For example maybe you need a working time machine at your destination, such that the earliest point possible to travel to is the moment the first time machine was switched on.
Someone who put work and effort into developing time travel will have heard of it. Unless it happened after a complete destruction and rebuild of civilization or two.
There’s an innumerable number of reasons no one showed up, only one of which is that backwards time travel isn’t possible.
For example maybe you need a working time machine at your destination, such that the earliest point possible to travel to is the moment the first time machine was switched on.
One of which is that Stephen Hawking threw a lousy party.
The other one is that most people haven’t herd of it, so I doubt the knowledge of this party will travel that far into the future.
Someone who put work and effort into developing time travel will have heard of it. Unless it happened after a complete destruction and rebuild of civilization or two.
Maybe Stephen Hawking sent hate mail to future humans so now they don’t attend his party out of spite.