Archive for July, 2008

The end of my addiction

Posted in Uncategorized on July 29, 2008 by quantummoxie

Facebook just took down Scrabulous. ūüė¶ While Hasbro was certainly legally right, it was a PR blunder. They would have been better off working with the Scrabulous creators since the latter was an improvement on the original.

The physics of baseball: batting

Posted in Uncategorized on July 28, 2008 by quantummoxie

Since I’ve gotten back to playing ‘ball’ (softball) this summer I’ve been thinking a lot about my hitting. Once I got back to playing second base I fell into my old routine with fielding and have played fairly well (2-3 total errors in six games) even though I’m playing softball this summer and I used to primarily play baseball. Second base seems to come fairly naturally to me. My hitting, however, is another matter.

When I played baseball I was never a great hitter. During my first stint at softball I had a solid on-base percentage (OBP) and usually reached on a hit, though the vast majority were singles. But that was a college ‘beer’ league. The league I’m in this summer is a very competitive co-ed league and my hitting has taken a subsequent turn-for-the-worse. Somewhat concurrently I have been coaching T-ball which is the entry-level game in little league. Despite being average I always prided myself on having ‘good form’ and, as a teacher, have worked hard teaching these kids how to swing (no one keeps score in T-ball since it’s really about learning the fundamentals).

Put all this together and I started to think seriously about batting. While this may be known to those who have been involved with the game for a long time, I realized that the advice I (and countless others) have received (and given) to ‘choke up’ on the bat, is bad advice. Physics – and a little common sense – tells us why.

When a person bats they’re (usually) seeking to maximize the force of contact between the ball and the bat through efficient use of their body. Since the person is swinging, the action is akin to pulling a lever. That is, something is (approximately) rotating about a point or axis. There are a lot of variables that go into this, but roughly the force of contact is related to a torque created by the motion of the arms and bat (as well as a portion of the torso). The strength of this force partly depends on the distance, r, the contact point is from the axis of rotation. Take a look at the picture below that I’ve doctored up a bit (Note: I found this on Flikr via a Google search and it apparently was taken by a guy named Wil C. Fry. Hope he doesn’t mind.).

So the torque at the point of contact, independent of the action of the ball itself, is \tau = I\omega where I is the moment of inertia for the bat/arm combination. Roughly, we can approximate it as a cylinder pivoting around one of its endpoints. This is not a perfect analogy, but it will work for the argument here. \omega is the angular velocity of the bat/arm combination, i.e. how fast the batter swings the bat. So the torque can be determined without even considering the ball. However, the contact itself also creates a torque since torque also happens to be \tau = \mathbf{F} \times \mathbf{r}. Note this is a cross product. That means only the components of the force and vector, r, that are orthogonal (perpendicular) to one another multiply. If you’re not sure about that, let’s assume the batter hits the ball dead on (i.e. he/she didn’t swing late or early – no pulling or hitting to the opposite field). In that case it’s just a regular multiplication. So if you know the torque from the other stuff and you know where the bat and ball connect, you know the force of contact. Essentially, this is the same principle behind closing a door. Remember, the batter is trying to get the ‘biggest bang for the buck,’ so-to-speak. When you close a door you need to push harder to get it to close the closer you push to the hinges. Don’t believe me? Try it. This is why you should hold wrenches and hammers as far from the head (as close to the end of the handle) as possible. Hitting a baseball is a lot like hammering a nail.

This summer, despite my team’s plethora of bats, not one is less than (nor greater than) 34 inches in length. Now, I’m not a big guy (5’8″) and was always taught to either use a shorter bat or to choke up. Take a look at our picture above again. Na√Įvely we might assume that choking up might help the fellow. Of course, for the guy in the picture, the ball’s likely to just hit further down the bat. But for someone like me, who seems to always make contact on the tapered part of the bat, this is seen as an improvement (the ball tends to go more where you want it to, for one). But, this summer, despite choking way up on the bat, contact kept happening along the tapered portion most of the time (not to mention the fact that choking up just doesn’t feel natural). Then someone told me to not choke up, but instead move further back in the batter’s box. Let’s assume the ball always goes right over the plate for now and let’s only consider times I actually make contact. In this case, moving me back has the effect of increasing r! Just like closing a door, that either means I don’t need to swing as hard to get it to do the same thing, or, if I swing just as hard, it should result in a larger force of contact (think about using the same force to close a door by pushing right next to the hinge and likewise by pushing on the handle). In my last at bat (AB) in my most recent game, I did not choke up, but rather moved back further in the box (assuming the umpire would tell me if I was outside the box) and laced a nice single to left-center.

