Tuesday, August 2, 2005
This morning, I arrived at the lab to see Matt sitting outside the door like yesterday; Dr. Noé hadn't arrived yet. So we sat outside again for a little while until some guy who had the key for some reason and happened to be walking buy noticed us, and let us in. Thanks some guy!
I then loaded up all my back journal entries with some difficulty. We then read about a Prof. quite unfortunately named Kock, and Matt decided to build an Op Amp circuit, and I pretty much just watched and learned. We also found a mysterious pair of glasses that everyone tried on, for some reason.
Dr. Noé arrived around 2:00-ish with some pizza for today's Tuesday Pizza Lunch!-- on Tuesday, even. In attendance: everyone from the Laser Center (Amol, Greg, Lindsey, Maaneli, Matt, Moon, Dr. Noé, Dr. Cohen, and myself) which pretty much transformed the special Tuesday Pizza Lunch! into just another lunch, with free pizza from Dr. Noé (thank you).
As far as discussing project ideas (today's planned topic), it was somewhat of an afterthought. Firstly, we discussed upcoming events in the Laser Center, specifically the Simons program tour of our lab on Thursday, at which all of us will have to make a presentation, and the REU final presentation on Friday, at which we will go to listen to Maaneli and Greg (and I suppose the other REU students) give presentations on their work. Dr. Noé also mentioned an EPA inspection of the lab that will be occuring next week, and also that next Friday, Aug. 12, is the last day of the Simons program, meaning that our formal summer experience here will be over. (We can still come in after then, however)
This news means more time distracted from working on a real "Intel project" as we will have to work instead on presenting some other work we've done to the Simons students. And as for that "Intel project"... I was hoping I'd have some more direction on after today's lunch, but I don't think that's the case. None of us really talked to each other about where we were going in terms of research, and as far as my particular project, the only thing said about it was "your project direction was the most uncertain of all", by Dr. Noé, and his recommendation was that I continue what I've been doing...
Anyway, after lunch we came back into the lab. A biology student (?) named Stephanie visited, and she and Moon really hit it off. While she toured the lab, Dr. Cohen sat down with me to discuss what kinds of projects I might work on. I told him some ideas I've had, but I guess neither of them were too good, since Dr. Cohen seemed to be pointing me towards a project suggestion of Dr. Noé's in which I will use the Michelson interferometer I've built to scan the phase plate Greg & Amol fashioned from a cover slip, in order to better describe, quantitatively, its shape. I feel, however, that such a project really should be some subset of their project, not the basis for my whole project. Then again, some project's better than no project.
I read about different LED manufacturerererers on the internet, and
then watched a superconductivity experiment by Maaneli in which a piece of
ceramic, when cooled with ample amounts of (very-cool) liquid nitrogen,
repels small magnets. I took several pictures that I'll post
tomorrow. Then I spent a couple of minutes looking disdainfully at the
remains of my Michelson Interferometer. Then I decided on what parts I'll
need to fix it. Then I checked out a note Stephanie left for Greg
(!). Then I talked with Maaneli about what the philosophy of anarchy
really is. Then I went home, at around 7:00. Today went better than
yesterday, in terms of productivity/learning, but I still have to turn it
up a couple of notches tomorrow.
Monday, August 1, 2005
Today I returned to the lab 'full time' again. I spent the early morning catching up on everyone's journals to see what had gone down when I was away, and then decided that my journal (which you may have noticed has not been very current) really ought to be updated too. So I decided to bite the bullet and get caught up to speed, which ended up consuming almost my entire day today, even though I had hoped to avoid that possibility.
I am now very afraid, however. As I look at the calendar, all that remains is this week and next week, and then the Simons program ends. Now, I know that I'll be coming back after that, but these are the only two weeks left of the 'Laser Center proper' left in which to develop a project, so I'll have to be very wary of spending my time unwisely. We'll have a Tuesday Pizza Lunch tomorrow, at which we'll discuss our projects again, so maybe I'll get some direction then.
