Original Poster: Frostybox (http://pastebin.com/u/frostybox)
Reason this is posted here is because it's not binned in Frosty's bin.

>“Sis SIS!”
“HA!”
>With one solid swing of your rearlegs the apples drop perfectly into the bucket leaving one completely clean tr-
>There’s one apple left up there.
“Now I don’t want to see your tammyfoolery there apple, y’all know how this works. Now go on, get!”
>You nudge the tree with a forehoof and the apple drops on top of the pile.
>Nothing like some honest work for an honest m-
>”SIIIIIIIS!”
>You turn to your little sister racing up to meet you.
“Now hold your cattle there Applebloom, what’s got y’all so riled up this time of day?”
>”Sis! It’s the most amazin’ thing I done ever seen! Y’all gotta see what Anon’s done!”
>You can’t stop the frown forming on your face.
>Applebloom notices your displeasure, but refuses to back down, “I know what y’all are thinkin’ but if y’all would just listen to him this one time I think you’ll see what he;s saying makes sense!”
>You blow air out of your nose.
“Oh sure, s’not like Twilight herself, the smartest pony I know, told that colt he was talkin’ nonsense or nothin’. I’m sure he makes complete sense to you little sis.”
>She scrunches her muzzle angrily at you, “And what’s that supposed ta mean!?” she growls.
“Oh nothin’, certainly ain’t saying y’all have a little crush or nothin’.”
>”I don’t have a crush on Anon I jus-“ she growls out of frustration and the flush on her face only grows, “Well at least I know what light is you dummy!!” she shouts before stomping off in the direction of the old barn.
>You sigh, she can be so impressionable at this age.
>Psh, like you were any better when you were that young.
“Alright alright! I’ll come take a look okay?”
>”No! You can just stay there and kick some apples for all I care anymore!”
>She’s got that same fire you did when you were that young too.
“How am I ever gonna learn what that colt thinks light is then?” you respond while trotting up to your little sis.
>”It ain’t “what he thinks it is” it’s what it is” she corrects you.
>You shake your head, while behind her, and follow her back to the old barn.
>”Anon!” Apple bloom calls out for the human houseguest you Apples have been hosting for the last number of months.
>”Over here Bloomy!” Anonymous calls out from the back of the barn.
>It’s more like a bundle of planks than a barn at this point and mostly was used for keeping broken equipment until another Apple wanted to take it off your hooves.
>This colt really didn’t seem to mind when he stumbled upon it a few months back and asked if he could use it.
>Weren’t no fur off your back at the time, but seeing how much he’s influenced your little sis, maybe it’s about time you really put your hoof down.
>Reaching the back end of the barn, you both spy Anon trying to hammer a thick nail into a rod of wood.
>What in tarnation is that fool colt thinking?
“Anon! Y’all stop that right now before ya hurt yourself!”
>In one swing he punches the thick nail through the rod before looking up at both of you, “I’m sorry? I was a little focused on my torque display that I did’t catch what you said.”
“Uh, I-I said-“
>”Oh, Hello also, Applejack. Didn’t mean to be rude there, how is your day going?”
>Thank Celestia for his scatterbrain, big colt is always having all these drifting thoughts, and you’re going to use this one to get out of that conversation.
“Uh, I can’t complain. Celestia’s giving’ me a beautiful day to work in.”
>Anon’s face shifts for just a moment, he flashes you a frown before quickly returning back to a casual smile.
>”Oh yes, "Celestia’s sun” sure does some wonderful work doesn’t it?”
>You flash him a smug look.
“It sure does! Just like Luna’s moon.”
>Yakheaded colt still can’t let go that Twilight dismissed his little “Gravelty” talk.
>”Buuut Luna’s moon can’t make light like Celestia’s sun right? And without light y’all wouldn’t be able to work would ya Applejack? And I happen to know what light is” Applebloom chirps, trying to change the subject.
>You both glance down to her as she trots over to the backdoor of the barn and waves you both over, “C’mon!”
>”What’s all this talk about Luna’s moon not making light? Course it does! She even changes the shape every so often.”
>Anon sighs, “Why don’t we just follow Applebloom first. Small steps I’ve realized are the optimal route in this world.”
>Fancy talking colt, probably can’t even explain it.
>”Over here!” Applebloom calls out next to come kind of wooden box.
