How can it be deduced general relativity from planck length?
Question doesn't make sense. Plank length is just an arbitrary length. That's like asking how can we deduce GR from the meter or the foot or the mile.
Do you mean how can the classical theory of general relativity be deduced from quantum Plank scale physics?
The question is certainly drastically condensed but it is not meaningless; it is just unconventional and unpublished.
Can you then restate it so it makes sense and is meaningful?
Blackforest has PM'd me indicating that his answer would not be within the forum rules so I still have no information that would lead me to believe that the OP's question makes any sense. Garrolu, can you clarify your question?
In some way parented with your approximate formulation you may eventually appreciate the discussion exposed here:
[arxiv:gr-qc/9904026v2, 14 April 1999] "On gravity and the uncertainty principle".
I hope you enjoy it and perceive the strong logical correlation between the correct utilization of the Heisenberg's uncertainty principle and the possibility to get a connection with the theory of relativity.
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