Current Events… Optics 21 Jan 2021 Here are some odds and ends to ponder today. https://www.youtube.com/watch?v=Q-07Nq9bqkA&feature=emb_logo https://www.youtube.com/watch?v=MgvT1bgK3uQ https://www.youtube.com/watch?v=8B85SRZJsCg
