CREATE TABLE table_19989 ("Condition/Parameter" TEXT, "Coordinate velocity v dx/dt in units of c" TEXT, "Velocity angle \\u03b7 in i-radians" TEXT, "Proper velocity w dx/d\\u03c4 in units of c" TEXT, "Lorentz factor \\u03b3 dt/d\\u03c4 = E/mc 2" TEXT)

If the velocity angle is ln[(1 + 5)/2] 0.481, what is the condition/parameter?
SELECT "Condition/Parameter" FROM table_19989 WHERE "Velocity angle \u03b7 in i-radians" = 'ln[(1 + √5)/2] ≅ 0.481'
SELECT "Condition/Parameter" FROM "table_19989" WHERE "Velocity angle \u03b7 in i-radians" = 'ln[(1 + √5)/2] ≅ 0.481'