If two lasers are pointed emitting end to emitting end in a vacuum (for lowest divergence), and emit 2 beams of light 180 out of phase, could both beams destructively interfere completely (no light coming from either emitting end after the beams converge)? If the experiment was done under conditions where some of the laser light could scatter, would a "shadow" propagate from the point of convergence to the emitting ends of the lasers (assuming the lasers are far enough apart where this can be reasonably detected)? Where would the energy of the beam go (heat?), assuming the lasers continue to function after the beams converge? Would beams travel into the emitting end of the the opposing laser and interfere with the gain medium?