I have recently been reading an introductory book on tensor analysis and came upon an unfamiliar notation. The book is pretty good at introducing new notation but this 'came out of left field'. After referring to a vector v (boldface) it suddenly uses it in an equation as a bold face v with a bold overbar. Maybe it's just a typo or perhaps it's some notation I should be familiar with, although that would be strange as I am reasonably familiar with vector analysis. I don't have access to the book at the moment but the equation seemed to make sense if you ignore the overbar. I'm wondering though if there is some common notational convention I'm missing.
I have seen v-bar used to mean a velocity vector. Edit: For example: http://en.wikipedia.org/wiki/Rendezvous_pitch_maneuver#Maneuver_description
As you can tell from the replies, it's a bit ambiguous without context. I've seen it used to denote different coordinates (though that's usually a squigly bar) and also for conjugation, I wouldn't say either is common though, it's usually always defined if used.
The overbar may be intended to signify 3-vector while the bold signifies 4-vector. It might also signify unit-vector. You can figure out the meaning from the context.
Yes! The light bulb just came on. Unit vector. Thanks to all especially Tach. Please Register or Log in to view the hidden image!
Yeah, I am familiar with a hat signifying a unit vector. Also by a vector divided by its absolute magnitude. But I don't recall ever seeing it as an overbar. Odd. Anyway, the equation makes a lot more sense now.