<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>BALONEY. We could call the alternate (compact) dimensions DARK dimensions, along with dark matter and dark energy, if the term "alternate" bothers you. String Theory lists 11 or 12 of them mathematically, which covers all the particles and forces. <br />Posted by kyle_baron</DIV></p><p>Kyle, as we both know you couldn't recognize bologna if you had Oscar Mayer in your pocket.</p><p>There is no such thing as a dark dimension, except when you refuse to come out into the light. Dimensions are neither dark nor alternate. A manifold is either n-dimensional, for a specific value of n, or it is not. The dimension is the same everywhere, and it must be so as can be rigorously shown. A manifold can be constructed so that in certain directions it is quite small, basically admitting of compact slices that are small when measured in the metric of the manifold, but those dimensions are there all the time, are not some cubby hole where spirits hang out, and are most certainly not "alternate" in any reasonable sense of the word.</p><p>String theory is not a single theory and is not consistent in either the number of dimensions required for the formulation or in what it covers. In fact one of the problems with string theory is that many of its predictions are so far wrong that all that is certain is that the theory need some heavy-duty refinement. String theory and its successor M theory are valid attempts to develop a unified theory of the known forces, but those theories are still in the formative stages and are not ready for prime time.</p><p>String theory also requires supersymmetry, so it not only covers all the particles it covers an entire zoo of them which have never been seen. We may get discover some of the in the scheduled LHC experiments if and when the collider comes back on line. Those experiments could provide some support for string theory by finding supersymmetric particles, or kill it entirely. Supersymmetry is required for string theories and M theory, but string/M theory is not required for supersymmetry so the LHC cannot confirm string or M theories. </p><p><br /><br /> </p> <div class="Discussion_UserSignature"> </div>