In the meanwhile find_package(Torch REQUIRED) was sucessful. I did this:
wget https://download.pytorch.org/libtorch/nightly/cpu/libtorch-shared-with-deps-latest.zip
unzip libtorch-shared-with-deps-latest.zip

But know I got the following error, if I want to import the torch:
fatal error: torch/script.h: No such file or directory
 #include <torch/script.h> // One-stop header.
          ^~~~~~~~~~~~~~~~
compilation terminated.

Also I did this guide https://pytorch.org/cppdocs/installing.html 6, which worked. But I would like to compile a larger project with catkin_make.
Has anyone experience with that?