Physics from a Non-Brony: The Sonic Rainboom unraveled

What you're doing is basically admitting that "MLP isn't consistent at all, so one shouldn't consider any of the feats to be quantifiable using real physics".

(EDIT: Okay, you changed your message ColdMouse, now nobody will understand what I'm replying to!)

...Which I completely agree with. That's actually been the point of this entire thread. I disproved the claim of "Rainbow Dash is Mach 5+" by exposing the fact that the entire scene is filled with inconsistent or contradictory information, and thus such a conclusion is pointless. The fact that the only reliable speed calculation I could manage to get was 108 m/s (which didn't have anything to do with advanced aerodynamics and was just simple logical analysis) is actually inconsequential, since the entire post was mostly about how difficult it was to actually locate a part of the scene that was consistent enough to measure accurately!

 

But Superman doesn't have infinite speed at all. That's the Flash you're thinking of. All the versions of Supes' have an upper limit to their abilities (although not exactly know, they could definitely be outrun/out-muscled/etc. by certain others regardless of willpower).

...Even the Mary Sue one, Superboy Prime.

Assuming unlimited potential for Rainbow Dash sounds awfully a lot like a form of the proof by example fallacy known as the "No-Limits fallacy". So I think it is wrong not because it uses Earth physics, but because it assumes that because she hasn't shown one, she doesn't have an upper limit to speed.

 

I do believe the "proper" trope name for that would be "A Wizard Did it"?

 

This. This is EXACTLY a "No-Limits Fallacy". Unlimited potential isn't directly unlimited ability, but it's the infinite capacity to increase in ability. One doesn't logically assume that, because something shows no limits, it doesn't have one; one logically assumes that it has a currently unknown limit, unless it exhaustively shows that it has no limits in any known setting (which still doesn't mean it's got unlimited potential, just that we can't find a limit). And that isn't the case here, since Dash has only made a Sonic Rainboom some 2-4 times in the entire series as far as I'm aware, which is hardly exhaustive at all.

...Except for the fact that it has been used as an escape trope in this thread. Even you have been using it:

A Wizard Did it: where any discrepancy in consistency, impossible event, and/or continuity error of a series is explained with a simple explanation of "it was magic" and is excused from further scrutiny.

Both your comment and the definition of "A Wizard Did it" sound pretty much equivalent to me, dude...

I'd already conceded, in the original post, that I believed Rainbow Dash was intended to be considered transonic in canon due to evidence such as the name of the phenomenon itself (sonic rainboom), and that I'd respect that intention in this case because I had deemed actually calculating the speed of Rainbow Dash to be a futility thanks to the general inconsistency of the physics in the show. But, since you're giving me a list of things I have to consider, I'll address them out of respect.

• First of all, "breaking the sound barrier" in this case wasn't actually explicitly mentioned in the show, was it? There was a visual "rainboom", but like the "Mach cone" this is a visual effect that doesn't exactly follow physical laws and thus can't be considered completely reliable. That having been said, I still consider her to be transonic because of the rainboom, simply because I understand that the intent of the creators was to show that Dash was moving faster than sound.

• "Once a variable is declared, you would have to delete or "undeclare" it before it didn't work anymore." I'm not even sure what you're talking about here. Can you clarify?

• Pinkie's "luck" as well as "magic" and "Alicorn power" (which is still magic, isn't it?) are completely unquantifiable variables in this setting, since they have no defined limits and can thus be used to explain anything that doesn't make sense (A Wizard Did It).

• I'm not excluding these variables because I don't like them, necessarily. I'm excluding them because they literally don't add anything remotely useful to the logical analysis other than the conclusion "A Wizard Did It".

Also, I don't mean to be picking on you. But you're saying a lot of things that are contradictory, so I can't help myself. I'm really not trying to make you look stupid or anything like that. That's not my intention at all.

 

I respectfully disagree. It is not a "variable".

A variable is the operationalized way in which an attribute is represented for further data processing, and have domains, which are the set of all possible values that the variable is allowed to have. Operationalization is the process of defining a fuzzy concept so as to make the concept clearly distinguishable or measurable and to understand it in terms of empirical observations.

Magic does not have defined domains, and is definitely not operationalized. In the show it's a pretty fuzzy concept that is used to save the day in many of the episodes by providing the necessary Applied Phlebotinum for the problem at hand; like solving Discord's mind-break effect in under two minutes.

Because things like "magic" and "luck" in this context are clearly undefinable and unquantifiable, they can't play a productive role in actual calculations, so I won't consider them in any possible "future algorithms" that may happen, if any at all. That having been said, I wouldn't consider completely disregarding them as a whole in the logic process, but I always consider them last, since such things are generally unproductive attributes when trying to quantify feats.

Do you understand what I mean now?

 

I believe the statement "bees shouldn't be able to fly" is attributable to some of the earliest investigations into aerodynamics, notably the derivation of the lift equation, which is an empirical formula based on observation of aerofoil sections in wind tunnels. According to the lift equation, Bees supposedly can't fly because the wing area, lift coefficient and weight of the bee don't fit the equation. All this says is that the equation is inadequate for bee flight, since bees obviously can fly. As far as I recall, the mystery was only really solved somewhat recently, within the last 20 years. New research indicates that insect flight takes advantage of a variety of dynamic effects such as the formation of vortices by the rapid wing vibration which cancel much of the induced drag. In addition, insect flight needs to be analyzed at much lower Reynolds numbers than aircraft flight, since for the insect, the viscosity of the air is much greater relative to its size.

...That's the best I can do right now. Sorry.

I'd have to disagree. I really don't think she'd be capable of doing significant damage to him. Her best destructive feat is building busting (able to completely destroy an average house in one attack upwards to communal buildings with greater than 5 floors), which is equal to 380+ up to nearly 600 kg of TNT. Starscream has town-level (able to withstand something that would devastate at least 1.4 square kilometers up towards 78.5 square kilometers) showings in durability, which would be equal to 5.8+ to nearly 405 kilotons of TNT. Even with the possibility of manipulating lightning, she doesn't seem to have very powerful attacks (the lightning she creates doesn't seem to be anywhere nearly as powerful as real lightning). I honestly think that she'd quickly find herself out of options and on the defensive.

...But I will agree that she's smarter than him. That would probably be her one saving grace. Unfortunately, she can be rather prideful and stubborn as far as I can tell, so that might counteract her only advantage long enough for Starscream to do her six feet under.

 

Actually, it's closer to 1996:

Here is a section that talks about the aerodynamics of insect flight in detail. It's rather complicated stuff, so I wouldn't be surprised if you looked at it and said "wut". What I can tell you, though, from my having read it is that Rainbow Dash is flying quite impossibly.

Using Physics-Brony's estimate for a pony's mass (275 kg), that makes Rainbow Dash 91,666+ times more massive than the largest flying insects, which would mean she would still need to have vastly larger wings, and her Reynolds number would be massive as well. With her current wings, she would have to flap 1000+ times per second. In short: impossible flight is impossible.

Then again... MAGIC PONIES ARE MAGIC.