The Layman's Physics Discussion

[Mysterysword]

So let's talk about physics, and the magicks we see that allow people to circumvent its laws. Not to mention, the effects it should have on a person's body.

One big question I had throughout HW (and also looking at the designs of airships) is if atmospheric pressure actually exists on Hydaelyn. By all accounts, it should - Hydaelyn is a spherical planet with lifeforms extremely similar to Earth, and follows the basic laws of gravity. That means that the various layers of the atmosphere should also be present. With that in mind, shouldn't the air in Azys Lla, Sea of Clouds, and Churning Mists all be substantially thinner than what we're used to? Forget about us, do Estinien, Ysayle, and Alphinaud not experience any negative effects of this? Alphinaud even mentions that it's actually really cold in the Mists.

But moving on from atmospheric pressure, let's go under the sea. Pressure exists there too. The deeper you dive, the more water is pressing down on you (because there's more water above you). Due to ignorance of the finer details of the effects this has on the human body, I can't go into detail. All I really know is that decompression sickness can very easily kill you, and that when you're deep underwater, it's very easy to get disorientated, especially when there's no light and you cannot easily tell what's up or down.

What I do understand, however, is the fact that after receiving the Kojin's blessing, Alisaie and Lyse suffer none of these ill effects. They're able to go deep-sea diving and, presumably, swim against currents which should be very strong under the Ruby Sea. They can talk in water, and more importantly, they can breathe water. Which sounds like a major biological change in a mammalian species, caused by a magical ritual. A magical ritual that apparently has the power to change a person's body without them suffering any negative side effects from the change. Primals, anyone?

And just for the record, I do understand how and why these issues were glossed over in-game: for the sake of convenient storytelling. But I just want to theorise about how things like these could possibly work, on a lore level.

[Lambdafish]

Like a lot of Japanese media, huge liberties are taken with this kind of thing and a sense of suspension of disbelief is needed.

If you want an actual answer though, Yoshi P says "magic" I guess

[TinyRedLeaf]

Fat chocobo flies. Adamantoise shoots fire and spins. The flying cloud remains a cloud, underwater.

I'm pretty sure we're not in Kansas any more.

[Aosha]

Now that you mention atmospheric pressure, deep sea pressure and decompression sickness...
Imagine TELEPORTING (i.e. moving instantly) from the bottom of the Ruby Sea to Moghome.
I'm kinda glad we don't have to deal with that. @_@

[Alien_Gamer]

If several million tonnes of rock can be suspended indefinitely in midair from an overabundance of air aether why is it difficult to believe that would also supply an abundance of air to breathe?

Breathing underwater can be explained in much the same way. The aether from the ritual is converting the water to air or stripping the hydrogen from it leaving it safe to breathe. Our natural carbon dioxide exhalations wouldn't dissipate immediately in the bubble so we don't need to worry about oxygen poisoning from breathing too pure of an oxygen. If the above is possible then mitigating the pressure exerted by expanding bubbles of gases trapped in our body would be a relatively minor thing to include as part of the ritual. We're repeatedly shown that aetheryte crystals have the ability to create/warp/manipulate energy and elements throughout the game so this is by no means a stretch of the imagination.

TLDR, magic.

[Sylvain]

As a physic student I cannot say I did not notice all these details. While I try my best to think of a scenario where all these things could make some sense, there are obvious loophole. Considering the size of some structure and the ability to fly of most things which don't seem the most adequate physiology to do so (flying swiiminglike snake from Vanuvanu), what could make some sense is that hydealyn first is a less massive planet resulting in a weaker g force. My guess would be that 80% wouldn't make much of a difference wheen it comes to running or ground battle, but it would allow much taller structure to exist like ishgard. A much thicker atmosphere could also help explain how some animals manage to fly. Lower gravity + denser makes flying akin swimming in a liquid with extremely low viscosity.
A much Thicker atmospher could also help resolve your question regarding pressure underwater.

[Sylvain]

However, hydealyn being a magical world, the unknown properties of ether must always be taken into consideration as it seems to be an integral part of the world to its very core. In short, we can\\\\\\\\\\'t explain ff14 physic without understanding ether, and unfortunately no one does. (and I doubt SE has hired any physicist to make some pseudo science out of thin air to make a magical world more believable)

So, as Y. P would say, "it\\\\\\\\\\'s Magic"

[YianKutku]

I forgot where I first heard it or the exact wording, but I recall a saying about SF&F storytelling about how the softer the science, the harder it is to get away with suspension of disbelief. Hence the myriad threads we have about morality and philosophy of in-game characters.

I suspect there is also a corollary to the saying, which is the harder the science, the softer we are on suspension of disbelief. So the vast majority of weird stuff in the game setting is handwaved away with "magic", or specifically "aether". For example, the critters that can fly without wings are said to do so by directly manipulating the wind aether around them. How exactly this works can probably be vaguely dismissed until someone else works it out (by forcing interpretations and coming up with explanations on the fly), at which point the lore pretty much goes "eh, good enough".

Having said that, I could have sworn there's a sidequest or Job quest with a NPC from one of the three starter city-states who has to go up Sohm Al to the Churning Mists, and complains of shortness of breath due to the high altitude. I can't remember where it is, though, or if I imagined the entire thing.

We even have canonical examples of people from Othard coming to Eorzea and getting aether sickness from the sheer amount of aether around, so there's precedent for acclimatization issues.

[sciencebot]

Hydaelyn is a spherical planet

As long as we're asking the tough questions: Can you prove this premise you're working off?

If you stand in Kugane and a friend stands in Ul'dah, and you share the positions of your shadows by linkshell at exactly the same time, they'll be the same, despite having a full continent between you in either direction. No matter where you are in the world, the sun is in the same place relative to your position, the clocks are the same, all of it. That shouldn't be the case on a spinning ball-shaped Hydaelyn.

And have you ever seen anything disappear over the horizon? I haven't. There's usually a mountain or a zone border long before you could, to disguise the mind-blowing truth: FLAT HYDAELYN.

the ascian moon cutscene was shot on a garlean soundstage

[PArcher]

I've tried to explain magic with science in some of my settings, and while I can get some things to work, there's a lot that just completely conflicts with known sciences so much you have no choice but to say "its magic!".

For example, how can you explain polymorphing/shapechanging spells/abilities with science? (or at least in such a way that allows complete reversal with no physical harm to the object) Like our much-loved Toad spell in PoTD...