Blog Index
ComputersThe long-awaited new laptop has arrived at last!
By 'long-awaited', I'm referring to how long I've wanted a new computer and saved for it. I definitely don't mean how long I've waited, after ordering, for it to ship: it was only a week ago today that I placed the order! Since they say it takes 1-2 weeks just to configure it usually, I'd say that's not bad at all.
Here are some relevant specs:
Intel Core 2 Duo 2.0 GHz, 2 MiB L2 cache, 800 MHz FSB
2 GiB RAM
120 GB 5400 RPM hard drive
8x DVD burner
nVidia Quadro NVS 140M, 128 MiB VRAM
15.4" WSXGA+ widescreen, 1680x1050 native resolution
3x USB 2.0 (1.1 was incredibly slow with large amounts of data)
IEEE 1394 (Firewire)
Sundry other features (some kind of card reader, keyboard light, wireless internet, etc.)
There are tons of intangibles about this machine that I just love. The craftsmanship is head and shoulders above the competition -- it's a solidly built machine. (After owning a Dell for 3 years, I came to realize that's important to me!) The sound is surprisingly clear for laptop speakers. And it's so incredibly quiet, too! When I turned it on for the first time, I couldn't even tell whether it was on when I closed my eyes. Last night I thought it was getting rather loud; turns out, the noise was from my other laptop several metres away.
Far and away, the biggest downfall of the computer is Windows Vista. The OS is simply not ready for prime time yet. My system is a beast, and once Vista boots up it runs it well, but it seems to take forever to boot up in the first place. I've even had a blue screen of death already! And several of the features just don't work.
The reason I'm keeping it instead of 'downgrading' to XP is to keep an eye to the future. I've no doubt that, in the 3+ years I'm guaranteed to have this laptop, MS will tweak and patch to the point where Vista's a decent OS, like they did with XP. I'd rather just keep slogging away with Vista until they do.
Of course, what will make it bearable will be the 'other' OS on my system -- Gentoo Linux. I can't wait until I get it installed so I can actually start getting stuff done on my computer. I've never dual booted before, but Thinkpads are supposed to be awesome for Linux and I have extensive day-to-day experience with Gentoo.
In the meantime, at least I have the machine in time for the NIST trip in a week, and the MMM conference at the beginning of next month, where I'll be giving a talk!
BaseballIf somebody told me a month ago that I could have:
- My favourite team of all time, the Cleveland Indians, advancing to the ALCS
- The hated Yankees eliminated from the postseason in the first round, once again
- A bonus paycheque of $147.35 because of it
I would have flipped out. Last night, though, that's exactly what happened!
Well.. almost. Technically the cash is just a refund, because that's how much I paid for four tickets to game 5. With the Tribe taking the series in 4 games, that game will no longer be played, so I should be getting my money back pretty soon. Of course, the downside is that I miss seeing probable Cy Young winner C.C. Sabathia in a playoff game at the Jake, but I'm glad because this lines up the Tribe's pair of aces for the ALCS against the BoSox. (Not to mention, having just ordered a new Thinkpad, I could frankly use the cash at the moment!)
Here's to the 2007 Indians -- the best Tribe team I've ever seen, who have a great shot at taking the World Series!
Of all the things I've ever done, few are as silly as setting the world record for the memorization of e.
In January of this year, the discovery of the Pi World Ranking List rekindled an old hobby of mine from the beginning of highschool -- the memorization of the decimal places of pi. I soon found that there was also an e world ranking list, and that the record was much more accessible! (777 places is a lot easier than 100,000.)
I soon started working on both pi and e. I never got as far with pi as I had in highschool (fell a few hundred short), but once I started focusing exclusively on e, progress was swift. I was memorizing as many as nearly three hundred digits per day at my peak, with a clear goal of 2718 places ("e" thousand) on 2/7 ("e" day).
Then, the real world intervened.
I quickly found that, perhaps unsurprisingly, my mental energy was being sapped by this worthless endeavour. I couldn't concentrate on my research enough to get anywhere. So, I forgot my goal, got a few friends from church together, and just recited what I had so I could make the list. I ended up reciting 1590 of them, and it was good enough for the record!
