String Theory Hit With New Mathematical Barrier to Cosmic Expansion
Physicists have proven that higher-dimensional braneworld models—a leading framework for reconciling string theory with cosmology—cannot produce the accelerating universe we observe without invoking exotic negative-mass matter. The finding tightens constraints on viable paths to unifying fundamental physics, potentially redirecting billions in theoretical research priorities.
Originaltitel: Higher codimension de Sitter branes
<p>We extend the arguments of Maldacena and N & uacute;& ntilde;ez to include higher codimension brane setups and derive a new no-go theorem. Specifically, we show that, under reasonable assumptions on the energy-momentum conservation and the bulk curvature, codimension-two branes fail to support stable de Sitter solutions. For codimensions higher than two embedded in a compact internal space, we show that negative tension sources would be required. This result places strong constraints on the viability of higher-dimensional braneworld models as a means to obtain de Sitter space within string theory.</p>