From the article: "If the idea is viable and the people behind it are competent, it should have attracted private investment, as there should be a potential to make profit selling the technology. After all, the proposal has been around for 23 years."
High speed rail on a large scale is really something that has to come from the government. While there are small private HSR projects (e.x. Brightline, covering some 60 miles of the Florida coast), the big successes have all been governmental, and that shouldn't be surprising.
The uncomfortable part of HSR, of course, is that no matter how perfect your government is, it's going to involve bulldozing some people's homes, conflicting with other government projects, and interfering with nature. Don't get me wrong, I'm not part of team "screw the law, bulldoze straight lines between cities, people and nature be damned". But there do need to be sacrifices made. And a strong, coordinated government can pass the laws and write the checks to make that happen.
The interesting thing with HSR is that it is not about the technology. The TGV was operating at 300 km/h nearly 50 years ago, and that's the speed that most of the network operates at today. It's not about the safety (the TGV has never had a fatal accident in normal service) or even the cost (the TGV is also profitable!)
It's about the land. A fairly small strip of land in a straight line. My hope is that as people realize this, we'll do what has to be done and tear down a few villages in order to save the planet. But that's politically unpalatable, so instead we have Gadgetbahnen.
[0] https://en.wikipedia.org/wiki/File:SNCF_BB_9004_photo_1.JPG
[1] Side note: that bit from Bordeaux to Irun is quite possibly my favorite train line in the world. Absolutely beautiful views towards the Irun end.
For comparison, a tgv test run in 2007 got up to 575km/h on fancy new track, also with some prep but no damage, but operating at this speed would make little economic sense at this point.
Even better, this steam-powered train, reaching 126 mph (203 km/h) in year 1938! [0]
Why do I know about this? Because I played Railroad Tycoon as a teenager in ~1990, and got fascinated by trains.
[0]: https://en.wikipedia.org/wiki/LNER_Class_A4_4468_Mallard
> "If the idea is viable and the people behind it are competent, it should have attracted private investment, as there should be a potential to make profit selling the technology. After all, the proposal has been around for 23 years."
They are referring specifically to the development of the technology I.E. the trains and rail equipment. Not to an actual infrastructure project.
The argument being that governments should find the infrastructure, and buy technologies developed using private funds.
Indeed this what we see in the rail industry where companies like Siemens develop rail “packages” which are then sold to multiple infrastructure projects with only minor customisation and modifications.
This is in contrast to the example project where a team wanted $250mil to develop new technologies, and also deploy them. Rather than just deploying an already developed technology.
TGV and Shinkansen go really far! But what makes people in France or Japan take the train a lot is much more around local trains that are just going at normal speeds.
Maybe in cities the wind is an issue.
It's worth pointing out that since the 1950s the government has been doing just that and more to build the vast network of interstate highways and state roads. People don't bat an eyelash at demolishing nature for a monster interchange, but propose more rail and suddenly it's so important to consider the environmental impacts and the eminent domain issues.
The I710 expansion, for example, was finally axed a few years ago after six decades of opposition from South Pasadena and the surrounding cities. At one point the state was considering a plan to tunnel under the town for about a $billion a mile because the opposition was so intractable (well funded and connected) before Caltrans gave up and started selling all the housing they'd been accumulating for decades for the project.
Correct me if I’m wrong, but my impression is that this is only true if one excludes the capital costs associated with the railroad (tracks, right of way, and I think also rolling stock). If you factor in the infrastructure construction costs (and reasonable lifetimes for replacing rolling stock), a high speed trail line will never be profitable without significantly higher fare prices than are presently charged.
But that goes to further support your point that high speed rail can only be accomplished with government input.
To be fair, I think that the same argument can be made for the costs of interstate highway systems and passenger air travel.
Figures for the profitability of the individual lines, with construction costs included, can be found here [0] in French. You'll see several lines with yearly rates of return in the ~7-15% range depending on how you measure things. I'd call that excellent, especially given that there are other massive benefits (environmental, health, safety, national security etc) involved that are not included in that calculation.
