There is some debate. Thirty years ago, we decided that there were at 11 dimensions (26 with supersymmetry). Now, research at Lawrence Livermore and CERN near Geneva disclose that we may have infinite dimensions in what we call the Multiverse. Our universe supports baryonic mass, dark energy/mass, and compact mass, but we see only 4-dimensions at work: X,Y,Z,T.
The math is a bit involved, but it works and now, we note that it makes sense.
If you deal in antiques, look at an archaic arcade game: Q-Bert. You will see a pyramid of cubes. Note also that you can move only the character, Q-Bert. Other "critters" move at 60 degrees from Q-Bert, as though responding to gravity moving contrary to the gravity everyone else knows.
We found that out long before Q-Bert. That is what makes it so difficult to discern how gravity functions on us, and differently on other universes -- that exist in exactly the same space that we occupy. Newton had gravity down to a science, Einstein showed a bit more of the function of gravity, and now, we know that gravity pulls on infinite "wavelengths" against bodies that "resonate" our gravity at the quantum level.
We know that it is, but not how it works.
The next Nobel Prize in physics will go to the genius who unravels that maddening riddle, makes quantiafiable predictions, and those predictions occur. We'll let the rest of traditional scientific rigor go just to get a useful clue on gravity, that will in turn show us how many dimensions actually exist.