Key points are not available for this paper at this time.
ABSTRACT The Jeans criterion sets the foundation of our understanding of gravitational collapse. Jog studied the fragmentation of gas under external tides and derived a dispersion relation l^ = l ₉₄₀₍ₒ 1 (1 + ₀^{ / 4 G ₀) ^1/2} \, \,. She further concludes that the Jeans mass is m ₈₍₂₎ₑₑ₄₂ₓ^ =m ₉₄₀₍ₒ 1/ (1 + ₀^ / 4 G ₀) ^3/2. We clarify that due to the inhomogeneous nature of tides, this characteristic mass is incorrect. Under weak tides, the mass is m \, l₁ l₂ l₃, where the modifications to Jeans lengths along all three dimensions need to be considered; when the tide is strong enough, collapse can only occur once 1 or 2 dimensions. In the latter case, tides can stretch the gas, leading to the formation of filaments.
Guang-Xing Li (Wed,) studied this question.