Relativity theory

The relativistic law for velocity addition
v = (v1+v2) / (1 + v1*v2 / c^2)

Length (Lorentz) contraction
l_r = l * saknis(1 - v^2 / c^2)

Time dilation due to relative velocity
Δ_t_r = Δ_t / saknis(1 - v^2 / c^2)

Relativistic mass
m = m_0 / saknis(1 - v^2 / c^2)

Relativistic momentum
p = m_0 * v / saknis(1 - v^2 / c^2)

Einstein's formula
E = m c^2

Einstein's formula
E = m_0 c^2 / saknis(1 - v^2 / c^2)

Total energy of the body
E = m_0 c^2 + m_0 v^2/2

Change of energy and mass
Δ_E =Δ_m * c^2

Lorentz transformation
x_r = (x - v t) / saknis(1 - v^2 /c^2)