Anyway, I think I have to finish writing that Optical Lever
Project report tomorrow... I hope it doesn't take all day too.
Friday, July 29, 2005
I came in briefly to catch up on what was going on in the lab, and do a
little reading, with the hope that I would get myself in a science mindset
again, and think about my project over the weekend. I read about focal
lengths, lenses, and tried to download OSLO, a lens-design program, but couldn't
since I don't have the proper permissions to on the lab computers. I'll
try to download the free version at home or something.
Thursday, July 28, 2005
I wasn't in the lab today at all.
Wednesday, July 27, 2005
I wasn't in the lab today at all.
Tuesday, July 26, 2005
I came in for another two hours this morning. I read some stuff on
architectural light piping and other 'non imaging optics' stuff on the internet,
mainly from a bunch of links Dr. Noé had given me, and left right before
the Tuesday Pizza Lunch, surprisingly on Tuesday, for the first
time ever this year.
Monday, July 25, 2005
Today starts my marching band's 'band camp', an intensive week of rehearsal in which we will learn and memorize the drill and music to our competitive show. Attendance is mandatory, so I won't be able to be in the lab much, except two hours each morning.
So I came in this morning, and Dr. Noé
asked me if I had completed my Optical Lever project write-up. After I
told him I hadn't, he had me start writing up the intro paragraph in front
of everyone, so that we could all be exposed to the complexities of writing a
scientific paper, and so that we would realize how every word in a paper is
carefully selected. The final paragraph we ended up with, after writing
committee-style, was very... graceless, I suppose? Perhaps unwieldy.
Matt was very nice and typed it all up for me on a webpage in his section of the
Laser Center site... http://laser.physics.sunysb.edu/~matt/nilus.html
Friday, July 22, 2005
Early this morning I was in one of the back rooms screwing my camera back together, when Moon came in. For some reason or another, we decided to play with the RadioShack Electronics Learning Lab, and we built a light-sensitive blinking diode setup. By the time we were done, it was time to go to the conference room, where Prof. Metcalf gave us a talk about Op Amps, following up on the discussion (and some confusion) of yesterday evening. I was encouraged by the fact that I could understand most of the mathematical concepts behind the physical concepts, which happens very infrequently. He also showed us some dissected diode lasers, miraculous devices which create an extremely intense light with a laser 1/2 a micrometer thick! Prof. Metcalf, when discussing light entering a new medium, said "When you enter into a material, the number of light waves, or wiggles, doesn't decrease. There's nobody in there eating wiggles!" which was pretty funny, especially considering his deadpan delivery.
We then went back to the lab, and Greg and Maaneli had to go to some REU lunch meeting. The rest of us decided to go to lunch too, and Dr. Noé piled us into the back of his 'vintage' Volvo station wagon and took us to a Thai restaurant in Blue Point (I think) which was interesting. We got all vegetarian stuff, so every dish (we shared everything amongst ourselves) seemed pretty much the same. I noticed a review from the Long Island Section of the New York Times by Joanne Starkey, whose dining guidance has introduced my family to many excellent restaurants in the past. She gave the place an average rating, but highly recommended the deserts, two of which we got... one being a deep fried banana, and the other some sort of deep fried ice cream in raspberry sauce. They were pretty good.
We braved a ride home in
super-hot weather, an extremely crowded back seat and a perilous trip to the gas
station (the guy next to us almost didn't shut off his engine before filling
up!) and made it back alive. Everyone pretty much left after that... I
stayed a little later, balanced my weight distribution 50/50 in the weird
rocking chair we have, and received some words of encouragement from
Maaneli in regards to my inability to grapple with math when dealing with
physics. I think I left around 6:00 or so.
Thursday, July 21, 2005
Today went really fast. I went into Dr. Noé's office early this morning to ask if I should throw out a several week old copy of The Times, and mentioned to him an article I had read in Tuesday's science section about the sky actually being purple. This precipitated a several-hour long conversation and collaborative web search in which we went off on tangents like "Whatever happened to Forest Mimms III, port wine stains, S.O.F.A.R., and New Zealand. Dr. Noé then copied the sites we visited down into an e-mail he sent as a joke to (or inspiration for) everyone else in the lab.