Of course, I knew it wouldn't last more than a few months. Sure enough, I just got an email from the keeper of the List, letting me know that my record had been broken. The new record is currently 1810 digits, and when it gets broken it won't be by me. It is enough for me that I was the best that anyone had ever been at something very silly, even if only for a short while.
That said, I am a sucker for Pi day, and I crammed as many digits as I could in the 40 minutes prior to the recitation contest. I ended up being able to recall 1000 even, which gives me one more dubious distinction -- I'm officially the first member of the 1000/1000 club, having officially recited 1000+ digits of both pi and e.
While it was a fun challenge, I can't help but long for a more useful hobby. To that end, I've finally started pursuing a lifelong dream of becoming competent with electronics. Right now I'm doing basic circuit theory, but eventually I want to become an expert in both semiconductor devices and wireless communication. At least then I'll have something to show for my time!
SchoolThis past Monday was the culmination of three weeks' worth of frenzied studying, learning everything I could about gravitational waves. Rather a tall order, since I never took a course in general relativity to begin with, but I digress. Once I'd given my 20-minute, no-notes talk, and braved the following 60-plus minute question period, all that was left was to wait.
Yesterday the faculty met to decide everyone's fate, and shortly thereafter came the news -- I passed my special oral qualifying exam! It was a real relief, since I didn't know whether I'd passed (I didn't ace it the same way I aced the written quals). Thus, all the hurdles are behind me, and nothing stands between me and doing my thesis research. The pizza and beer were well-earned!
It's exciting that things are basically in my own hands from here on out. I have the opportunity to really take charge, stay focused, and get my research done and thesis written in as few years as possible. I hope I can prove up to the challenge!
HumourWhile reading a story (on cnn.com) about the deplorable theft of an icon from a Greek monastery, I couldn't help but notice the unintentionally hilarious final sentence.
The stolen artwork was one of several famous religious icons in Greece, where offerings or votive gifts are left by worshippers who pray for recovery from illness or successful conception, or make other prayers.
(Emphasis added.)
I'll leave you, dear reader, to ponder the multiple meanings of that sentence.
ScienceI found a really promising book on Amazon the other day. It looks very relevant to my research, reasonably priced -- a perfect addition to my wish list, given the current status of our family budget!
On adding it to the wish list, I was greeted with a rather bewildering sight...
I suppose nanomaterials research, being a more advanced subject, tends to attract researchers from a more advanced stage in life. It's not inconceivable that some of them might have kids, for whom they also shop at Amazon. Or maybe they just really like animated films.
Either way, it's a pretty funny connection.
After weeks of continuous and unvarying disappointment in the results of my samples, I got a very pleasant surprise. The TEM came back from a recent batch, and the results are stunning. A beautifully monodisperse monolayer of particles, with long range ordering. It's the kind of monolayer picture I could present at a conference. And most surprising of all, I didn't even use the Langmuir trough! Nope -- it's just a single drop applied by pipet to a TEM grid.
All my best TEM pics are available in the TEM album. Unfortunately I never wrote the code to link directly to an individual image, so you'll have to hunt around. Should be pretty obvious which one it is, though, and the rest of the pictures are pretty too. Note the scale bar in the bottom left, which tells you about the size!
On June 17 of this year, Amy and I got married. No more Amy Lambert -- she's now Mrs. Hogg! The wedding was wonderful, as was the honeymoon; pictures to follow from each. Between work, studying for quals, and particularly my new family, that explains why blog posts will probably continue to be few and far between for the foreseeable future.
Every day, on my way from school but never to, I pass a sign with a sticker on it. The sticker says, "I'm pro-choice and I pray".
Now, the reason I'm bringing this up is not to explore the complex interplay between the abortion issue and people's personal religious beliefs. I just find it ironic that a One Way sign would be "pro choice".
I have two microwaves.
One is a newish Panasonic, which acts like it works great but in actuality doesn't heat things. It used to heat things, so I'm sure it requires only the most minor of repairs.
The other is an older model, with an analog dial instead of push buttons, and no rotating plate. However, I can personally vouch for the fact that it works great, since I've been using it for months on end now.
