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Kyubey Fails Physics Forever



Today I finally finished all the Madoka episodes that have aired this season. I enjoy the series; it can get quite deep at times and the characters are well developed and likable. I'm not sure exactly how good this anime will be when it ends, but right now it's among my favorites. However, among other flaws, the latest episode finally revealed the motives behind Kyubey creating magical girls in the first place, and wow, it made me die a little inside. I wrote most of this out on a forum, but I'll add a little bit more detail and structure my thoughts more clearly.

Rant commence:

Kyubey fails physics forever. His explanation for creating magical girls out of humans is that the energy they create resolves the issue of entropy in the universe. However, Kyubey doesn't seem to understand entropy correctly. The concept of entropy does not state that energy is gradually lost over time, but that energy becomes less useful over time (a subtle but important distinction). He (well, technically IT but I'll use the masculine pronoun for convenience when referring to Kyubey) cites the second law of thermodynamics as the reason for this phenomenon (which he incorrectly interprets). Besides, what laws of thermodynamics are they following? They must obey the second law but completely ignore the first? Also, what's to say that the energy "created" by Puella Magi can be harnessed without increasing entropy as stated by the second law? Incubators must put equal work into the system in order to harness and store the free energy of witches, thus canceling any potential benefit. I guess one could argue that incubators have the capability to store free energy through their work (like charging a battery) but not create it, but that still does not explain how the energy is harnessed without the expenditure of energy. It's junk-science and it ticks me off that it's said in such a serious context, not to mention acts as the foundation of the antagonist's motivation. And another thing, entropy works on a scale of BILLIONS OF YEARS, and yet Kyubey acts like the universe is running out of energy like fossil fuels on Earth. And unless the power of human emotion has the power likened to that of several star systems (because the entropy caused by the dissipation of solar energy is what largely needs to be rectified right?), I doubt the energy harnessed would make a significant difference anyway. If it is on the level required to rectify the entropy of the universe, especially since the energy is meant to exist in "higher dimensions," the concentration of energy should rip apart the fabric of space time whenever a grief seed shows up, thus ending the world as we know it even before the Puella Magi get a chance to battle it.

tl;dr: If the writers mean "magic" they should just say "magic" without framing it into a crappy physics explanation.

I probably made some mistakes of my own in my physics analysis, so feel free to call me out on any errors I made. Still, there are obvious flaws in this motive that seem to contradict the very physical laws that rationalize the motive.


Only a couple of small adendums here. First is a shamelessly stolen tvTropes explanation.

  • 1) Kyubey's explanation to Madoka was an extremely simplified one. In fact, he even makes a few small mistakes, since energy and entropy are closely related, but not the same thing. It's quite possible that he/they know more about the universe than we do and he just tried to give an explanation that she would understand.
  • 2) From a narrative perspective, this is a Cosmic Horror Story. One of the key points is that the antagonists are not just evil, but too alien to comprehend. Madoka obviously didn't get one iota of his explanation and only cares that they are being sacrificed for something that would in no way, shape or form ever impact them. Remember, Kyubey is worrying about something that will happen along the lines of 10^50 years from now. This may be a big deal for them, but the human race wouldn't care less.
  • 3) Combining points 1) and 2), we have no clue just what exactly Kyubey is going for. Perhaps the collected energy is not subject to decay and can be stored to fuel one island of civilization inside a dead universe. Perhaps they are testing whether the energy can be farmed on a more controlled basis. Perhaps we're already on the brink of heat death and we just don't know it. All that matters for story purposes is that the reasons are outside of human comprehension. What makes Lovecraftian gods so scary is that they are not just evil (because something like Satan's evil, we can still comprehend), but we don't even know why they do what they are doing or whether they can even reason at all. The writers here are going for the same effect.

tl;dr: If you just throw science out the window and unlearn what you've learned, it's actually a pretty good explanation. However, if the writers wish to work within the bounds of science for some justifications and outside for others, that's not good. Bending science to your will is just a sign of not doing research and being lazy.

Also, there are two images from the new episode that I wish to talk about. This one suggests that it is not the power of the magical girl but the wish itself that causes the shift in entropy. I actually put this as a point towards pausibility, as it brings it further detached from the science it mangled so horribly. However, this one breaks my heart. We're talking about the ENTROPY OF THE UNIVERSE HERE! There's no freaking way that one person could contain that much energy without destroying the time space continuum. No way.

