I will try to keep this as short and concise as possible.
I am a 3rd year PhD student in theoretical physics (condensed matter theory) in a US university. I worked for a certain professor for a year and things seemed to be going well, until he announced one day that he could not continue working with me because his grant application fell through. So I was forced to look for another advisor after I had already started my third year. Nobody else in the condensed matter group wanted to take me because they all claimed not to have funding (this turned out to be a lie, as I later found out). I was finally forced to work for a professor who is 76 years old and does not do research anymore. He has an incomplete project he hasn't worked on for 20 years and I am trying to complete it. I do NOT mind working on an old project. The problem is that whenever I ask him a question or ask for feedback, he ignores me. He does not have any ideas and when I ask for feedback and suggestions on my own ideas and work, he says he doesn't know and I can do whatever I want. I have tried approaching other professors in the department for help, but they refuse to meet/talk to me, saying that they are busy. I am worried that I will never be able to come up with a decent thesis without any sort of guidance, and will almost certainly not have any publications.
My question is: Is there any way I can minimize the damage to my career that this is causing? Is it possible to get a post-doc in theoretical physics without a publication/ with a sub-standard thesis? I am an international student and there are no physics jobs in my country, so any kind of advice on how to proceed would be welcome.
If anyone wants more detailed information, I am happy to provide it.