text: A 2010 paper reported that a new calculation of one of these quantities differs by 5.0 standard deviations from CODATA's value.
full_question: A 2010 paper reported that a new calculation of one of these quantities differs by 5.0 standard deviations from CODATA's value. That quantity is the "charge" type of this property for the proton. The Stokes-Einstein equation for the diffusion constant has this value and viscosity in the denominator. Another of these quantities is equal to h-bar divided by electron mass, speed of light, and fine structure constant and is named for Bohr. This value is inversely proportional to centripetal acceleration, and is crossed with force to give torque. A type of this property is defined as the distance at which line cannot escape a black hole and is named for Schwarzschild. For 10 points, name this property that is multiplied by 2 pi to give the circumference of a circle.
first_sentence: A 2010 paper reported that a new calculation of one of these quantities differs by 5.0 standard deviations from CODATA's value.
raw_answer: radius [or charge radius; or Bohr radius; or Schwarzschild radius]