We then went to lunch at the SAC, where I got ripped off by paying $3 for an ice cream bar. We had a discussion on... guess... come on... right! Religion! What a surprise. I don't know if it was very productive, but over the course of the discussion, I realized how truly ideologically different Catholicism and Orthodoxy actually are.
On the way back, we met Dr. Noé, who encouraged us to use
had with him to look at the sky in observing the color saturation and Rayleigh
scattering. We came back to the lab, where Prof. Metcalf gave us our group
photos. and we all got together to discuss Op Amps, which Maaneli had been
working with Moon and Matt on, for use in his Sonoluminescence experiment, which
I didn't get to hear the end of since I had to leave, around 5.
Wednesday, July 20, 2005
More work on getting up to speed with my journal. Everyone else's journals are very text-based, with large blocks of text or math... I'd like to make mine somewhat more lively... so I've been putting a lot of images in to the entries, as you can see below. Making those images eats up a lot of time, and perhaps that's not a wise use of time. But that's what I was doing in the morning.
Dr. Noé showed me some websites on light
piping, and non-imaging optics, which excited me not only because it had
architectural applications, but because I just found the whole thing very cool,
somewhat more accessible to me with my limited math background, and a good
candidate for a field in which I could do my project. Dr. Noé
then took me to his office, where he showed me some super-reflective louvered
light fixture covers, which he installed in one of the labs in the deep belly of
the basement here. They're really clever devices which are placed over
built-in fixtures that restrict the dispersion of light, making for an eerie
effect: the light fixture seems black, while the room is still lit up as normal
(although supposedly with less glare) This is to prevent the
light fixtures of a room from being a distracting focal point when someone
enters (that is, the person's eyes are ordinarily drawn
to the bright lights on the ceiling when they enter, with these panels, that is
not the case) Dr. Noé also took me to his office to
show me some samples of the panels that he received from the company, so I could
inspect them up close. According to him,
Dr. Cohen came in around noon and was talking to Dr. Noé about various problems people had been encountering. We went to Jasmine for lunch, pretty late (except for Amol, who had already gone there to meet with his teacher) Moon asked everyone of they were religious, for the record, since we'd been having so many discussion on religion lately. Matt, Lindsey, and Greg are Catholic, I am Orthodox, Moon is nominally Protestant, and Dr. Cohen is Jewish (actually he didn't say if he's a practices Judaism or not). Maaneli and Amol aren't religious, while Dr. Noé is an APODist (his worship ritual consists of looking up the Astronomy Picture of the Day :p ). We discussed the concept of the Holy Trinity, the primacy of the Church over the Bible (since the Church actually developed it in around the 4th century) and debated the nature of Judaism as both ethnicity and religion. While Moon was caught in deep conversation about an equation with Dr. Noé, Greg and I stole her lunch tray and wallet. As we left, she chased Amol around, demanding he return it to her. Meanwhile, I had taped it up to the ceiling in the lab. I suppose she didn't imagine that I'd strike again. To the left is an image of Moon discovering her wallet, and on the right is an image of the same scene, except what it would look like if louvered panels were installed on the lights, to tie the whole thing into science. (Clever, I know)
came back to the lab, where Greg and Amol finally finished their new CJ (Caravelli
- Jain... their last names) Interferometer, and achieved a
nice-looking forked interference pattern, which caused Dr. Noé to
say "[expletive deleted]!" He also said "Sexy", in reference
to a picture he took of the phase shifter Greg and Amol fashioned from a plastic
cover slip... I took a picture of it too... it's shown to the left. He
then suggested projects to Moon and myself in which we analyze the amount of
bend at any given point on this cover slip. He explained that we could use
a matrix to do this, (or, in my case, I could use the
Michelson interferometer I built) and showed us an example in which
you set up a grid, with a given value at each edge of the square.
