5 ms·
"b) promises reducing tunneling costs by a factor of 10, a feat that he himself has no chance to achieve, and c) is unaware that the cost reduction he promises,
by njarboe 9y ago
"b) promises reducing tunneling costs by a factor of 10, a feat that he himself has no chance to achieve, and
c) is unaware that the cost reduction he promises, relative to American construction costs, has already been achieved in a number of countries."
So Musk, a person who owns and is the CTO of a company that can now land reusable rockets that were only dreamed about in science fiction a decade ago, won't be able to drop tunneling costs in the US by a factor of ten, when the author admits this is already done in other countries.
Not sure this is worth reading past that part.
- hacknat 9y agoHe’s specifically calling out the goal of reducing tunneling costs by accelerating the TBM. The other projects that have reduced costs have done so through boring old sound construction management practices (the article pointing out the labor and stations are actually the expensive parts of these projects, not the tunnel by itself). Also, if you read the rest of the article he literally predicts your response of appealing to the authoritative win of SpaceX as a completely invalid counter argument (and he’d be right, appeals to authority is on the list of logical fallacies, last I checked ;) ).
- jakubp 9y agoOr perhaps the author of the article is doing armchair philosophy, whereas Elon Musk is the supposedly too optimistic doer who actually builds incredible stuff. (In the sense that Nassim Taleb distinguishes people who talk a lot and people accomplish stuff.)
- njarboe 9y agoOne can't prove a negative. The Boring company has a plan and a goal. Saying it can't be done is not useful or productive. There has not been much change in tunneling tech in the last 20 years and Musk seems to think it is possible to get some great improvements. He has done it in two other very different fields with SpaceX and Tesla. Creating a new technology is not about the logic of debates but doing things and failing over and over again, in a productive way, to get to success. Musk can access great people and large amounts of capital, thinks things out from first principles, doesn't believe in "safety first", and thinks tunnels could be of great value. Traffic (on car and trains) is killing our cities and nothing is being done about it. No new transportation infrastructure built in the Bay Area since 1980 except a few small BART extensions. We could put anything in these tunnels. Not sure why people are so worried that he is going to get some people together and try.
- andrewflnr 9y agoI'll grant TFA lacks imagination, but... One can't prove a negative. This meme needs to die. On HN, of all places, we should all know that the difference in difficulty between proving P and !P has nothing to do with one of them having a negation in its syntax.
- njarboe 9y agoI guess a better statement is that in complex systems one cannot predict what is possible. One can only try and see what is possible by doing. Most people here might be computer people so need to see the world in very precise, math like, constructs to produce code that works, but most of reality is not like that.
- bobthechef 9y agoTheorem. There are no even prime numbers greater than 2. Proof. Assume n > 2, 2 divides n and n is prime. Therefore, 2 is a prime factor of n. But since every prime number only has one prime factor, itself, then n = 2. But n = 2 contradicts n > 2. Therefore, no prime numbers greater than 2 exist. QED. - or - Claim. There is no beer in the fridge. Argument. I opened the fridge, there was no beer in the fridge. - or - p is a proposition. ~p is its negation. Take q = ~p. Proving p is the same as proving ~q. Seems to me you can most certainly prove "negatives".
- thephyber 9y ago> One can't prove a negative. Fine. One can't necessarily prove a negative. Only if you can prove the negation of the assertion can you "prove the negative". Now apply that logic to: <Musk> I can reduce the cost of boring by an order of magnitude. Can you prove that he can't? The gp was (over)simply stating that just because no other digging project has done what Musk claims to be able to do doesn't necessarily mean that Musk can't do it.
- deleted 9y ago[deleted]
- UncleEntity 9y ago> He’s specifically calling out the goal of reducing tunneling costs by accelerating the TBM. IDK, if they can make a boring machine that is faster and more efficient than the ones used on projects that achieved the cost/km they are shooting for I really don't see the problem. An automated (less labor), faster (less labor over the life of the project), smaller bore (less cost per mile) and more efficient (less cost per mile) machine should reasonably be able to hit the same target current technology already has, no? I'm also thinking there's probably a lot of low-hanging fruit to be found if one starts fresh instead of having to tie into an existing system or use the 18th century train model. It's not like shooting rockets to the moon or anything.
