Tell Them!

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The Utility Of Physics

Excellent points about the general question of why physics is important and should be funded.

Even in areas in which it is difficult to argue for the application and usefulness to the public, we can bring out the argument that it is difficult know the future applications of such knowledge. The history of physics is littered with many such examples, including quantum mechanics. The early development of quantum mechanics had almost no emphasis on the usefulness and application. If we only want to fund work that had such clear utility, then we would have missed out on the development of quantum mechanics.

This, in particular, given the recent (and incredibly myopic) push to limit research funding to areas with commercial or national security applications.

Playing Small Ball

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Why Do Small Science?

Chad breaks down the advantages and disadvantages of the user facility model, and why AMO physics is better off without it. I think he hit the high points, like the “economy of scale” advantage of having staff technicians to handle the equipment that isn’t part of your particular experiment, and disadvantages like

[I]f your small experiment that plans to use the particle beam from some accelerator or reactor breaks just before your scheduled beam time, well, try again in six months or a year, assuming they give you another block of time.

This was a constant fear when I was at TRIUMF, and something always broke just before we had beam time, requiring long hours to fix right before we went into “experiment running 24/7” mode, and had to surrender time on at least one occasion. We also tried to be ready to grab someone else’s beam time in case of problems, when the right target was in the beamline, and I have a vague recollection of doing that, as well.

Letting the Air Out, Thank Goodness

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I was gearing up for a rant about how the sequester, and in particular the furloughs, were sucking all the air from the room, but it was just announced that they will stop at six days, which means just one more week of this nonsense. So that kills the worst part of my rant, thank goodness.

The lesson of the first four-and-a-half-weeks is that scheduling time, especially with more than two people, becomes incredibly more difficult when you lose a day per week if your furlough days aren’t synched up. Any interaction where you need information from someone else, or vice-versa, becomes strained; there is no quick turnaround when key people are absent on random days, and you have your own work you are trying to get done. Work in the lab has slowed considerably because that’s one of the variables, while bureaucratic nonsense seems to be a constant, and when you reduce hours, the constants don’t seem to shrink. This was not a 20% reduction of useful work output — it was more than that. These are probably some of the reasons academic researchers work the long hours: they can, because they are on salary, and the research part of the job is where the extra hours are spent, after teaching and doing all of the bureaucratic overhead.

The people up on top of the food chain, to their credit, have been insistent that nobody sneak in unpaid overtime to compensate. It was recognized that a furlough meant that work would not get done. It seems to me that many were irked by the political narrative that there’s all this fat and bloat in the military, so that the sequester will have no effect on operations, because the fat would be cut. Well, guess again. It’s more that the DoD part of government actually is big-boned, and what looks like fat is more of a system bloat that needs to be restructured, which doesn’t happen simply by starvation.

Here’s a rough example of what I mean: spending money has a huge overhead of paperwork. One of the reasons for this is that government employees need to be good stewards of the taxpayer dollars they get, so there are a whole bunch of rules to follow to make sure money is not mishandled. But all of the paperwork and regulations make the process inefficient, which wastes taxpayer dollars. However, nobody is willing to streamline the process, because eventually there will be some misuse of funds (or even just something that has an appearance of impropriety), and too many members of congress, and the general population, will go absolutely apeshit over the revelation. So we spend many dollars in order to safeguard fewer dollars. That’s a systemic problem, and not one that can be solved simply by reducing budget.

But my creeping malaise seems to be somewhat better now that the end of furloughs is in sight, even though the larger sequester problem still exists. I had joined a colleague in meaningless protest by not shaving (anywhere). He started while I was on vacation, so I got a late start, but even the shorter duration doesn’t change the fact that I had one of the worst beards grown by anyone of drinking age. Glad to be rid of the non-goatee portion of it.

Science Pudding

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Bad Astronomy: Global Warming Denial Is Science-Proof

Antiscience cranks, such as global warming deniers, never seem to pass up an opportunity to equivocate if it helps them look good (to the choir, at least, since the dishonest arguments are transparent to people who know what they’re looking for). If a scientist uses a lay definition, hold him/her to the scientific one, and vice-versa.

