[AlbionGirl]

Do ten dimensions exist? And if so, how were they discovered, and how is their existence proved? If these are dumb questions, you'll have to forgive me, as I'm not very educated in this subject.

[Riley]

Do ten dimensions exist? And if so, how were they discovered, and how is their existence proved? If these are dumb questions, you'll have to forgive me, as I'm not very educated in this subject.

Neither am I, I am an interested layman. However, I can recommend a fantastic book or two that approaches the concept in pretty down-to-earth language:

Dr. Michio Kaku's excellent book "Hyperspace". I have also heard him on the radio from time to time. He was a grunt in Vietnam, BTW.

Hyperspace

This one won't cost a dime, it's a classic reprinted on the Net. The point of the tale is to illustrate the way we would appear from the vantage point of a fourth spatial dimension by looking at and interacting with mythical flat creatures that inhabit two dimensions.

Flatland A romance of many dimensions

[<1/1,000,000th%]

The extra dimensions have not been observed. The particles that string theory predicts have not been observed. The theory itself is background dependent, meaning that you have to tweak it to fit observed data.

I've predicted elsewhere that it will eventually fall to some form of quantum gravity, but it's still early. ;)