...that I like living in Oxford:

Being a small city, it is large enough so that there are always plenty of things to do, yet it is small enough that I can randomly run into people I know on the street with reasonable frequency.

For instance, walking down the Banbury Road to work this morning, I ran into one of the bell ringers from the St. Giles group. She was outside of the vet's office buying a 5kg bag of cat food. The same vet where we buy over-priced[*] 10kg bags of cat food every seven weeks for our little furry ones. At other times, in town or on a bus, I have run into my ex-landlady[**], my ex-landlady's mother, my boss, my colleagues, other Oxford Physics people, other ringers from St. Giles, ringers from OUSCR -- you get the idea. Heck, in December, I ran into a random guy and his kid that [livejournal.com profile] cheshcat and I had eaten lunch with in October at the One World Fair. And it turned out that we had seen his kid perform the night before in the carol service at Christ Church Cathedral.

In the past, I have lived in a big city (New York), a rural area (around Hampshire College), and far too many suburbs. Other than the 'burbs, which I dislike, all of these types have their appeal to me. But I've never lived in a small city before -- Oxford has a population of about 150,000 -- and I find that this can also be quite charming.


Anyway, here is a quick rundown of what I have been up to this week:

Work
Took apart the electronics for the Kelvinox-400 cryostat and rebuilt them in a way that made sense. Mainly to eliminate things like ground loops and 50 Hz noise. Don't know what a ground loop is? Consider yourself lucky! As the old saying goes: Love my job -- hate the ground loops! Also used the radioactive cobalt-60 source to calibrate one of the thermometers via nuclear magnetic orientation thermometry. The method is very closely related to the experiments done to prove parity non-conservation in the 1950s[***], which won my quantum mechanics professor -- C.N. Yang -- his Nobel Prize. Now that the cryostat can reliably be made cold, we are getting its electronics and thermometers nicely sorted so that we can move on the next stage in this work. Which, unfortunately, will only be discussed via private e-mail and personal discussions -- not in the public space of this journal.

Extra-Curricular (i.e., evenings)
Monday: Already wrote about. Swam laps and then watched Babylon 5 with [livejournal.com profile] cheshcat

Tuesday: [livejournal.com profile] cheshcat and I met [livejournal.com profile] wolfpeach at the pub[****] for a relaxed evening out. It is nice to have another friend in Oxford, and one who falls into the poly, gamer, geek mould, too! Good food, good conversation, good company, and games! Played a couple of rounds of Lord of the Fries while a bad open mic blared in the background.

Wednesday: Went back to the Ferry Sports Centre and swam another mile. I can't easily express how good it feels to be back in the water. Ever have something that you miss terribly... but don't realize how badly you missed it until you have it again? It's like that.

Thursday: Had a lesson on handbells at St. Giles and then rang tower bells with the usual practice. I have actually reached the point where I can ring the 1-2 part for a plain course of Plain Bob Minor on handbells. Which, while not nearly as interesting as ringing tower bells, is some nice progress.

Tomorrow, Friday, [livejournal.com profile] cheshcat and I have tickets to see Playhouse Creatures at the Old Fire Station theatre... and Saturday evening we are having C&M come over to hang out and play games. At least that's the plan. As we all know, the best laid plans...

[*] Cat food in this country costs three to four times what it does in the States. If it weren't a violation of Her Majesty's Customs laws, I would bring twenty pound bags back from the US each time go to the Event Horizon.
[**] And also a current friend. Known in this journal as EO-W.
[***] Don't worry if this makes no sense to you. Seeing as how I've provided no explanation, are odds that you don't understand what this means or else, if you do, that you are a particle physicist.
[****] "The pub" meaning, in this context, Far From The Madding Crowd. Oxford has, for all practical purposes, an infinite number of pubs. In my year here, I have been to nine: The Bear, The Mitre, Eagle & Child, Far From The Madding Crowd, The King's Arms, The Gardiner's Arms (North Parade), The Gardiner's Arms (vegetarian version), The Royal Oak, and the Dew Drop Inn.



From: [identity profile] gyades.livejournal.com

slight correction


The method is very closely related to the experiments done to prove parity non-conservation in the 1950s[***], which won my quantum mechanics professor -- C.N. Yang -- his Nobel Prize.

From this, it sounds a little like Yang did the experiments. But, as I'm sure you know, that honor belongs to C.S. Wu. Yang 's contribution (along with T.D. Lee) was to suggest that parity wasn't conserved in the first place.

On a related note, at an anniversary celebration of the whole deal, I saw Lee stand up at a talk Yang was giving on the subject and start --not quite-- shouting at him. So indeed there is a feud between them.

On another related note: Lederman almost concurrently discovered parity violation in muon decays. But whereas Wu's experiment was a careful and painstaking one, Leon's was an over-the-weekend modification of his grad student's thesis experiment. I can't do the story justice, but you should read "The God Particle," at some point.

OK, enough random geekery.

