FTL Neutrinos and the Fine Structure Constant

Hi again,

It looks like the fine structure constant ain't so constant.  The fine structure constant is a pure number of about 1/137 that was thought to be a fundamental constant.  It's the ratio between the energy needed to overcome electrostatic repulsion between two electrons a distance d apart and the energy of a photon of wavelength 2 pi d.  Chemistry is all about the energies involving electrons and light, so the fine structure constant pops up a lot in quite a few fields.  The fine structure constant depends on the charge of the electron, the speed of light in a vacuum and Plank's constant, so as long as all these are in fact constant, their ratio will be a universal.

This past Hallowe'en, however, Physical Review Letters published a highly-confirmed yet still extremely controversial paper showing that in old galaxies, the fine structure constant is higher in older galaxies.  There are only three possible causes; one of them must be true:

1. The charge on the electron is larger in older galaxies
2. The speed of light is smaller in older galaxies
3. Plank's constant is smaller in older galaxies.

None of these choices are all that appetizing, but #2 is consistent with the idea of my previous post that there's a particle field we haven't found yet that's slowing down photons a bit. As a nice bonus, the order of magnitude of the change in the fine structure constant observed is pretty close to the order of magnitude of the factor of the photon slowdown seen in the OPERA experiment.

These thoughts are still just tantalizing ideas, and there probably isn't a connection.  Drop me a line if you have ideas about this!

Cheers,

LeDopore

FTL Neutrino Predictions

I thought I'd jot down my ideas about the recent OPERA superluminal neutrinos at CERN.  In case you hadn't heard, the experiment found neutrinos that (as far as they can tell) move slightly faster than the speed of light.

If correct, this is a big deal, since "faster than light" in one reference frame means "back in time" in another.  Being able to send information back in time would lead to implausible, crazy new technology.

My best guess as to what's going on is that there’s a systematic error in OPERA we haven’t found yet.
My second best guess: light actually travels a little slower than c, at least around Earth. This could be due to interaction with some unknown particle cloud that’s consistently uniform and has a refractive index of 1.0002.

No, this isn’t the aether, and this isn’t experimentally contradicted by the fact that the speed of light doesn’t change as the Earth changes velocity through this field. Just as the speed of light through a moving glass rod isn’t greater or smaller than through a still glass rod (neglecting dispersion, which comes into play as the Doppler-shifted frequency of light causes n to change slightly), moving through this weakly-interacting particle background doesn’t change the observed velocity of light, unless the medium is dispersive. A good assumption would be the medium isn't noticeably dispersive: whatever transitions the light interacts with are of such high energy that photons we generate all look about the same, and dispersion isn’t measurable.

Heck, the medium could even be dark matter. This hypothesis solves a bunch of problems, like why the neutrinos from the 1987A supernova were coincident with (and not before) the photons. Under this hypothesis, the photons traveling though deep interstellar space would not be slowed by the presumably rarefied dark matter there.

Like I said, my money’s still on the possibility that there’s a systematic experimental error at OPERA. However, I find the idea of a vacuum/dark matter refractive index a lot more palatable than particles that violate causality. I haven’t yet heard a good reason to discredit this idea, so I thought I’d post it.
Background: I have an honours physics undergrad degree, but I’m now a neuroscientist. None of my colleagues are capable of evaluating this idea; if it’s rubbish please don’t hesitate to point out why.

News Flash: Rocks Too Deadly for Schoolkids?

Greetings, daredevils.

I just happened upon a great Forbes article about the insane lengths the Consumer Product Safety Commission goes to keep dangerous toys like plain old rocks out of the hands of schoolchildren. I'd write more, but in some ways res ipsi locutor, and I have to get to work too.

Via BoingBoing.

Give Parents a Chance: Part 1: diaper diatribe

Greetings, potential p1 generation.

It's been a long time since I posted to this blog. My life's been irrevocably improved by a nine-month-old daughter, and I've changed cities as well. I bet you might have thought I was gone for good, but here I am, back with another cold, hard numerical look at our decisions.

