Can you start bounty here on physics meta if your question didn't receive enough attention for example as you can do on the other websites in the network outside meta?
In short, no.
Child metas are designed to have no impact on reputation whatsoever. As a result, you can't use bounties to attract attention to your question. There are a few things you can do, however:
Post the question you asked in chat. Most of the active regulars are active there, and they can help you out.
Write a very catchy title for your question. Believe me, I had a couple of my questions top the hot questions list merely due to catchy titles. This is a very sure way to get attention.