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I’ve been a bit slow in responding to the new math drama Suugaku♥Joshi Gakuen starring a whole bunch of H!P members, but now that the first episode is out, here’s a post.

H!P math drama??!!! I’ve been waiting for this my whole life! (Never mind that my life predates H!P.) And of course I’m happy to see Sayu starring as a math geek, given the interest she’s expressed in the subject.

I don’t have time right now to do a full review of the first episode, but I’ve found it quite awesome so far, with respect to the geekiness, though the number of typos I’ve spotted have been quite a distraction. The series has apparently been developed in cooperation with the Mathematical Olympiad Foundation of Japan, so the math is essentially correct, as far as I can tell so far (I haven’t dissected most of it yet), though the editing work seems to have been rather sloppy.

Also, I’m not sure who’s planning to fansub this drama, but I would like to volunteer as a math consultant. So if you are working on this, please sign me up. I think the kinds of mistakes that have slipped through the editing can also pop up in translation, and I can help look over the translations and correct any possible math errors.

Here are some typos (and non-typos) I’ve found:

The first equation is given as \lim_{x\to a} f(x)=a. This says that the limit of f(x) as x approaches a is equal to a. As written, this is only correct for all values of a if f is the identity function. This should probably be \lim_{x\to a} f(x)=f(a), which is true for all continuous functions.

The second equation says \frac{d}{dx} = a^x = a^x \log(a). There is an extra equal sign here. It should be \frac{d}{dx} a^x = a^x \log(a). This is the derivative of ax respect to x.

The third equation is fine as is, and expresses linearity of integration.

This clock is just awesome. It has expressions evaluating to or otherwise indicating each of the integers from 1 to 12, which we would see on a normal clock.

  1. \tan(45^{\circ}) — the tangent of 45°, equal to 1.
  2. \sum_{i=0}^{\infty} 1/2 — this is a typo; should be \sum_{i=0}^{\infty} 1/2^i, an infinite series converging to 2.
  3. &#x33i — this is another typo; should be 3, an HTML code for the character 3.
  4. 2^{-1}\mbox{ }(\mbox{mod }7) — the modular multiplicative inverse of 2 (mod 7); 4 and 2 multiply to 8, which is congruent to 1 (mod 7), so 4 is an inverse of 2 (though not the only inverse; 11 is the other integer on the clock that satisfies this property, which makes this a flawed clock).
  5. X^2=3^2+4^2 — solve for X, which can be either 5 or -5.
  6. 3! — the factorial of 3, which is 6.
  7. 6.\overline{9} — this repeating decimal is equal to 7.
  8. \sqrt{64} — the square root of 64 is 8.
  9. 3(\pi -.14) — since π is irrational, this is actually 9.004777960769…, but it’s approximately 9.
  10. -8 = 2-X — solve for X, which is 10.
  11. 0x0Bhexadecimal for 11, with the standard hexadecimal prefix of “0x” used in Unix-like shells and C.
  12. \sqrt[3]{1728} — the cube root of 1728 is 12.

This is given as v = \sqrt{2}gh, but the radical should extend over the entire right-hand side: v = \sqrt{2gh}.

In context, Nina (Reina’s character) swings on a rope into the classroom. This expresses her velocity at the lowest point of her trajectory.

Nina starts out with a gravitational potential energy of mgh (m is mass, g is gravitational acceleration, and h is height, measured relative to the lowest point of her trajectory) and no kinetic energy prior to swinging on the rope. At the lowest point, she has a kinetic energy of \frac{1}{2} mv^2 (m is mass and v is velocity) and no potential energy. Due to conservation of energy, these two are equal:

\frac{1}{2}mv^2 = mgh
\frac{1}{2}v^2 = gh
v^2 = 2gh
v = \sqrt{2gh}

It seems Tsunku♂ has joined the eminent ranks of Napier, Fermat, Gauss, Cauchy, Lagrange, et al…. :o

The release of the new Hello! Project group album Champloo 1 ~Happy Marriage Song Cover Shuu~ includes new tracks by a number of revived H!P groups, most of them with extra bits appended to their names. Due to the name changes, I’m inclined to consider them new groups rather than new generations of old groups—with the exception of Aa!, which retains the same name but has had Tanaka replaced (‽). At the same time, they each have only one album track to their credit, so I would categorize them among other fledgling H!P groups like Shigepink, Kohappink (btw, happy birthday to the both of you! XDDD) and POCKY GIRLS. Most of these fledgling groups have been overlooked by many fans, though fortunately many of them do have their own Japanese Wikipedia pages. These fledgling groups deserve another post, which is in the works…

But this post is about ZYX-α, the only revived group that has undergone a change in number: while the original ZYX had six members, the new ZYX-α has eight, retaining only two of the original members (Tsugunaga and Umeda). I’ve always thought the name “ZYX” was supposed to be a pun on the number six, so it is interesting that ZYX-α would be the group to change number. So does “ZYX-α” somehow indicate eight?

