[desrtsku]

^ sorry to say this but ... anti-matter or not, if we use the law of conservation, Kakine would only be able to create 1kg of Dark Matter with 1kg of fat ... and it didn't seem like he got thinner nor used any FMA tricks to transmute something around him >.> ... also let me remind you that electron has mass, considering Miko-chin's body resistance is 1ohm, she needs to move around 0.056856301kg of electrons per second to get a 1billion volt result ; not mentioning the potential difference her body should have to be able to do that, she'd pretty much alter the normal functioning of half of academy city's electronic devices just by sitting in the middle of the town (if we're going to the non-reality breaking theory then let's get serious ). And what about Aim Burst's mass? The ice blocs Aim burst created out of thin air?

My take of it is basically all the energy comes from the Personal Reality that AC espers give off. You basically replace reality with your own, and take affect the world that way. Hence, Kakine with his Dark Matter wings that appear out of 'nowhere' and AIM burst gaining a physical body despite being just made of energy (AIM field).

interesting *takes notes*, I think that theory can be taken as a solid argument to explain and defend the "non-conservation of energy" ... in a certain way. What's left is this I think :

Originally Posted by Chaos2Frozen

To put it simply, if Espers get their energy from nowhere, why does Mikoto get tired from overusing her powers.

Since I really can't picture a slender guys like Kakine or Miko-chin losing even more fat after using their powers (and since Flere's post gave me some inspiration), I 'll just try to pull a theory out of nowhere just praying it would make sense.

Someone already mentioned somewhere something about mental stress and then

Originally Posted by Chaos2Frozen

If she had mental stress, then where's the headache? Not to mention there was never any indication that her powers were calculation intensive.

Look at that scene and the one in the spar with Gunha, she wasn't exactly clutching her head now was she?

If we're talking about mental stress, headache is effectively a very recurrent sign ... but I'm not really going to argue on that since my point is a bit different.

Just a little introduction :
Our body regularly generates a small amount of adrenaline to stimulates certain parts of our organisms. But when we're under some situation of stress, that amount increases and obviously stimulate the entire organism generally resulting in the :
-dilatation of the air passages (allow the body to get more oxygen into the lungs quickly)
-contraction of the blood vessels, muscles and lungs
-fast increase of the heart rate
-huge consumption of the body's reserve of energy (especially recently absorbed glucose, but can even consume the protein reserve under special cases)
-...

Obviously such strains on the body can generate a lot of side effects. Generally :
-fatigue or exhaustion : since that process consumes a lot of energy
-feeling out of breath during some sudden but serious case
-nausea, vomiting and/or fainting during extreme cases of adrenaline outburst
-insomnia, muscles pain, backaches, headaches, etc ... especially/mostly in the long run
-Blood flooding from your nose when you overexert your brain, due to the rupture of certain thin capillaries in that region thank to the high blood pressure ... darn summer wars is such a good movie

Many factors can generate like many various mental strains like : being scared, performing annoying mental tasks, burst of anger, ... ; Or physical works ; Or some notable burden placed on any of the 5 senses (powerful light, loud noise, Mexican super chili sauce, pain etc) ...
Yes I'd even say you can feel exhausted, tired, out of breath and even faint just by seeing Samara coming out of your TV for real ... without doing yourself a huge physical task.
In Miko-chin's case, we have various cases of her being exhausted or out of breath after overusing her powers : most of the times she fought with Touma and another random "who's this guy/girl/woman?", Aim Burst, [COLOR="Purple"]and there's also the case when she tried not to overuse her power during the sister arc.

They're not that difficult to interpret :
1- That girl is a hotblooded tomboy and that's one of the many reasons why I fell in love with her, she's generally not the kind of person who defeats an opponent calmly ... no ... she shouts all the way, run all around the field like a crazy monkey, and even with her arsenal of electric attacks she doesn't mind punching her opponents directly if she felt like it. Of course, those statement are just to prove that she's the kind to have an easy burst of adrenaline, in addition to that her ability is the kind to generate noises and lights all over the place ... and it's humanly impossible to totally get used to that (if it was, then noises and lights wouldn't have been added in the major stress factor) ... so it's pretty normal is she gets tired after some serious encounters. Just to illustrate it even more even Touma just by stopping his lightning in vol 12, of course it wasn't because IB consumes energy but because he get the sh*t scared out of him.

2- that's pretty much the same when she fought against Aim Burst.
1 she was already pretty worn out
2 it's true that her power doesn't theoretically requires a huge level of calculation ... but even so, it'll get more difficult when you increase the value : X^2 might be easy or difficult depending of the value of X like from 10 to 0.97864billion volts (of course Accel's reflect is a special case since it uses the easiest to perform mathematical operation that ever existed) ... and like I said mental effort too provokes a huge release of adrenaline.
3 Headache : unless she tries to surpass her mental limits, I doubt she's get a migraine from using her powers (since it's not really on the same level of difficulty as Awaki's move point or Accel's control). But the possibility of getting exhausted after performing an easy mental task is still possible when it involves a lot of work (try to perform an addition with two numbers of 500 digits, I'm sure your head won't hurt but you'll surely fall asleep halfway) ... well, now we can say she indirectly burned a lot of glucose when she fire those enormous lightning bolts. The same goes with the adrenaline factor, it can provoke headache but not necessarily (if it was the case, all the guys in the X-game would have ice stuck on their head) ... though there are cases when it's unavoidable.

3-I think there's no need for any explanation for the sister arc.