Recent observations suggest that the cosmological equation-of-state parameter w is close to−1. To say this is to imply thatw could be slightly less than−1, which leads to R.Caldwell’s “phantom cosmologies”. These often have the property that they end in a “Big Smash”, a final singularity in which the Universe is destroyed in a finite proper time by excessive expansion. We show that, classically...

Let V be a simple vertex operator algebra and G a finite automorphism group of V . It was shown in [DY] that any irreducible V -module is a completely reducible V G-module. In this paper, we show that any g-twisted V -module is also a completely reducible V G-module if V is g-rational. For each g ∈ G, a g-twisted Zhu algebra Ag,n(V ) plays an important role, but the given product in Ag,n(V ) de...

We establish a twisted analog of our recent work on vertex representations and the McKay correspondence. For each finite group Γ and a virtual character of Γ we construct twisted vertex operators on the Fock space spanned by the super spin characters of the spin wreath products Γ ≀ S̃n of Γ and a double cover of the symmetric group Sn for all n. When Γ is a subgroup of SL2(C) with the McKay virt...

Starting with a spectral triple on unital C⁎-algebra A an action of discrete group G, if the is uniformly bounded (in Lipschitz sense) reduced crossed product A⋊rG constructed in [23]. The main instrument Kasparov external product. We note that this construction still works for twisted products when appropriate sense. Under suitable assumptions we discuss some basic properties resulting triples...

We show that homologically trivial algebraic cycles on a 3-dimensional abelian variety are smash-nilpotent.

One way to increase the heat transfer is to use perforated twisted tapes with different hole diameters, which largely improve heat transfer with an increase in the heat transfer area at the constant volume and more mixed flow. In the previous studies, the effect of nanofluids with perforated twisted tapes is less studied. In this work, the performance of water / iron oxide nanofluid in a double...