Al Murray tweeted an article in which the esteemed physicist Stephen Hawkings said that he had evidence that time travel would not be possible saying, "I gave a party for time-travelers, but I didn't send out the invitations until after the party. I sat there a long time, but no one came." But in fact all he has proved is that time travellers don't want to party with Stephen Hawkings. They maybe got the invite and said, "Oh sorry, I'm doing something else that day." To which Hawkings might have replied, "But you've got a time machine. You can come any time you like." And they'd have had to make up some bullshit about some events being unchangeable in time, like they have to in Doctor Who all the time.
There's also the possibility that the time travellers didn't turn up because Stephen Hawkings doesn't turn out to be all that big a deal in the future. Maybe his theories have all been discredited (not least the one where he says he's proven that time travel isn't possible, when it clearly actually is). If you could time travel now then you wouldn't go back to meet a scientist who thought that the sun moved round the earth, it would be embarrassing. Hawkings might be so discredited that people in the future don't even know who he is and thus didn't see his invite in any case. I think we can extrapolate from this lack of interest that Hawkings is definitely wrong about everything. That is all his experiment has shown. It's his only successful work in science, to prove that everything that he says is a load of shit. Well done Hawkings, you idiot.
@olliebean pointed out that Hawkings was stupid to say that no one came to the party as now time travellers won't bother going as they already know they didn't make it. Which is a good point. Time travelling can't be without risks and even if only one in every thousand trips ends with the machine exploding, killing you and ripping a hole in the space time continuum, then you still wouldn't want to take the chance. Especially if you had documented evidence that you didn't show up. To attempt it would be like signing your own death warrant (and maybe destroying the Universe). So Hawkings' experiment is ruined by him and his/his computer's big blabber mouth.
And ultimately he's forgotten that some time travellers might have been on their way but arrived a bit early (or were just nervous about being the first to arrive) so popped into the nearest pub for a drink and fell in love with the barmaid and just spent all their time here trying to get off with her, forgetting all about their mission. It's known in time travelling as the Gary Sparrow constant. A force stronger than gravity. The force of the paucity of ambition.
I think it's unlikely that physical time travel will ever be possible, but that doesn't meant that we won't be able to see into the past. If we can create a powerful enough telescope then we can send that out into space at the speed of light and it can look back at us at the speed of light and thus be able to see things that have already happened (as long as they were outdoors). There's every chance that future time travellers were there, watching Stephen Hawkings eating crisps and drinking pop on his own and laughing at him for having the worst party ever. When they'd heard the music he was playing and seen the supermarket own-brand snacks on offer they would be glad that they hadn't been able to make it along.