Via ssh: Open remote pdf without saving locally I would like to connect to my office computer (running Ubuntu) via ssh and then open a pdf from the office computer on my macbook (similar to xdg-open in ubuntu) with the program associated with pdfs by default (for now, Viewer). 

I would like to do so without first saving the pdf locally. Preferably, if the pdf gets changed on my office computer, I should see the changes without refreshing the command.

How can I achieve this?
Take a look at SSHFS. This allows you to mount a filesystem over ssh. There's a good tutorial here.

Essentially, you will mount the filesystem from your office computer and it will appear as a mounted volume on your mac. Instead of file accesses reading/writing to a local disk, they read/write across the ssh connection to the disk on your office computer.

Since it's a mounted volume, all the local mac commands to open files work with native associated applications as you would expect. (e.g. in Terminal : open somefile.pdf)