That said, I may be forgetting to include something, so I may be wrong. But, like you said, only further supports the point that high speed rail can only be accomplished with government input :)
[0] http://geoconfluences.ens-lyon.fr/informations-scientifiques...
Supposedly some subways (eg Hong Kong?) own the land near the stations and use the rents to fund the subway, rather than just using fares.
A land value tax that goes back into public transit would probably work too.
Here's one, just follow the links to the group companies.
The same was true for streetcars in the USA, many streetcar companies built amusement parks in the countryside at the end of their lines to encourage weekend trips.
So high speed rail in California is always going to be a boondoggle.
And just look at what we put next to our Bart stations: giant parking structures. Sigh.
here's why i think they get customers. people don't like airports and plane travel, so they'll pay more for rail. car travel is unpleasant. cars are tiny and uncomfortable. their tolls are insane. like $50 in tolls for that same drive. less people have cars, and getting an license is a big expensive thing. they don't do roadtrips.
We learned about this in highschool history.
From wikipedia:
The Pacific Railroad Acts of 1862 were a series of acts of Congress that promoted the construction of a "transcontinental railroad" (the Pacific Railroad) in the United States through authorizing the issuance of government bonds and the grants of land to railroad companies.
https://en.wikipedia.org/wiki/Pacific_Railroad_Acts
All transportation is subsidized by government. Great investment; I'm completely on board. With the understanding that owners and operators pay back via taxes. (Whatever is fair, something modest.)
It seems that the tunneling was meant to solve this in urban areas. Open farmland is easier to manage, perhaps leasing the strip from the owners, gaining right-of-way over roadways by working with local governments.
[0] Elon Musk's "Loop" - It's bad, folks https://youtu.be/4dn6ZVpJLxs
[1]https://www.redlettermedia.com/plinkett-reviews/mr-plinketts...
1) Bury the lines. Basically isothermal at depth.
2) insulate the tube and maintain stable temperature
3) use materials that don’t drastically change length with temperature
3) allow the tubes to change length. Put them on rollers.
4) use vacuum expansion joints just like us common in vacuum engineering.
People act like vacuum is this new thing. Physicists (well, Engineers/technicians hired by physics projects) have been making really long tubes with extremely high vacuum and incredibly high tolerances. This is easy in comparison.
Burying the lines would already make it an order of magnitude more expensive than what was promised. And now you have to compensate for ground movements, since your tube is fat and hundreds of kilometers in length, which makes it even more expensive.
Insulating the tubes to maintain temperature would be incredibly costly, and if there ever was a failure or natural disaster that prevented you from keeping up the power need, your tube will break.
Materials that have such little temperature change coefficients are much too expensive to build a 600km long multiple meter wide tube with.
If you allow the tubes to change length, your stations will move, sometimes in unpredictable directions. You also risk gigantic stresses caused by temperature differentials causing bending forces.
Vacuum expansion joints of that scale, for such a length, with such reliability are literally unheard of. And would likely be insanely expensive.
2) Kaa-ching! Both upfront and ongoing.
3) Kaa-ching! There is reason materials such as Invar are not found in railways, and cost is only one of them.
4) There is no precedent to using vacuum seals at that scale (or maintaining vacuum in that sort of volume).
Elon Musk just says "let it be suspended on roller supports so the terminals slide dozens of meters". Nothing wrong with that surely.
First of all: trains are great, there are many places where they perform admirably. Many cities have a great subway network, countries like France, Japan, Taiwan and now China have great high speed reail networks. So if there are transportation problems to solve, it should be a no-brainer to consider traditional train systems first.
