241 00:19:57,000 --&amp;gt; 00:20:00,560 because when it's a beam, light behaves like a wave, 242 00:20:00,560 --&amp;gt; 00:20:05,280 creating a classic pattern of light and dark stripes 243 00:20:05,280 --&amp;gt; 00:20:12,520 but it's totally incomprehensible how slngle particles of light can create this wave pattern.