I was thinking a bit about random things and came up with the following thought on a possible Magic-theory:

In Equestria, magic is used for everything. The energy also doesn't seem to be coming from the spellcaster, as Twilight clearly didn't eat all the calories needed to levitate an Ursa (Let's not even speak of Celestia and Luna...)

If energy conservation doesn't apply to magic, this would imply that the Equestrian universe overheats with time, as there is a constant energy input, but no output.

But what if magic was actually fuelled by cosmic background energy?

What I'm talking about is the idea of having an invisible magic energy field that matches the energy density of the normal universe.

A magic user could tap on the field and transform the magical energy into mundane energy to perform magic.

The resulting unbalance between magical and mundane energy would then lead to mundane energy flowing back to re-establish equal energy density.

This would mostly happen in the form of heat and background radiation, since they are the only forms of energy prominent through large parts of the cosmos.

By this, magic could actually counter entropy, as it gives a spellcaster a reservoir of concealed energy, which can be used to sort out the increasing chaos.

What are your thought's? I don't have a PHD and would like to know it this would actually be compatible with modern physics, provided we haven't discovered it and no-one in the universe draws too much magic.

4131298
It's the same result in either case. The universe freezes.

The heat death of the universe would actually happen faster if left mostly to its own devices since energy would be slowly taken from the system, and potentially converted into something else.

Plus things would act... weird, as particles and photons just upped and vanished to be eaten by the other dimension. Or particles randomly losing energy.

If sapient magical intervention is possible, then yes, they could keep society going forever by continually drawing everything they need from magic. The rest of the universe would freeze out, and areas around magic users would become localized pockets of comparatively extreme energy. Of course, eventually every spell you cast would take some of the matter or energy away from all the other existing matter or energy supporting civilization. Hopefully by then people will have learned population control.

4131298 This is an intriguing concept, and one which I have been batting around inside my cranial place for a while now. I am also a firm believer in the concept that everypony has their own wellspring of magical energy to draw from. Combining the two concepts into a developed Unified Field Theory of Magical Equivalence should prove to be an interesting and worthwhile challenge.

This would have to encompass Alicorn, Unicorn, Pegasi, Earthpony, Chaos, Changeling, and Dark magic, as well as the universal base magic field which permeates the universe/multiverse.

I feel that I shall have to get off my tablet, and log onto the computer so I may have the better platform for such a project.

4131349

It's the same result in either case. The universe freezes.

Actually the universe heats up, as the energy from the stars gets blown out into space, but I guess that's a matter of perspective.

There's also the question of much of the universe is actually controlled by sapient life. The Equestrian Sun is controlled and possibly fuelled by magic. And Luna at least claims to bring out the stars, so she could very well have a connection to them.

4131298
Well, due to the current nature of our universe, an expanding mass of extremely large amounts of energy, I would say that overheating is unlikely. The universe is expanding, but the amount of energy stays the same, so in many trillions of years, the universe's average temperature decreases (increasing volume compared to same amount of energy via conservation of energy.)

Entropy=chaos=Discord, so maybe he's got something to do with it? Another factor is the use of ice-like magic, like the Windigos, which decrease the temperature around them to feed themselves. And then we get the fact that emotions power magic, like love for changelings and friendship for Twilight.

This whole idea of yours seems to be based on the fact that conservation of energy is a thing in MLP, but it doesn't seem true. The Sun and Moon need to be manually moved, despite space having no friction, and thus inertia would fix things quickly. (Assuming there is nothing in space, but some sort of ether that could explain magic or something could work too.)

A possible solution to the whole:

A magic user could tap on the field and transform the magical energy into mundane energy to perform magic.
The resulting unbalance between magical and mundane energy would then lead to mundane energy flowing back to re-establish equal energy density.

This assumes that equilibrium for this stuff exists, and wherever magical energy comes from is a one-way trip. It is entirely possible that mundane energy is converted into magical energy and stored in wherever these creatures put it (like Windigos and absorbing thermal energy and hate as food).

This also assumes that ponies can tap into the cosmic background radiation (or energy, dark energy, dark matter, etc.) and convert it into mundane, which causes normal mundane energy to turn into cosmic background radiation. This means nothing's changed.

Magic (cosmic background energy) --> mundane energy. Mundane energy--> cosmic background radiation. Nothing changes. The only cool thing is that ponies can defy the Second Law of Thermodynamics, which probably does fall under "magic".

tl;dr Conservation of energy is still a thing in your scenario, and the expansion of the universe will prevent overheating anyways. Also, assuming magic follows the laws of physics creates a huge headache.

4131353
How would that wellspring be refilled?

4131366
From the human (or living, I guess) perspective.
Energy becoming diffuse to the point of uselessness.

In that case, then happy times. You have an eternal universe so long as everyone doesn't forget how to magic (totally a verb) and magic can be turned into matter.

4131370 not certain yet, but that is where the research is needed, so that the answers may be discovered.

4131298 I stick with conservation of energy. People tend to forget just how much energy is contained in matter. I gram contains 9x10^13 joules of energy, close to 1.5 times the strength of the bomb used on hiroshima; from 1 gram of matter. The problem is that everything is highly inefficient. The sun converts about 0.7% of its mass to energy. My theory is that unicorn magic directly (and relatively efficiently) converts matter to energy to use for spellcasting. With this energy density, a unicorn could easily eat enough food to sustain spell casting.

4131298
So when a spell consumed energy from this magical energy potential field, the mundane background energy (like the cosmic microwave background) would become more concentrated to compensate?

I think that would indeed be a counter to entropy, though I'd think a modest one (unless their universe is filled with a lot of magic users).

4131588
Hmm, Interesting theory. This could also explain, why we see so few toilets in the show

It would be interesting to estimate, how much lighter the planet becomes each year that way.

4132320
The spell creates mundane energy (in the form of heat, movement, light or matter, depending on the spell), by pulling on the magic energy field.

The magic energy field reclaims the missing energy by sapping upon cosmic background radiation and heat.

4133227

This could also explain, why we see so few toilets in the show

Or toilets aren't really an important part of the show and that's why they're not really shown.

It would be interesting to calculate that, obviously it wouldn't change that much. I don't think it would be an issue.