This weekend, Amy is moving her belongings into the apartment, one of which is a microwave nicer than either of these. So to make a long story short, I need to get rid of two microwaves as soon as possible, preferrably before June 17th.
Now, it would be a (relatively) simple matter to cart them down to the dumpster and toss them. But our society frankly wastes too much as it is, and doing that would make me sick. I mean, the one is perfectly functional, and the other could be made so with a small effort from somebody who knows what they're doing!
So I beg you: If you or anyone you know could use a microwave, please let me know. I'm in Pittsburgh now, but I can probably send them back to Grand Rapids with Amy, and from there I might even be able to arrange transportation to St. Catharines with people coming back from my wedding!
I just don't want perfectly good microwaves to go to waste.
I just got the email from Prof. Majetich. Turns out there is room for me in the nanoparticles group! It's a real change in direction for me, but I can't help but be utterly fascinated by the things. I'm going to be working on the Spin-NIRT data storage project. I get to figure out how to get nanoparticle monolayers to write to media, which apparently is quite hard. And in the process I will understand electricity and magnetism -- understand them, you see -- down to the very core of my being.
What follows is the text of a spam email which evaded the Carnegie Mellon spam filter. Notice how it scrupulously avoids any spam-like phrases. So, where's the message? In a black-and-white image file containing the text. Pretty clever. Enjoy!
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Creation and EvolutionI've been thinking again about the Creation/Evolution debate lately, and I think I've distilled it into one main question in my mind, one to which I've never heard a satisfactory answer (at least, from a Creationist). One can argue back and forth all day about this or that piece of evidence, and which side it "really" supports, but let's cut to the heart of the matter.
[i]Why does the Earth look old?[/i]
In other words, why is it that the sum total of mankind's knowledge on this subject paints a coherent picture of an ancient Earth? It would be bad enough if the preponderance of evidence merely seemed to rule out a 10,000-year-old planet, without being more specific than that. But we actually have strong convergence on a very specific age: 4.55 billion years. God, being omniscient, must have known that things would appear thus. So why would He give us one message with His Word, and another, contradictory one with His works?
Obviously, I've heard the question asked before, and answers have been given. One of the most popular ones is "apparent age": just as God created Adam as a mature adult, He created the Earth in a mature state. This is completely unsatisfactory. God created Adam as an adult so that he could function as one. However, differing levels of radioactive elements make no practical difference for the functioning of practically anything on the planet. Even if they did, it's hard to imagine a reason for them to be set in a coherent manner within an individual sample to converge on a specific age.
Probably the most common answer is, "it doesn't". Anyone making this argument is almost certainly under-informed, and in any case they're wrong. Unless they have access to significant amounts of data which the scientific community does not -- which is unlikely -- they simply haven't examined the situation in detail and thus cannot be expected to give a meaningful answer to the question. (I say "almost" certainly because of the existence of the Creationist leadership, who have no excuse for being unaware of the evidence. Many of their opponents simply say that they are lying, but I prefer to believe the best, so frankly I don't know quite what to make of them.)
I suppose another answer to the question would be that the ways of God are mysterious, and we cannot know why He did things this way. I agree, but look at where that leaves us. We have a consistent and coherent picture painted of the history of this planet, which seems to be the only one that stands up to rigorous examination. This cannot be an accident: either it is a true account of the way things actually happened, or it is an illusion that was intentionally created by God for purposes unknown, or both. What could He be trying to tell us? Is it a test, to see whether we cling to His Word in the face of strong evidence to the contrary?
Going along with this, is it conceivable that the consistency of the evidence might serve as a sign, from God, that we have to change our interpretation of the Bible? If not, that raises the interesting question: just what form could such a sign possibly take, if not this?
Clearly, the same sort of question applies to evolution and people's objections to it. However, I chose to frame it in terms of the age of the Earth for two main reasons. First, given what we know about evolution and how it proceeds, the Earth's antiquity is a logical prerequisite for evolution to be true. And second, I'm revealing my physics-centric bias once again. :)
I am genuinely curious to hear other answers to the question, or even to hear why the answers I listed were dismissed unfairly if you feel that they were.
