a.
Boundary does not exist. The universe is expanding all the time, and human's
perception is infinite. Many unknown things become knowable with the help of
science and technology. Therefore, we are trying to improve our perception.
b. There is
a large amount of information in space, which is called "emptiness"
or "nothing" from the perspective of imperceptible sense. Without
feeling material time, macroscopically, everything visible is empty. In fact,
microcosmically it is everything. With particles changing all along, time is so
transient that we can hardly feel the time, so the void is the world of sense.
