Time travelling into the past is easy.
This is because it is already fully calibrated and documented.
I know for a fact, for example, that I went to the supermarket yesterday to buy a disappointing can of baked beans - and that I also did the same on Thursday.
Ignoring any dietary or social concerns as to why I am spending so much of my time buying individual cans of baked beans at supermarkets, these two moments are now known to me as fixed points in space and time. They are also, importantly, noted as ones that I would not be overly eager to revisit - whilst that wondrous moment in April, where a shortage of my regular brand lead to the replacement baked beans becoming unexpectedly magnificent, might be a more tempting prospect.
The same cannot be said of travelling to the future. No matter how many quantum physicists politely explain to us that time is a concept we afford ourselves to make sense of what is really around us, the simple fact remains that quite a lot of stuff hasn't happened to us yet.
As such, picking a decent destination in an unknown future is a rather haphazard enterprise which could easily lead to disappointment.
And so to Flashforward by Robert J. Sawyer, where Lloyd is suddenly sent 20 years into his future for 2 minutes. The aforementioned lack of available planning though means that, when he arrives, all he is able to squeeze in is a quick grope of a woman's naked breast and a trip to the bathroom to urinate.
As time travelling journeys go this is a disappointing one to say the least, but Lloyd is much better off than many others. For the whole of humanity also experienced the same jump to their own personalised futures - whilst the ones who merely blacked out presume that will have died in the intervening time, so much chaos ensues.
It is an interesting, if not entirely successful, novel but one that is keen to make a salient point:
No matter where we go, for how long or who with, we always end up in the present - and this happens to us so relentlessly it is almost like we are meant to be exactly we are, and absolutely nowhere else.
Artwork : Baked beans of unknown origin.