Launch Report 2017-2 - LDRS-36
2 weeks ago
note that if you measure distance in seconds velocity becomes dimensionless. In particular you could put c = 1. All velocities would then be measured as fractions of c.
The idea is similar to lightseconds but not the same, since lightseconds is actually a unit of length, whereas here we have introduced a system of units in which any dimensionfull quantity can be expressed as any other one (if we also have h = G = 1). That is we can express mass as a certain multiple of an inverse meter, or second. So mass is really the same as a frequency. And of course in this system all our usual units correspond to particular dimensionfull quantities: one meter, one second, etc. And thus they can be expressed in terms of each other.