Today, I'm going to write a post I wish I'd read a few months before coming a dad; this may evolve into a short series.

Over-educated parents get weird about a whole lot of things and one of them is diapers. It's practically taboo for a Ph.D.-toting couple like us to use throw-away diapers that will sit in a landfill for eternity. We've bowed to social pressure and bought a g-diaper system, complete with multiple reusable covers (that need a lot of laundering nonetheless) and flushable inserts.

The joke's on us, however, since cloth diapers on the whole are not any more environmentally friendly than disposables. Laundering cloth diapers in soap and hot water takes as much energy and releases as many chemicals into the environment as having disposable diapers.

The three big advantages of disposable over cloth are:

1. Cost (disposables are about half as expensive)
2. Baby's skin (disposables these days can keep 'em dry through the night)
3. Time (it's much faster to change a disposable diaper than a cloth one, and when you're only getting 4 hours of sleep a night for the first three months, even an extra 5 minutes 8 times a day is really appreciated)

Item 3 is so important that I'll come out and declare that even if 1 and 2 were not true, it would probably still be best for the family to use disposables overall. When you're taking care of a newborn, you need time. Other things like budgets and environmental concerns - especially the matter of a couple of cubic meters of solid waste (all the diapers that the baby will make over their lifetime) - can and should be put on a back burner. Be with your kid, not your laundry service.

In conclusion, let me absolve any prospective parent out there (I can do this now that I'm officially ordained - another story) of any disposable-related guilt. Disposables are awesome technology - use 'em with a clear conscience.

Getting a D in Health

Greetings, indoor, computer-reader.

The Sunbathing Ape

It's natural for us to feel drawn to amazing photographs of sun-soaked landscapes. We humans evolved as mostly-naked, outdoorsy folks in sunny Africa. Although the cultures (and to some degree the genes) of migrating peoples have done what they can to adapt to more polar environments, if you dig at all deep into our biology you'll see we still aren't fine-tuned to live indoor, boreal lives.

One of the biologically unmet expectations humans in the USA and Canada experience is low sun exposure, leading to Vitamin D deficiency. This article in the Globe and Mail suggests that Canadians typically have about one third of optimal concentrations of vitamin D in their bloodstream.

What's D Good For?

Until recently, it was thought that the major effect of vitamin D deficiency was rickets. Since (last time I checked) rickets wasn't an endemic problem to North Americans, vitamin D was seen as being a non-issue; the mandated additions of D and A to dairy products seemed to be sufficient to keep bone formation normal in children.

However, vitamin D has more functions than merely the regulation of bone density. It's also an important chemical precursor to a lot of important cellular signaling mechanisms: not having sufficient vitamin D is the equivalent of trying to run a government when there's a shortage of notepads to write on.

D and Cancer Rates

One of the worst consequences of screwing up chemical messages is to impede natural anti-cancer cellular mechanisms. Does our D-prived culture result in fact in increased cancer rates? The only way to know for sure is with a double-blind experiment where groups are given vitamin D and placebos at random, and to track prevalence of cancers in the two groups. That's exactly what this study did, and what they found is almost unbelievable. Giving 1.5g supplemental Calcium with 1100 IU per day (about 3 liters of milk worth, but the study used pills) decreased cancer rates by 77% after one year.

Great moons of Neptune! That's a huge decrease! The cautious part of me finds it hard to believe that one factor could be responsible for over half of cancers, and to be fair the study tracked only 1200 women over 4 years, and thus wasn't able to notice enough cases of cancer to have really tight confidence intervals: the range of cancer decreases still consistent with the study is 91%-40% 19 times out of 20. Still, I've started feeding vitamin D to my wife as well as taking it, if not daily, than at least often.

Public Health Consequences

Suppose the study's numbers bear up, and that about half of cancers could be prevented by 1100 IU of vitamin D per day. Would it be a good policy for health insurers (or friendly socialist governments like Canada's) to simply hand out vitamin D supplements? It looks like the cost of vitamin D is pretty much nothing: this bottle of 250 pills (almost a year's supply) with 1000 IU of vitamin D is only $10. On the flipside, the annual cancer rate in the US is 1 in 200. If that could be halved by the D supplement, and if treatment costs on average $40 000, that's an expected savings of $100 per year. Pay one dollar into prevention, get 10 out in unneeded treatment. (Oh, then there's the whole increase in lifespan and quality of life issue too.)

