In principle, the elements of space and time cannot be measured. Therefore, the following question How are reality and space-time related to each other? In this book, it is argued on the basis of many facts that reality is not embedded but projected onto space and time. We can never make statements about the actual reality outside (basic reality), but we can "only" form pictures of it. These are pictures of the same reality on different levels. From this point of view, the "hard" objects (matter) and the products of the mind are similar in character.
Einstein once said Space and Time are our modes of thinking. In other words, it's the relative position of the objects in the universe that gives space-time its existence. An empty space-time cannot exist. By the same token, if there's no observer, the reality of an object is under question. Wait a minute Morpheus! are you saying we live in a self-created "Dream World"? If these philosophical questions intrigue you, you may enjoy this book.