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Akano

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Blog Entries posted by Akano

  1. Akano
    I hate deadlines.
     
    There's a conference that my adviser wants my lab group to go to in June. Understandable. What's not understandable is that the deadline for abstracts to present at said conference is tomorrow (it was originally Friday, but got bumped back over the weekend). This means, of course, that I have to have enough data to write an amazingly short paragraph about what I'd be presenting at the conference by tomorrow. At 5 p.m.
     
    Now, I'm not one for stress. As my brothers and roommate can easily tell you, I take it rather easy and do not like to be rushed. This past week has been the exact opposite for me.
     
    So, I'm slightly burned out, but I have some data that will hopefully be enough to make an abstract with. Huzzah...
     
    On a more pleasant note, yesterday's Spike episode was good. I love Gummy. And Tank.
     

  2. Akano

    O HAI GUISE!

    By Akano,

    So, as you all may have noticed, I have disappeared off the face of the Internet for a time.
     
    But now I'm back at my college (classes don't start until next week, so I'm mainly doing research), which means I'm back on the Interwebs!
     
    Christmas was very nice; I got Tabasco sauce from my mom, Virtue's Last Reward (beat it in a week...and didn't realize that there was nothing more to the game after the end was over. XD) and the LEGOLAND exclusive set Forbidden Island from KopakaKurahk (both awesome), and Ramses' Return from Tekulo. I also got a smiley-face mug from my aunt.
     
    I also got to go to the LEGO store the other day and got Series 9 minifigures! I also got a few more Series 8 figs, so I may have to take pictures of those and review them at some point.
     
    Now you can expect a bit more activity from me since I'm back in the swing of things and somewhat out of "break mode."
     

  3. Akano

    Jackson E&M Final Progress

    By Akano,

    Saturday: Received final. Four questions pulled from Jackson and Griffiths' textbooks. Finished one problem (the Griffiths one).
     
    Sunday: Finished two more problems. I am on fire! Worked on the fourth problem. Way uglier than the other three.
     
    Monday: Woke up at noon. Haven't continued working yet. Hungry.
     
    This has been a look into the life of a grad student during finals week! Tune in next time where we see whether said student has eaten in the last three days!
     

  8. Akano
    I made it in GIMP. A cardioid is the envelope formed by a set of circles whose centers lie on a circle and which pass through one common point in space. This image shows the circle on which the centers of the circles in the above image lie. A cardioid is also the path traced by a point on a circle which is rolling along the surface of another circle when both circles have the same radius (here is a cool animation of that).
     
    What is the cardioid's significance? Well, it looks like a heart, which is kind of cool. It's also the (2D) pickup pattern of certain microphones (I have a cardioid microphone). If a sound is produced at a given point in space, the pickup pattern shows an equal intensity curve. So, if I place a microphone at the intersection point of all those circles, the outside boundary is where a speaker producing, say, a 440 Hz tone would have to be to be heard at a given intensity. So, the best place to put it would be on the side where the curve is most round (the bottom in this picture) without being too far away from the microphone.
     
    Another interesting fact about the cardioid is that it is the reflection of a parabola through the unit circle (r = 1. Here's what I mean). In polar coordinates, the equation of the above cardioid is given by
     

     
    where a is a scaling factor, and theta is the angle relative to the positive x-axis. The origin is at the intersection of the circles. The equation of a parabola opening upwards and whose focus is at the origin in polar coordinates is just
     

     
    which is an inversion of the cardioid equation through r = 1, or the unit circle.
     
    ♥
     

  11. Akano

    Pokédex 3D Pro

    By Akano,

    You look really cool, and I'm sure I'd enjoy your features and such, but you're $15. For a Pokédex.
     
    If you had 3D battling capabilities/games that would work in tandem with BW/B2W2, I'd probably get you, but you don't. Sorry.
     

  12. Akano

    Babs Seed

    By Akano,

    SUCH A CATCHY SONG ZOMG!!
     
    Also, the CMC were very adorable in that episode.
     
    (I watched it the other day, but just listened to the song for about the fifth time.)
     
    EDIT: Also, apparently typing in darkgoldenrod as your font color doesn't work anymore.
     

