M2-branes on a resolved C4/Z4C_4/Z_4

We write down M2-branes on the resolved $C_4/Z_4$ orbifold space. The resolved spatial geometry is such that it interpolates between $R^2\times CP_3$ near the branes and $C_4/Z_4$ asymptotically. The near horizon geometry of these branes is a deformation of $AdS_4\times S^7/Z_4$. An interesting aspect is that for $k=4$ Chern-Simons theory coupling becomes vanishing near the IR cutoff leading to spontaneous compactification to type IIA.Comment: 10 pp; v2: references added; v3: minor change after eq(11

Lifshitz to AdS flow with interpolating p-brane solutions

In continuation with our studies of Lifshitz like D$p$-brane solutions, we propose a class of 1/4 BPS supersymmetric interpolating solutions which interpolate between IR Lifshitz solutions and UV AdS solutions smoothly. We demonstrate properties of these classical solutions near the two fixed points. These interpolating solutions are then used to calculate the entanglement entropies of strip-like subsystems. With these bulk solutions the entropy functional also gets modified. We also make a curious observation about the electric-magnetic duality and the thermal entropy of the Hodge-dual Lifshitz D$p$ brane systems.Comment: 18 pages; v2: minor changes, including a bad typo in the eqs of Sec-(4.3), references adde

Galilean anti-de-Sitter spacetime in Romans theory

The Romans type IIA theory is the only known example of 10-dimensional maximal supergravity where (tensor) fields are explicitly massive. We provide an example of a non-relativistic anti-de Sitter $NRadS_4\times S^6$ background as a solution in massive type IIA. A compactification of which on $S^6$ gives immediately the prototype NRadS background in D=4 which is proposed to be dual to `cold atoms' or unitary fermions on a wire.Comment: 10 pages; change in reference

D2-D8 system with massive strings and the Lifshitz spacetimes

The Romans type IIA supergravity allows fundamental strings to have explicit mass term at the tree level. We show that there exists a (F1,D2,D8) brane configuration which gives rise to $Lif_4^{(2)}\times {R}^1\times S^5$ vacua supported by the massive strings. The presence of D8-branes naturally excites massive fundamental strings. A compactification on circle relates these Lifshitz massive type-IIA background with the axion-flux $Lif_4^{(2)}\times {S}^1\times S^5$ vacua in ordinary type-IIB theory. The massive T-duality in eight dimensions further relates them to yet another $\widetilde{Lif}_4^{(2)}\times S^1\times S^5$ vacua constituted by (F1,D0,D6) system in ordinary type IIA theory. The latter vacua after compactification to four dimensions generate two `distinct' electric charges and a constant magnetic field, all living over 2-dimensional plane. This somewhat reminds us of a similar set up in quantum Hall systems.Comment: 19 pages; minor change