"It is impossible to turn back time. Discuss."

As far as time travel is concerned,
possibilities are not allowed to exist,
most insist it is impossible to turn back time.

However, theory states that one can indeed
go back in time, but do not expect
to exceed twenty-four hours.

Longitude splits our world into twenty-four.
In relation to the planet's rotation
upon its daily axis, time
is affected on certain continents.
Thus one may travel to a certain extent.

Sydney to New York
hurls one back thirteen hours.

Having said this,
it is not possible to erase past events
or rewrite history.
The extra time gained
would be lost
were one to travel back to
one's original destination.

Greenwich Mean Time
changes the clocks twice a year.
Daylight hours are kept
in sequence with the sunlight
every spring and autumn.
Time is altered, if only by an hour.

It is arguable therefore
that time can be turned back.
Aforementioned already
that time travel does not change
nor rearrange history.

To invest in this, one must invent
either an impossibility or purchase
the means by which to traverse
the barriers of time and space.

The fastest and most cost-effective solution?
Change the settings on one's clock.