Now, my teammates were also talking about the fact that many batters actually ‘choke down‘ on the bat to get more power. Specifically, the very bottom of the bat is gripped by either the middle or ring finger of their lower hand, leaving one or two fingers gripping at air. Then, right around the time of contact (ideally at the time of contact), they flick their wrists a bit (the grip simply makes this action a bit easier). This applies a secondary torque since, briefly, the bat is also pivoting around its base (in addition to the bat/arm combination pivoting around the axis along the body). Since torques and forces are additive, this increases the force of contact slightly. It’s a nifty little trick of physics – if you can get the timing right. Get it wrong and you’re likely to pull the ball foul.

Now we could also look at all of this from the standpoint of momentum. In the above case, the momentum of both the swing and the flick of the wrist is associated with some angular motion and is thus called angular momentum. Nonetheless, a linear momentum is associated with this at the point of contact and, like forces and torques (and, indeed, all vectors) momentum is additive. This helps explain one more trick batters often use. Frequently batters will, just before their swing, pick their leading foot up and step forward a bit as they swing. This effectively transmits a small amount of linear momentum to the entire body and thus to the contact as well. This gets added to the other two pieces of momentum and, if perfectly executed, is the recipe for a great hit.

Ah, but how does one perfectly execute something like this? Well, it’s all about timing. Take a look at the following analysis based on numbers crunched by Yale physicist Robert Adair. Granted, this is for a 90 mph fastball. In theory it should be easier in slow-pitch softball, but in the latter the ball is not coming directly toward home plate (if it is, don’t swing – it’s a ball since it has to arc to be a strike in slow-pitch). In any case, at least in baseball and fast-pitch softball, timing, which is largely physiologically determined, is what separates a good hitter from a great hitter.

Update: I wanted to clarify the first torque equation (I wrote this when I was exhausted). So, if we approximate the bat/arm combination as a cylinder rotating about one of its ends, then the moment of inertia would approximately be ^{mL^2}/_3 where L is the length. Let’s, for the sake of argument, assume that the ball makes contact with the bat at the very end of the bat every time. As such, we can approximately say that L \approx r. According to Adair, the bat is moving at about 80 mph when it hits the ball. That’s a linear velocity. Angular velocity is ^v/_r where v is a linear (tangential) velocity. Substituting all that stuff in, the torque becomes \tau = ^{mLv}/_3. Thus we see that if we choke up, we’re reducing L thus producing less torque and reducing the force of contact!

Nuts in Buffalo: funeral + reunion = wild & crazy fun!

Posted in Uncategorized on July 27, 2008 by quantummoxie

I’m in Buffalo this weekend (hence no posts in awhile) with Mrs. Moxie, the kids, and the dog visiting my folks. Yesterday we began the day with a memorial service for my grandmother who passed away a few weeks ago at the age of 91. That was followed by a 20th reunion of my 8th grade class – yes, someone decided to organize an 8th grade reunion. It was actually a lot of fun.

Anyway, I have an enormous family. My mom is the oldest of seven and, while my dad is only one of three, there are lots of cousins. Plus the two families are close. So this weekend has been like a huge family reunion – except that we all saw each other three weeks ago at my sister’s wedding (after which Mrs. Moxie, the kids, my parents, and Mrs. Moxie’s parents took a week’s vacation together – and it wasn’t the first time)! Nonetheless, it is always an experience getting my family together since we’re all nuts. The good thing about this is that there is always a lot of laughter. At one point we had eleven people sleeping somewhere in my parents’ house (“Don’t trip over Aunt Tina! Oh, that’s George??”). Since a lot of people had flown in we traded cars here and there and at one point people started to lose track of where all the cars were (“Who took the truck?”). Of course the food is always good. My mom’s family is Polish and Ukrainian, though, so it is frequently fattening. But I feel so lucky my kids have the opportunity to grow up in such a loving, warm environment.

Of course I also had this crazy 8th grade reunion yesterday. Who organizes an 8th grade reunion?? Well, that would be one of the nuts I went to school with (do you sense a theme here?). Perhaps the craziest thing is that, out of approximately 25 students from that class, 18 came to at least one event. We actually were a pretty close class in some respects (maybe it’s because we’re all nuts) but maybe never realized it at the time. In any case, it was a blast to see people after all these years, with their kids and spouses and other assorted and acquired attachments (e.g. my slight beer gut, gray hair, and bald spot – I suppose the latter is actually a lack of an attachment). I thus feel equally blessed to have grown up in a community where such an odd event is actually… well, not that odd. That is definitely something that is unique to Buffalo. There are nearly as many people in the Buffalo area as there are in the entire state of Maine and yet it’s like a small town – everyone seems to know everyone else. There is a little bit of that in Maine which is partly why I like it so much, but there’s nothing quite like Buffalo.

