Dear Editor

The search for exotic Dirac fermions in functional materials has been a central theme in condensed
matter physics during the past decade. Most of the observed Dirac fermions materialize in weakly-correlated
systems; identification of Dirac fermions in strongly-correlated materials would offer
insight into their intricate physics. To this end, we turn to the strongly-correlated cerium
monopnictides (CeX), and find an unprecedented type of Dirac fermions which is uniquely distinct
from graphene and previously-discovered topological insulators. The experimental robustness of
these fermions challenge our understanding of correlated magnetic phases, as well as promise
applications in low-power electronics and spintronics devices.

The charge carriers of graphene mimic massless, relativistic electrons with an isotropic speed of
light. In CeX, we find two flavors of massless, relativistic electrons with distinct velocities that
strongly depend on the direction of propagation – their energy-momentum dispersion comprises two
graceful, elliptical cones which surprisingly interpenetrate each other without mixing. While these
strange fermions live only on a two-dimensional surface, each surface flavor originates from a
distinct Moebius-like twist in the quantum wavefunctions of three-dimensional CeX. This precise
correspondence between surface and bulk fermions presents a fascinating case study of holography
in condensed matter physics.

An inward grin

I appreciate that women in science are a minority due to cultural pressures which I hope to negate where I see them. Having never seen any convincing biological evidence, I tend to disbelieve in intrinsic reasons. Neither do I go out of my way to look for biological evidence, because it's a sad endeavor to seek truths which disempower people.  

I am content being a quiet mover in a movement which is, at skin level, dominated by louder movers. The loudest movers are fanatical and I cannot take them seriously. They speak of good and evil, and are astonished when they meet people without their ardor for truth. Though I sympathize, their company is often difficult, conversations are fraught with hard statements with no soft edges. Often the loudest movers are the ones who have been most hurt by these cultural pressures. Though they have recovered enough to empower themselves to help others, they never fully recover and bear the scars of lifelong battle. Frailty, bitterness, grand jagged speeches. Gone is the fluidity of a calculated response, instead emotions run them ragged and betray them as still-victims.

It's refreshing to see fellow quiet movers. I don't find them as often in the debris, but sometimes they betray themselves by a compassionate remark which remains smoothly light-hearted. I grin and pat them on the back. Metaphorically of course! I am never one to betray myself.