Rational Galaxy Structure and its Disturbance
  Why is there little dust in elliptical galaxies? Firstly, the universe is rational and the rationality is the proportional density distribution in any independent galaxy. Proportion means that the density distribution of stars is orderly. For example, there are four giants standing in array. Their heights are A, B, C, D, respectively, and A, B stand in the first row from left to right, C, D in the second row from left to right. Proportion requires that A divided by C be equal to B divided by D. Rational structures are smooth 2- (or 3-) dimensional structures, which are either circularly (spherically) symmetric with respect to the center point, or bilaterally symmetric. Secondly, spiral galaxy arms are linearly shaped, which are neither circularly symmetric nor bilaterally symmetric. Therefore, arms are not rational structures. Arm patterns exist only in spiral galaxies and they are weak compared with the main disk structure. Therefore, the presence of arm structure is the disturbance to the rational structure. Because arm patterns exist only in spiral galaxies and only spiral galaxies present dust, I come to the critical answer to the above question: any disturbance to rational structure produces cosmic dust. From now on we call the disturbance to rational structure the cosmic impulse. Therefore, the universe is originated not only rationally but also impulsively. 
Jin He