Potential and mass-matrix in gauged N=4 supergravity (2003)
De Roo, M., Panda, S., Trigiante, M., Westra, D. B.
We discuss the potential and mass-matrix of gauged N=4 matter coupled supergravity for the case of six matter multiplets, extending previous work by considering the dependence on all scalars. We...
De Sitter solutions in N=4 matter coupled supergravity (2002)
De Roo, M., Westra, D. B., Panda, S.
We investigate the scalar potential of gauged N=4 supergravity with matter. The extremum in the SU(1,1)/U(1) scalars is obtained for an arbitrary number of matter multiplets. The constraints on the...
Supersymmetric Yang-Mills theory at order alpha'^3 (2002)
Collinucci, A., De Roo, M., Eenink, M. G. C.
We construct the order alpha'^3 terms in the supersymmetric Yang-Mills action in ten dimensions for an arbitrary gauge group. The result can be expressed in terms of the structure constants of the...
Supersymmetric non-abelian Born-Infeld revisited (2001)
Bergshoeff, E. A., Bilal, A., De Roo, M., Sevrin, A.
We determine the non-abelian Born-Infeld action, including fermions, as it results from the four-point tree-level open superstring scattering amplitudes at order alpha'^2. We find that, after an...
On the supersymmetric non-abelian Born-Infeld action (2000)
Bergshoeff, E. A., De Roo, M., Sevrin, A.
We review an iterative construction of the supersymmetric non-abelian Born-Infeld action. We obtain the action through second order in the fieldstrength. Kappa-invariance fixes the ordenings which...
Non-abelian Born-Infeld and kappa-symmetry (2000)
Bergshoeff, E. A., De Roo, M., Sevrin, A.
We define an iterative procedure to obtain a non-abelian generalization of the Born-Infeld action. This construction is made possible by the use of the severe restrictions imposed by kappa-symmetry....
Towards a supersymmetric non-abelian Born-Infeld theory (2000)
Bergshoeff, E., De Roo, M., Sevrin, A.
We define an iterative procedure to obtain a non-abelian generalization of the Born-Infeld action. This construction is made possible by the use of the severe restrictions imposed by kappa-symmetry....
T-duality and Actions for Non-BPS D-branes (2000)
Bergshoeff, E. A., De Roo, M., De Wit, T. C., Eyras, E., Panda, S.
We employ T-duality to restrict the tachyon dependence of effective actions for non-BPS D-branes. For the Born-Infeld part the criteria of T-duality and supersymmetry are satisfied by a simple...
Unstable vortices do not confine (1998)
Achucarro, A., De Roo, M., Huiszoon, L.
Recently, a geometric model for the confinement of magnetic charges in the context of type II string compactifications was constructed by Greene, Morrison and Vafa. This model assumes the existence...
Intersecting Branes in Matrix Theory (1997)
De Roo, M., Panda, S., Van Der Schaar, J. P.
We construct BPS states in the matrix description of M-theory. Starting from a set of basic M-theory branes, we study pair intersections which preserve supersymmetry. The fractions of the maximal...
Gauged Supergravity from Dimensional Reduction (1997)
Bergshoeff, E., De Roo, M., Eyras, E.
We perform a generalised Scherk-Schwarz reduction of the effective action of the heterotic string on T^6 to obtain a massive N=4 supergravity theory in four dimensions. The local symmetry-group of...
Intersections involving waves and monopoles in eleven dimensions (1997)
Bergshoeff, E., De Roo, M., Eyras, E., Janssen, B., Van Der Schaar, J. P.
We consider intersections in eleven dimensions involving Kaluza-Klein monopoles and Brinkmann waves. Besides these purely gravitational configurations we also construct solutions to the equations of...
Intersecting branes and Supersymmetry (1997)
We consider intersecting M-brane solutions of supergravity in eleven dimensions. Supersymmetry turns out to be a powerful tool in obtaining such solutions and their generalizations.
Schiepers, C, Wyndaele, D, Baetens, J, De Roo, M, ...
Multiple Intersections of D-branes and M-branes (1996)
Bergshoeff, E., De Roo, M., Eyras, E., Janssen, B., Van Der Schaar, J. P.
We give a classification of all multiple intersections of D-branes in ten dimensions and M-branes in eleven dimensions that corresponds to threshold BPS bound states. The residual supersymmetry of...
Four-dimensional High-Branes as Intersecting D-Branes (1996)
Bergshoeff, E., De Roo, M., Panda, S.
