Is it possible to have the effects of a traumatic experience after being told about it without actually experiencing it yourself?

I believe it is. It's empathy. It's a good thing that a person is able to be able to place themselves in someone else's shoes.

Experiencing stress through someone else is very much a real thing. Many people feel for the victims of the trauma and sometimes live it through them. The best way to get over this is to help the actual victim to recover, and then you should naturally recover on your own.

Some text books state there is a phenomenon called "vicarious trauma" which occurs by hearing about the experience without having actually been through it.

Yes, it happened to me when I found out my mom was abused by her boyfriend. I was completely convinced that it was my fault and had a difficult time forgiving myself. It still affects me to this day, but I have finally convinced myself that it was not my fault.

Yes you can experience trauma vicariously, especially if you are very empathetic. The more empathetic you are the more you may take one someone's pain as your own.

It definitely is. Especially if the experience was experienced by someone who is very close to you, in which case I think it's a natural empathetic response.

Absolutely. Mirror neurons allow us to feel empathy, and to actually experience the feelings of others as though we are experiencing them ourselves. https://en.wikipedia.org/wiki/Mirror_neuron

I believe it is possible, the mind is a powerful organ that can force you to believe things that are not true.

Hearing someone bad experience especially if it is someone who is close to us can trigger a lot of anxiety.