10 мая 2018 г. · The magnitude of the 4-velocity of every object through space time is c, except for photons, whose 4-velocity is undefined.

21 февр. 2020 г. · Four velocity is (γ,γv) ( γ , γ v ) . So in the reference frame in which an object is at rest, it's 4-velocity is entirely in the time dimension ...

19 июл. 2016 г. · The 4D velocity of a photon is concentrated in the 3 spatial dimensions. Is there an object that concentrates all its 4D speed in the time ...

21 авг. 2021 г. · Photons don't experience time, but they do travel at the speed of light. The reason the Four-velocity is undefined for a photon is that a Four- ...

6 июл. 2020 г. · The magnitude of the 4-velocity of every object through space time is c, except for photons, whose 4-velocity is undefined. Thus, is it true ...

3 мая 2016 г. · One is phase velocity (vp v p ) and other is group velocity (vg v g ). Phase velocity is the velocity at which the phase propagates. Group ...

25 мая 2015 г. · The 4-velocity of a particle moving at the speed of light isn't well-defined, but this is precisely because photon momentum is a null vector.

20 окт. 2016 г. · Four-velocity is the derivative of spacetime position with respect to proper time. That makes it a covariant representation of velocity whereas normal velocity ...

29 янв. 2016 г. · The velocity factor is defined as the ratio of the actual wave velocity in the medium to the speed of light in a vacuum, which is approximately ...

7 дек. 2022 г. · The magnitude of the 4-velocity of every object through space time is c, except for photons, whose 4-velocity is undefined. Thus, is it true ...