>You both meet her over by it and she motions for you both to sit down.
“What’cha got there little sis?”
>”It’s a… uh…”
>”Dou-“ Anon begins to whisper
>”Double slit experiment box!” she continues
“A WHAT?!”
>”Now now Applejack, let’s just hear her out!” Anonymous says with hands. outstretched to you.
“My sister ain’t no filly fooler! You damn colt and your weird box can ju-“
>”SIS! It ain’t like that! Just listen for a few minutes!”
>Your blood is boiling, bucking legs are getting antsy already.
“FIne. I better not regret not already smashin’ this box after a few minutes” you growl.
>Applebloom sighs and Anonymous seems to relax slightly.
>”Okay so… uh the first thing is… the first thing…”
>”Light” Anonymous whispers.
>”Oh yeah, Light! Where does it come from?”
>They both look at you.
“Can come from a lotta places, most of it comes from Celestia's sun” you respond with emphasis on the last two words.
>”R-right... But do you know what it is?”
“S’light ain’t it?”
>”That’s what it’s called.”
“It’s… uh…”
>You’ve never really thought about it before.
“It’s sunshine… when it comes from the sun. Then it’s uh, fireshine when it comes from fire?“
>”You see! Tough to say right? Well what if I told ya it’s a wave?”
>A wave?
“Like the ocean?”
>”Kind of, water is a really good way to show it, but it’s more like…”
>Anon pinches two fingers on each hand and slowly pulls the apart from each other.
>”A rope! A rope that stretches from whatever’s makin’ the light to your eyeballs. It can be a really thick rope, what bright is, or it can be a really thin rope, what dim is, or the rope can be cut before it gets to you, and that’s when it’s dark.”
>Anonymous nods along happily, while you’re just tryin’ to make sense of the whole thing.
“So y’all are saying I’m seeing the end of a long rope when I’m seeing light?”
>”Uh huh!”
>They’re trying to play you for a damn fool.
”That all sounds like a bunch of horseapples. Light is just light, I ain’t never seen a rope or nothin’! And what’s that got to do with the ocean anyway?”
>”Not the ocean big sis, a wave. Y’all know how you can whip a jumprope up and down like the ocean right?”
>You imagine the up and down movement of the rope and nod.
>”Well that’s how light is, it’s not a straight line it’s a uh-“
>”Rep-“
>”Repeating pattern! So it travels through the air like a wave.”
>Now they’re talking jumpropes in the air?
“So what’s your dyke box got to do with any of this?”
>”Sis!” Applebloom says with a heavy blush on her face, “D-don’t be like that! It’s not a dyke box it’s- well just come here!”
>Your just being’ honest, ain’t right to forgo a herd.
>You roll your eyes and step up next to the box.
>It’s nothing spec-
>Oh, there’s some kind of small hole a-
>”It’s for lookin’ through sis, ain’t no pony underneath it neither” Applebloom says before you can even ask.
>”You see up above the hole I made two little cuts into the box too right?”
>You follow her hoof and see there are two tiny slivers in the box as well.
“You made this?”
>She nods happily, “Anon showed me what to do, but I put it all together m’self!” she chirps.
>Colt was too scared to do some mare’s work so he got your little sis to do it for him.
>Don’t know whether to be proud of your sis, or ashamed that Anon would use her like that.
>”Now, what do y’all think you’re gonna see on the other side of the box” Applebloom asks while putting her hoof over the eyehole.
“I’m gonna see two little lines of light inside the box, same as it is when Mac’s patching up any of the barns and there’s gaps in the wood.”
>Her grin has never been wider, “Okay, why don’t y’all take a look then.”
>If she makes you look at another mare’s p-
“What in Equestria!?”
>That’s not two lines!
>That’s not two lines at all!
“What- how?! And there’s even… why are there rainbows? Did Rainbow Dash get you some to splatter inside this here box? What is this?!”
>”It’s science sis! The light’s comin’ in to the box like a wave!”
“I don’t see no jumpropes or nothin’ all I’m seeing is a bunch of dots! That don’t make no sense!”
>”Maybe you should show her the water Bloomy” Anon says from somewhere behind you.
>You glance up to see his face looking down at your with a soft smile while Applebloom can barely hold back her excitement.
