So when you die your heart stops and your dynamic breath wanders fleetingly through Gyia and the breath of the dynaverse over large space time.
It is very unlikely you can convince the living universe to produce their spirit in a transparent form above the table that's very much likely to be a hoax.
However the alive loved one is alive across their life and in fleeting moments in grander time from the pretigistal view moving to a point of self reflection with an eternal reflection and multiple self-reflection co-ordination all the way to submerging back into the eternal reflection in the mind of god.
Yes such a person has often spent a reasonable amount of time with the lost one.
This means you can lightly connect with them before when they were alive which is still happening and open up your dreams for them to enter well.
Even in psychological terms it's important for a good memory to remain and resonate well when it does.