Our awareness that time stretches back long before we were born, and will continue to stretch into the future long after we're gone, lies at the heart of our humanity. Without this sense we couldn't learn from the past, and wouldn't plan for the future. But where did we come from, and where are we going in time? Every culture mythologises time and attempts to answer the ultimate questions: was there a beginning? And will there be an end?
In the 17th century an Irish bishop used the scientific method and the Bible to calculate a date of creation - approximately 6000 years ago. It was a remarkable achievement, but he was wrong. Michio climbs down the layers of rock from which the Grand Canyon is carved to discover that the world must be much older. Meteorites hold the ultimate clues to the formation of the Earth - a staggering 4.6 billion years ago. Michio reveals that, far from being fixed, the Earth has been reshaped with incredible violence. It's usually too slow to witness directly, but inhabitants close to the world's most active volcano, Kilauea, on Hawaii know the Earth's forces all too well as they recover their homes from volcanic ash.
It's almost impossible to conceive of the vastness of Earth time: in an attempt to illustrate the planet's lifespan, Michio travels from the West to the East coast of America each millimetre representing one year. But where do we fit in? Our time seems so insignificant, but we're part of perhaps the greatest story ever told - the story of life itself. The programme looks at bacteria that have been brought to life from a time capsule of rock after 250 million years, encounters creatures in which evolution can be seen in action, and explores the ultimate biological clock - DNA. Michio has his own DNA tested to reveal his ancestral journey all the way back to our first human ancestors in Africa. Finally, the episode concludes with a look into the future to ask where we are ultimately going.
In this four-programme series, string theory pioneer Michio Kaku goes on an extraordinary exploration of the world in search of time. He discovers our sense of time passing and the clocks that drive our bodies. He reveals the forces of time that make and destroy us in a lifetime. He journeys to some of the Earth's most spectacular geological sites to look for clues to the extraordinary depths of time at a planetary level. Finally, he takes us on a cosmic journey in search of the beginning (and the end) of time itself.
Time seems to drive every moment. It's the most inescapable force we feel. But do we experience time from within our minds and bodies or from the outside?
The most powerful effect of time on our lives is the way it limits us. Our knowledge of death is so embedded in our lives and spirituality that, were immortality possible, would we lose the sense that makes us human?
3. EARTH TIME
We hold a unique knowledge of time, realising that it stretches deep into the past, and will continue into the future. How does this affect our sense of who we are?
4. COSMIC TIME
We've always structured our lives based on an unchanging past and a predictable and ordered future. But atomic and cosmic discoveries have changed all that. What is time itself? And will it ever end?