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We study the exact low energy spectra of the spin 1/2 Heisenbergantiferromagnet on small samples of the kagom\'e lattice of up to N=36 sites.In agreement with the conclusions of previous authors, we find that these lowenergy spectra contradict the hypothesis of N\'eel type long range order.Certainly, the ground state of this system is a spin liquid, but its propertiesare rather unusual. The magnetic ($\Delta S=1$) excitations are separated fromthe ground state by a gap. However, this gap is filled with nonmagnetic($\Delta S=0$) excitations. In the thermodynamic limit the spectrum of thesenonmagnetic excitations will presumably develop into a gapless continuumadjacent to the ground state. Surprisingly, the eigenstates of samples with anodd number of sites, i.e. samples with an unsaturated spin, exhibit symmetrieswhich could support long range chiral order. We do not know if these stateswill be true thermodynamic states or only metastable ones. In any case, the lowenergy properties of the spin 1/2 Heisenberg antiferromagnet on the kagom\'elattice clearly distinguish this system from either a short range RVB spinliquid or a standard chiral spin liquid. Presumably they are facets of agenerically new state of frustrated two-dimensional quantum antiferromagnets.Comment: 8 pages including 3 eps-figures, using epsfig packag

First excitations of the spin 1/2 Heisenberg antiferromagnet on the kagomé lattice