Nonextremal black holes in gauged supergravity and the real formulation of special geometry

We give a rather general recipe for constructing nonextremal black hole solutions to N=2, D=4 gauged supergravity coupled to abelian vector multiplets. This problem simplifies considerably if one uses the formalism developed in arXiv:1112.2876, based on dimensional reduction and the real formulation of special geometry. We use this to find new nonextremal black holes for several choices of the prepotential, that generalize the BPS solutions found in arXiv:0911.4926. Some physical properties of these black holes are also discussed.Comment: 26 pages, uses JHEP3.cls. v2: Minor corrections, 1 ref. adde

Euclidean Supergravity in Five Dimensions

We construct a 5D, N = 2 Euclidean theory of supergravity coupled to vector multiplets. Upon reducing this theory over a circle we recover the action of 4D, N = 2 Euclidean supergravity coupled to vector multiplets.Comment: 13 page

Non-extremal black hole solutions from the c-map

We construct new static, spherically symmetric non-extremal black hole solutions of four-dimensional ${\cal N}=2$ supergravity, using a systematic technique based on dimensional reduction over time (the c-map) and the real formulation of special geometry. For a certain class of models we actually obtain the general solution to the full second order equations of motion, whilst for other classes of models, such as those obtainable by dimensional reduction from five dimensions, heterotic tree-level models, and type-II Calabi-Yau compactifications in the large volume limit a partial set of solutions are found. When considering specifically non-extremal black hole solutions we find that regularity conditions reduce the number of integration constants by one half. Such solutions satisfy a unique set of first order equations, which we identify. Several models are investigated in detail, including examples of non-homogeneous spaces such as the quantum deformed $STU$ model. Though we focus on static, spherically symmetric solutions of ungauged supergravity, the method is adaptable to other types of solutions and to gauged supergravity.Comment: 57 pages. Minor changes to the introduction, typos corrected and references added. Accepted for publication in JHE

Universal Blockchain Assets

We present a novel protocol for issuing and transferring tokens across blockchains without the need of a trusted third party or cross-chain bridge. In our scheme, the blockchain is used for double-spend protection only, while the authorisation of token transfers is performed off-chain. Due to the universality of our approach, it works in almost all blockchain settings. It can be implemented immediately on UTXO blockchains such as Bitcoin without modification, and on account-based blockchains such as Ethereum by introducing a smart contract that mimics the properties of a UTXO. We provide a proof-of-concept implementation of an NFT that is issued on Bitcoin, transferred to Ethereum, and then transferred back to Bitcoin. Our new approach means that users no longer need to be locked into one blockchain when issuing and transferring tokens

The r-map, c-map and black hole solutions

We consider various geometrical and physical aspects of the r-map and c-map, which are two maps induced by the dimensional reduction of 5d and 4d, N = 2 supergravity coupled to vector multiplets respectively. We treat reduction over a spacelike or timelike dimension on an equal footing, and prove, for the first time, that the target manifold in the image of the timelike c-map is para-quaternion Kahler. In order to do this we provide a new formulation of projective special Kahler geometry based on real Darboux coordinates, which is useful both mathematically and physically in its own right. As an application we investigate how the r-map and c-map can be used to generate new stationary black hole solutions. In four dimensions we construct new extremal non-BPS solutions, and in both four and five dimensions we construct new non-extremal solutions. We also take the first steps towards constructing new rotating solutions, though at this stage we only recover known solutions. The systematic and geometrical nature of these constructions allows us to gain a deeper understanding of many familiar properties of black holes in supergravity, such as the attractor mechanism and the transformation of BPS into non-BPS black holes using a field rotation matrix. We also observe an interesting and novel feature relating to non-extremal black holes: in order for solutions to correspond to non-extremal black holes with finite scalar fields we find that the number of integration constants must reduce by half. This suggests that non-extremal black holes always satisfy first order equations similar to their extremal counterparts. For STU-like models all calculations are performed explicitly

The adenovirus type 2 protease : generation and characterisation of monoclonal antibodies and their use in determining the subcellular distribution of the protease within lytically infected cells

Production of mature infectious adenovirus type 2 depends on the action of the L3 coded 23kd protease which is known to cleave 7 virus proteins and the host cell proteins cytokeratin K7 and K18. Previous studies have shown the enzyme to be a cysteine proteinase with a novel mechanism of activation requiring the presence of an 11 residue peptide derived from the C-terminus of virus structural protein pVI. It has been proposed that the protease is activated within the assembled virion, although other evidence suggests that the protease is active outwith the virus particle, and is partly responsible for the degradation of the intermediate filament system prior to virion release from the infected cell. The subcellular localisation of the 23kd protease during productive adenovirus infection was investigated using a panel of monoclonal antibodies generated during the course of this study. The monoclonal antibodies were partially characterised and those of interest were epitope mapped using a combination of techniques which included limited and chemical proteolysis, and deletion mutagenesis of the recombinant protein, and screening against overlapping peptides corresponding to specific regions within the 23kd protease. The viral 23kd protease, capsid protein pVIII, and the Ll-52kd probable scaffold protein were shown to colocalise within virus-induced intranuclear clear amorphous inclusions late in infection (24 h.p.i onwards). These inclusions were typically associated with crystalline arrays of assembled virions and are believed to be the same sites which contain relocated PML during the earlier stages of infection. The stmctural appearance of these inclusions varied depending on the fixation method used. The distribution of the viral protease, PML and another cellular protein P80-coilin during the late-phase of nuclear transformation was investigated with possible cleavage of both cellular proteins also partially determined. The viral protease and protein pVIII were also shown to colocalise within cytoplasmic structures but were not found to be associated with cytokeratin K18. The degradation of cytokeratin K18 occurred as early as 20 to 22 h.p.i although the intranuclear distribution of pVI at this stage of infection suggested that the viral protease may be regulated by an as yet unknown mechanism. Isoforms of recombinant wild type 23kd protease (but not Ad2tsl) were detected in vitro which suggested that dimerisation may be an in vivo regulatory mechanism, possibly involving intranuclear trafficking