What is a forest? By definition, it is an ecosystem of trees and shrubs. Communities of plants and trees that cover vast areas of the Earth and that are habitats for all sorts of beings including animals and humans, modulators of hydrological flows and soil conservation, constituting one of the most relevant aspects of the biosphere of the globe. But perhaps the relevant question is not "what" is a forest, but "how" is a forest, that is, what makes it possible and, in turn, what is made possible by them? Forests can be found in all regions capable of supporting tree growth except where natural fire rates are too high, or where the environment has been damaged by natural processes or specially human activities. A forest, then, is only possible as a whole, always among many, it is defined by its collectivity, or as a distribution system of organized beings to be able to live among several. And possibly also lots, flocks of humans and non-humans that survive thanks to the biosphere they care for. So "who are you" is not a question but a political operation. I am nothing more than a bunch and nothing less than a flock. It was always you? “How” and no longer “what”. Perhaps there is a whole unknown grammar-forest. A geographical becoming of entangled ontologies, we are only in symbiosis, in heaps, sets and groups. There is only possible life in the middle of an association or better yet, in an association of associations, a relationship or beyond, a relationship of relationships. Grouping, community, collectivity, mass, crowd, gang, flock, mob, rhizome, swarm. On the other hand, quantum entanglement is a phenomenon in which a set of particles can no longer be defined individually, but only as a system with a single wave function, i.e. the states of two or more objects must be described by a state unique that involves all the objects in the system, even when the objects are spatially separated. Light, according to physics, has an indefinite ontology, since it behaves sometimes as a wave and sometimes as a particle. It is not that he is one and/or the other, nor that he is both simultaneously, but that his way of being in the world is (im)possible.Not both, not all, not in between, not simultaneously. Entangled in itself, an indefinite existence. Our planet has already lost a third of its forests in the last 100,000 years, half of them since 1900. What are the (im)possible worlds where we can live a more livable life for plural and diverse human and non-human beings?The aim of this installation is to bring the energy of the woods of Cataluña and entangle them with the Swiss environment. For this we used sensors that measured the electromagnetic variations emitted by the Catalan trees and we translated them into light. We wanted to make a statement and collaborate with the forests, enabling them as the designers of the installation and not just mere passive actors. The forests in these installations are the protagonists, the artists and the ones that are making real life decisions about what kind of experience we are going to have.