Now I get:

ollecting package metadata (repodata.json): done
Solving environment: - 
Found conflicts! Looking for incompatible packages.
This can take several minutes.  Press CTRL-C to abort.
failed                                                                                                                                                                         
                                                                                                                                                                               
UnsatisfiableError: The following specifications were found to be incompatible with a past                                                                                     
explicit spec that is not an explicit spec in this operation (cudatoolkit):

  - pytorch==1.8.0 -> cudatoolkit[version='>=10.1,<10.2|>=10.2,<10.3']

The following specifications were found to be incompatible with each other:



Package cudatoolkit conflicts for:
cudatoolkit=11.0