You then go around the internal cells and guess numbers based on those edge
values, and repeat your guesses over and over. I was perplexed by the
concept of 'guessing' to solve a math problem, but apparently, the math works
itself out eventually over the repeated cycles no matter what your guess is...
but the more accurate, the less time it takes. Moon and I solved one of
the matrices, and I left shortly thereafter, at 5:00.
Tuesday, July 19, 2005
Today we had a talk from Prof. Metcalf about clocks, which surprisingly dealt with a lot of quantum mechanics which went way over my head, unfortunately. I realize Prof. Metcalf is very enthusiastic about how students should ask questions, but to understand more than the very basics of his talk, I would've probably been there several hours asking questions. I did come away from the talk with a very different perspective on time in physics. I've understood that the concept of time is in many ways an invention of man, and is not very easily explained, but the fact that this is true not just in the popular sense of time, but also when dealing with time in a 'physics' context, is intriguing. I also now understand much more about atomic clocks, and how they work... I had known about them for some time, but had always had some strange idea of what they were. So even though I didn't understand almost all the math involved, I still think I came away with a lot of new knowledge. And I also came away with Moon's flip flops, which I taped to the front door of the lab, and to the top of one of the walls, after Greg had sneaked them away from her.
I spent much of the rest of the day
catching up on transcribing journal entries from my lab journal onto my laptop,
and then left at 5:00.
Monday, July 18, 2005
I came into the lab today and started working on getting caught up with my journal and writing my Optical Lever project report, both of which I had intended to complete before Dr. Noé returned from his vacation, but had been somewhat distracted from. I was hard at work when Dr. Noé came into the back room and noticed my new workspace, and my own computer, and suggested that in order to allow me to do more work on my laptop, and to ease the demand for the 3 Linux stations we had in the lab, that we purchase a wireless router for the Lab. He spoke to Amol about it, too, and I understand that they are selecting one.
He then rallied us together and, after he informed us of the happenings of his trip, asked us how our two days in the lab without him went. I told him about the improvements Dr. Cohen had made to my Michelson Interferometer, and about the things I had learned from him about interference. After the update session, Dr. Noé told us that we would be having a Tuesday Pizza Lunch today, Monday, July 18, 2005. The purpose would be to have a group discussion about our projects, which would yield some insight into what our interests and inclinations were, with the ultimate result being that we would come closer to knowing (or actually know) what our projects would be. How it actually turned out was the seven of us just told Prof. Metcalf about what we had been up to lately in the lab, and about our particular interests. I felt kind of let down, I suppose, since I was really hoping I'd come away from the meeting being significantly closer to figuring out a project. Perhaps it was just that my interests (which Dr. Noé told Prof. Metcalf were photography and architecture) don't meet very often in the optics field. To me, though, that's okay... I would be infinitely more happy doing a project not related to either of them, then to leave the Laser Center without a project at all (or worse, a flakey project)
There weren't any pizza contests after this meeting, however.
After that we came back to the lab, where I
worked on my interferometer and Optical Lever write-up until 5:00, when I
Sunday, July 17, 2005
I wasn't in the lab today, and I didn't do any reportable research, but I felt the need to write because I just saw STAR WARS Episode III for the first time and am really excited now!
Now I know what you're thinking... Star Wars Episode III? That's still in theaters? Well, yes: only 2 on Long Island are still playing it. But I just never got a chance to see it, since I was so busy between the laser center, marching band, church, and school (which is no longer a valid excuse in the summer time) So earlier this evening, I convinced my parents to take me to see it (I can't drive yet) and I'm glad I did. It wasn't exactly on a super-huge screen, but seeing it in the theater is such a different experience from watching it at home.
