What is the chance of getting a PhD position in Germany in physics? [duplicate]

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• How difficult is it to get a paid PhD studentship in physics in Germany? 3 answers

What is the chance of getting a PhD position in Germany in physics taking into account that i have obtained my Master degree from a German university ?

I am 30 years old and i have just finished my master study.

Do my old age play a pivotal rule ?

What are the prerequisites of getting a paid positions ?

Thanks a lot