06-09-2015, 01:32 PM
I don't think there's really an issue with reversible computing producing a small amount of heat in and of itself. Although, the process probably isn't going to be perfect in reality, regardless of what may be possible in principle.
The biggest issue I'm seeing here is two-fold:
a) How much energy is going to be involved in intercepting and launching these 'rocks'. Unless you are willing to wait an extremely long time for your computer to get up and running, to take in new input, and to deliver results to the outside world, there is going to be some energy release involved in launching and catching them. Probably also in course corrections over the sort of distances you are proposing, although that would presumably be less of a factor over much smaller distances that could also potentially be used.
b) This system is going to be a lot slower than a conventional irreversible system using conventional cooling methods or even an reversible system using conventional data transmission methods and cooling to deal with the heat generated (I'm assuming that you haven't mentioned using optical or other EM based input/output systems that these are not reversible). Under most circumstances, it seems unlikely that users would be willing to wait for the months to years (or decades) it would take for information to be input/output from this kind of system. Also, it sounds like it would be limited in the types of computation it could do if the we're just talking 'a little new date mixed with a lot of old results or purely old results'.
Whatever performance pluses it would get from producing minimal heat via reversible computing would seem to be overwhelmed by the long wait times to input data or get useful results from it. That doesn't mean that no one would find a use for it (a group like the Backgrounders, who seek to minimize waste heat production might build something like this for some major computing effort, perhaps - they aren't generally bothered by long wait times anyway).
But generally speaking it sounds like the long wait times negate whatever benefit is to be gained by playing ones bit erasing processes at a distance and limiting oneself to portable data storage for input/output rather than using EM based methods. At least under most circumstances. And assuming this all works as advertised of course. I keep having this nasty concern that something is being missed here and that thermodynamics will somehow prevent this from working (the I/O bit, not the reversible computing bit).
So, generally speaking, if I'm understanding this correctly, it might have niche application within the setting, but I don't see an I/O system like this being widely used, because the costs outweigh the benefits in most cases. Reversible computing might have much wider application in the setting in places where waste heat needs to be minimized.
Todd
The biggest issue I'm seeing here is two-fold:
a) How much energy is going to be involved in intercepting and launching these 'rocks'. Unless you are willing to wait an extremely long time for your computer to get up and running, to take in new input, and to deliver results to the outside world, there is going to be some energy release involved in launching and catching them. Probably also in course corrections over the sort of distances you are proposing, although that would presumably be less of a factor over much smaller distances that could also potentially be used.
b) This system is going to be a lot slower than a conventional irreversible system using conventional cooling methods or even an reversible system using conventional data transmission methods and cooling to deal with the heat generated (I'm assuming that you haven't mentioned using optical or other EM based input/output systems that these are not reversible). Under most circumstances, it seems unlikely that users would be willing to wait for the months to years (or decades) it would take for information to be input/output from this kind of system. Also, it sounds like it would be limited in the types of computation it could do if the we're just talking 'a little new date mixed with a lot of old results or purely old results'.
Whatever performance pluses it would get from producing minimal heat via reversible computing would seem to be overwhelmed by the long wait times to input data or get useful results from it. That doesn't mean that no one would find a use for it (a group like the Backgrounders, who seek to minimize waste heat production might build something like this for some major computing effort, perhaps - they aren't generally bothered by long wait times anyway).
But generally speaking it sounds like the long wait times negate whatever benefit is to be gained by playing ones bit erasing processes at a distance and limiting oneself to portable data storage for input/output rather than using EM based methods. At least under most circumstances. And assuming this all works as advertised of course. I keep having this nasty concern that something is being missed here and that thermodynamics will somehow prevent this from working (the I/O bit, not the reversible computing bit).
So, generally speaking, if I'm understanding this correctly, it might have niche application within the setting, but I don't see an I/O system like this being widely used, because the costs outweigh the benefits in most cases. Reversible computing might have much wider application in the setting in places where waste heat needs to be minimized.
Todd