>”Yeah! I almost forgot I even brought up the water! C’mon sis, I have the perfect way to prove what y’all were lookin’ at.”
>You take one more look into the box and find that it’s still showing the same thing.
>Until it doesn’t and you can see just one line normal sunlight.
“What in tarnation?!”
>You look up form eh box and see Anonymous blocking one line with his finger, “Looked like you expected just then didn’t it?” he asks.
>There’s no hint of smugness in his voice like most colts would have, no sing-songyness either.
“But... how?”
>He chuckles, “Why don’t we see what Applebloom has to tell us, then maybe you can try putting it together” he says while motioning towards the lake where Applebloom went.
>Well he’s still got that “I’m not gonna tell you” bit that most colts have...
>You follow Anon down to the Apple family lake, Applebloom is already there and she’s fiddling around with some of Pinkie’s “ball emergency” balls.
>She tosses one out onto the lake and it floats nearby.
>”Anon! Sis! Over here!” she calls even though you can both see her clearly.
>She’s bouncing around to the other ball, making sure the rope tied around it is still good it seems.
“I ain’t never seen her so excited about something that isn’t involving crusadin’.”
>Anon shrugs, “It started out as a cutie mark attempt, I like to think it’s become more than that. She’s asking more and more questions at least.”
“And y’all are fillin’ her head up with all that nonsense like gravelty.”
>”No, not at all! Just-“ Anon sighs, “Just hear her out, that’s all I ask Applejack. I’m so grateful that you’ve listened to her this long.”
“And what’s that supposed to mean?” you hiss.
>”Not many ponies I’ve talked to were willing to listen for as long as you have. Whether you do it only because she's family or put of genuine interest doesn’t matter to me, but it means the world to Applebloom right now, and for that I’m grateful.”
>You eyeball him for a moment, nothing about him is giving you the feeling that he’s lying.
>”Come on! I’ve got the balls right where they’re supposed to be” Applebloom growls while tugging on your tail.
>Guess she was calling you both over this whole time.
“Alright already, I’m comin’.”
>Applebloom clears her throat and turns around to face you, “So as you can see, these balls are floating in the water.”
>She motions a hoof behind her and you lean over to see that they are indeed floating.
>”Now, the water is pretty calm right now ain’t it?”
>”Yes it is” Anon responds causing Applebloom to smile at him.
>”But, if I start tugging on this here rope…”
>She whips her red tail around one of the ropes that’s dangling down from the nearby tree to one of the balls and begins tugging up at it.
>The ball rises and sinks in a rhythm that matches the one she makes with her tugging.
>You can see small circles flowing out from around the ball in a pattern that matches the bobbing.
>”Ya see, waves!”
“I see em, don’t know what all this has to do with any sunlight.”
>”I’m glad you mentioned it! Now if I can just reach this… eh, if I can-“
>She’s too little to reach the other rope with her forehoof.
>Anonymous rises from his spot on the ground and takes the other rope in his hand, “We’ll have to make a smaller version for you to use I think.”
>Apple bloom’s embarrassed blush lessens as she nods in agreement, “Yeah… this kind of explanation really only works for you.”
>”You’re doing great Bloomy, isn’t she doing great Applejack?”
>"Wh- Uh, y-yes. Y’all are doin’ fine Applebloom, I just still ain’t seen’ it.”
>Applebloom looks from you to Anon to the water, “Oh! That’s cause I ain’t explained it yet.”
>”Both Anon and I are making our own waves in the water right?”
“Yeah.”
>”And I said earlier that light is a wave right?”
“I heard it with my own two ears.”
>”Then take a real good look at the water, do you notice anything different?”
>You step up to stand between Anonymous and Applebloom.
>Water don’t look no different, they’re just making the same circles in it like bef-
>Wait a moment…
“Now ain’t that somethin’.”
>”What is it? Oh, I mean… Yes! You can see the cons- const- uh… the waves are working’ together sometimes and sometimes they ain’t.”
>You watch the ripples travel through the water, it’s only when the sunlight’s hitting it just right that you can see it well.
>”S’kind of like us Apples buildin’ a barn. When we work together the barn gets built super good, but when some Apples decide that we need to build fences also then everypony starts buttin’ heads and don’t nothin’ get done. That’s how I think of it anyway.”