  14. Akano
    If you're building something and want to tell other people how to build it, it's useful to show the dimensions of said something (how big it is) relative to other things that people are familiar with. However, there are very few things in this world that are exactly the same size as other similar things (e.g. not all apples weigh the same or have the same volume). So, some smart people once upon a time decided to make standards of measurement for various properties of matter (which I think we can all agree was a smart decision). I wanted to talk about one of these today: the meter.
     
    The word meter (or metre for those who live across the pond/in Canada) comes from the word for "measure" in Greek/Latin (e.g. speedometers measure speed, pedometers measure steps, &c.), but the meter I'm talking about is the International System (SI) unit of distance. The original definition of the meter was one ten-millionth of the distance from the Earth's equator to the North Pole at sea level (not through the Earth). The first person to measure the circumference of the Earth was the Greek mathematician/astronomer/geographer Eratosthenes (and he was accurate to within 2% of today's known value) circa 240 B.C., so this value was readily calculable in 1791 when this standard was accepted.
     
    In 1668, an alternative standard for the meter was suggested. The meter was suggested to be the length a pendulum needed to be to have a half-period of one second; in other words, the time it took for the pendulum to sweep its full arc from one side to the other had to be one second. The full period of a pendulum is
     



     
    So, when L = 1 m and T = 2 sec, we get what the acceleration due to gravity, g, should be in meters per second per second (according to this standard of the meter). It turns out that g = pi2 meters per second per second, which is about 9.8696 m/s2. This is very close to the current value, g = 9.80665 m/s2 which are both fairly close to 10. In fact, for quick approximations, physicists will use a g value of ten to get a close guess as to the order of magnitude of some situation.
     
    So, you may be wondering, why is it different nowadays? Well, among a few other changes in the standard meter including using a platinum-iridium alloy bar, we have a new definition of the meter: the speed of light. Since the speed of light in a vacuum is a universal constant (meaning it is the same no matter where you are in the universe, unlike the acceleration due to gravity at a point in space), they decided to make the distance light travels in one second a set number of meters and adjust the meter accordingly. Since the speed of light is 299,792,458 meters per second exactly, this means that we have defined the meter as the distance light travels in 1/299,792,458th of a second.
     
    This is all nice, but it's not a very intuitive number to work with. After all, we humans like multiples of ten (due to having ten fingers and ten toes), so why not make a length measurement of the distance light travels in one billionth (1/1,000,000,000th) of a second (a.k.a. nanosecond)? That seems a bit more intuitive, don't you think? It turns out that a light-nanosecond is about 11.8 inches, or about 1.6% off of the current definition of a foot. In fact, one physicist, David Mermin, suggests redefining the foot to the "phoot," or one light-nanosecond, since it's based off of a universal constant while the current foot is based off the meter by some odd, nonsensical ratio.
     

  15. Akano

    Jackson ≪ Griffiths

    By Akano,

    I know most of you aren't physicists, but it's very important to me that physics education be designed to effectively teach physics to any and all audiences. After all, if you want people to have some inkling as to what you do, you want to be able to come up with a way to explain the necessities without getting bogged down in all the details. When you do this, it prevents the person you talk to from feeling like a moron and also allows you to talk about yourself and what you do to someone who has no clue what you do.
     
    This is why graduate-level texts frustrate me. The authors always assume that half the stuff they're discussing in their textbook is obvious to the reader/student who has maybe seen the material once before in an undergraduate course. While some of this material should be expected to be known already, you can't just chuck stuff at your reader and say "it is now obvious that" or "the proof is trivial" when neither of these statements is actually true. If you use either of these statements in your textbook, you're not a good teacher. Period.
     
    The title of this entry comes from the fact that I'm comparing two Electromagnetic Theory textbooks, one by D.J. Griffiths and the other by J.D. Jackson. Griffiths' Introduction to Electrodynamics is a witty, conversational, and informative text that helps undergraduates cope with the fact the E&M is really hard and that most of the concepts are foreign to someone who has only ever dealt with classical mechanics. Jackson's Classical Electrodynamics, on the other hand, is a text where the reader can tell that the author really knows his stuff when it comes to E&M, but has no sense of how to convey that knowledge to someone who is not an advanced student of the subject.
     
