In physics, ultrarelativistic is said of a particle when its speed is very close to the speed of light c, such that its total energy E2 = m2c4 + p2c2 is almost completely due to its momentum (), and thus can be approximated by E = pc. Physics is the science of Nature. ...
In general, the ultrarelativistic limit of an expression is the resulting simplified expression when is assumed. Or, similarly, when the Lorentz factor is quite high (). It has been suggested that Lorentz term be merged into this article or section. ...
Goodness of the approximation
The relative error of the ultrarelativistic limit for a speed v = 0.95c is around 10%, and for v = 0.99c it is of just 2%. In the mathematical subfield of numerical analysis the approximation error in some data is the difference between the exact value and the value used. ...
Other limits
The opposite case is a so-called classical particle, where its speed is way below c and so its energy can be approximated by .
), and thus can be approximated by 
).
.
Feeds |
Contact