Things are being done 'cleanly' so far...
But qunatum mechanics does not prohibit the 'unclean' part...
Expect miracles to happen once in a lifetime..
:-))
Thanks to the God of probability...
Time needs to be understood properly before we can think of any such adventure...
Any such travel will violate Entropy ....when 'y' moment goes back to 'y-1' moment then the entropy decreases...assuming our consciouness to remain continuous ...(or observation can be communicated between two moments)...
Another puzzle solved. What say?