Electron density fluctuations (up to 2.5 Hz) in the solar wind have been studied, using the EFW experiment on the Cluster spacecraft, which measures density through measurements of the biased probe potentials relative to the spacecraft. The density fluctuation spectra obtained from the EFW probe potential variations are compared to earlier, OGO 5, measurements of ion density fluctuations and IS...

Quantum fluctuation expression of the baryon number for a subsystem consisting hot relativistic spin-$\frac{1}{2}$ particles are derived. These fluctuations seems to diverge in limit where system size goes zero. For broad range thermodynamic parameters numerical solutions obtained which might be helpful interpret heavy-ion experimental data.