Online education & the uniqueness of Maine

Posted in Uncategorized on July 20, 2008 by quantummoxie

Opinions of online education vary greatly. Certainly some of it has fallen prey to the rampant consumerism that has dominated so many other ‘markets.’ But some of it truly serves a very important purpose beyond the old-fashioned correspondence course roots from which it has grown. Perhaps no place is that more apparent than here in the very unique state of Maine.

I was reading the latest Down East and came across an article about the island of Matinicus, officially known as a plantation in Maine, that happens to be the furthest permanent settlement from the mainland. During the height of summer traffic, the ferry from the mainland visits the island four times per month. The island has no store or restaurant, but the article briefly mentioned a visitor (or anyone else, for that matter) could buy fresh baked goods from island resident Eva Murray, a former student of mine.

As it happens, I have, for about six years, been teaching online courses in astronomy and the history of mathematics for the University of Maine at Machias. Over the years I have had students like Eva from some fairly out-of-the-way places (mostly, but not always, in Maine) such as Swan’s Island, Jackman, and even Timbuktu. Most of my students (including those from the last three locations I listed) have been teachers who needed their teaching credentials re-certified. In Maine, recertification requires taking courses from post-secondary institutions. While Maine has a fairly well-distributed public college and university system, there are still numerous places – like the ones I mentioned above – that are physically very, very far from any such institution. This is probably more true in Maine than in any state east of the Mississippi (for instance, the majority of Maine towns are actually officially known as unorganized territories – while Maine is ‘only’ 38th in population density compared to other states, we’d be even lower if you didn’t count the two southernmost counties). Maine has settlements that are inland that are really only reachable by float plane! (I’d give a link to Clayton Lake, but there really isn’t a meaningful one that I could find).

So, it is in this sense that I think there is a genuine need for good, quality online education. While I may not be teaching these online courses much longer due to a growing number of other obligations, I hope that in some small way I have helped these communities, perhaps to preserve their way of life in a rapidly encroaching world.

Is string theory bad science or just bad for science?

Posted in Uncategorized on July 14, 2008 by quantummoxie

Friday night I went, as usual, to the monthly meeting of my local astronomy club, of which I have been a member for many years. A friend of mine, for some inexplicable reason, had brought in a supposed psychic to speak about this whole 2012 thing. I’ll spare the gory details but I will note that she kept saying science was starting to prove her right (though she never elaborated). At one point someone asked a question about multiple dimensions and string theory and paranormal stuff or something like that – I had tuned out by that point (Note: I am somewhat open-minded about such things, but only with hard scientific evidence).

In any case, it nonetheless got me thinking that string theory has taken on a life of its own and become something that is bad for science – or is it just bad science period? String theory’s major problem is that, because it has never been tested in a laboratory (at least directly), no one really knows which of its crazy predictions is true. And many aspects of the theory are, in fact, not directly testable by definition! Now, there are plenty of theories out there that haven’t been tested yet including this stuff on closed time-like curves (i.e. wormholes) some of us have working on. But there are several differences.

First, our work is intended, primarily, to investigate some side problems in quantum information and quantum computing and we explicitly make it clear that the concept of a closed time-like curve is highly speculative. In other words, it’s a nice theoretical laboratory for testing some more mainstream ideas, but we realize that, in itself, it’s out there a bit. String theorists, on the other hand, thing their wackaloon ideas are Gospel.

Second, we’re not media hounds (at least in relation to this stuff). The string theorists (e.g. Brian Greene) have done such a good job selling their theory that over the past 15 years or so it has become the face of theoretical physics (which is utterly absurd since it is only a small portion of it). They then have no trouble appearing on TV and radio shows whose sole purpose seems to be an improved Nielsen rating and will happily let their imaginations run wild on the air while unsuspecting viewers and listeners start to think this is more than just speculation.

In the end the media blitz perpetrated by the string theorists over the past 15 years has done little or nothing to help the public understand the scientific method since the public is left (or even guided, in some cases?) to think that things like ghosts and paranormal experiences are evidence in support of string theory. Even if string theory turns out to be correct, the media blitz it has triggered has only muddied the notion of what science is and how it operates. In that sense, string theory has been very bad for science.

But is it bad science itself? I say, at least in part, yes, since aspects of it are not testable by definition (i.e. if the strings really are smaller than a Planck length there should be no way to ever confirm their existence). Developing a theory that is impossible to test, one way or another, smacks of religion in my book and, to me, that’s bad science.

