H-I COLUMN DENSITY OSCILLATION IN INTERSTELLAR SPACE

The author proposes the possibility to observe the HI column density o scillation in small scales (similar to AU-scale) If such variance of t he column density were to be observed, he would suggest that the obser vational results show the existence of some type of waves in two-phase gas mixture. Such wave is known to be a void wave in the context of m ulti-phase fluid dynamics. If the variation of HI column density is re presentation of the void wave, we can also expect the HII density vari ations have anti-correlation to the HI density fluctuations, in the co ntext of classical two phase model of interstellar medium.