Hey guys, as part of a video project I'm doing we're often looking at constants, etc, and we've got a professor who LOVES big numbers and special constants... A couple of his videos so far are here: Big Numbers: http://www.youtube.com/watch?v=9T8Jk9w9Msw Fine Structure Constant: http://www.youtube.com/watch?v=WlSLIW0gZtk We've got plenty more films to make and I want to pick some brains about numbers that would make good videos (as long as they have bit of a physics bent and aren't purely mathematical, because our project is about physics and astronomy!) For more on the project as a whole see http://www.sixtysymbols.com/

I guess the lecturer explaining about how the fine structure constant is actually a variable dependent upon your energy scale would be a little confusing for the audience in general.... Symbols? K for Kelvin? q for charge? R for curvature (Ricci scalar, gets you into general relativity)? Numbers.... R (again) for the gas constant, gets you into fluids and PV/T stuff which is more accessible to school kids. \(l_{s}\), the string scale of string theory, approx \(10^{-35}\)m? I'll ask people in the office when they turn up for other suggestions.

Great suggestions.. A couple in the pipeline already (like Kelvin and charge) but I'll pass the others on to the team for future videos.

In particle physics the idea of a scale is more important than constants, for example the electroweak scale which is the typical energy of an EW interaction, or the Planck scale where quantum gravity effects become important. I find the limiting masses of stellar objects quite interesting and they are probably more relevant to astrophysics. For example the Chandrasekhar limit (try spelling that when you're drunk!) is the heaviest possible white dwarf and the Tolman-Oppenheimer-Volkoff limit is the heaviest possible neutron star.