you want, but in most cases you will not actually need something much different from what we have here. We do have a lot of stuff, in fact. Just make some of it FDA approved.

3. Telekinesis is somewhat easy, but how exactly you pass thru the wall without sinking in the floor? Not being self-contradictory is HARD.