Light is definitely the single most important measure for scientists to study our universe. Since universe first became transparent 380,000 years after the Big Bang, thanks to its incredible properties, light has enabled humans to learn a great deal about universe as far as 45 billion light-year away from earth. Therefore, it is crazy to think about that even light has its own limitations, and our knowledge may not ever overcome these limitations. On the one hand, most of our universe is made up by mysterious dark matter that is only detectable through gravity. People were optimistic that implementation of LHC can decipher some secrets of dark matter. It has been 10 years since LHC’s installation, and there is no such discovery. We know it is there, but because it does not interact with light, we do not know any more about them. Can we ever get know dark matter? On the other hand, dark evergy is “bubbling” out of the empty space and accelerating space. There are parts of universe that are so far apart from us and moving ever faster away from us that there lights are never going to reach us. Thus, we will never be able to know these parts. Light has its limitations, and it seems that human’ knowledge stops at these limitations.