antony

Warm greetings I have recently been introduced to QED by reading a book on the subject, and was wondering if you would be kind enough to help me clarify my understanding thereof….. When ‘light’ is shone upon a potentially reflective surface, in simple terms, the majority of photons reflect at an angle equal to the angle with which they originally shone upon the surface. My query concerns the photons that reflect with an angle other than that with which they approached. When the parts of the surface that prevent those photons from been detected are ‘removed’ and the photons can be detected, is it because those removed angles of reflection were interfering with the others (ie they hit the contrasting photons and are hence prevented from reaching the detector), or is there another explanation? I guess I don’t quite understand how photons combine, as surely without interference from conflicting ‘amplitudes’, the photons, however few of them are received by the detector, would still be detected!? My other query concerns the colour of quarks….. if three quarks are needed to create a proton for example (where one of each colour quark is required), and those quarks cannot exist independently (other than in a quark anti-quark pair), then does this mean that gluons are only able to change the colour of quarks outside the nucleus? Or are more than one colour changed at the same time? Many thanks antony