Newtonian telescope secondary mirror. This design reduces the size and cost of the telescope with a shorter overall telescope tube length (with the corrector extending the focal length in a "telephoto" type layout) combined with a less costly spherical mirror. Commercially produced versions of this design have been noted to be optically compromised due to the difficulty of producing a correctly shaped sub-aperture corrector in a telescope targeted at the inexpensive end of the telescope market. Newtonian telescope The Newtonian telescope, also called the Newtonian reflector or just the Newtonian, is a type of reflecting telescope invented by the English scientist Sir
Derivations of the Lorentz transformations transformation matrices are consistent with group postulates: If then we get the Galilean-Newtonian kinematics with the Galilean transformation, where time is absolute, , and the relative velocity of two inertial frames is not limited. If , then we set formula_117 which becomes the invariant speed, the speed of light in vacuum. This yields and thus we get special relativity with Lorentz transformation where the speed of light is a finite universal constant determining the highest possible relative velocity between inertial frames. If the Galilean transformation is a good approximation to the Lorentz transformation. Only experiment can answer the question which