While I was at Readercon, I learned that Kathryn Cramer's father John is a physicist here at the University of Washington. This rung vague sorts of bells, because I remembered reading an article several years ago about the Transactional Interpretation of quantum mechanics which I believed to be by one John Cramer. Today, I finally got around to tracking the article down, and the Cramers John are in fact one and the same. It's quite a good article, too. You can read a longer and more detailed version here. It outlines an alternative interpretation of quantum mechanics, the Transactional Interpretation, which I think has great conceptual advantages over the standard Copenhagen Interpretation, one of them being that it isn't silly. The Copenhaged Interpretation is very silly indeed. Concepts like 'observers' and 'measurement' and sometimes even 'consciousness' enter into its descriptions of microscopic phenomena, where such things patently should not be. And there isn't even a convincing rationale for why they should be there. It seems to me to veer dangerously close to solipsism in a sense; if measurement can really change the state vector, the state vector is not an objective, external, physical entity, but some kind of conceptual gimmick, and the theory is not a physical theory at all, but a theory of a model inside our heads. That is very unsatisfying. Cramer's Transactional Interpretation avoids all this, I think elegantly, using advanced and retarded waves. Anywho, read the article, he describes it better than I would.

He uses the term 'time stream' once or twice, which I think is a delightful meeting of science and science fiction.

While you're at it, if you want a brief, non-technical look at some funky physics, read his old Analog columns. I'm very fond of the space drives. One article involves some work by James Woodward of Cal State Fullerton, whose site is well worth a look. Lots of material there on Mach's Principle, radiation reactions, and radical timelessness, of which I am a particular fan. Another of Cramer's columns describes a variation on the Alcubierre 'warp drive' which involves creating a bubble of spacetime bigger on the inside than it is on the outside.