When people die and God doesn't intervene to raise them immediately they(their spirit) will descend to the kingdom of death or what is known as the world of the dead.
Here's their condition, their exact condition:
- They will not be aware of themselves(no awareness)
- They will no longer remember God(and everything else)/no memory
- They will not able to register the passage of time at all
Note that the world of the dead is not heaven nor it is hell so I can't say for heaven or hell I only know the condition of the dead in the kingdom of death(world of the dead). Most today's Christians do not accept the concept of the world of the dead and people still descending to it even to this day.
It's actually a blessing not to be aware of the passage of time in the world of the dead as the dead may have to wait for quite some time before being raised and judged.