Speaking of mind-bending ideas. You should look into Kurt Godel's work into the effects of Rotating Universes. Kurt Godel showed that such universe would allow for time travel:
http://www.brainpickings.org/index.html/2...me-travel/
Even though we don't live in a rotating universe - I find it interesting from a philosophical perspective. For thousands of years - philosophers discussed time in the same way we discuss God. As something completely unknowable. But since Einstein - we have being able to learn intriguing things about time. And that is as delightful to me as it would be if people - one day - were able to know a few random things about the nature of God. It just seems amazing that science has enabled us to get some kind of grasp over such a mysterious field.
People don't realise that time dilation doesn't just occur over vast speeds. It also occurs over vast distances (due to the curvature of space-time caused by gravity).
Here is something I got from an excellent Brian Greene book - The Fabric of the Cosmos: Space, Time, and the Texture of Reality (the best popular physics book I have ever read. And my dad - a retired physics teacher - said the same thing):
You are sat here. Right now. Reading this. Probably (like me) in your bedroom.
Well - imagine an alien called Bob sat in his kitchen drinking a cup of alpha-splurge (or whatever it is they drink) two million light-years away. If you were 'God' you could see that you on the internet - and Bob millions of light-years away are existing at the exact same time - ie. NOW!
Well - imagine you now decide to get up and go to the toilet. As a result of that simple action - you and Bob no longer share the same geometric slice of 'space-time' - as a result Bob is now on a different slice of space-time which is 200 years behind yours. So - he doesn't even exist anymore.
To visualise this consider that whilst two points may be very close to each other - when sent as two straight lines across millions of light-years they will end up very far apart.
And now - the bell rings and you go answer the door. And now - from your perspetive of 'now' - Bob is now 400 years in the future - and has being dead for hundreds of years.
If there were a way to send your father to a planet millions of light-years away. You would be in weird situations where - depending on where you are located in your house - your father would not have even being born yet.
It is fascinating stuff. And a totally different take on relativity to that usually taught in books. You should check out the Brian Greene book for more information. I used to love all this stuff - but these days I concentrate on economics.
http://www.brainpickings.org/index.html/2...me-travel/
Even though we don't live in a rotating universe - I find it interesting from a philosophical perspective. For thousands of years - philosophers discussed time in the same way we discuss God. As something completely unknowable. But since Einstein - we have being able to learn intriguing things about time. And that is as delightful to me as it would be if people - one day - were able to know a few random things about the nature of God. It just seems amazing that science has enabled us to get some kind of grasp over such a mysterious field.
People don't realise that time dilation doesn't just occur over vast speeds. It also occurs over vast distances (due to the curvature of space-time caused by gravity).
Here is something I got from an excellent Brian Greene book - The Fabric of the Cosmos: Space, Time, and the Texture of Reality (the best popular physics book I have ever read. And my dad - a retired physics teacher - said the same thing):
You are sat here. Right now. Reading this. Probably (like me) in your bedroom.
Well - imagine an alien called Bob sat in his kitchen drinking a cup of alpha-splurge (or whatever it is they drink) two million light-years away. If you were 'God' you could see that you on the internet - and Bob millions of light-years away are existing at the exact same time - ie. NOW!
Well - imagine you now decide to get up and go to the toilet. As a result of that simple action - you and Bob no longer share the same geometric slice of 'space-time' - as a result Bob is now on a different slice of space-time which is 200 years behind yours. So - he doesn't even exist anymore.
To visualise this consider that whilst two points may be very close to each other - when sent as two straight lines across millions of light-years they will end up very far apart.
And now - the bell rings and you go answer the door. And now - from your perspetive of 'now' - Bob is now 400 years in the future - and has being dead for hundreds of years.
If there were a way to send your father to a planet millions of light-years away. You would be in weird situations where - depending on where you are located in your house - your father would not have even being born yet.
It is fascinating stuff. And a totally different take on relativity to that usually taught in books. You should check out the Brian Greene book for more information. I used to love all this stuff - but these days I concentrate on economics.