Sunday, May 30, 2010

Karma and Carbon Monoxide

Earlier this spring I got into quite a heated debate on physicsforums.com about the nature of wave function collapse. In the course of that debate I leaned pretty heavily on the assumption that the basic chemistry of the photographic process involved a thermodynamically spontaneous transition from the undeveloped film to the exposed film. To be fair I never said I knew this to be true for a fact; I just said it seemed like a pretty good assumption, partly based on the fact that I never heard of anyone being able to "regenerate" used photographic film by, say for example, gently heating it to convert the exposed crystals back to their unexposed state.

I was ridiculed pretty soundly for trying to inject thermodynamics into the argument. Not knowing the chemistry, I kept pressing my opponents (who claimed some expertise in that field) to write out the reactions so we could evaluate it. Eventually it came out: at least in a simplified form, it appeared that we had to account for the reduction of silver bromide to elemental silver. Ignoring what happens to the bromine, we are nevertheless faced with a reaction enthalpy of 99 kJoules/mole in the positive direction: in other words, the reaction, far from being thermodynamically spontaneous, requires a significant input of energy. If we convert this to atomic terms, it comes to a near infrared "photon" for each atom of silver. It appeared that I was completely wrong.

And yet within a few days I had posted a counterargument which unexpectedly, and quite effectively rescued my argument from the ashes. It was a clever argument, backed up with sound mathematics; and one which I was uniquely predisposed to be able to make. Because thirty years previously, I had done a thermodynamic analysis of a chemical system in a completely different context which turned out to have the same essential features as the present case. I'm going to tell you about that now.

When I graduated from engineering in 1984, my first job was with Atomic Energy of Canada at their nuclear research station in Pinawa, Manitoba. You know that there are several different reactor designs out there, with the coolant system being one of the design variables. Some reactors are cooled with ordinary "light" water, and others with heavy water. The Pinawa reator was unique in being oil-cooled, which meant it ran at higher temperature with relatively lower coolant pressure.

Nevertheless one or the reactor's protective systems involved checking for cracks in the pressure tubes containing the coolant. This was done via a tube-within-a-tube geometry whereby the pressure tubes were surrounded by a containment tube full of CO2 gas, which was constantly purged and sampled at a monitoring station. Potential cracks in the pressure tubes could theoretically be detected by monitoring for trace hydrocarbon contamination in the CO2 purge gas.

The system seemed to work reasonably well for about twenty years, although it had a few quirks that no one worried to much about. Nevertheless, for one reason or another a decision had been made to upgrade and modernize the instrumentation, and as a new junior engineer I was given this relatively straightforward assignment.

That's where the story gets interesting. I'll continue with my next blogpost.

Wednesday, May 12, 2010

Do atoms behave as waves?

As you may recall, I was recently banned for life from the discussion group physicsforums.com. However, from time to time discussions take place in which I would like to put in my two cents worth. Today I am going to comment on the thread "Do atoms behave as waves?".

The most compelling evidence of atoms behaving as waves is the anomalous specific heat of diatomic gasses, which was known in the nineteenth century and caused great concern for people like Maxwell and Boltzmann. Here is the problem: the thermal energy of the typical diatomic gas such oxygen, nitrogen, or hydrogen is classically accounted for by counting the five modes: three translational and two rotational. (The third rotational mode contributes no energy because it is oriented along the axis of the dumbbell.) The theory works well in practise, except at low temperatures hydrogen begins to diverge from the expected value. It's as though the rotational modes stop contributing and only the translational modes remain in effect.

This is a clear instance of the wave nature of atoms. In order to properly drive the rotational modes, the dumbbell has to be cleanly struck by another atom. With classical billiard balls connected by pegs, this is no problem. But since atoms behave as waves, it's not so simple. At lower temperatures, the atoms move slower, so the wavelength gets longer. At a certain point, the wavelenght of the molecule is longer than the length of the dumbell, so it is impossible to strike one atom without also striking the other one as well. Therefore it is impossible to set the molecule in rotation to the full extent which is possible with simple billiard balls on pegs.

If you do the simple calculation of de Broglie wavelengths at the mean molecular speed and set it equal to bond length of the molecule, you get (within an order of magnitude) the well-known classical Wien formula for peak radiation frequency at a given temperature. It is interesting that you can get this result without recourse to the assumption that energy is quantized in lumps.

