Replies to This Discussion

Permalink Reply by Chris Crawford on March 15, 2013 at 4:18pm

I have great skepticism about this, tempered by the fact that my appreciation of GR leaves much to be desired. It strikes me as too close to a free lunch to be plausible. Still, I'll confess that I haven't figured out how it might violate Second Thermo or QM, so I can't yet declare it impossible. Just very dubious.

Permalink Reply by John Jubinsky on March 15, 2013 at 5:17pm

One of my favorite quotes by Darwin is: "Ignorance more frequently begets confidence than does knowledge. It is those who know little, and not those who know much, who so positively assert that this or that problem will never be solved by science." As such I can't hold that we will never overcome what appears to be the impossibility of FTL travel.

 

For example, Einstein said there were wormholes in the universe through which something could go to, in short order, get from one point to another light years away. Given this, I can't rule out that we might some day master a technology that enables us to create and travel through wormholes to quickly go great distances in the universe. However, I can't say I see it as happening in the very near future.

 

Nonetheless, I'm glad somebody is working on FTL travel and I certainly wouldn't laugh at anybody who was.

 

Technology develops exponentially. The more technology that is acquired the faster it develops. For example, we didn't even have the tricycle until 1680 and it took us almost another 200 years to develop the bicycle. Now by comparison look back 200 years and contrast the technology we had then to what we have now. Clearly, the amount of technology we developed in the last 200 years is exponentially greater than the amount we developed in the 200 year period before that. Accordingly, although I don't see FTL travel in the very near future, with exponential growth in technology, it might be developed a lot faster than I and most people are imagining.

 

With this in mind I wouldn't rule out that there are species in the universe that have already developed it. With exponential growth in technology consider what a species might have developed that had a billion years more than ours to develop. Assuming that it didn't blow itself away it might be quite advanced.

Permalink Reply by Luara on March 15, 2013 at 7:43pm

This needs a lot of negative mass-energy, shaped in a particular way.  They mention the Casimir effect as a source of negative mass-energy, however the Casimir force measured in labs is very tiny. 

So it's slightly impractical. 

So it's still possible there are aliens in our galaxy but not peeking into our windows at night. 

Permalink Reply by Chris Crawford on March 15, 2013 at 8:54pm

Let's differentiate between what is technically feasible and what is scientifically feasible. First we must establish that something is scientifically feasible, THEN we can argue over whether it's technically feasible. We have not yet established that it is scientifically feasible. Until that happens, we cannot apply the history of technological advances to this problem.

Permalink Reply by John Jubinsky on March 16, 2013 at 3:49pm

I'm talking about going FTL by traveling through wormholes. Einstein said things could travel through wormholes. Doing so might get something from point A to point B FTL. Sometimes we have to be careful not to throw the baby out with the bath water. Although wormhole travel might indeed be scientifically unfeasible I don't think we know enough at this point in time to definitively say it is.    

Permalink Reply by Chris Crawford on March 16, 2013 at 4:57pm

Yes, we can't rule out the possibility. The trick is that a wormhole requires that some equations have complex number results: square root of minus one. That's not part of the real universe, and that's the primary problem. Because of that, I think that the best overall assessment is, "Probably impossible, but worth looking into just to make sure."

Permalink Reply by Humble Pie on March 16, 2013 at 8:54am

I wonder if Alcubierre or White ever read "Inherit the Stars".  :)