>You’ve been to a number of barn raisings that have gone both ways.
>Funny to think that little waves on water could be like barn raising.
>But sure enough it’s happening inside your mind.
>That ripple was the Apple Fritter raising, that gap is the Appeloosa disaster, and so on.
>”So, when I say that light is a wave, it has to work like these waves do too. Except instead of moving through the water it mo-“
“Moves through the air…”
>”Yeah! Tha- mmph!“
>Then the box is supposed to make it so there’s only two balls in the water?
>Does that mean the light fights itself as hard as you did your Orange cousins?
>The dots are bright, like the feeling of a barn raising done well.
>You recall the moment the dots disappeared into one solid line.
>When Anon blocked one of the holes.
>Then it’s like there was only half the Apples present.
>And while you Apples can get any task done everypony or no, but...
>When there’s all of you, even fighting or no it’s better than half.
>With all of you together though there’s a full spread of Apples, almost like a-
“Rainbow!”
>Anon glances up.
”No, not Dash, I’m talking’ about the rainbow inside your sl- two line box.”
>Still ain’t gonna call it a slit.
>”The rainbow is something I’m working on, I just need Pinkie to get back to me regarding an order I made with her sister” Anon responds while holding Applebloom's mouth shut.
>She wiggles out of his grasp, “So you see it too now right?!” she practically cheers, “Y’all know what light is!”
>It’s a wave, don’t get much clearer than that.
>Like a bunch of invisible waves that you can’t see because they let you see.
>Okay so maybe it’s not that clear.
“It don’t make a whole acre of sense, but I gotta agree with you sis, I can see what y’all are gettin’ at with your “waves”.”
>”I did it! I explained it Anon!” she says while bouncing around his feet.
>Anon kneels down and brushes his hand through Applebloom’s mane, “You did Bloomy, and do you remember what I said?”
>”Course I do! “If you can explain something so somepony else can understand it, then you must understand it pretty well”” she responds in as deep a voice as she can make.
>You spend some time asking’ a few more questions and even bobbing one of the balls yourself just to watch the same “barns” rise and fail along the water's surface.
>Before you know it Celestia’s sun is setting and it’s getting too dark to be able to use the box anymore and you help Anon carry it back to the old barn.
”So what’s that there rod for?”
>”Hmm? Oh, I’m working on a model-“
>”Model means a show” Applebloom chimes in.
>”Display Bloomy, I’m working on a display to show vectors, like torque.”
“That bat pony that just moved in?”
>”No, not Victor. Vectors. Vectors are… Well I need a free spinning wheel to really get into it, but it’s the next step up to gravity.”
>You stop yourself from rolling your eyes.
>After what you’ve heard and seen today, and going by how pleased Applebloom is, you’ve realized that maybe there is something to some of the things Anon’s saying.
>Dinner passes by much more actively than usual.
>Applebloom almost chokes on her food as she’s trying to explain how today went to Granny, three times.
>And soon enough it’s time for bed, and you’re all washed up and ready to sleep from a long day that was both physically and mentally trying.
>A series of small knocks sound at your door.
“Come in.”
>Anon stands in the now open doorway, “Applejack, I just want to thank you for listening to Applebloom’s “lecture” all the way through. I thought you would dismiss it early on like all the others have to me and I was wrong for having doubted you.”
“Ha, y’all could stand ta learn a thing or two about us Apples instead of your gravelty. Apples together, Apples forever.”
>He smiles warmly, “I suppose so Applejack.”
>That smile fades to a more serous look, “Back on my world families divided themselves over the pursuit of knowledge and of the refusal to accept it.”
>He steps closer to you, “So I’m asking this of you. Even if you don’t believe in the things I’m saying, please, don’t stop Applebloom from asking questions. From me, from Twilight, or even Granny Smith, let her learn as much as she can and draw her own conclusions.”
>You open your mouth to respond but can’t say anything.
>HIs gaze is one you’ve rarely seen in a stallion, if ever.
>They’re usually so distracted with simple thoughts like shopping, cooking, or how they look.
>This is something else all together.
“I won't.”
>That’s all you could muster.
>Just the truth.
>Satisfied with your response he bids you a good night and shuts the door behind him.
>You fall asleep while listing off questions you’ve never gotten the answer to.
>Maybe you’ve found the right pony to ask?