Hey everyone. I was recently on youtube, looking at 4-d objects, when I came across a comment which caught my eye: "You're forgetting Gravity. Without gravity there is no xyz and without two large bodies there is no concept of time. Therefore, gravity must be included as a dimension. They are known as XYZTG, and basic physics explains. However, quantum physics predicts that there my be more than that, probably even 11. I won't go into all of them but given enough time I guess I could do a few if you really want me to." Ignoring any technical mistakes that he might have in his understanding, I'm curious if the underlying idea is correct. Is gravity a dimension? Thank you. -Tim edit: This post possibly belongs in the string theory forum. If that's the case, sorry.