What a good movie, by the way! It was superbly done, I think, the best one yet. I liked how Lucas allowed himself to linger on the human aspect of the story much more than in the past... the scene in which and Anakin finally chooses to go down the path of darkness, (he is standing around as Mace Windu has gone to arrest Chancellor Palpatine) stands out in my mind in particular. It was excellently done; you could just feel the tension, the derision, the heart-wrenching and the nerve-wracking. The vistas of a Coruscant bathed in a dusky orange, and the quiet, droning music, all seemed much more sophisticated than any other cinematic techniques Lucas has used before, all making this scene stand out. But there were many scenes like this.
My only disappointments are a few. It seems like he cut out a lot of stuff; sometimes it felt like he was spending an inappropriate amount of time on a scene he really liked, and then ended up having to shorten a scene that was really critical to the story. Also, sometimes I don't think Lucas paid enough reverence to his own movie, making it seem almost too goofy like when...
I also think there'll be a Star Wars III.5, or there should be. There'll be 20 years between Episode III and IV, which is too long, I think, and is the longest span of any of the movies. Too much stuff will be happening in there that will go unexplored in movie form (I know there are books detailing Han and Chewie's meeting and exploits, etc.) But there are other themes Lucas introduced that no books have addressed, notably the concept of 'communing with the netherworld of the force' through Qui-Gon Jinn, as Yoda mentions too casually to Obi-Wan at the end of Ep.III.
And I want to know how the Rebel Alliance gets formed! Lucas left this totally unexplored, showing us very little, except Senator Bail Organa and his blockade runner, the Tantive IV (which is swallowed by an star destroyer in the opening sequences of Episode IV.) How does Jan Dodonna and Mon Mothma get involved? How does Leia get rise in politics?
I suppose some might say Lucas is leaving this to our imagination. If that was the case, why would he bother to make the prequel trilogy in the first place? He could've left that to our imaginations too, but his point was to explore that story in the cinematic medium. I guess I'm left thinking that, after Episode III, he did an honorable job, but not one that was thorough enough for my tastes.
Friday, July 15, 2005
Today was just as fun as yesterday. We played with liquid nitrogen, freezing everything from food trays to Bubble Tea tapioca balls, as well as using the vapors to help illuminate the Sagnac interferometer that Greg and Amol (or Amol and Greg?) built. We had several interesting discussions, such as one at lunch about the efficiency of vegetarianism (which I didn't really get involved in, since I feel inadequate to speak on the topic. I intellectually agree with the vegetarian's points about wasted resources and animal cruelty, but I lack the will and self-control to actually stop eating meat and dairy.) and one in the lab that started as a discussion on the nature of space and time, and then evolved into a discussion on the physical validation of religion (I avoided this discussion too, since I've had many debates about religion, and none of them end well. Besides, I think that those who are caught up in trying to produce physical evidence of God's existence are obsessed with the wrong aspect of religion)
Then people started heading out since it was a Friday,
and the dorms were closing. Greg wanted to show us a stand-up routine by
comedian Jim Gaffigan. The computer they were trying to watch it on has no
speakers, so he and Amol tried to build one (such is
the character of a student in the Laser Center... don't have an electronics
component most normal people would conclude would have to be bought for a lot of
money at some electronic store? who cares... we can make one ourselves!).
When that didn't work due to lack of adequate parts, we realized we could just
watch it on my laptop, which we did, and it was hilarious. After that, I
left around 6:00 ish.
pictures of fooling around with liquid nitrogen, from left to right: (1) when
poured on the floor on a puddle of water, the liquid nitrogen shoots small
globules of liquid (I don't know if it's water, or liquid nitrogen) out in all
directions. Try to touch it, and it disappears! (2) Amol shines a
green laser through the vapor rising from a closed container of water and liquid
nitrogen (3) half of a frozen rubber ball... it was later shattered, I think (4)
a three-second exposure of the Sagnac interferometer with vapors revealing the
laser beams. When the image is so red-saturated, it becomes pixilated, no
matter what the resolution... which is quite confusing.