However, there are shortcomings wiht traditional train systems, these new systems try to address. One big limitation for trains is, where to put the tracks. Inside cities, going underground usually is the only solution. With traditional rail, this is extremely expensive and also a slow process. In Munich, not log ago the digging for a new underground train line started - it is expected to take a whole decade and going to be quite expensive (which has delayed the project by another decade, as people were discussing costs). Outside of cities, rail is possible, but still faces problems to get the necessary ground. Noise is a further problems with trains. Finally, most traditional train systems are not operated autonomusly, so costs are too high for high frequencies and often enough there are just not enough drivers available.
These shortcomings create a lot of creativity to address them. The Boring companie tries to lower tunnel costs by making them less in diameter. Other systems try carts which run on or hang from stilts, reducing the space needed or allowing the train installations to go on top of existing roads.
Maglevs are still a huge topic. On the one side, they do allow higher speeds, as rails get mechanically challenging above 300kph. The only challenge for maglev is air resistance, there is no risk of derailing. Also, at any speed, maglevs are less noisy than rails, they can accelerate faster than rail and most importanly, go up much higher inclines. Maglev is therefore not only interesting for long-distance transportation, but also inside city regions, especially due to the lower noise and also because of autonomous operations. A good example is this maglev system: https://transportsystemboegl.com/ It is designed for city regions, fully autonomous and not just some technology concept, but ready-to-buy. It has been developed by a major construction company. That means, they won't just sell you some fancy technology, they are going to build the whole infrastructure for you ready to use. This is one of the two companies responsible for the quick building process at the Tesla Giga Berlin factory. They are basically factory producing the parts for industrial buildings and just assembling them on-site. (Ironically Volkswagen is also building a new factory for electric cars in Bremen, Germany at the moment and it looks exactly like what Tesla is building, as they ordered the factory from the same company)
Which is one of the main points of the article: the limiting factor is not the type of propulsion, but how and where to put the tracks.
Tunneling is expensive. Decreasing tunnel diameter just turns one knob of that system. Emergency access, switching and mergeing systems, and access to the tunnel itself use space and cost money. And if the idea is to just add tunnels to increase capacity, then that is probably more expense than building a proper train system with higher passenger density in the first place.
Trains that hang from stilts still need the stilts to sit on the ground somewhere.
Trains that sit atop of roads are limitied in their speed, by the traffic these roads where originally designed for. The curves might not be suitable to go around at high speeds.
You can't also just increase speed - acceleration and deceleration forces as well as the forces acting on a whatever kind of pod on whatever kind of track are physical limitations that affect passenger safety and comfort.
All these ideas improve on some small aspect of the system as a whole, but they do not solve the fundamental difficulties inherent in designing public transportation - they do the job, but not without the same real world problems that we have with traditional rail.
Autonomous operation for increased frequency might make some sense, but then that's something that can probably be retro-fitted to existing systems, and has little to do with the propulsion system in use.
... and I know of at least one urban public transport system where the limiting factor for increased frequency is ( apart from the issue that six train lines share one bottleneck track ) the time the doors take to close safely... not something I would have had on my radar as being a problem.
Making train tunnels cheaper by making them smaller is not a new idea. it is a very old idea. Have a look at the deep level tube lines of the London underground. In some ways, we regret having trains that small since it reduces capacity and makes it nigh impossible to air condition.
It's possible to make normal trains go over existing roads, elevated rail is also a very old thing, a lot of it did get taken down though.
Also if you want small trains, just look at the UK. Normal trains here are much narrower than normal US trains, they are about as wide as modern trams! And the London underground has trains that are tiny and shaped to make the most out of circular tunnels.
You don't need to rethink the entire system for the points you've raised there...
That is it's design. That is exactly what Elon is doing.
You might argue it can't do what it's setting out to achieve, but this has never been a technological solution.
He's designed a technology to fit with current societal processes rather than the old, get society to accept a technology.
They’ve developed a new machine, Prufroc, that’s supposed to be much faster and capable of “porpoising” (ie angling back up and curving straight) so you can avoid having to excavate a deep station through other means.
