Physicists like to name things after their discoverers. Sometimes if there's a unit of measurement that doesn't have someone's name attached to it, they'll grab the name of somebody who worked in that field and use it. Let's take a look at some units, first a few examples not named after people:
Length - meter
Mass - kilogram
Time - second
There's a couple more slightly obscure units not named after people, but most units are named after somebody. Sometimes repeatedly:
Temperature - Kelvin, Celsius
Current - Ampere
Electric Potential - Volt (the guy's name was Volta, but close enough)
Magnetic Field - Tesla, Gauss
Energy - Joule
Force - Newton
Inductance - Henry
Capacitance - Farad
Resistance - Ohm
Magnetic Flux - Weber
Pressure - Pascal
Power - Watt
Electric Charge - Coulomb
And so on and so forth. Pretty much everything major has a named unit, and most of them are named after someone. Less fundamental concepts often don't have their own separate name, but are built up from the other named units. Electric field is measured in Volts per meter, for instance.
What I think is a bit odd is that physics has never come up with a named unit for momentum. Momentum is about as fundamental as it gets in modern physics, so you'd think they'd name it after someone. Momentum is mass times velocity, so its units are kg m/s. This also happens to be the same as force times time, which would be equivalent to a Newton-second. That's often what's used to describe impulse, which is just the change in momentum. Rockets are often characterized by this quantity.
I feel this is kind of a sad state of affairs. Momentum should have its own name. Newton would be the obvious person to name it after, but his name is already the unit for force. I'd suggest Hamilton, for the guy who developed mechanics around generalized momentum, but his name is already taken by the Hamiltonian. How about the Galileo, which we could call the Gal for short? Nope, it's taken. I can't think of anything satisfactory. Perhaps it should just be left as it is, but it does feel like a bit of an obvious gap.
Two quick links as well:
First, Carl Brannen has an excellent post on physics and the financial crisis. "All humans are basically a bunch of beanie-baby buying bozos and will drive any market, free or government-controlled, into wild oscillations." Yep. I also see the bailout we got because it was "a necessary evil" has not stopped the Dow from hitting a 5-year low. Color me unsurprised.
And here's James Lileks on his trip to Disney's Hollywood Studios. James is (like me) a tremendous fan of retro-futurism, and Hollywood Studios is so streamlined as to border on the raygun gothic. I still prefer the straight Art Deco of the 30s, but this is almost as good.
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Make the unit of momentum the noether (lowercase for units, uppercase for names and unit abbreviations), mischieviously covering linear (from homogeneous vacuum) and angular (from isotropic vacuum) momentum. As a bonus, it will have everybody debating an umlaut. That is more fun than a mole of photons with twice "e before i".
the Heisenberg! Of course, you could never then be quite sure of the momentum...
I've been using Boltzmanns to measure entropy for at least a decade now. In a lot of statistical physics temperature looks like the derived quantity, and a system of Boltzmanns and Joules per Boltzmann makes more sense than Joules per Kelvin and Kelvins.
Heh. I'm going to link this post to my high school class website, as we're just studying momentum now. I keep telling them that it could one day be named for them, if they get famous enough.
Have you already answered the question as to why the symbol for momentum is p? I mean, it obviously can't be m, but...
I vote we name it after the theoretical physicist Alan Sokal, for "transgressing the boundaries" of le woo postmodernisme in the most exciting, entertaining, and unanswerable way.
(Pardon my French; I'm not French.)
And sometimes they just fail completely when naming things. Reference the emu for instance.
There really is only one possible choice!!!
"After the collision the billiard ball had momentum of 18.3 Aristotles".
Seem to remember there was a proposal a few years back to name it after Descartes. I think he was the first to seriously study the quantity mv.
The answer for the symbol (p) is closely tied to the lack of a unit name. After all, some of the names listed above are fairly new. It wasn't that long ago (sixty years) that force was in dynes and energy in ergs. Forty years ago, Halliday and Resnick were compelled to have an entire appendix devoted to conversion from MKS to the (then) more widely used cgs "gaussian" system of units.
Using "p" for momentum only goes back to the development of theoretical mechanics in the late 19th century, the q and p we all know and love. [There it seems to have been used only because q is next to r in the alphabet, hence a good choice for a generalized position, and p is next to q.] It had to work its way down from advanced textbooks to introductory ones. I suspect, but cannot prove, that it came into intro physics with the 1950s reform of physics education, to introduce that symbol and concept at an earlier point in the curriculum. I know that p was not used for momentum in a well used (a 1939 edition in its 23rd printing by 1947) intro physics textbook. All you saw was "mv" in the *very* short section devoted to the topic. Ditto for some older textbooks I own. Unlike today's pedagogy, which emphasizes the insight of Hamilton and Lagrange, momentum did not even rate a chapter in that mid-century book!
As for unit names, I thought the best choice would have been the newton. After all, momentum is what Newton was talking about most of the time when discussing "inertia" and defining the second law.
So name it the Dangerfield, since it doesn't get enough respect.