|MadSci Network: Physics|
Hi, Unfortunately lasers are unable to produce such a high energy pulse as that of a brick. Of course it would depend on the mass of the brick which you didn't specify ;) So for a 1kg brick you're looking at a 90000000000000000 J laser pulse ignoring relativistic effects which would stop the light brick ever reaching the speed of light. There are lasers being developed at the moment which can blow up missiles and other projectiles but their specifications are classified because they are important for defense puposes. The most powerful lasers have a pulse energy of around 1J so unfortunately it can't be done at the moment. Both the light brick and a pulse of light with the same energy would interact with matter through the electromagnetic force so their effect would be the same. At that sort of speed, the momentum of the light brick would cause it to interact with matter as a wave rather than a particle so it would pass through most matter and cause effects such as interference and diffraction, Ben
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