If they can get the cost equivalent to a typical surface street in urban areas, they can now compete with surface streets. Much easier to autonomously drive in purpose-built tunnels. Or put a train or a bike trail or moving walkway or whatever.
So they are actually trying to solve the right problem. And using cars is a good idea because cars are really cheap per passenger in terms of upfront capital cost, and they meet the speed, autonomy, safety, and electrification requirements while also allowing use on just regular paved surfaces. If the one-dimensional autonomy works well, they might be able to reduce follow distance at speed enough to exceed a highway lane throughout. And with high occupancy, also a typical light rail train or whatever.
Would be kind of neat to have autonomous driving at 120mph immune to weather and with low enough capital cost that we could afford to crisscross the country with them, without much impact to existing land uses. A clear win if it works. Actually, a clearer win than full autonomous driving on existing roads, as that might quickly clog up surface streets. Plus this is probably technically easier than perfected level 5 autonomy which is still a sort of open ended problem.
Do you mean $10m per mile?
Congratulations, you’ve rediscovered the subway.
If Musk wants to make the argument that he’s found a way to drastically reduce subway construction cost, I’m all ears. But he should jump straight to that, rather than this ludicrous idea of zipping personal cars around under the streets; a proposal that doesn’t come anywhere close to the transit density needed for an actual mass transit system.
Well, he does keep showing renderings of public transit stations full of Teslas and not, you know, people. It's not really a big leap to say that he doesn't understand when he keeps marketing as if he doesn't understand.
Turns out Teslas are cheaper per passenger seat than a subway car plus have less requirement for specialized infrastructure (rails, etc). So if TBC is gonna be doing the whole project, they intend to use Teslas. It’s not a bad engineering choice. With automation (not hard in a tunnel), can achieve similar throughput as a Subway.
Minimum train space with pretty standard signaling can be as low as 90s. With modern moving block systems that can be pushed even lower. The tube trains have a seating capacity of around 250 people and 800 people can be standing. This gives a capacity of between 3 and 12 people per second.
How are you going to inject 1 car per second (to reach the lower level) into the tunnel in a safe way? And even if you could do it - Consider how huge the stations must be. They have to contain 100+ cars plus space to enter/exit them (couple seconds to come to a stop, 10s of seconds to leave the vehicle - with some people quicker than others -, 10s of seconds for other people to enter the vehicle, couple seconds to accelerate and synchronize to the flow..).
Folks who dismiss getting subway-like throughputs haven’t actually done the math.
Sub-2 second spacing is quite unlikely to be used, since stopping distance (with 0 reaction time, which is not too unreasonable with LIDAR/RADAR) dictates around 2s spacing between vehicles (1.9s at 100km/h for teslas I believe). And while humans might be fine with ignoring safety aspects computers can't and shouldn't.
Nevermind that building a subway-light vehicles (more similar to a people mover) is not really the same thing as using slightly-modified Teslas as subway replacement (which is what it seems they will be using for now)..
You know and own everything about the other process so you can match them far better.
This is what Elon does. Hacks processes, not technology.
How is this something that can be solved with the yet to be invented new TBM?
From your link -
"The "ad infernum" theory positing property ownership "to the center of the Earth" has also been eroded. A review of modern American jurisprudence demonstrates that the theory is more poetic hyperbole than binding law, and that broadly speaking, the deeper the disputed region, the less likely courts are to recognize that the surface owner holds subsurface title. [21] Appraisal studies of subsurface projects such as subways, deep storm drainage tunnels, and particle colliders consistently conclude that such projects, built well below the area that the vast majority of surface property owners ever put to use, do not deprive the surface owners of any value."
> She says the pipes could come up on state-owned land beside motorways or (where they exist) railways.
No time or planning should go into surface hyperloops. These things belong underground. 100x better.
If you're above ground you'd just pop an emergency hatch in the tube.
You can't do that underground.
