1\ Prerequisite
We can assume that a virtual information-carrier is outside an universe when its (spatial or temporal) extension is beyond the smallest possible (spatial and temporal) curvability of this containing universe. Thus, the smallest possible Thing in our universe U (i.e. the quantum of things) is maybe the light:
-> Smallest Curvability of U = Smallest Physical Extension wihtin U
-> Schwarzschild radius = Compton Wavelength
2\ Schwarzschild radius
On the other side of the Schwarzschild radius, the (potential or cinetic) energy of any Thing doesn't suffice anymore for that poor Thing to come back into our world. Then, this Thing is prisoner in a kind of anti-black-hole:
-> -GMm/r + mc² = -GMm/infinite + 0
-> r = GM/c²
3\ Compton Wavelength
Nothing (no photons?) cand be quicked quicker as:
-> λ(c) = hc/Mc²
4\ Planck Radius
The Planck Radius is, as well, a quantum of radius; because it is the smallest possible length measurement:
-> r = λ(c)
-> r = GM/c² = hc/Mc²
Therefore with:
Speed of Light in Vacuum…… c = 3 E8 m/s
Planck Constant…………………… h = 6.62 E-34 J.s
Gravitation Constant…………… G = 6.67 E-11 Nm²/kg²
We get the following granularity of our universe:
Time…… t = r/c = 1.35 E-43 s
Mass………M = sqr (hc/G) = 5.46 E-8 Kg
Radius……r = sqr ( Gh/c³) = 4.047 E-35 m