A big reason why these ideas aren't being actively pursued is that they are conceptual ideas. They may have some detail and even some good speculative designs but ask any engineer if the path from paper-to-product is an easy 1:1 mapping and they'll laugh hysterically.
Whilst things like launch loops/beanstalks etc promise great efficiency and payloads over conventional rockets they would require a staggeringly high budget over a significant time to figure out how to build and then build. Rockets are perfectly adequate for our space needs and wants at the moment. There just isn't enough demand, economic or otherwise, to justify the expense of such a project.
On a separate note has there really been a decline in SF big ideas or has there been a decline in SF set in space? I've read various blog posts by SF authors in recent years on this issue and there have been changes in SF. I wonder if the disillusionment felt by authors and fans is because we are living in the future of past SF and the former makes the latter look quant and often silly.
Whilst things like launch loops/beanstalks etc promise great efficiency and payloads over conventional rockets they would require a staggeringly high budget over a significant time to figure out how to build and then build. Rockets are perfectly adequate for our space needs and wants at the moment. There just isn't enough demand, economic or otherwise, to justify the expense of such a project.
On a separate note has there really been a decline in SF big ideas or has there been a decline in SF set in space? I've read various blog posts by SF authors in recent years on this issue and there have been changes in SF. I wonder if the disillusionment felt by authors and fans is because we are living in the future of past SF and the former makes the latter look quant and often silly.