We show that a class of extremal four-dimensional supersymmetric ``high-branes'', i.e. string and domain wall solutions, can be interpreted as intersections of four ten-dimensional Dirichlet branes....
The eleven-dimensional five-brane (1996)
Bergshoeff, E A, De Roo, M, OrtÃn, Tomas
We consider the action, in arbitrary curved background, of the eleven-dimensional five-brane to second order in the curvature of the worldvolume tensor field. We show that this action gives upon...
We show how the $T$--duality between $D$--branes is realized (i) on $p$--brane solutions $(p=0,\cdots ,9)$ of IIA/IIB supergravity and (ii) on the $D$--brane actions ($p=0,\cdots ,3)$ that act as...
Duality of Type II 7-branes and 8-branes (1996)
Bergshoeff, E., De Roo, M., Green, M. B., Papadopoulos, G., Townsend, P. K.
We present a version of ten-dimensional IIA supergravity containing a 9-form potential for which the field equations are equivalent to those of the standard, massless, IIA theory for vanishing...
Duality symmetry in four-dimensional string actions (1995)
We reduce the dual version of $D=10$, $N=1$ supergravity coupled to $n$ vector fields to four dimensions, and derive the $SL(2,R)\times O(6,6+n)$ transformations which leave the equations of motion...
On realizing the bosonic string as a noncritical $W_3$-string (1994)
Bergshoeff, E., Boonstra, H. J., De Roo, M.
We discuss a realization of the bosonic string as a noncritical $W_3$-string. The relevant noncritical $W_3$-string is characterized by a Liouville sector which is restricted to a (non-unitary)...
On the Cohomology of the Noncritical $W$-string (1993)
Bergshoeff, E., De Boer, J., De Roo, M., Tjin, T.
We investigate the cohomology structure of a general noncritical $W_N$-string. We do this by introducing a new basis in the Hilbert space in which the BRST operator splits into a ``nested'' sum of...
A BRST Analysis of $W$-symmetries (1993)
Bergshoeff, E., Boonstra, H. J., Panda, S., De Roo, M.
We perform a classical BRST analysis of the symmetries corresponding to a generic $w_N$-algebra. An essential feature of our method is that we write the $w_N$-algebra in a special basis such that the...
On the BRST Operator of $W$-Strings (1993)
Bergshoeff, E., Boonstra, H. J., De Roo, M., Panda, S., Sevrin, A.
We discuss the conditions under which the BRST operator of a $W$-string can be written as the sum of two operators that are separately nilpotent and anticommute with each other. We illustrate our...
The Supersymmetric Effective Action of the Heterotic String in Ten Dimensions (1992)
De Roo, M., Suelmann, H., Wiedemann, A.
We construct the supersymmetric completion of quartic $R+R^4$-actions in the ten-dimensional effective action of the heterotic string. Two invariants, of which the bosonic parts are known from...
Realisations of $W_3$ Symmetry (1992)
Bergshoeff, E., Boonstra, H. J., De Roo, M.
We perform a systematic investigation of free-scalar realisations of the Za\-mo\-lod\-chi\-kov $W_3$ algebra in which the operator product of two spin-three generators contains a non-zero operator of...
We quantise the classical gauge theory of $N=2\ w_\infty$-supergravity and show how the underlying $N=2$ super-$w_\infty$ algebra gets deformed into an $N=2$ super-$W_\infty$ algebra. Both algebras...
INCREASED LEVELS OF OSTEOCALCIN (SERUM BONE GLA-PROTEIN) IN RHEUMATOID ARTHRITIS (1986)
GEVERS, G., DEVOS, P., DE ROO, M., DEQUEKER, J.
Serum osteocalcin was measured by radio-immunoassay in 56 patients with rheumatoid arthritis (RA), and in 50 controls. Mean serum osteocalcin levels were significantly higher in patients with RA....
Chiral superfields in N=2 supergravity (1980)
De Roo, M, Vanholten, Jw, De Wit, B, Van Proeyen, Antoine; U0015804
Dupont, P, Orban, G A, Vogels, R, Bormans, G, Nuyts, J, Schiepers, C, ...
To investigate the processing of visual form in human cerebral cortex, we used the PET (positron emission tomography) activation technique to compare the human brain regions that are involved in a...
Dupont, P, Orban, G A, Vogels, R, Bormans, G, Nuyts, J, Schiepers, C, ...
To investigate the processing of visual form in human cerebral cortex, we used the PET (positron emission tomography) activation technique to compare the human brain regions that are involved in a...