Last Word

I suppose the cautious policy approach would be to conduct a larger study to figure out where within the wide confidence interval the truth lies. However, I'm inclined to start ramping up vitamin D production and consumption programs, maybe even with heavy subsidy by governments, HMOs or otherwise. Let's get a D in health.

Editing Miranda

Greetings, lawmakers.

When was the last time democracy had a makeover? Arguably, there hasn't been a big change to the way Americans govern themselves for 200 years. Well, except maybe allowing black people to vote in 1969 and women in 1920; OK maybe there have been some 20th-century improvements in terms of who can vote. However, in almost every one of today's democracies, the only governmental venue where the electorate at large expresses their views is at the polling station.

The Checkbox Menace

Yes or no questions can distort your position. Don't believe me? Try:

Does your wife know you have a mistress?

Elections so far allow only really coarse-grained opinions to pass from the people to the law. Politicians don't have a monopoly on good policy ideas, ergo there are some great ideas floating around which will never see the light of day as long as votes are the only way to influence laws.

Until now, this restriction of opinions has been necessary to keep procedures streamlined: there's been no way of having an intelligent exchange of opinions with 200 million voters. Until now?

Kiwi Wiki

That's right, the New Zealand government has opened up a wiki site where they let you draft the law. Its power so far is only advisory (I think that's wise, at least for now), but it allows good ideas and intelligent debate to percolate up from the people without the government doing a thing (apart from setting up MediaWiki or some such).

I'll be interested to see what comes of the New Zealand experiment. Does anyone below care to register their predictions as to if this will be fabulous or a flop?

Keep on wikin',

LeDopore

Rail Blues

Greetings, Takers of the A-train,

Last night I went to a show in the big city. As you know, I don't own a car, so I took a subway car back, and noticed how very odd it was that about 100 rich patrons waited with me for over 20 minutes for a train. (My metropolitan area has notoriously infrequent trains, especially at night.) It got me wondering: how crazy is it (financially) to run trains infrequently at night?

Extra Costs

It's easy to say "Let's just run trains every minute," but the whole reason why public transit systems work is that many people going the same way can use just one vehicle and driver. Let's figure out the cost of splitting one infrequent but long subway trains into two shorter trains.

If the run lasts two hours and the driver costs $40/hour (including overhead, training, etc.) the personnel expense is $80. The necessary force (hence electricity cost) of pushing an additional train front through the air can be calculated using:

F = .5 A D p v^2,

where A is the area of the train front, D is a drag coefficient (usually about .25 for aerodynamic shapes), p is the density of the medium and v is the speed. Using A D = 4 m^2, p = 2kg/m^3, v = 20 m/s, electricity costs $.15/kWh and the distance traveled is 100 km, we see the extra energy costs is a measly $7. Let's round up and say an extra $100 would be needed to run an extra train.

Extra Benefits

So, how much shorter a commute would there be if an extra train came? The trains come every 24 minutes, and by the time a train came last night there were over 100 people waiting at my station and over 100 at the next station (the two busiest, mind you); let's lowball the estimate and say 250 people would be able to catch a train on average 6 minutes sooner if train frequency were doubled. Doubling train frequency means 25 commuter hours would have been saved at a cost of $100 to the system: $.40 per passenger or $4/hour of passenger time saved.

However, increasing service might increase ridership, so it's possible that the extra train would (at least partially) pay for itself. Increasing ridership eases burdens on parking and roads too; public transit is overall a good bargain.

Summary

It's time commuters got vocal about being willing to pay a fair amount for their time that gets wasted by sluggish schedules. I wish we'd get a consistent metric of how much our time is worth, and use it to make policy decisions. Check out my post on machine wages for equivalent cost-time comparisons; this concept may evolve into a wiki page soon.

Keep on track!

LeDopore