Rachel Whiteread

House: a concrete cast of the inside of a house similar to the home where she lived as a child.

From the website linked above: "But what of the space itself, where events happen, where seeming emptiness defines the surrounding physical elements? Is it possible to have a visual relationship with something we cannot see?... The audience must re-evaluate its relationship with the space: emptiness is now solid and a solid form is now empty. That which once surrounded, sheltered, and confined is now gone. And what was thought to be empty is now a visible, identifiable, and physical mass. Whiteread reveals, in fact, that nothing has always been something...

"It's as if Whiteread is paying homage to the ghosts of material objects... Whiteread's works often intimate that something has been lost, but sometimes they reveal the opposite -- sometimes the viewer discovers something they always knew existed but could not identify visually. Her sculptures investigate the relationship between matter and its corresponding negative space, between what we have imagined lost and what we have discovered found."