Quantum Physex

I've been trying to solidify my understanding of quantum theory and linear algebra for almost a month now and I've finally gotten it! I was reading Quantum Physics by Gasiorowicz this morning when I read this line: "...we drew attention to the fact that the complete set of eigenfunctions was similar to a set of unit vectors in a vector space, and the expansion theorem was similar to the expansion of an arbitrary vector in terms of unit vectors that span the vector space."

I almost shat a brick. Seriously.

Finally! Once again, months of my physics education clicked in an instant. This statement by itself isn't very complicated, but it's contents are fundamental and deeply profound when things like the uncertainty principle are examined. The uncertainty principle (one version of it, anyway) states that you can't simultaneously know with absolute precision both the position and momentum of a particle. The first reaction to these experimental woes was that somehow the measurement techniques were flawed. When examined from this mathematical perspective, the uncertainty is inherently a part of the system! Now, with just this alone not much can be said. The uncertainty principle could just be a consequence of the model we've constructed, however, there are many other factors involved that have a much more solid physics basis.

All in all, when things like this click in my head I feel as if I've unlocked some new door to the universe. I couldn't focus on much of anything for about half an hour... so profound!

Lab work is going well. I got my Radiological Worker II training, which means I can now work in High Radiation and High Contamination areas. I don't expect to have to do that often, but if I do I know how to put on the crazy radiation suit to do it.

Part of our helium-jet system has a recirculation cart that controls the flow of helium, provides pressure measurements at key points, and also recirculates the helium creating a closed system. Since this cart was shipped in from Canada and hasn't been used in 15 years, we need to test it for leaks. This involves pumping the system to a vacuum and using a leak detector.

The leak detector is essentially a mass spectrometer tuned specifically for helium. You use the detector to pump your system down and use a helium gas cylinder to spray tiny amounts of helium gas over parts you think may be leaking. If any helium gets through, it gets sucked into the detector and it makes this awful beeping noise. I found a pretty huge leak, which is good. However, I can't isolate it from the rest of the system. This is a problem because with such a big leak, I can't get the vacuum to the level I need it at. Because of this, the background noise of the detector can't get low enough for me to detect smaller, albeit problematic, leaks. I'm probably going to have to wait for JJ to get back from India before I can go any further.

I'm also working on a calculation concerning our Argon flow. We have our system set up such that Argon flows out of the flowmeter at a specific rate through about a meter of tubing and into the ion source chamber. Now, the whole reason that things flow is due to pressure differences. Mass flows from areas of high pressure to low pressure. This means that if my Argon is coming out of my flowmeter at a specific rate, but travels through some tubing, there is an additional pressure differential between the flowmeter and the ion source chamber. There is a formula that relates the pressure drop between to reservoirs and the associated flow rate. What I need to figure out is how our output flow rate will be affected by traveling through this tubing via the pressure differential. My problem has been with converting between different types of flow.

The flow that I know isn't actually a mass flow. It's in unites of Joule/second, but it's written as pressure*volume/second. What I need for the formula is volumetric flow rate: volume/second. So I've got to look at a lot of factors when converting between the two, like the relationship between density and pressure/temperature. Since I'm not expecting a huge pressure drop between the flowmeter and the chamber (since our flow rate is so small), I'm going to assume the Argon is at the pressure of the chamber and go from there. Now I just need to find a pressure/density relationship.

I'll be Atlanta inbound about 4 hours from now. Another chapter of my fraternity is visiting, so I'm stoked to see those guys. There's also a party at CoLab on Saturday that I'm really looking forward to. All in all, an exciting weekend awaits!