Indeed it does! In physics, α (the Greek letter alpha) is commonly used to denote an alpha particle, which is two protons and two neutrons in a bound state (or a helium nucleus). The name comes from Ernest Rutherford’s classification of radiation into alpha, beta, and gamma types, named after the first three letters of the Greek alphabet. Alpha radiation is the least penetrative of ordinary matter, while beta radiation (electrons) and gamma radiation (photons) are more so.

So “ZYX-α” can be interpreted as indicating ZYX with an alpha particle attached. Given the physics context, we can take “ZYX” to be an abbreviated form of “atomic number six”, since Z is a conventional designation for atomic number, the number of protons in a nucleus. This refers to carbon, the element with atomic number six.

The name “ZYX-α”, then, would refer to a process in which a carbon atom and an alpha particle combine. In other words, this is the alpha process, a nuclear fusion reaction that takes place during stellar nucleosynthesis, in which stars build heavier elements out of lighter ones. The formation of carbon out of alpha particles is known as the triple-alpha process, and once carbon is formed, heavier elements can be produced by additional alpha processes.

In the diagram below, the “ZYX-α” reaction is shown on the right, following a triple-alpha process:

Triple alpha process, ZYX-α

So the “ZYX-α” reaction produces an oxygen nucleus with atomic number eight.


They look just like an oxygen nucleus, don’t they? ^_^


No, I’m afraid the similarly abbreviated quantum electrodynamics has yet to make an appearance on this show. But this episode does touch on static electricity, and since it glosses over the details, I’ll try to elucidate them here.

As explained in the episode, this creepy doll is responsible for death of the unsavory character lying lifeless at its feet.

This feat is accomplished when the dolls’ eyes (intentionally designed by museum’s curator for this lethal purpose) collected enough static electricity to deliver a jolting shock to the character, interfering with his pacemaker and giving him a heart attack.

Oh, the agony … and the super-cheap special effects.

OK, I’m not going to comment on how practically feasible this whole gimmick is. The concept is flaky, the explanation is sloppy, and the acting seems a bit inconsistent with the explanation, but I’ll try to explain what I think is going on anyway—on a theoretical level.

As an explanation, MIT genius kid Touma Sou says the eyes are Leyden jars, which the show tries to spectacularize by displaying a faux-historical shot of a manuscript page depicting the eye as a Leyden jar, surrounded by informative-looking scientific text …

… until you realize what it actually says:

[…] Christ in Garmany has discoveed static to be
[…] to be accumulated with such apperatus the there
[…] qgo though it is assuumed that it was a wire
[…] straightens statice electricicity, and it was devised
[…] petel van Musschenbrooke peter van Masschenbroek
[…] the Nethelands in 1746. There is a name of
[…] Leyden jar” becaus of haping þeen inovented
[…] the Leydun university in the Netherlands.
[…] was widely used for experimental use of
[…]lectricity, and it was used to experiment
[…] B. Franklin‘s kite deep-frying.


Is a generic name of the
material that doesn’t pass electy
or heat easily. It is said to
conductor (electric condactor) that
conducts electricity easily the noncond
(..referrig…singing). Moreover, the
insulator shows the dielectric substance.

The electric resistance of silver

Ag of the atomic symbol originates
in name “argentum” in Latin. Both of
the reflectivity of the electric condutivity
and the visible light ray are
the maximum in the metal
it was called “silvery white”
from the thing with
high reflectivity of
light in Japanese.


No- quality solid where
glass transition phenomenon is

LOL at the “Christ in Garmany”? And I’m not really sure what Ben Franklin’s culinary prowess with respect to the deep frying of kites has to do with anything, so let’s move on.

Here’s the diagram again, with the three labeled surfaces explicitly marked A, B, and C. I’ve also labeled a screenshot of one of the eyes. Note that the diagram labels the “Insulator” and the “Glass” separately, apparently confusing the generic concept of an insulator with an actual insulating material. In this case, the two surfaces are the same thing, and I’ve labeled both of them C. A is the exterior conducting surface, apparently made of silver, and B is the interior conducting surface.

As the show explains, people walking with rubber-soled shoes across the wool carpet pick up negative charge due to the triboelectric effect. In appropriate conditions (cold, dry air), there’s no conducting path for this excess charge to dissipate from the body, so it remains. For someone with negative charge to experience an electric shock, the negatively-charged electrons on their body have to travel to a region of more positive charge. The electric potential between the two regions is greatest when the respective charges are furthest apart, so the best conditions for such a shock would arise when someone is touching a positively-charged surface.