Thursday, July 14, 2005
a picture of the main whiteboard in the Laser Center, which is usually plastered with complex physics equations
Ah... I came in today to a very different atmosphere. It was very much like a party... except one of those more sober parties... where everyone does work... Perhaps the unusual ambiance was thanks to DJ Moon, who was at the tables this morning, spinning an eclectic mix of rap, classical, and easy listening. As much as I don't care for two of those three genres, it was a welcome change from the Silence of the Labs (sic) that hangs over the lab each morning as we trickle in.
I wrote in my notebook for a while, took some pictures, then started writing up my Optical Lever Project at a workspace I had created for myself on a desk in the back room with my laptop. Dr. Cohen came in and started helping Greg and Maaneli with a photo detector quandary they were having.
Moon asked me about what happens when you shine a laser through a diffraction grating... in water... and I said I didn't know... so why don't we find out? I went and got a tank of water and in about 5 minutes we had an experiment going. Everyone (save Matt and Amol, who were at some Simons lunch/tour thingie) came in to check out the cool things the lasers were doing, but we quickly got frustrated with our inability to actually see the beams. I suggested that some milk would help. Greg said some lunch would help. All at once, we wound up in Jasmine. What a lunch. We had quite some fun discussing
Otherwise, Moon just said some really funny things. Good lunch.
We came back from lunch with a few precious drops of Greg's mango lassi in hand! Using it to cloud up the water, we began several neat experiments with green vs. red lasers. Above are 4 photos of what we did, from left to right, (1) two rainbow glasses produce several diffraction patterns on top of one another (2) reflection of a beam inside the water tank (3) the laser beam's several diffracted beams spread out from one another in the water (4) the higher-wavelength green laser is scattered more than the red laser. I also noticed that the green laser pointer looks a lot like a light saber when shined on a wall, and was then inspired to redo my Laser Center photo, as you can see from the front page.
After cleaning up my water tank, I did some photo editing and read The [New York] Times until it was time to leave for a rousing game of soccer. I did pretty crappy, but Moon did really well! She was all over the place and chasing people down like no body's business. I left the game early, around 8:00.
Wednesday, July 13, 2005
This morning I came in and worked on updating/streamlining this website, making all fonts and colors and such uniform throughout all the pages, fixing typos, and the like. The time went quickly when, all of a sudden, it was time for the first Tuesday Pizza Lunch ... on Wednesday!
During the Tuesday Pizza Lunch, Jan, a student from Germany working here at Stony Brook, introduced us to the world of X-Ray spectroscopy, while Moon and Greg had a [irreverent, though very funny] covert pizza eating contest. Greg, with 8 slices (some even with toppings) beat Moon, with her measly 6 plain slices. Dr. Noé left shortly thereafter for Ithaca, NY, to visit family, I believe.
After he left, we quickly descended into madness, the desire for a pull-up contest (long repressed by Dr. Noé's presence, I believe) went unrestrained, as, in truly strapping competitive fashion, Moon challenged the much larger Greg to a pull up contest. Moon managed a stunning 0 pull-ups, while Greg not only managed several, but also flung himself over the pull-up bar, over a nearby staircase banister, and onto a landing 12 feet above the ground, just to make his destruction of Moon clear to everyone around. Maaneli followed suit, for good measure. It was a good day for science.
We came back into the lab, looking for some research-penance, when we learned that NASA had decided to scrub the launch of Discovery (which was slated to occur today) due to a problem fuel sensor that, when malfunctioning, allows the shuttle's engines to blow themselves up. We were disappointed, but it was probably a smart move.
some discussion on this matter, Dr. Cohen, who had attended the
pizza lunch earlier, materialized in the lab, more specifically at my
interferometer, which he had improved to produce a smaller, clearer picture of
my interference pattern, through removing a lens I was using to focus light into
a microscope objective, and more importantly, turning the microscope objective
around so that it was taking in the somewhat-more-collimated light of the
interferometer in with the broad end, since in a microscope objective the broad
end typically deals with the collimated light, except in that case, it's sending
it out, to the eyepiece. Dr. Cohen also recalibrated the mirrors because
some of the light was hitting a mirror mount. Then I asked him about
straight line interference patterns, so we inserted another mirror in one arm,
to make both arms the same length, and thus even out the path lengths. I
then asked him about beating (or more correctly, I guess, 'modes') and
beating/modes in sound. We then went and played with the pendulum project,
and I got fairly confused with the amount of stuff I was learning rather
quickly. Dr. Cohen recommended that I read a chapter from Webb's
Elementary Optics book. I started, but then was distracted by something
else, perhaps Moon and Matt's random number generator or their percussion
machine, and ended up leaving, without having finished it, around 5:00.
