The Gupta Empire, although short-lived, did manage to consolidate most of northern India and present day Eastern Pakistan into a united empire. After the collapse of the Gupta Empire, India was not re-united for several hundred years. The time of the Gupta Empire is referred to as the "Golden Age of India" because of numerous artistic, religious, and architectural developments. A number of scholars were active in this period which resulted in the advancement of science and knowledge. An extensive trade network was also established. Among its accomplishments were the concept of zero and the idea of a heliocentric solar system. The game of Chess is said to have originated during the Gupta Empire.There is some belief that during this empire a number of religious works explaining the doctrines of Buddhism, Hinduism and Jainism were created. The Gupta Empire was thus the first Empire that could be positively identified as uniquely Indian. Its contributions are still part of much of modern Indian culture.