- eesmith 9y agoThe article argues that 1) the boring machine isn't the biggest cost, so if TBM speed were an important factor and you want faster digging now you can use multiple TBMs, 2) the current labor costs in the US is primarily a "political rather than technological problem", and 3) bore size doesn't have that much of an effect on overall cost. Indeed, "there’s a trend toward bigger tunnels, as a cost saving mechanism" as for example "[i]n Barcelona, the large-diameter TBM actually saved money and reduced disruption in construction." Shooting rockets at the moon is 1950s technology. ;)
- UncleEntity 9y ago> 1) the boring machine isn't the biggest cost, so if TBM speed were an important factor and you want faster digging now you can use multiple TBMs Yes but reducing the cost of something that "isn't the biggest cost" which directly effects the things that are the biggest cost does seem to be beneficial. > 2) the current labor costs in the US is primarily a "political rather than technological problem" Which is why a boring machine which reduces overall labor costs through increased efficiency and automation also seems to be beneficial. > 3) bore size doesn't have that much of an effect on overall cost "The Barcelona Line 9 doesn’t use the 12m diameter stacked tunnel along its whole route. Some sections are built using different construction methods, presumably because they are cheaper. This mostly depends on the local geography and available space."[0] "This is why there’s a trend toward bigger tunnels, as a cost saving mechanism: BART’s San Jose extension is studying different tunnel approaches, one with a large-diameter tunnel and one with twin small-diameter tunnels, and the cost turns out to be similar. " One could be excused to think 1 large tunnel == 2 small tunnels would imply that one small tunnel would cost about half of one large tunnel. As an aside, I grew up out there, why they even digging tunnels, not like there's a mountain between Fremont and SJ? Still not seeing a reason why it isn't possible to make digging tunnels efficient enough to...actually, why are we even arguing over how some rich dude choses to spend his money? [0]http://www.cat-bus.com/2017/10/barcelonas-line-9-inspiring-montreals-pink-line/ http://www.cat-bus.com/2017/10/barcelonas-line-9-inspiring-m...
- m3kw9 9y agoThe author is also noting Asia. Countries where labour costs, govt subsidies, currency cost, etc is superior. Comparing costs in US to another place is not a good comparison
- icegreentea2 9y agoI mean, his main argument is that costs that revolve around the TBM do not make up enough of the total cost of tunneling that TBM and tunnel diameter based cost savings can generate the costs savings that Musk wants to achieve. His primary data with regards to TBM and diameter costs comes from Europe (which ya, is not USA, but closer than Asian countries), and comes up with a rough upper bound of 50% of total tunneling costs in the LHC were associated with the TBM (this is bound to be lower for any transit application, that isn't a point to point tunnel due to additional group level access and extra boring). If TBM costs are 50% of total cost, no amount of TBM cost reduction can achieve the 90% cost reduction goal - it clearly has to be combined with other strategies. I believe it's clear that the author believes that these other strategies (all of which is probably project management based strategies) should be engaged with first, before falling down a path of throwing capital and R&D at cost reduction mechanisms (reduction of tunnel diameter for example) that may have significant technical and long-term short comings. I mean, the entire blog post is just telling Americans what Americans kind of know - Large American government contracts are often poorly managed and executed (for whatever reason), and that reaching for a technological magic bullet is unlikely to achieve what we want.
- functionsWorld 9y agoExactly where I ejected.
- maxxxxx 9y ago"can now land reusable rockets that were only dreamed about in science fiction a decade ago" You could have done that 40 years ago. SpaceX has figured out how to do this in an economically feasible way but technically it was possible a long time ago. Same for Mars. We could have landed there probably somewhere in the 1980s if someone had been willing to pay for it.
- njarboe 9y agoYes, it was possible but did not happen. Somebody(s) has to be the person/people that does it. Nuclear powered rocket engines existed in the 1960's, but little to no work has been done on that problem since then. If someone develops one in 2361, proclaiming, "not big deal, we could have done that four hundred years ago" is a bit silly. Musk went to NASA's website back in 2000 or so looking for the man to Mars plans and found nothing so he started a rocket company to bring down launch costs by a factor of 100. Ten years later reuse of rockets is happening. Amazing isn't it. Let's see what the next twenty bring.
- maxxxxx 9y agoI just don't think that anything SpaceX or Tesla have done is science fiction material the way you wrote. They are really good at commercializing and streamlining existing ideas and they have the courage to do something first.
- jryle70 9y agoWhy mentioning sci-fi can be a bit hyperbole, the fact is that rocket reusability was considered a pipe dream a decade ago. Nobody thought it could be done commercially. SpaceX sticked with it and prevailed in the face of all skepticism. It's just not "commercializing" and "streamlining" as you trivially dismissed
- njarboe 9y agoScience fiction is part of the spectrum of: Idea --> Actually Economically Viable Product. Your "existing ideas" is not very different from science fiction compared to the amount of work needed to get to viable product from existing ideas.