Tuesday, July 12, 2005
We burned stuff in the morning! Using magnifying glasses to focus the sun's energy, we learned that as you collect light into a small area, it reaches the 50,000 watts per square inch needed to ignite something. I made Dr. Noé a smilie face. Science does have practical applications.
Then Amol and I worked on getting an interference pattern with the Michelson. I moved the top arm in to get a sharp interference pattern, and we realigned all the mirrors and lenses... but to no avail; we broke for lunch.
The aforementioned lunch was had in the SAC, for the first time in the upstairs eating area. I learned a lot about date rape and marijuana from some delightful packets we read over lunch. I also owe Amol $7 for buying me lunch... I mustn't forget to pay him back.
Realigning everything a second time, and introducing a new lens for converging light in on the microscope objective, I managed to get an interference pattern! Everyone had fun looking at it, but then Dr. Noé came in and told me about polarizing the light. A well-placed polarizer could restore an interference pattern that had become washed out by the interferometer's arms being different distances from the beam splitter, and being poorly aligned. So, I had to move the far arm back out to 28 cms from the beam splitter, to wash the pattern out, thus giving the polarizer something to do.
After everything was all set for
tomorrow's visit, I cleaned up the area a little and began reading a paper by
some team of scientists in Israel that everyone was talking about earlier in the
day, which had used cracked 'optical-quality Plexiglas' as a phase mask to
create special interference patterns, similar to what Dr. Noé and I had
been talking about on Friday. Then I called it a day around 5:00 and
headed to marching band.
Monday, July 11, 2005
I spent much of the morning going over the last week's notes. I also finished, and posted, my biography (I suppose I should call it my autobiography?) here on this website. At Dr. Noé's request, I removed my laser from the Michelson setup, and replaced it on the small breadboard, as to not prevent the possibility of a fiber optics/laser coupling experiment in the future. I then found a new laser to use in my Michelson, and set it up.
I worked on setting up the Michelson Interferometer (shown at left) for quite some time. Dr. Noé showed Amol and myself an optics demonstration which light diffracted around the edge of a microscope slide cover slip. We also looked at a microscope slide; in both cases, we rotated the slip/slide to observe the effects on the interference pattern. In both cases, one could see what I would liken to meteorological sundogs - spots (one above and one below the interference pattern) that move fast when far from the interference pattern, and slow when near.
noticed some periodic blurring and sharpening of the pattern; these were the
changes in the laser, according to Matt (who Dr. Noé called in when I noticed
this) Matt explained to me that the fringes of the traditional bulls-eye
pattern (the one my interferometer is producing is shown at left) are created by path length differences of light coming out of the beam splitter.
Now all I have to do is read up on laser phases and modes, and I'm set!
Friday, July 8, 2005
I spent the better part of the morning crunching over the previous days
notes and numbers. Yesterday's experiment, at a perfectly-aligned
45-degree angle of the reflecting mirror did not yield the approx.40 TPI
I was looking for. The data yielded the some bizarre answer like 14.5
TPI, and I simply chalked it up to my own lack of math skills and moved
on. I think that I have two variations on the equation
Dr. Noé created to compute the TPI count... I'll have to ask him
about that sometime tomorrow.
