Just for those who are curious - A light year is the distance a light takes to travel in a year. Like a rock being thrown off a mountain, it started to roll together, increasing in mass. As mass increases, so does its gravitational attraction. Mass does not change. It is much more dense, with a smaller radius but same mass.
Gravitational force is higher.
The gravitational force is so high that it can now even bend light. This is the most brightest moment in a star's life. It is VERY dense. It is said there are infinite many stars in our galaxy. And our universe is infinite in size.