Tuesday, May 11, 2010

A Tale of Two Strikes


Some people might remember me from the 2004 (?) professor's strike at the University of Manitoba. I'm the guy who got arrested for taking over a physics class from the absent professor. A good story on its own, but not what I'm remembering right now about that strike.
I remember driving in to the campus and having to cross a picket line. The professors were milling about in the middle of the road while police stood by and made sure the cars waited until the profs were ready to let them through. Every group of cars had to pay its symbolic obeisance to the sanctity of the picket line.
I got up and started giving bloody hell to one of the officers on duty. "These people have no right to block traffic! Your job is to keep the streets clear, not to support the strikers!"
To be fair, it should be noted that these were campus police, not city police. Still, they wore uniforms and gave orders to civilians and called themselves police. I found it revolting that officers of the law would take sides in a strike.
Flash forwart to last weekend when I was on the other side of a work action. There was the company, the police, and the striker. I was the striker.
As for my union, I was alas a union of one. But surely this entitled me to no fewer civil rights than the powerful professor's union. Discrimination on the basis of union membership is surely prohibited by the human rights code. Shouldn't discrimination based of lack of union membership be just as wrong?
And if the laws protect the rights of people with good, high-paying jobs who think they deserve even more than they're getting, shouldn't it also protect the rights of low-life bottom-feeders like me with minimum wage jobs who are only asking to be paid the money they actually agreed to work for in the first place? If the professors are allowed to block traffic to ask for more money, shouldn't I be allowed to at least stand by the curb holding up a sign asking to be paid what I'm owed?
For what's about to come, let's assume for the sake of argument I was a terrible employee and the boss had every right to fire me. I can argue the opposite all I want and it doesn't make a hairs worth of difference, because the story I'm going to tell isn't about my dispute with the employer, it's about my treatment at the hands of the police. And as far as that is concerned, the facts of my dispute with the employer are irrelevant. So what if I was fired because I slept in the hayloft for four weeks instead of working, did I have less justice on my side than those professors with their six-figure salaries, their pensions and their sabbaticals, who struck in mid-term so as to hold the students hostage? But that's another argument. Suffice it to say that after numerous unsuccessful attempts to collect, I finally drove out to the hotel where I had been working and set up my sign beside the road. Accordian slung over my shoulders, I paced back and forth in front of the entrance. The question is: if the professors have the right to march in front of their place of employement carrying signs, what about me?