But when Dr. Cohen heard this, while he agreed, he felt that there was another problem... (one that I've come to understand is the cause of the problem Dr. Noé pointed out) that is that the experimentation was going on in two different planes:
The green triangle and the red triangle, conflict; there are two different planes, one in which the laser is bouncing off a mirror, and one in which I am moving the beam off the face of the laser onto a meter stick. I didn't realize it at the time, but this is not acceptable in optical experiments; for the purposes of getting good data, all adjustments should be made on the same plane (either left and right -or- up and down... not both) Somewhere along the line, Amol did some calculations, and said that while this sort of thing is undesirable, the data could be salvaged by multiplying each datum by the cosine of the angle I had the mirror rotated to (45 degrees) By multiplying my final TPI answers by cosine(45), we came extremely close to 36 TPI, to the point where the deviation could be written off as my own error in collecting data, or some other experimental error. Brilliant!
Given all this, however, at the counsel of Dr. Noé and Dr. Cohen, I decided to redo the experiment a fifth time, making sure to not deviate from the optical plane.
Somewhere along the line, we broke for lunch, after Dr. Cohen had left. We had a very long lunch at the SAC, mainly because we trapped inside by the torrential rains outside. Dr. Noé and I had a long talk about a whole panoply of things, from setting up a 4th workstation in the lab, to a cool lens-design program called OSLO, to a possible project idea of creating a 'phase mask', which form my currently minimal knowledge will retard portions of a light beam, creating forked interference patterns.
When we got back to the lab during a break in the rain, Dr. Cohen had also returned, and he helped me conduct Experiment No. 5, as well as calculate the data. The setup was the similar to a previous experiment, 'No. 3', in that I was bouncing a laser beam off a mirror, back to the right of the laser, making sure that all beams were moving around in the same horizontal plane.
The results of this experiment yielded 33.8 TPI. This is not 36 TPI, nor is it truly 'close'. In trying to explain this new discrepancy, Dr. Cohen mentioned that he had observed my method for quarter-turning the knob as inaccurate; I was never sure of any position except for the '12:00' position, or rather, the full rotations. Going back and excluding all data except those collected at the full rotations of the knob, we realized that my measurement for Δm, the movement of the beam on the meter stick, was actually 2.825 cms, not the 2.99 I had determined by including my inaccurate quarter-turn data, too.
When we readjusted Δm in the equation, the outcome was 35.8 TPI... extremely close to 36 TPI. Success!
The mystery solved, the project complete, I began dismantled my set up and began building a Michelson interferometer, and embarked on my next project... and then left for home at around 8:00 PM.
If the above did not make sense, I am working
on a more detailed, more organized write-up of my experiments, which I will post
in a separate section of this website.
Thursday, July 7, 2005
This morning started out with screws. I spent much time last night and
this morning trying to find a chart of English screw sizes. Now I know,
in failing to to find a good chart, and visiting several other websites,
the difference between wood screws, machine screws, and bolts, as well as
the only two camps of standardized screw
sizes: UNC&UNF/SAE/English, and ISO/Metric. Anyway, after I failed my
mission, Dr. Noé found exactly what I was looking for in 60 seconds
on Google. This is why he is a teacher, and I am not. But that chart
still didn't have all the screw types, so I might make my own, gathering
all the sizes in one place, in one chart, in a
forthcoming section of this site for all the world to benefit from.
Wednesday, July 6, 2005
I started the day off transcribing notes form yesterday's lecture by
Prof. Metcalf, as well as the data from yesterday's experiment, in my
Tuesday, July 5, 2005
We began the new week with a lecture from Prof. Metcalf on matrices and
the commutative property. We discussed something that are commutative,
but some that are not: elements in a lens, transformations of an object,
and the placement of polarizing filters, to name a few.
Later on, Amol began writing a matrix that would represent the
polarizing effect of any polarizer, when theta was substituted for the
angle of the polarizer. After quite some time, with a little help from
Maaneli, he finally arrived at one. Satisfied, we all went to the
SAC for lunch, leaving Dr. Noé and Lindsey to mull over
their own version of the solution.
Monday, July 4, 2005
We had the day off. Happy Deep Impact / Independence Day!
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