    For instance, let's say I were teaching the concept of projectile motion to someone who has never delved into the subject. If I were Griffiths, I would say something like, "All objects in free fall on Earth experience a force due to gravity toward the ground. This force causes all objects to accelerate at the same rate, meaning that the rate at which something speeds up/slows down in Earth's gravity is the same for all objects regardless of how heavy they are. Because this acceleration is constant near the ground, objects tend to follow a parabolic trajectory (if we ignore air resistance). The equations that show this follow from Newton's second law, F = m a. If you don't believe this, let's try it, shall we?"
     
    Now wasn't that nice? This explanation is certainly very clear about what projectile motion is and what causes it. Griffiths enjoys taking concepts that may be hard to comprehend and then following through with some equations/proofs to try and clarify the situation, usually speaking to the reader as though he were sitting down with them helping them through a problem.
     
    What about Jackson? He would probably say something along the lines of, "The reason projectiles follow parabolic paths is simple: if you solve the Hamilton-Jacobi equation in a uniform gravitational field, you will find that the path that minimizes the action is that of a parabola. This can be seen by setting the variation of the Lagrangian equal to zero."
     
    Well that was simple, wasn't it? While technically correct, you probably have no idea what the Hamilton-Jacobi equation or Lagrangian are, nor do you probably know what "action" means in physics. Now you may be thinking, "well, these things are part of undergraduate courses, right?" Well, no, actually. I had no idea what the Hamilton-Jacobi equation was until I took graduate level quantum mechanics, and I was expected to have known that from my graduate classical mechanics course (which I didn't take until my second semester of quantum mechanics). Suffice it to say, there was a lot I had to learn on the fly, but you can probably see what I'm getting at. The assumption that students know everything you expect them to know and have it ready to go the minute you throw that curve ball at them is a terrible way to go about teaching and, in my opinion, does not foster good education.
     
    On an unrelated note, I have a problem set out of Jackson due tomorrow which I haven't finished yet. So, how was your day?
     

  16. Akano

    Ponies Premiere

    By Akano,

    These villains are getting less and less backstory development as we go, huh? In terms of development:
     

    Sombra < Chrysalis < Discord / Nightmare Moon


     
    That said, though, I enjoyed the episode quite a bit. The songs were okay, but I've only listened to them once, really. However, it was nice for Spike to get a role as Twilight's supporting vocals. Cathy Weseluck amazes me.
     
    I did think Rainbow Dash was a bit over the top, but I enjoyed everyone else.
     
    También, sombra = shadow en español, por tu información.
     

  19. Akano

    Pokémon White 2: Postgame

    By Akano,

    While I technically beat the Elite Four on Tuesday, I thought I'd share my team here.

    Anubis (Lucario)
    Tornadus-T
    Vanessa (Emboar)
    Zoroark
    Tesla (Magnezone)
    Golduck - HM slave

     
    I couldn't nickname Zoroark due to it being N's originally, and Tornadus I just never got around to nicknaming after I got him from Dream Radar. This was actually the first time I've ever raised any of these Pokémon for a team, so it was a very different game experience this time around. I wish Lucario were just a bit bulkier, because he can dole out punishment but can't really take it. I love Zoroark's speed, but man is he frail. Emboar was all right, but I definitely prefer Samurott. Magnezone was pretty awesome, too; his Special Attack is beastly.
     
    I should raise a Chandelure when I replay through White. He looks pretty awesome...
     

  20. Akano

    Happy Halloween

    By Akano,

    (Click for larger image)


     
    The one on the left is my roommate's; the one on the right is mine.
     
    Happy Halloween, BZPower.
     
    (Also, check out my Haunted House review if you haven't already! It's full of awesome haunted house pictures!)
     

  21. Akano

    Sandy Update 3

    By Akano,

    (12:43 p.m. EDT) So, Sandy is currently doing his/her (its?) stuff outside my apartment. LOTS O' RAIN!
     
    No snow or high force winds yet, though. I think that stuff is being saved for later.
     
    In other GOOD NEWS, EVERYONE, I'm technically still alive.
     