Went bowling today, for the first time in ages. Things started out pretty grim; I had a whopping 57 even after 5 frames in game #2. Then came a strike, and a 9 -- but when I looked back, the last pin had toppled! I followed that close call with two more strikes, for my first two turkeys ever. I've been trying to do that ever since highschool! It was great to relax and get a bit of a break from school.
Of course, now it's back to the grind, back to the stat mech homework. I simply cannot get a handle on the Bromwich contour, and my ground state energy for the oscillators is double what I'd expect it to be. I hope I can finish the assignment tomorrow, and get my programming done! I'll be glad when this semester is over.
Just paid off the last of my student loans! Now I'm totally free from debt. It feels really, really nice. I'm going to start saving immediately so that Amy and I can attack our debts right away when we start our marriage.
Debt should not be an acceptable way of life! The financial irresponsibility of our culture as a whole really bothers me, and I hope I can always live up to that.
Personal
Cards
So I'm kind of new at this bridge thing, I admit it. I only know enough to know that it's the best card game ever, hands down. I decided to get my fix by playing online -- a bit of a crapshoot as far as partners go, but considering I don't exactly have the bidding down yet, I can't complain. My first partner was quite good and we played well together, and when he left I had high hopes for the next one. Then the unthinkable happened.
I found myself staring at a 19-HCP hand. In my hand alone I held over half the strength of the entire deck, which doesn't exactly happen every deal. And who should open the bidding before I even get a chance? My partner.
This happens approximately never.
A little mental math tells me it'd be a crime to quit before slam level, unless partner's opening was really scraping the bottom of the barrel. If memory serves, I responded to his 1C opening with 1D. When he rebid 1S, I was scratching my head for a way to show my strength without jumping to a game contract, which would be a signoff. (Remember, I'm new at this!) Then it hit me -- jump to 2NT!
At least, I think that's what happened. All I know for sure is that we agreed on a trump suit, and I jumped at the chance to bid a Blackwood 4NT to ask for aces. He responded 4D, showing one ace, and considering I had the other 3, I knew this might just be the big time! I asked for kings with an artificial 5NT, and got the shock of my life.
He passed.
So there I sat, an easy small slam, stuck in a 5NT contract. The highest risks for the lowest rewards. What happened next was pretty predictable: I yelled at partner, he hit the road, and I won all 13 tricks without breaking a sweat.
I really want to play some more! But considering I've come down with a nasty cold and can't think straight and can hardly breathe, I'd probably better just force myself to hit the sack.
It's been a real pain to be without a working laptop. Here's a brief history of my tale of woe, right up to the happy ending.
I was trying to get the new cedega version to work, and somehow I got the idea to run the python updater. I eventually was able to play Deus Ex on my laptop -- or, at least, to run it. It played at twice the normal speed, making it effectively impossible. Meanwhile, a staggeringly diverse array of essential programs (evolution, openoffice, ghostview, firefox, etc.) just started crashing. So Tuesday of exam period, I decided to wipe it & reinstall.
I thought I'd save myself some time (heh) and use genkernel for a default config. My reward was a non-working wireless card and the inability to start X-windows, among other annoyances. Attempts to "patch it up" with a regular kernel didn't really help, so I decided to wipe it and reinstall.
Well before I could get too far into it, Amy got to town, and you can guess who took priority between her and the computer! Not having time to finish up before we hit the road, I decided to wipe it and reinstall.
I never got home for more than a day at a time until it was practically New Year's, and we never stayed anywhere with wireless internet for me to get the installation done. When I finally got settled at home, it was a matter of getting the essentials up and running and sniping at individual problems, one at a time. It wasn't until yesterday that I finally got something genuinely new.
Apparently X does true transparency, and it looks very neat indeed. Be sure to check the transparency screenshots to see what I mean. Well... right now I only have one since my screenshot program is being finicky about actually picking up the transparency. But trust me, it's cool!
