<div dir="ltr">I obviously can't deep dive into this, but it seems like the type of thing that gets people at FRIAM interested.... 62 year old problem solved...<div><div dir="ltr" class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div></div></div><div dir="ltr"><a href="mailto:echarles@american.edu" target="_blank"></a></div></div></div></div></div></div><div><br></div><div><a href="https://a//www.dailyo.in/technology/indian-mathematician-cracks-1959-problem-and-ramanujan-graphs/story/1/34929.html">https://a//www.dailyo.in/technology/indian-mathematician-cracks-1959-problem-and-ramanujan-graphs/story/1/34929.html</a></div><div><br></div><div> <strong style="color:rgb(86,86,86);font-family:Georgia,serif;font-size:20px;padding:0px;margin:0px;box-sizing:border-box;outline:none">THE 1959 KADISON-SINGER PROBLEM</strong><br></div><p style="padding:8px 0px 0px;margin:0px;box-sizing:border-box;outline:none;color:rgb(86,86,86);font-size:20px;line-height:27px;font-family:Georgia,serif">The original problem that was posed by Kadison and Singer was this: <strong style="padding:0px;margin:0px;box-sizing:border-box;outline:none">If one had to know about the state of a quantum system, would having complete knowledge of its sub systems help understand this system? If yes, to what extent?</strong></p><p style="padding:8px 0px 0px;margin:0px;box-sizing:border-box;outline:none;color:rgb(86,86,86);font-size:20px;line-height:27px;font-family:Georgia,serif">A practical application of this concept was the concept of matrices (yes, the math concept that had brackets and zeros and ones in certain locations). Asking the above question is equivalent to someone asking: <strong style="padding:0px;margin:0px;box-sizing:border-box;outline:none">Could matrices be broken down into more depth and simplified? If yes, how much?</strong></p><p style="padding:8px 0px 0px;margin:0px;box-sizing:border-box;outline:none;color:rgb(86,86,86);font-size:20px;line-height:27px;font-family:Georgia,serif"><strong style="padding:0px;margin:0px;box-sizing:border-box;outline:none">....</strong></p><p style="padding:8px 0px 0px;margin:0px;box-sizing:border-box;outline:none;color:rgb(86,86,86);font-size:20px;line-height:27px;font-family:Georgia,serif">Adam was trying to solve his own different problem. His problem was on similar lines, but different. Adam was trying to reduce a computer network to have less connections, but which could act as effectively as before. This would help them compress data and help in efficient computation.</p><p style="padding:8px 0px 0px;margin:0px;box-sizing:border-box;outline:none;color:rgb(86,86,86);font-size:20px;line-height:27px;font-family:Georgia,serif"><strong style="padding:0px;margin:0px;box-sizing:border-box;outline:none"></strong></p><p style="padding:8px 0px 0px;margin:0px;box-sizing:border-box;outline:none;color:rgb(86,86,86);font-size:20px;line-height:27px;font-family:Georgia,serif">On second thoughts, this seemed to be very similar to a friend's maths problem, which was also known as the Kadison-Singer problem. When Adam Marcus realised he could solve the maths and computer science problem together, he joined forces with the other two specialists, Daniel Spielman and Nikhil Srivastava to work together, and eventually solved the problem.</p></div>