My best guess for how this positive charge gets there is that it is induced by rubbing the (silk?) cleaning cloth against the porcelain surface of the doll’s face. Since silk is higher up on the triboelectric series than unglazed porcelain, a positive charge collects on the cloth. If the cloth then comes in contact with the pupil of the eyeball, its positive charge is transferred to the interior, as both pupil and interior comprise conducting surface B, and the close proximity of conducting surfaces B and A induces a negative charge on A. This works if A is properly grounded, which I’ll assume is the case.

The attraction between A and B allows B to collect a large amount of positive charge, enough to result in a big spark, though this is limited by the capacitance of the eyeball, which is probably not that high due to the apparently limited surface area of the two conducting sheets.

So when negatively charged unsavory character touches positively charged pupil, electrons discharge and enter the eyeball, causing said unsavory character to experience a huge shock, flail dramatically, topple to the ground, and expire. C’est la vie.

That’s my take on it. The show’s explanation, as far as I can tell, mentions negative charge on both bodies without discussing positive charge at all, which is necessary for the discharge to occur. In addition, Sou’s rubbing of the doll with a cloth clearly misses the pupil, which leaves the viewer wondering how that could have effectively transferred any positive charge into the eyeball at all.

I’m afraid that on a technical level, this episode leaves me much more disappointed than Episode 1, unless I totally missed what’s going on (and please enlighten me if that’s the case!). Oh, well. Let’s hope there’s more awesomeness to come….

EDIT: Did you think I was going to let you go without some physics equations? Of course not!

Let’s figure out how much energy is transferred when someone gets a shock from touching the doll’s eyeball. Since we’re not given all the information, let’s make educated guesses. Suppose the outer conducting shell has a radius of 2.5 cm, and it’s separated from the inner conducting shell by an insulating layer of 1 mm thickness. The diagram says it’s made of glass, so let’s give it a dielectric constant of 5. Furthermore, we’ll idealize the whole thing as a spherical capacitor, so as not to worry about those bothersome non-symmetric electric fields.

We can now compute the capacitance of the eyeball, replacing the glass with vacuum temporarily. If there is a charge of Q on the inner shell, the electric field at radius r outside between the two shells is

E = \frac{Q}{4\pi\varepsilon r}.

Integrating this over r between the two shells, we can compute the electric potential difference between them:

V = \int_{r_1}^{r_2}  \frac{Q}{4\pi\varepsilon r} dr =  \frac{Q}{4\pi\varepsilon} \int_{r_1}^{r_2} (1/r) dr = \frac{Q}{4\pi\varepsilon}\left[\frac{1}{r_1}-\frac{1}{r_2}\right]

Since capacitance is charge divided by voltage, the capacitance is

C = \frac{Q}{V} = \frac{4\pi\varepsilon}{\left[\frac{1}{r_1}-\frac{1}{r_2}\right]}

The energy of a discharge depends on the charge Q transferred:

U = \frac{Q^2}{2C} =  \frac{Q^2\left[\frac{1}{r_1}-\frac{1}{r_2}\right]}{8\pi\varepsilon}

Assume a typical charge of 1 microcoulomb is transferred. Then, plugging in our assumed values (r1 = 2.4 cm, r2 = 2.5 cm, Q = 1e-6 J, ε = 5ε0), we have about 0.001498 joules, which is the amount of energy needed to move a one-kilogram block a height of 0.1527 millimeters.

Countdown! The Top 100 Hello! Project PVs


At this rate, we’ll get to the #1 video in the year 2023 or so…

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It’s no longer Koha’s b-day in my time zone, but it’s still Koha-day in most time zones west of here, so …


Seriously, the double dactyl is the most demented form of poetry ever … hence, perfect for Koha. ^_^

(see Part 1)


Futari wa NS

Futari hitori,
Hikaru, Kirari
Team up to try to dis-
Prove Gauss’s rule.

Finding no monopole,
Sadly they figure that
Poles must be dual.



World-weary Koha-chan
Cuts ‘cross Kamchatka to
Kolkata … more!

Finished with traveling,
Koha now looks for a
Place to explore.


Sansan GOGO

Misinformed MilkyWay
Err in directing us
Which way to go.

5-prime to 3-prime‘s how
Nucleotides link up
All in a row.



Olala olala,
Mademoiselle Kusumi
A commencé à chan-
Ter en français.

Cependant, tout le monde
Trouvait son accès de
« Francocacophonie »
Vraiment mauvais.


* A rough English translation that loses all of the delicious rhyming tonguetwistery of the French:

Olala olala,
Miss Kusumi
Started to sing
In French.

However, all the world
Found her outburst of
Truly bad.



Yayz! I wanted to do 16 double dactyls in honor of Koha’s turning 16, but since double dactyls do double duty, so to speak, 8 should be enough. ^.^

I’ll probably have more double dactyls to post in the near future, though….

Happy birthday Koharu!