I'd also point out that a hyperloop tunnel is a much worse place to be stuck in than a normal tunnel.
In a normal tunnel there is room to walk alongside the tracks.
In a hyperloop tunnel there is virtually no room between the car and tunnel - maybe an inch or two, tops.
This also applies to any sort of failure that compromises the vacuum. A dipshit with a rifle could kill anybody in the system in a fraction of a second. Burying the tubes is probably the only way to avoid this, but thankfully the whole thing is vaporware anyway.
Humans can survive (uncomfortably) at .5 atm and you eliminate the vacuum cannon problem simply by putting pressurization valves periodically throughout the tube.
I am not sure what do you mean by 'ubes are not air tight and actually breathe', but they definitely are not air permeable.
I'm just extrapolating from trends and some cherrypicking. The ongoing elevated rail project in Hawai'i is now running at $500M per mile. Boring Company projects they can get cost of tunneling down to $10M per mile.
What I forecast (without much data, so please correct me if I'm wrong) is that with more money going to tunnels, we will see the costs continue to drop. You don't have the quasi-extortion that goes on now over land rights above ground.
Tunnels also scale better long term—you can just keep adding tunnels.
But beyond cost and scale tunnels are just so much nicer. You can replace ugly, polluting above ground infra with parks and greenery. Even though the Big Dig in Boston took forever and went way over costs, the city is so much nicer now without the Central Artery.
Note that you're (or, rather, Elon Musk is) comparing apples and oranges. Tunnels are actually cheap, about $80m / mile. The expensive parts of metro systems is not the tunnels, but the things that go inside them and stations. This is doubly so for the inexcusably high costs of US transport construction. When people talk about the cost of metro systems, the divide the total cost of the expansion (or entire system if it's a new one) by the length of the system, so they include the amortized costs of new vehicles, infrastructure inside the tunnels, and stations (which often cost more than the tunnel to get to them! Station excavation isn't cheap).
Also, all the materials used on the Hawaii rail line have to be shipped in - literally, adding expense.
China builds a mile of track at half the price because they literally pay their people half the price (or less). It doesn't matter that their local Purchase Power might be greater.
Taking it a step further, the Parent was comparing a mile of track in China to a mile of track in Hawaii, which literally has to ship all supplies, and likely a lot of labor, across an ocean. So it's not a great comparison even if we remove labor costs.
In practice, laws are not always followed to the letter, but the same can be said in the US. You have the right to appeal to higher court, which is effective as unless it is a hugely major project, expropriations are generally made by the municipal or regional government.
As for environmental studies, they are directly paid for by the government. Environmental standards obviously vary, but have been strongly strengthened in the recent push against pollution.
It matters because it means that the economies are not directly comparable.
You said they can only do that "without paying US prevailing market wages to the contractors." as if that is somehow an unfair advantage. But if their workers don't need US salaries to have a good living standard, because purchasing power is higher, and are not being exploited, where does the problem actually lie?
Melbourne to Sydney always seemed like a good choice to me. It's one of the busiest air routes in the world[1], there is obviously tons of solar, lots of open land beside the existing road, no seismic activity to speak of and it's a good long distance to get up to speed (~1000km).
[1] (actually #3 in the world by number of passengers) https://en.wikipedia.org/wiki/List_of_busiest_passenger_air_...
Then you can just build a conventional 300kph high speed train and track. They are 'off the shelf' commodities these days.
It will still be competitive with flying.
Flight time is 1 hr 20 mins.
At 300kph it's going to take a high-speed train almost 3 hours.
And frankly not being subjected to the TSA is generally worth at least a few hours of my time. I'll sooner drive six hours than fly one because of those worthless assholes.
The damage from earthquakes tends to be a ripple of the ground in the first few meters and that’s it.
