3. Time travel ABILITY TO TRAVEL TO ANY POINT IN SPACE FUTURE TRANSFORMED INTO PAST WITH PRESENT LASTING FOR FLEETING MOMENT TIME- FOURTH DIMENSION OF UNIVERSE ALBERT EINSTEIN’S THEORY OF RELATIVITY LAID THE FOUNDATION FOR THEORETICAL POSSIBILITY OF TIME TRAVEL

4. THEORY Einstein’s 1 st major contribution to study of time-”special theory of relativity” Time is relative to speed RELATIVITY STATE-if one were to move away from the earth at relativistic velocities and return,more time would have passed on earth than for the traveler.

5. TIME TRAVEL TO THE PAST TIME TRAVEL TO THE PAST IS THEORETICALLY ALLOWED USING THE FOLLOWING METHODS 1) TRAVELLING FASTER THAN THE SPEED OF LIGHT 2)USE OF COSMIC STRINGS AND BLACK HOLES 3)WORMHOLES

6. TRAVELLING FASTER THAN SPEED OF LIGHT Relativity states- velocity of an object reaches speed of light, time slows down Scientist have discovered that even at the speed of space shuttle, astronauts can travel a few nanoseconds into the future.

7. BLACK HOLES When stars reach the end of their life, they collapse under the pressure of their own weight. This implosion creates BLACK HOLES. Gravitational fields is very strong

8. MASSIVE SPINNING CYLINDERS Developed by Frank Tipler If cylinder spins fast enough about its long axis, then a spaceship flying around the cylinder on a spiral path could travel back in time.

9. WORMHOLES Are wormholes tunnels for time travel???? Wormholes are theoritical shortcuts through space and time. Tunnel like connection through space time

10. WORMHOLES It has two mouth connected by a throat Provide path that traveler could follow Theoretical No experimental evidence

11. EXPERIMENTS CARRIED OUT Delayed choice quantum eraser by -MARLAN SCULLY Experiment by LIJUN WANG