# Time & Distance: Brian Greene's Theory Explored

• kwerk
In summary, Brian Greene discusses the concept of time dilation in his article "The Time We Thought We Knew." If a person were to travel in a spaceship at close to the speed of light for six months and then return to Earth, they would have aged only one year while those on Earth would have aged 7,000 years. However, if the spaceship were to fly in circles close to Earth, it would appear to have traveled 7,000 years to those on Earth, but the person inside the spaceship would have experienced only one year. This is due to the effects of time dilation at high speeds.

#### kwerk

In Brian Greene's article The Time We Thought We Knew, he writes:

"Were you to board a spaceship, head out from Earth at 99.999999 percent of light speed, travel for six months and then head back home at the same speed, your motion would slow your clock, relative to those that remain stationary on earth, so that you'd be one year older upon your return -- while everyone on Earth would have aged about 7,000 years."

What if you instead flew the spaceship in close circles around the Earth (close enough to be observed). Would people on Earth observe you flying for 7000 years? Inside the spaceship you should experience 1 year, so would you have traveled 1 light year or 7000 light years?

Or did you travel both distances? 7000 viewed from Earth but only 1 viewed from inside the spaceship.

kwerk said:
What if you instead flew the spaceship in close circles around the Earth (close enough to be observed). Would people on Earth observe you flying for 7000 years?
Yes.

kwerk said:
Inside the spaceship you should experience 1 year, so would you have traveled 1 light year or 7000 light years? Or did you travel both distances? 7000 viewed from Earth but only 1 viewed from inside the spaceship.
This is basically right, except that in your own frame you traveled zero distance, while the Earth moved.

## 1. What is Brian Greene's theory of time and distance?

Brian Greene's theory suggests that time and distance are not fixed concepts, but rather are relative and can be affected by factors such as gravity and speed. He proposes that the universe is made up of tiny vibrating strings, and the way they vibrate determines the properties of space and time.

## 2. How does this theory impact our understanding of the universe?

Greene's theory challenges our traditional understanding of space and time, and opens up the possibility of a multi-dimensional universe. It also has implications for the study of black holes and the Big Bang theory.

## 3. Is there evidence to support Greene's theory?

There is currently no direct evidence to support Greene's theory, as it is still a theoretical concept. However, many of the predictions made by string theory, on which Greene's theory is based, have been confirmed through experiments and observations.

## 4. What are the potential implications of this theory?

If Greene's theory is proven to be true, it could revolutionize our understanding of the universe and potentially lead to new technologies and advancements in science. It could also provide a more complete and unified understanding of the laws of physics.

## 5. How does this theory relate to other theories of time and distance?

Greene's theory is one of many theories attempting to explain the nature of time and distance, such as Einstein's theory of relativity and quantum mechanics. While there may be overlap and connections between these theories, they each offer unique perspectives on the complex concepts of time and distance.