In celebration of Koha’s birthday (07.15), here are a few double dactyls I’ve composed:



Pancakey pancakey,
Master chef Kirari
Proves she can pancake-sort
Faster than SHIPS.

Quite inexplicably,
This method takes but a
Number of flips.



Flavor Flav, baklava,
Koha-chan’s talk of a
Genuine flavor” is
Just a disguise—

Hard-to-find particle
Actually is quantum
Largest in size.


Hana wo Pu~n

Kirari pikari,
Koha and Mai, though
Experts at tangent and
Cosine and sine

Find themselves thwarted by
Transforms affine.


Konnichi pa

Konnichi pa-pa-pa!
Kirari’s tra-la-la
Seizes the heartstrings and
Moves one to tears.

Poignantly touched by her
Passersby nonetheless
Cover their ears.



More double dactyls are in the works, so stay tuned!

(see Part 2)

I. Tsunku: The Enigma

If one follows the development and output of Hello! Project, one is likely well acquainted with Tsunku, the Producer:

Of course, Tsunku does not produce everything in Hello! Project, nor is his work limited only to production. A prolific lyricist and composer, he is also responsible for writing most of Hello! Project’s songs. One need only scan any recent (Tsunku-produced) Hello! Project release to see Tsunku’s name emblazoned across the front cover, acknowledging his role in producing the record. In addition, on the interior of the liner notes, one may often see both the lyrics and composition of the tracks attributed to Tsunku, his name rising elegantly above the very words he has penned.

Indeed, let us journey together, dear reader, through the experience of gazing upon Tsunku’s name as it appears on the Berryz Koubou single “VERY BEAUTY”, selected arbitrarily as a typical example of a Tsunku production.

Observe in particular how the three simple hiragana strokes (つんく) are embellished with a Mars symbol (♂), prominently displayed yet not intended to be pronounced. An interesting touch, otherwise attributable to Tsunku’s idiosyncratic whims but for the fact that this name appears differently on the interior:

Here the Mars symbol is noticeably absent. One might dismiss this as a mere typographical error, but closer examination of other recent Tsunku productions reveals that the Mars symbol is consistently missing from the lyrics and composition credits while present on the cover production credits.

One might fancy the notion that behind the “Tsunku” nom de plume lies a team of two individuals, one a producer and the other a lyricist and composer, differentiated only by the presence or absence of the Mars symbol. While there is some merit to this possibility, one must consider the history of this peculiar symbol as it is displayed on the covers of Tsunku-produced releases over the ages. In particular, one must note that early Hello! Project releases credit Tsunku as producer without the Mars symbol.

Immediately some pertinent questions arise: At which point did Tsunku the producer begin adopting the Mars symbol as an essential feature of his pseudonym? Did he consistently omit the symbol prior to this point, and has he consistently included it since then? And perhaps most importantly, why are there two Tsunkus now when once there was but one?

Speculation about Tsunku’s gender identity and/or sexual orientation aside (to be addressed in due time), let us examine in detail, dear reader, the evolution of this name, in hopes that such an endeavour may uncover heretofore unacknowledged clues to illuminate this enigmatic figure and to guide us in dissecting this mystery.

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Countdown! The Top 100 Hello! Project PVs


After a three-month hiatus, the Countdown continues! And you thought I’d abandoned it!

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Countdown! The Top 100 Hello! Project PVs


Welcome to yet another installment of Kawaiirrhea Goes on a Rampage and Invokes Left and Right the Names of Topic After Topic That Should Never Be Mentioned in Connection with Hello! Project.

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Countdown! The Top 100 Hello! Project PVs



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Countdown! The Top 100 Hello! Project PVs


My last post has apparently sparked a “laugh riot” of a debate that’s now more than three times as long as my original post. If you haven’t seen it yet, you may find it worth reading. Or maybe not.

As always, I appreciate your feedback, positive or negative. It’s always good to know how effective my communication is.

And now, on to the next batch:

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Countdown! The Top 100 Hello! Project PVs


The next 5 PVs:

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Sorry I haven’t posted in a while. Since classes actually started this week (yesterday), I’ve had less time to devote to blogging, so I’ll probably post less frequently. Unless I feel like sacrificing my grades to the Altar of Tsunku … which is mighty tempting. I’m actually skipping a class right now to write this. Terrible, I know. But this is more interesting.

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Countdown! The Top 100 Hello! Project PVs


It has begun! :-) (see previous post for details)

But before it actually begins, I’m going to hand out some honorable mentions. In fact I’m going to hand out 20 honorable mentions. This is actually a shameless, thinly veiled excuse to produce a Top 120 countdown without bothering to rank or discuss the bottom 20. But still … these were the noteworthy videos that almost made the cut. And there were some pretty difficult decisions to make, so I feel they all deserve a mention.

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DJ Kirarin☆Snow ☃'s remixes are now appearing at K!☆Mixed.
November 2020


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