From: [identity profile] anarchist-nomad.livejournal.com

Re: slight correction


I do indeed know that Madame Wu carried out the experiments that proved Lee and Yang were correct. I'm sure you also have heard the stories about what a disaster Yang proved to be in the lab... resulting in his career being firmly directed towards theory (where, as we all know, he was a fantastic success). I don't know if those stories are urban legends or not, but...

I had heard of the feud between Lee & Yang. Have never met Lee, though. He's not on the list of Nobel Laureates that I know. Where was this talk?

As for Leon: Yeesh! That guy is just too damn smart! You know, he and Mike Turner share an office on the sixth floor of the high rise, just down the hall from where my old office at the lab was. Not that either of them were really ever in it...

From: [identity profile] gyades.livejournal.com

Re: slight correction


I'm sure you also have heard the stories about what a disaster Yang proved to be in the lab.

I have indeed. And if they're urban legends, then Yang himself has some blame for spreading them. According to him, when he was a grad student people used to say: "where there's a bang, there is Yang!"

He's not on the list of Nobel Laureates that I know.
Y'know, such a statement could be construed as pretentious! I just think it's cool to be able to say that at all.

Where was this talk?
I believe it was APS '06 in Dallas. Of course, the reason for the feud remains obscure to me. Lee seemed to be claiming that Yang didn't really deserve credit for the work, but I couldn't tell if that was the cause of the feud or a viewpoint that had been distorted by it. Yang pretty much ignored the outburst, which was probably the best way to handle the situation.

From: [identity profile] anarchist-nomad.livejournal.com

Re: slight correction


Y'know, such a statement could be construed as pretentious! I just think it's cool to be able to say that at all.

Heh. Yeah, I guess it is. Cool, I mean. Though potentially pretentious is also possible, I suppose. I find it slightly humbling to have spent time with Nobel Laureates, actually.

In all fairness, my list is not that long. I have been taught by C.N. Yang (as have you). I have collaborated with Koshiba-sensei (on Super-K) and with Jim Cronin (on Auger). I have met Frank Wilczek, Leon Lederman, and Ray Davis. I have listened to seminars and/or colloquia from Carlo Rubbia, Riccardo Giacconi, Doug Osheroff, and Bill Phillips. And I have written to George Smoot. Probably the only one of these people who would still recognize my face and have a name to attach to it is Jim Cronin. Though perhaps Prof. Yang still remembers the time that I came to his quantum mechanics class wearing a Batman mask and a cloak. Hey -- it was Halloween!

From: [identity profile] anarchist-nomad.livejournal.com


*grin* Always happy to provide entertainment!

To put this in a little bit of context, the conference that [livejournal.com profile] gyades is talking about happened last year, in 2006. T.D. Lee and C.N. Yang (and Madame Wu) shared the Nobel Prize in 1957. So this feud apparently goes waaaaaay back!

From: [identity profile] acelightning.livejournal.com


I'm only barely following the physics-geekery (although my husband, who graduated from Stony Brook with a BS in physics in 1972, once took a class taught by Yang, and has also told me stories about Madame Wu). But I do know what havoc a ground loop can wreak. And fixing the ground loop ought to get rid of most of the 50-Hz hum. (You don't know how automatic it is for me to type "60-Hz hum"!). My advice: ground everything. With electronics, at least, there's no such thing as "too grounded" ;-)

From: [identity profile] anarchist-nomad.livejournal.com

Ground loops


Removing ground loops can take a lot of work. Such was needed at CRESST several months ago and now JI & I have been doing it for the Kelvinox electronics here in Oxford. We aren't doing too badly right now. When we began, the full range amplitude of the 50 Hz noise was 8 volts. Now it is down to about 33 mV. To remove it completely -- or even to go any lower than we already have -- I strongly suspect that we would need to construct a Faraday cage around the system. Which isn't going to happen. Although, for CRESST, the cryostat, detectors, and front end electronics are indeed all within a Faraday cage with a single ground connection. All mains power and external signals are then passed through filters as they enter the cage.

Regarding the idea of being "too grounded", it is possible. In that multiple connections to ground are the cause of ground loops (as I am sure you know). When we began, the cryostat insert was grounded in multiple locations. At this point, the K-400 is only grounded in two spots. Would that we could remove one of them for a single ground! But, alas, that is simply not possible without a major effort...

From: [identity profile] acelightning.livejournal.com

Re: Ground loops


EIGHT VOLTS of hum?!?! Dear gods, was the equipment hooked up in series with an electric kettle or something? (Come to think of it, why isn't the entire lab inside a Faraday cage, if the one at CRESST is?)

What I meant by "ground everything" was to establish a "ground bus", a heavy copper wire (or even rod) with a good solid earth ground, and then ground all the equipment to this as directly as possible. Most of the radio stations I've worked at were built this way, especially the AM studios located right next to the transmitter towers. AM transmitters require "ground radials" (each one about the length of the tower it was attached to!) leading out in all directions, buried a few feet down. That's why so many of New York's AM stations have their transmitters in the New Jersey meadowlands - the swampy land there provides exceptionally good grounding. (Gods, I love low-frequency RF!) Not only did the system grounding improve transmission and reduce hum and noise in the audio lines, it also protected everything from lightning ;-)
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