Phil is right — science doesn’t deal in proof; that’s the realm of math (or alcohol). Science deals in evidence, and in confirming models to a high degree of confidence. If a scientist says that we’ve proven something to be so, they are using a lay definition, meaning that we have very strong evidence.

Like gravity. You can’t definitively “prove” gravity but you wouldn’t want to bet against it.

I hold [the rock] over my foot. I know that our understanding of gravity is not 100% perfect, that Newton’s laws are an approximation, and that Einstein’s rules are more accurate. I can even argue over proof versus evidence versus reasonable doubt, but in the end, once that rock is falling, the science is good enough to know I should move my foot.

Atomic Bullying

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Over at Uncertain Principles, Chad has started up a series on cold-atom physics. I do a lot of the very same things since I also work with cold atoms; we’re well past the time in the history of this area of physics where simply getting atoms cold is the research. The variety in the research these days is in what you do with the atoms once they’re cold (f’rinstance, I have ways of making them tock)

Here are the first three posts

Tools of the Cold-Atom Trade: Introduction

Tools of the Cold-Atom Trade: Light Scattering Forces and Slow Atomic Beams

Tools of the Cold-Atom Trade: Optical Molasses

But here’s the thing: photons are really cheap. A red laser pointer that you can get for next to nothing at your local office supply store will put out 1,000,000,000,000,000 photons per second.

I love the line “photons are cheap”.

I recall a time when I was showing off our atom trap at TRIUMF and discussing how we detect the atoms so that we know the trap is working (as opposed to the nuclear experiment we were doing), and there was a bit of a communication difficulty, because the nuclear physicist wasn’t used to thinking in terms of getting anything but one particle per atom to detect. But an alkali atom can scatter millions of photons per second (with the transition we were using, if you’re near resonance), which is the complementary part to “photons are cheap” that is important. I can’t think of a catchy description that I’d use, though. (Maybe “atoms are gregarious”?)

That Which is Not Forbidden is Mandated

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That line, (or something like it), borrowed from literature by Murray Gell-Mann, refers to particle physics. Unless a reaction is not allowed (i.e. it violates some conservation law), it will have some probability of occurring, even if the amplitude is small. And you would have to include it in your “sum over all paths” calculations of interactions.

Well, it appears to apply to science journalism as well. Wrenching a statement out of context and misinterpreting it is apparently not forbidden, so a story will appear that just gets it wrong, as so often happens and happened again. Via ZapperZ, I see that there’s a story about the upper mass limit of photons article I mentioned recently, that takes a disappointing tack:

Photons May Emit Faster-Than-Light Particles, Physicists Suggest

Oh, good grief no. That was not “suggested” at all, and certainly wasn’t the point of the paper.

Here Comes Trouble

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The Trouble With Teleportation

For a long time, physicists assumed quantum teleportation wasn’t possible. In order to teleport an object, like our pig lizard, we must scan it to obtain precise information about its atomic structure. However, the more accurately an object is scanned, the more it is disturbed by the process of being scanned. We can’t measure a particle without altering it in some way, never mind every single subatomic particle that makes up a full-sized pig lizard. So how could we extract all the information we would need to create an exact copy in another location via teleportation?

In 1993, an IBM physicist named Charles Bennett and his colleagues figured out a way to work around this fundamental limitation using quantum entanglement

Kudos to Jennifer for mentioning that quantum teleportation transmits information (rather than objects), and doing it several times.

Unfortunately, there is one omission.

Ah, but there is a catch: The original object must be destroyed in the process. When B scans A, that interaction alters the latter’s properties. A no longer exists in the exact same state as it did. C is now the only particle in that original state.

No! The information about the original object must be destroyed. When, in the experiments she mentions, teleportation succeeded between clouds of atomic vapor, the atoms themselves were not destroyed. That would have certain implications, making a million or so atoms just go poof — it would violate a bunch of conservation laws, not the least of which is conservation of energy. The atoms did not simply disappear and then appear in the adjacent space — this is not Star Trek. There were two clouds, and the information was teleported from one to the other.