I still have to get a few more things done, like getting the USB ports running for digital cameras, or fixing the obnoxious vim scripting error that kills ftp browsing. And, not having a laptop prevented me from getting caught up on my email, not to mention the grant proposal deadline I missed! But at least I'm back in business, and ready for round 2 at CMU.
The SiteMy computer's been out of commission for a while, and I only just got everything reinstalled. Even now it's not really up to its old standards, and there's a lot I'm still working out.
Imagine my surprise when I visited my blog and found it overrun by spam! Luckily, they only got one blog entry, and it wasn't that bad, all things considered. They seriously misjudged their target audience if they thought hawking viagra on gpi.com was going to get them anywhere!
Unfortunately, I did have to disable anonymous comments. It was easy to do (thanks to my foresight in design!), but I really would have preferred not to force people to register just to tell me what they think of my blog entries. The good news is that user accounts are totally secure, in terms of spammers being unable to get your email addresses. The only way to get 'em is to look directly at the database! So, you're all safe.
Have a happy New Year! :)
I have mixed feelings about having given my final two recitations for the semester today. On the one hand, I'm relieved not to have to wake up before 7 in the morning just to get to school on time. On the other, I'm sure going to miss my kids! I ended up with two great groups this year with whom I could scarcely be happier. And my teaching today between morning and afternoon could scarcely be more different.
The morning section was subpar, to put it politely. I felt like I didn't enlighten them, and the fact that I forgot my textbook at school last night really showed through in my relative lack of preparation. It went alright, overall, but I didn't do nearly enough examples and I didn't explain what I taught particularly well.
The highlight of the morning section was definitely another transcendental experience. A rather bright student (whom I'll not name here) asked me a question about something I'd explained. While I was answering the question as best I could, I looked at him to find that he had fallen asleep while I was answering his own question. I asked him at the end whether the answer was satisfactory, and there was a noticeable pause before he jerked awake again and told me I had. Just as I was turning to write something else on the board, I heard his voice again.
"Um... could you repeat that last bit?"
I struggled mightily to suppress my knowing smile as I indulged his request. Fortunately, as a student, I know from experience that falling asleep does not imply a lack of interest. Still, I don't think that'll be topped any time soon!
By the time my afternoon section rolled around, I had definitely learned from my mistakes. I spoke clearly, gave good examples, and tied things up nicely at the end. As I began to hand back what homework remained, I received something I certainly never expected.
Applause.
Several of my students actually applauded my work as a TA as I finished. It was kind and affirming -- definitely an excellent start to my career as an educator! I know I still have a very long way to go, and have a lot of improving to do, both in terms of knowledge and technique. Still, it was a kinder compliment than I could have hoped for.
So we're down to two more assignments, period, for the semester, and one of them is due today. We're doing relativity in E&M, and it's been a real treat. For the first time, I feel like I'm getting a really solid foundation in this most beautiful of subjects, and the index gymnastics of Minkowski space tensor analysis is even starting to feel natural to me!
The first problem was to find the general Lorentz transformation for constant velocity in an arbitrary direction. I knew it had to reduce to the simple (quasi)block-diagonal form for velocity along one of the axes, and I was hoping for some kind of beautiful symmetry. My plan of attack hinged on realizing that regular rotations are Lorentz transformations, too!
So the idea is this: if the velocity vector makes a polar angle theta with the z-axis, and if its projection on the xy-plane makes an azimuthal angle phi with the x-axis, then we do a rotation about the z-axis by an angle phi, then rotate about the new y-axis by an angle theta. (The point of this is to line up the z-axis with the velocity vector.) Now we know how to do a Lorentz transformation along one of the axes; it's really easy! So we do that along our new z-axis, and then we make the inverse of the (composite) rotation we did to align our z-axis (which puts us back into the old coordinates).
Any symmetry I could have hoped for, I got. The first thing that jumped out at me was that when all was said and done, there was not the slightest clue in the final matrix that it was the z-axis I had chosen to align. (This is necessary for it to be correct, of course, but still very aesthetically pleasing!) Even better was when I subtracted off the identity matrix: the space-space components all had the same factor of (gamma - 1), and they all paired up perfectly: the xy-component had the product of the x- and y-projections of the velocity, same for the yz-component, the xx-component, etc. Simply beautiful!
