101–110 of 146 posts
Wouldn't transporting humans at 2,500 - 4,000 mph kill them? It seems like the body would not react well to beginning or ending transit at such velocities.
I never have understood people's fears about getting on an airplane... this though I'd be scared to death of. You have any unfortunate shift in the tectonic plates (which happens daily and unpredictably) and you could be dead in an instant.
Here's how the Japanese high speed trains deal with earthquakes: They have emergency break systems (I think its small ceramic globuli or something of the sort) and a really good forewarning system. 2011-3-11 all Shinkansen were at a halt when the big one hit and noone was harmes on them. I don't see why you couldn't do the same here.
Good luck holding a vacuum under the ocean. I read stuff like this and I think, "Gee, I don't think these people have actually built anything." because if they had they would realize that if it costs $1M a foot too build subways [1] in cities with moderately skilled labor, its going to cost $10 - 25M/ft to build something like this. That's half a quadrillion dollars (448 trillion dollars). What sort or rate of return…
1988 $3.6 billion = ~$7 billion today[3].
1994 $21 billion = ~ $32 billion today[4].
Put it altogether, the tunnel itself would be around $3.5 trillion[5]. Maglev + vacuum stuff would cost more.
(BTW, I love WolframAlpha for stuff like this.)
[1] http://en.wikipedia.org/wiki/Seikan_Tunnel
[2] http://www.engineering.com/Library/ArticlesPage/tabid/85/Art...
[3] http://www.wolframalpha.com/input/?i=%24US3.6+billion+1988+d...
[4] http://www.wolframalpha.com/input/?i=%24US21+billion+1994+do...
[5] http://www.wolframalpha.com/input/?i=%28%28%2432+billion%29%...
Earlier quoted context omitted.
Indeed, there's already a vacuum we already have above our heads that could be used for this purpose... i.e., suborbital space flight. I can't imagine it'd be more expensive than tunneling 3000 miles under an ocean.
I doubt it is a tunnel. I imagine it'd be more like this: http://en.wikipedia.org/wiki/Immersed_tube (San Francisco's rail connection across the bay uses this technique)
Wouldn't transporting humans at 2,500 - 4,000 mph kill them? It seems like the body would not react well to beginning or ending transit at such velocities.
Acceleration is perceptible, because it is felt as a force. So it really depends on how quickly people are accelerated to 2500mph. If you accelerate at 22mph per second, this is equivalent to 1G, which could be relatively comfortable. It would take 2 minutes to reach 2500mph.
I live in NJ, about 4 miles away from my office in Manhattan and I have a 45 commute. Can anyone figure out how to solve that problem? It's a lot of fun to kill the afternoon talking about something that's never gonna happen. In the meantime, millions of people are wasting days a year crawling to and from work.
a. move your home closer to work
b. move work closer to your home
c. move both
Earlier quoted context omitted.
That is a great question, I wish I could reasonably answer it. I'm a big fan of rail, and while San Jose was celebrating their first 4 miles of light rail (in just 10 years from the start of the project!) I was looking that the marker in the Sacramento Rail museum (recommended) commemorating the laying of 10 miles of the Union Pacific rail line in one day . Part of it is that some folks really hate rail, so much so t…
Haven't you just proven that your initial post above is irrelevant to an undersea rail system? I'm not saying an undersea rail system is practical or smart. I'm just asking the relevance of your comparisons to US urban construction costs to begin with. As a suggestion, a different tone might make your post seem more useful and less trollish. For example "An undersea tunnel will require serious construction breakthrou…
My initial point is a prima facie argument, the proposal is impractical by inspection. I certainly stand by that assertion, but as part of the supporting argument we've been discussing land based construction with the implicit, albeit not as well supported, stipulation that sea based construction would always be more expensive than land based.
An interesting way to approach the problem would be to outline the design space in terms of operation cost, development cost, and rate of return and see what sort of solutions, if any, might fit inside that box.
Earlier quoted context omitted.
Haven't you just proven that your initial post above is irrelevant to an undersea rail system? I'm not saying an undersea rail system is practical or smart. I'm just asking the relevance of your comparisons to US urban construction costs to begin with. As a suggestion, a different tone might make your post seem more useful and less trollish. For example "An undersea tunnel will require serious construction breakthrou…
Great feedback, thanks. The conversation wandered a bit, and while I don't think of my style as trollish I can certainly see how my emotion on rail interferes with my communication. My initial point is a prima facie argument, the proposal is impractical by inspection. I certainly stand by that assertion, but as part of the supporting argument we've been discussing land based construction with the implicit, albeit not…
How can we get back to a society that is able to engage in large scale projects again? Look at the rapid low-cost subway construction in China today.
I think you're a super smart guy with really broad interests, experience, and knowledge. I think you could make the impossible happen if you applied yourself to it.
Earlier quoted context omitted.
Here's how the Japanese high speed trains deal with earthquakes: They have emergency break systems (I think its small ceramic globuli or something of the sort) and a really good forewarning system. 2011-3-11 all Shinkansen were at a halt when the big one hit and noone was harmes on them. I don't see why you couldn't do the same here.
Wouldn't emergency brakes pretty much kill you if you're traveling a few thousand mph at the time?