To conclude though, I'll quote what I said on an internet forum:

I don't care so much about Kyubey's crazy explanation. I don't care about the linearness and predictability of the earlier episodes. In the end, it really doesn't matter what Kyubey's motive is. It takes a side stage to Homura's motive; fighting what seems to be an impossible puzzle. While I do believe that the anime will have a downer ending, I wouldn't mind if she did find a way out. This is quickly becoming one of my favorite anime of all time. My favorite anime are not judged by their technical excellence, but their excellence as art, and Madoka epitomizes that standard.

Edit: 6/23/11

I might be a slowpoke here, but I just found out that the Know Your Meme page for Kyubey links this blog. I feel rather accomplished now.

Edit: 7/5/11

Response to ZetaAspect:

Firstly, I'd like to applaud you for finally calling me out. I was getting uncomfortable that my pseudo-physics analysis was not getting any opposition. In fact, as I stated, I did not want Kyubey to be wrong. In fact, I wanted to come up with some explanation, however implausible, that would make sense in the context of the anime (e.g. resolving endings like Clannad AS and Angel Beats, which are much messier than Madoka).

The reason I object to his explanation of the first law of thermodynamics is that it isn't just a simplification, but a justification for the main physics breaking principles in the anime. If one makes the assumption that energy can be "lost," then the fact that energy can be "created" out of emotion is not a far stretch. This, as you stated, probably should have been my focus, although looking back it is quite silly to point out "the power of love" as a violation of the laws of physics.

You make a very good point regarding the role of incubators. I had misunderstood how they function in the energy "creation" process. There would be no more work involved than that involving a rechargeable battery regaining power.

I was under the impression that humans were the only emotion capable beings in the Madoka universe, thus why Kyubey and the other incubators were on Earth. As for Madoka's energy potential and the implications of that, I suppose one can 1. assume that the time loop occurred MANY more times than was shown in the series (like with Endless Eight) and 2. that witches appearances WERE disturbances in the time space continuum, although not to the scale of tearing apart the universe (since in each "loop" Madoka's energy was not at dangerous levels).

Now, I love science fiction, but even then I call out times when the writers get science "wrong." You're right that writers have license to "invent" scientific principles (e.g. "subspace" in Star Trek or "emotional energy" in Madoka), however, I thoroughly enjoy it when these "inventions" work within the context of the laws of physics as we know them. Honestly, now that I'm reevaluating this problem, I don't think the writers even NEEDED to "change" the laws of physics that much, if they simply attributed more to "magic." Again, this was too high of an expectation from a series not targeted towards physics gurus (myself not included, obviously :P)

And of course, collection quotas can be within a certain "time" period (then again, what is time in this series?), and Kyubey's line did not imply that the problem was "solved," otherwise, he would have stopped collecting energy from the magical girls and found a way to release them.

Summary: He still fails, but less than I thought he had, and certainly less than he needed to.

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ZetaAspect avatar ZetaAspect
Jul 5, 2011

Wow, thanks for the response!

You might actually be right about humans being the only emotion-capable beings in the Madokaverse.  Kyubey implies that, but, then again, since when has Kyubey EVER told the WHOLE truth?  I personally suspect that there are emotion-capable beings elsewhere in the presumably vast Madokaverse, but it is very likely that they are not as effective for combating entropy (since Kyubey tends not to outright LIE, and he emphasizes their initial discovery of humans as a turning point).  I have nothing solid to base this on, though, so my argument for the immense scale of the anti-entropy operation is admittedly more speculation than I'd like.

Yeah, you're right about calling out sci-fi writers who go too far.  The trick to maintaining suspension of disbelief is to weave science and pseudoscience together subtly.  Puella Magi Madoka Magica fails at this because Kyubey infodumps most of it on us in episode 9, flirting with a genre-shift to hard-sci-fi.  At that point, it relies more on one's own pair of disbelief suspenders and on one's personal opinion of the show's status on the sliding scale of sci-fi hardness.  I always saw it as more of a surrealist work, so I was not expecting anything to make sense in any rational way.  Frankly, I'm surprised at and impressed with how solid the pseudoscience is, but it's still a sign of poor storytelling that it has generated as much skepticism as it has.

And when it comes to ultimate vindication of this anime's pseudoscience, we'd still have to deal with the ending/epilogue, and I'm just not sure how to handle that right now.