    UPDATE 2 (3:40 p.m. EDT): Winds have been picking up, rain is unrelenting, and my apartment is cold. This calls for hoodie & blanket times! 8D
     
    Wow, it's really raging out there...
     
    UPDATE 3 (10/30/2012 at 2:29 p.m.): Things have calmed down. This morning whilst being sleepily half-awake I heard cleanup trucks outside. At least two trees are down that I can see from my apartment windows. Fun stuff.
     
    Also, the power went off a couple times last night and this morning, but it's currently on (hence my ability to type this ).
     

  23. Akano

    Sandy

    By Akano,

    So, school for me has been cancelled Monday and Tuesday due to some sort of sandy storm that is also full of winds and snow (and may or may not be caused by Spongebob's rodent friend). The details aren't really clear. So, after removing things from my porch and storing lots of water in my fridge (at least five gallons worth, maybe more), I feel I'm ready to bunker up and watch it from the comfort of my living room.
     
    My roommate is thinking of going into school to do research. I am not terribly keen on the idea. So, Pokémon it is. 8D
     
    Also, that awkward moment when you're about ready to check out Christmas presents for siblings on Bricklink and a scheduled downtime occurs. :\
     

  24. Akano

    Equation of the Day #3

    By Akano,

    Just so everyone knows, I obtained the awesome LEGO Haunted House over Fall Break and have pictures that will work wonderfully in a review. You can probably expect that next week at some point (I hope). For now, let's go over another fun physics equation! This one is probably very familiar to you, though you may not have any idea what it means. I give you mass-energy equivalence:
     



     
    Where E is energy, m is mass, and c is the speed of light. It's a very simple-looking equation with only three parameters, but what does it mean? Well, it means that anything with mass – you, your cat, your house, the Earth – has latent energy stored in it, and the amount of mass determines that latent energy. For an object at rest, this correlates to the rest mass of the object. If an object is moving really fast (near the speed of light) its kinetic energy causes it to actually get heavier, since the object can never actually reach the speed of light (only objects with no rest mass move at the speed of light).
     
    So, if we have an object sitting and doing nothing, and it suddenly glows for a split second, then stops, where did the light come from? Well, light has energy, as we know, so we could calculate the energy of the light that escapes our object. If the light emanates in all directions, then the net kinetic energy of the object is unchanged. But conservation of energy says that energy can neither be created nor destroyed! Have we violated the laws of physics with our weird glowing object? Well, no, because if you were somehow able to weigh the object pre- and post-glow, you would find that the mass of this object is actually slightly less after the light is given off.
     
    But wait! Doesn't conservation of mass say that matter can neither be created nor destroyed? Well, yes, it does say that. So the only way for this to make sense is if the mass is converted into the energy that was emitted. We know that energy can be converted into different forms (electric, mechanical, thermal, etc.), so this must mean that mass is another form of energy that can be converted to and from! Pretty neat, huh?
     
    Minutephysics has a cool video on this with a bit more technicality and pretty pictures of radioactive cats, but this is my text-based explanation simplified.
     
    Another thing that may cross your mind is that this looks very similar to Newton's second law:
     



     
    So, does Newton's second law equate force with acceleration? Well, no, because in the mass-energy equation, the constant of proportionality, c2, is a universal constant; it is the same for any and all objects in the universe. The mass of an object, however, varies from object to object, and is thus not a fundamental, universal constant, so while these equations are similar and relate two seemingly different entities, they do not conceptually perform the same task.
     

  25. Akano

    Equation of the Day #2

    By Akano,

    I had a wonderful time today; I got to see old friends from my undergrad today and went exploring a corn maze; it was a lot of fun.
     
    Also, equation of the day: Newton's Second Law
     



     
    where F is the net force, a is acceleration, and m is the mass of the object in question. It's such a simple-looking equation, but it contains so much physics. Want to know the path of a free-falling object subject only to the force of gravity? You use this equation. Want to know the attractive force and classical orbit of planets/atoms? You use this equation. Want to know the physics of a car skidding on pavement? You get the idea.
     
    This equation is a staple of physics and is used extensively in intro and classical physics. Newton, you clever devil, you.
     

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