Magnetic fields and time travel

[Time_Travel_Experiment]

Time travel entails inducement and manipulation of a time dilation field, which is currently pure science fiction. But, hypothetically speaking, it may be possible for a very technologically advanced civilization to construct a time machine...  

Construct a time machine with magnets...  

Tsagas found that the magnetic tension in bent magnetic field lines tends to flatten the surrounding space. Researchers often assume that the fields were too weak to have much effect, but Tsagas’s results suggest that whenever the curvature of space is large, even a small field can have an effect.

These guys are cosmologists so engineering propulsion devices by manipulating the stiffness of space-time is not their main interest... It would probably also require some very powerful magnetic fields for an anti-gravity craft to levitate near the surface of the Earth... 
Magnetism stiffens space-time...  

Tsagas spotted something no one had seen before: A term in the equation showed that magnetic fields transfer their properties to the very fabric of space-time itself. Like rubber bands under tension, magnetic field lines try to remain as straight as possible. The fields transmit that tension to space-time...

Chronons are hypothetical particles of time. Hypothetically speaking “anti-chronons” could be used in a time travel scenario. The late Physicist Richard Feynman proposed that anti-matter positrons are simply electrons moving backwards in time, hence anti-chronons might also be chronons moving backwards temporally, thus, they generate anti-time.

Mach's principle is an interesting conjecture. Regarding the hypothetical concept of temporally rewinding the universe to a previous era, our time traveler remains within a local bubble of forward moving time. This seems equivalent to generating a wormhole. The universe 

from our sheltered perspective as we look out the window of our time machine... 
In order for successful time travel into the history of our past, gravitational locking to the surface of the Earth is a necessity. Thankfully gravity works the same in reverse time as it does in forward time. Certain laws of physics, like gravity, are symmetric with respect to time.  Would the time machine become invisible to observers as it traveled into the past? I think it might which points to the possibility of multiple universes...