ZetaAspect avatar ZetaAspect
Jul 5, 2011

Now, granted, I haven't taken any courses addressing thermodynamics in a long time, but I really don't see the problems you do.  Maybe I'm just more forgiving of the physics in a series that features EXTRA-DIMENSIONAL MAGIC DUELS.  It's hard to say.

Anyways, firstly, I don't follow what the problem is in Kyubey's citation of the Second Law, other than colloquialization.  You are technically correct, and Kyubey is technically wrong; there is no loss of energy due to entropy.  However, I do not think it is too much of a stretch to talk about "energy usable for work" as "energy [in general]" to an adolescent girl with no physics background (not to mention the audience of Puella Magi Madoka Magica).  The problem of entropy is outlined rather well for the uninformed; energy will be unusable (and for all normal/non-scientific intents and purposes, it will be nonexistent) at some point in the distant future because it won't transfer spontaneously.

Secondly, you cite the First Law in a complaint about how Kyubey could store the energy without expending energy.  I don't really get the problem, since I could envision this harvesting process as more of a heat transfer from a high-heat object to a low-heat object, in which case external work would be unnecessary.  Granted, something as simple as this would result in horrifically low efficiency, but that may be irrelevent because the energy in question (emotional energy) is specifically stated to not be bound by the laws of thermodynamics.  This means that emotional energy lost in transfer will not necessarily increase physical entropy, allowing any harvested energy to just be used for combating/reversing entropic processes.

Thirdly, I think you mistake the scale of Kyubey's project.  He is one of many Incubators, and there might even be Incubators among other emotion-capable races on other worlds.  With the definite exception of Madoka herself, I don't think any magical girl has an amount of power capable of tearing the fabric of space and time.  Each girl is one of many from whom Kyubei collects energy, and Kyubey is one of many Incubators on a single planet, and each planet is one among many with emotion-capable occupants.  When it comes to Madoka, it involves time-loops and likely some sort of pseudo-paradox, the details of which I haven't quite worked out yet.  And, if you're still convinced that time-space should be getting torn a new hole practically all the time in this series, then I should remind you that there is at least a SENSE in which that happens, like, all the freakin' time.  Witches do that a lot, or at least they do something that can be interpreted as that, but with a lot less destruction, because the energy in question isn't subject to some of our laws of physics.

Fourthly, you claim that the writers are bending science to their will, and you practically state outright that this is bad.  I think many science-fiction authors might take offense at that accusation, since bending the rules of science is one of the staples of the genre.  Rather, positing one thing that defies what we know of science is normal, and does not display a lack of research and/or laziness, as you suggest.  FTL travel (without the use of wormholes) is one common device.  Another is time-travel.  Others are fuel-sources.  The list goes on.  In Puella Magi Madoka Magica, the wild-card is emotion, which doesn't play by the rules of thermodynamics, which has drawn the interest of a hyper-advanced race, causing all of the events of the series.  This seems fine to me.

Fifthly, you bring up two screenshots.  The first has the line "Your wish has improved the entropy."  I have seen this translated differently, as "Your wish has surpassed entropy."  Honestly, I'm not sure what to make of this.  The second has a line about a "collection quota."  I think it's reasonable for a cog (Kyubey) in the anti-entropy machine to have something of a monthly energy quota.  Fulfilling the quota doesn't mean solving the problem of entropy; it means not getting fired for professional negligence or for slacking off on the job.


If anything, you should be freaking out about how Kyubey's civilization can convert emotion to energy.  THIS MAKES NO SENSE, but we all seem to be cool with it.  Apparently, emotions are just like states of matter, and the change from hope to despair is wildly exothermic.  Not only that, but this reaction actually releases more energy than it requires to reach that state.  Wacky, but that's the fictional science of Puella Magi Madoka Magica, and I find myself willing to accept it at this point.

Ascrod avatar Ascrod
Apr 27, 2011

I'm so glad that someone else did a double take when he gave his grand plan for the whole Puella Magi scheme. Theey could have jsut said that their civilization runs off of osme kind of magic formed from the Puella-to-witch transformation instead of dragging bad physics into it.

highfyrebright avatar highfyrebright
Mar 27, 2011

We could always say Kyubey is a lying bastard.

greyweather avatar greyweather
Mar 7, 2011

Maybe if I pretend Kyubey never said any of that I'll still be able to enjoy this show.

This is like the opposite of what they did in To Aru Majutsu no Index, where the magicians gave the protaginist an explination, and then an episode later he went, "Hey wait, that doesn't make any damn sense."

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