Within half an hour the Gimli RCMP was there, flashers blazing. An officer got out while his young female partner waited in the car. "What's going on here?" I pointed to my sign in reply: "Mike Bruno owes me four weeks wages AND WON'T PAY UP. The officer was unimpressed. "You're blocking traffic. You need to move your car."
I looked at my car. There was basically no shoulder on that stretch of road and little room before the precipice to the ditch. I pointed to my wheels about 18 inches inside the cement line. "Is it OK if I can get it off the pavement?"
This is where the run-around started. The officer wasn't about to give me the definition of a legal parking spot on the edge of the highway. To every location that I pointed at, he just said "you can't park there. Just get off the highway. Go find a side road somewhere and maybe you'll find a spot."
That was a specific as he was willing to get. He was no more cooperative on telling me what would be an acceptable placement for my sign, which had up til then been leaning on the back of my car. He basically just wanted me out of there and as much as told me so.
I got in my car and drove over to a nearby hiking trail and pulled into the entry area. "Is that OK?" All he would say is "if I get any complaints about it, you're getting towed". As to whose "complaints" would be sufficient to justify my eviction, he was silent. I leaned my sign on a hydro pole and he drove into the hotel compound with his young female partner.
Fifteen minutes later he was back. He pulled up and rolled down his window, asking me to come over. "How much money do they owe you?"
I didn't like where this was going. "Why do you want to know?" I didn't want to say "it's none of your business", even though that's what I was thinking.
He pressed me further. It finally came to the dreaded response. "Yes it is my business", he said, "because my business is keeping the peace and maybe I have a solution for your problem".
Up til then there had been no problem with "peace", and I was skeptical about his ability to negotiate a solution on my behalf, especially given his actions "on my behalf" up to this point. It seems that the hotel manager had given him a long story about what a bad employee I had been and how I should be glad to settle for a "reasonable" fraction of the hours I had put in for. Although I knew it would make me seem ungrateful, I simply had to tell the officer I wasn't interested in his mediation efforts. I turned to walk over to my sign.
He got out of the car and followed me. "Don't walk away when I'm talkiung to you. I'm trying to help you".
I turned back and said, "I'm sorry but I don't want your help. I want to do this my way." And then I walked away again.
"I told you not to walk away when I'm talking to you. Get back here right now". This was the man with the gun talking, and I can tell you it was very intimidating. Mustering my faltering resolve, I repeated: "I'm sorry but I'm not interested in talking to you any more".
"Well then I'm taking your sign". This was too much. "Take your hand off my sign. That's my property and you have no right to confiscate it". After a short tussle he changed tack. "All right, then I'm towing your car".
He had found nothing wrong with my parking spot fifteen minutes earlier, and now it was about to be towed. "Where do you want me to move it?"
"Why don't you find a paking lot?" he sneered. Obviously the only parking lot for miles around was off limits to me.
I got in my car and started driving, and almost immediately pulled into a private yard. The homeowner was outside and readily agreed to my offer of $5 for permission to park for the evening. "But I don't wan't your money. Park for free".
Elated that my problem had been so unexpectedly solved, I once again saddled up my accordian and headed back towards my picket station. But before I could leave the property, the RCMP car pulled into the driveway. To my shock and amazement, the officer went over to the homeowner and began trying to convince him to revoke my permission to park!
This was too much. Furious, I strode towards the officer. "Get the hell out of this property", I snarled. "I have a private arrangement with this homeowner and you have no right to interfere with it". At the very last word I approached within inches of his face and at that moment, he cried out jubilantly: "Assaulting an officer!" I found myself whipped around and thrust against the back of the cruiser. "You just make a big mistake," he gloated as the aghast homeowner watched in horror.
After locking me in the back of the cruiser, the officer planned one more treat for me. "Now", he said, "your'e car is getting towed". He went over to the homeowner but to the man's enormous credit, he would not be pressured by the police. "Let the man leave his car here. As long as he wants. And make sure it is locked before you drive away".
Denied this last bit of satisfaction, the officer contented himself with booking me for assault and throwing me in a cell with a metal toilet while he processed my paperwork. An hour later I was released, trudging on foot the three miles back to my picket.
Oddly enough, it felt pretty good. I had taken the worst they could give me and was still standing. My sign had been confiscated, but I still had two hunks of drywall in my car and a felt marker. After setting up my new signs, I pulled out the accordian and started playing.
I had one more surprise in store. Within half an hour a cruiser pulled up, this time with two different officers. "We've had complaints that you're blocking traffic."
Here we go again. "Is there anything wrong with my car?" No. (I hardly need mention that it was at that moment in a spot where the first officer had said he would have it towed.) "Is there anything wrong with my sign?" No. "Well in that case I've had just about enough of you people for tonight", I said, looking square at him. "If you see me breaking any laws, why don't you arrest me? Otherwise, get the hell out of my business!"
It felt pretty good watching them drive away, knowing that I had established my right to...well, to my rights as a citizen, as a human being. I'm not talking about so-called "human rights", which I despise. Those aren't rights. Rights aren't just for minority groups and trade unions and civil servants and lesbians...they're also for regular trailer trash white people like me. If I went to the human rights commission to complain about what the police did to me, they'd tell me to get lost. I'm not a protected group.
The rights I stood up for were the thing that actually makes freedom worthwhile. You just don't realize how fragile they are until you find yourself being stripped of them. And how easy it would have been for me to pack up and go home, to give up in the face of intimidation. But I stood my ground and faced them down. Because I knew that if I didn't make a stand then and there, that I might as well be living in Russia. Or North Korea. Or whatever country is the current poster boy for dictatorships.
The next day the police were back, with two more trumped-up citations for trespassing and blocking traffic. One hundred eleven dollars each. Not to mention the small matter of assaulting an officer. Never mind. I'll have my day in court. Today I am a free man.