Sir, i've gone through wheeler's delayed choice experiment recently...i've got few couple of doubts in it..Please clarify them...Actually Wheeler wanted an answer for his questionthat "what happens when a single photon, presumably already determined to get detected as part of a two-slit interference pattern, suddenly gets detected in a path coming from only one slit. Does the interference pattern then disappear?" what answer did he get..?? and my doubt is that when we place detection screen we'll see interference pattern and if remove the screen and detect the light from slits through a telescope we 'll know by which slit has the photon come...right...?..what is the inference this observation gives..??it can behave either as wave or particle..right..?? or something else...correct me...if iam wrong antwherein my arguements..Thanking You Sir... With Regards Ashok.