%0 Journal Article %T Hubble Scale Dark Energy Meets Nano Scale Casimir Energy and the Rational of Their T-Duality and Mirror Symmetry Equivalence %A M. S. El Naschie %J World Journal of Nano Science and Engineering %P 57-67 %@ 2161-4962 %D 2015 %I Scientific Research Publishing %R 10.4236/wjnse.2015.53008 %X We establish that ordinary energy, Casimir energy and dark energy are not only interlinked but are basically the same thing separated merely by scale and topology. Casimir energy is essentially a nano scale spacetime phenomenon produced by the boundary condition of the two Casimir plates constituting the Casimir experimental set up for measuring the Casimir force. By contrast dark energy is the result of the cosmic boundary condition, i.e. the boundary of the universe. This one sided M?bius-like boundary located at vast cosmic distance and was comparable only to the Hubble radius scales of the universe. All the Casimir energy spreads out until the majority of it reaches the vicinity of the edge of the cosmos. According to a famous theorem due to the Ukrainian-Israeli scientist I. Dvoretzky, almost 96% of the total energy will be concentrated at the boundary of the universe, too far away to be measured directly. The rest of the accumulated Casimir energy density is consequently the nearly 4% to 4.5%, the existence of which is confirmed by various sophisticated cosmic measurements and observations. When all is said and done, the work is essentially yet another confirmation of Witten¡¯s T-duality and mirror symmetry bringing nano scale and Hubble scale together in an unexpected magical yet mathematically rigorous way. %K Mirror Symmetry %K Casimir Energy %K Dark Energy %K Zero Point Vacuum Energy %K T-Duality %K Nano Scale-Hubble Scale %K Mö %K bius Holographic Boundary %K Dvoretzky¡¯s Theorem %K Banach-Tarski Theorem %U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=58120