Let’s hope, then, that people like Lee Smolin continue to challenge its supremacy in the mainstream media. Unfortunately, the best way to battle this would be to find an anti-string theorist who was as big a media hound as Brian Greene. Hey, CNN, I’m available!

Were they really that dumb in the dark ages?

Posted in Uncategorized on July 9, 2008 by quantummoxie

Ran across this post over at Strange Maps.¬† I always wondered if they really underestimated the earth’s circumference or if that was an old wive’s tale on par with the one that assumes they all thought it was flat.¬† I mean, Eratosthenes of Cyrene estimated the earth’s circumference to be 25,000 miles in 250 BC!¬† (It’s actual circumference is 24,901.55 miles at the equator and 24,859.82 miles around the poles).¬† If it was true (which I assume it was) that Toscanelli severely underestimated the earth’s circumference, it was likely due to faulty – as in Aristotelean – reasoning.¬† And these boneheads want to take us back to that!

Big gov’t, the new rich, and Plum Creek

Posted in Uncategorized on July 5, 2008 by quantummoxie

Turns out the obscenely greedy Plum Creek is at it again.¬† We’ve been battling a large development plan of theirs in Maine for some years now up near Moosehead Lake.¬† I never realized just how big and insidious they are, however, until now.¬† Since just about everyone in Washington (DC, that is) is in bed with large corporations, it comes as no real surprise that someone from the current administration made a deal with Plum Creek behind closed doors that would destroy vast swaths of undeveloped timber land in Montana.

Ironically, environmentalists are pining for the days when timber companies were actually loggers and miners and not real estate developers.¬† As someone put it in the article, clear cuts can at least grow back.¬† What Plum Creek is proposing here is large gated communities of homes for the wealthy.¬† How is it that they can propose such an enormous development in the midst of a housing crisis?¬† It’s because the new breed of super wealthy are largely unaffected by the current economic downturn (and we’ll get to why in a minute).¬† So these homes that are being proposed will generally serve as second, third, or even fourth homes to most of their owners who will spend little actual time there and, in the process, further diminish wildlife habitats and close large areas to hunting and fishing.

So why is the economy not affecting this new breed of super wealthy?¬† Call it a gut feeling or call it that growing paranoia that comes from being a libertarian (or is it the other way around?), but it seems to me that we’re entering a new type of economy.¬† Traditionally, the wealthy relied on the less-well-off as both the source of their labor as well as, in many cases, the consumers purchasing their goods.¬† But now it seems as if the super wealthy are becoming self-supporting.

Automation and outsourcing are increasingly reducing the supply of manufacturing and even service industry jobs and while fewer products are directed at the average citizen.¬† Certainly this is a small portion of all the goods are jobs out there, but points to a disturbing trend – the wealthy don’t necessarily need the rest of us anymore.¬† As such, they can buy up all the land and force everyone else out.¬† It has been happening here in Maine for years – rapid gentrification such that not just working class families but also middle class families find living here to be difficult.¬† I like to call it Aspenification after Aspen, Colorado where even the town’s doctors and lawyers supposedly must live elsewhere and commute since they can’t afford the cost of living in Aspen.

So, despite the housing crisis, the super wealthy can still buy homes, cars, etc. with abandon.¬† Despite being a libertarian, I think something needs to be done about this.¬† The trouble is that in order to get to Washington to begin with, you have to get into bed with corporations and you have to be wealthy.¬† Face it, does anyone in DC really understand what it’s like to try to make a living these days?¬† Democrats and Republicans alike are so utterly out of touch and don’t really care since they know the system is such that if they lose someone just like them will be elected instead.

But what is the solution?¬† It is definitely not federal intervention in the traditional sense since there seems to be less difference between federal government and corporations than ever before.¬† So, for instance, I am – as are many Mainers – utterly opposed to a North Woods National Park up in northern Maine.¬† Many outsiders see it as a way to preserve the wilderness (which really is working forest and not true wilderness).¬† But many Maine residents correctly see a National Park as suddenly opening the flood gates to streams of RVs, poor forestry management practices, drilling, and other things.¬† The Feds would do better to put more power in the local populace.¬† As the article above shows, the people who actually live in that part of Montana are by and large opposed to this plan.¬† Unfortunately they don’t seem to have a voice.

Damn, I sound like a liberal.¬† Well, at this point I don’t care.¬† Things like this only do more to fuel the greatest divide in this country – and perhaps the world – right now: class differences.¬† There was a time when the classes needed each other to survive.¬† That time seems to be fading.