In reply to David Roberson's message of Sun, 30 Nov 2014 02:48:09 -0500: Hi Dave, >Robin, don't beat yourself up too badly about having a short term mental block >since it happens to all of us.
:) [snip] >We started this discussion considering the operation of UFO type devices as an >example. I have a difficult time accepting the fact that they might >actually be controlled by something not human. That concept seems to be too >fantastic to believe but I hope to realize the truth one day. ? > >The observation that these crafts appear to hover in the air silently and >without emitting any form of exhaust leads some to consider reactionless >drives as the source of the force that keeps them airborne. I do not feel >that this is necessary since the earth could easily form the other side of the >thrust equation. If the ship has some means of pushing against the earth, >then it would be able to balance out the momentum and energy equations that >have precipitated the recent discussion. I agree, it's not necessary, but may still be the case. One of the patents recently mentioned here was talking about the Meissner effect. That would probably work if you could create a sufficiently large superconducting "bubble", though I still haven't figured out how to calculate the lifting capacity per unit volume (which I presume would also very depending on the local field strength of the Earth's magnetic field), or even if this is the right question. :( > >We know for instance that a loop of wire carrying a large AC current can be >repelled by any nearby metal surface. The amount of radiation exiting that >wire can be quite small if the drive is at a low AC frequency. The near field >effects induce a current within the metal surface that generates a force that >holds up the loop. A power source on board the loop driven ship could be used >to supply the current that allows the device to float above the metal surface. AFAIK this works by inducing eddy current in the metal plate which automatically oppose the inducing field. However the Earth wouldn't appear to be a very good "metal plate"? > >Now, back to the UFO and Earth situation. An observer on the Earth might not >see the complete picture and could well assume that the ship emits no exhaust >or mass of any kind. Of course we know that the Earth is being repelled away >from the ship and supplies that mass. Momentum is conserved and all of the >energy can likely be accounted for. I say likely since I have not taken the >time required to prove it although I would be surprised to find out otherwise. Indeed. > >I of course have serious doubts that a simple magnetic drive would actually >generate the force required to keep one of those crafts afloat, but the >concept of using the Earth as the other side of the thrust equation might work >with another force. A method of manipulating gravity appears like the ideal >solution. > >Dave ...and would also work for the Sun, if it works for the Earth, or even the galaxy as a whole, or in part (IOW there is some form of gravitational field everywhere). However I suspect that even such a drive would not be used for long distance interstellar travel, because the relativistic aging would cause a real problem. Can you imagine returning home only to discover that your entire mission has been lost in the sands of time? That why I think that travel over any truly large distances would need to use wormholes. (Of course a light speed trip to Alpha Centauri would be interesting) ;) I also think that shielding would be a problem at speeds approaching that of light. A small rock in interstellar space could destroy the entire craft at that speed. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