The second problem was a more practical one: given that 2/3 of charged pions are observed to survive a distance 30 metres from a collision site (in a particle accelerator), and given the half-life of pions in their own rest frame, what is the energy of the pions in the collision? It wasn't particularly difficult, but it was a fun problem, particularly because if you use lab time instead of proper time, you'll come to the (erroneous) conclusion that they're zipping along faster than light. :)
The third problem was the hardest to do, but the easiest to explain to a general audience. Essentially, it's a more practical realization of the famous twin paradox. Usually, the twin paradox goes something like this: suppose of two twins on Earth, one leaves on a spaceship and travels near the speed of light for 20-odd years, and returns to Earth. How much time will have passed on Earth during that journey? (Answer: a lot more!) But if any reference frame is as good as any other, then the twin on the spaceship can surely claim to have been stationary while the Earth moved far away and then back, right? Well, the difference lies in acceleration: in order to get to the speed of light in the first place, the spaceship must accelerate, which is an effect that can be detected on the ship but not on Earth. Remember, not all reference frames are created equal, just all inertial reference frames.
But that's still a bit sketchy, becuase when the spaceship turns around, going from near the speed of light one way to near the speed of light the other way is a huge amount of acceleration, and our spacefaring twin has much bigger worries than a now-long-dead sibling. Jackson poses a more satisfying question: let the spaceship accelerate instead constantly, for 5 years, at a rate equal to the gravitational acceleration near the Earth's surface. (This will make the ride much more comfortable!) For the next 5 years it decelerates at the same rate, then turns around and does the same thing. 20 years total, from the spaceship's reference frame. How many years have passed on Earth in the intervening time?
Three hundred thirty-eight.
That's right, 338 years pass on Earth during that spaceship's trip. And believe me, that answer was not easy (for me) to come by! Consider this: the acceleration is constant in the spaceship's own reference frame. But it's speed in its own reference frame -- i.e., its speed with respect to itself -- is always zero by definition! Trying to figure out how it can be always increasing yet always zero is just one conceptual hurdle that had to be cleared. Really, all the difficulties stem from the fact that the velocity isn't constant: acceleration complicates things in special relativity.
I feel like I'm learning a lot in this class, and this semester overall. Now, time for exams and then Christmas break! (When I'll finally be able to respond to emails again... :P)
Good food, great discussion, and all of it free. It boggles the mind that more didn't attend!
We had a Pugwash meeting this evening on the topic of the ID/evolution debate, and what we as scientists can do to promote good science. Pugwash is named after Pugwash, Nova Scotia, where many eminent scientists first met in the middle of the last century to discuss the ethical implications of their work and their responsibilities to society at large.
There didn't actually seem to be any ID supporters in the crowd. The organizer tried to play Devil's advocate at first, but didn't have much to work with. We discussed the arguments for and against ID at first, then moved on to discussing why it doesn't belong in the science classroom and what we can do about it.
The main point that I took away from it was that more critical thinking skills are needed in schools in general, because good science is difficult enough to distinguish from bad science as it is. We can (and should) address the ID issue directly, but ultimately that's only a band-aid solution. It doesn't do any good for students to accept evolutionary theory just because teacher told them so: we must teach them how to think, and not what to think.
I sat next to a guy who was very strongly atheistic. Most of us didn't have a problem with ID being taught in, say, Philosophy class, but he was vigorously opposed to any form it might take, referring to it several times as a "dangerous idea". Funny, that's what fundamentalists usually say about atheism! Ultimately, I see the people who declare religion and science incompatible, no matter which they advocate, as flip sides of the same coin. As a religious person and a scientist, I strongly disagree with the both of 'em.
There was one person who was there from the beginning, and was relatively quiet compared to the rest of us. He made a comment about the compatibility of religion and science, and how they complement each other. Right on! He left soon after. I wish we would have heard more of what he had to say; there might have been some insights we missed out on.
Ah well. Now that I'm well fed (a bit too much so, perhaps) and home, I haven't really got any excuse not to prepare tomorrow's recitation.