This isn't to say that engineering around these sorts of events is impossible. The Transalaksa oil pipeline crosses the Denali fault, and during the M7.9 Denali earthquake in 2002, the pipeline survived because it was built on sliders near the fault so it would bend when the earth shifted instead of breaking [3]. However, this is a big bend in the pipe; the lateral displacements are on the order of 5-10 m in an earthquake of this size, over a similar across-fault distance. Do you want to go at Hyperloop velocities through a tube with a bend this sharp?
[1]: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.833...
[2]: https://www.usgs.gov/media/images/modified-mercalli-intensit...
I disagree with your conclusion. Hyperloop technology is so lucrative that it might galvanize America to update its long distance transportation infrastructure in a way that bullet trains couldn't have.
Bullet trains:
- Popularized when a huge network of new highways and slow rail were already built in America
- Faced a suburban, car-loving culture
Hyperloop:
- 2-3x speed of bullet trains. Can change the way we perceive geographic distance.
- Popularized during an increasingly urban culture with crumbling highway and train infrastructure
- Cost isn't as much of a concern because a national hyperloop network would create a lot more value than a bullet train equivalent. If the government doesn't want to shoulder the full cost, companies gladly will (when the tech is ripe). I'm hoping for full government funding.
What is the basis for such claim? Most of the information I come across points in the opposite direction.
Trains are a lot cheaper infrastructure wise, and have ~10x higher capacity. Many public transport infrastructure professionals consider hyperloop a joke because it can only move a fairly small amount of people. In UK we are running out of capacity on many rail lines.
So why do you believe hyperloop would generate more revenue or indirect economic benefits compared to a modern high-speed rail?
> - Cost isn't as much of a concern because a national hyperloop network would create a lot more value than a bullet train equivalent.
High speed brings with it some pretty severe problems. The most well-known is curve geometry: curve radii scale with the square of velocity. Transition track (how long the "S" of a S bend needs to be) scales with the cube. But it's not the only issue. Also scaling quadratically with speed is energy consumption and stopping distance. Speed only gives you a linear improvement in time, so things like capacity decreases [1] and stop penalties are only linear.
But the difficulty you face is switches. Here, you have curve radii constraints, which means your problems are in the quadratic issue. I've never seen any depiction of a hyperloop switch [2], but I imagine it's going to be more in the vein of move the entire tube than just swap a point. In any case, a high-speed switch capable of being traversed at 200 km/h is... 164m long. To go 1000 km/h would require it to be 4.1km. That means it will take a vehicle at least 14.76s to traverse it. So you can't schedule vehicles any tighter than that, but for safety reasons, you want the following vehicle to be able to come to a complete stop in case the switch breaks down before it can complete moving--which is going to slow you down to minutes between vehicles [3].
With these constraints, you might think people would be trying to design high-capacity vehicles, competing with the ~1000 you can stick on a normal trainset. But the design is more akin to a small airplane with the wings and tail cut off, fitting maybe a few dozen people per pod. Actually, the more you look at the designs, the more you see airport-style operational motifs sinking in. It starts to look a lot more like a long chain of point-to-point links, with the capacity issue of airplanes, but the infrastructural cost of railroads. Even the modelling seems to basically assume that people will treat hyperloops as airplanes.
[1] Yes, making a train network higher speed decreases its total throughput.
[2] A telling sign in itself.
[3] The highest capacity metro systems today can manage to schedule 45 trains per hour, and most systems are typically about 25 trains per hour. I believe the highest capacity HSR line is 6 trains per hour.
Smartrail and PRT are designed as a point to point separated-grade network carrying on av. 1 person or a pallette of goods. With a hanging rail you don't need heavy batteries, parking for the vehicles, you can run a pod straight into the factory to pickup goods, and large/rich places can pay to have track straight to their door.
You can prefab the rail and as land usage is just poles in the ground it can be rolled out over fields etc quickly. Track is one-way to eliminate junctions. Pods are on-demand ie. No waiting.
Accessibility improves, you can use the top of the rail to generate (solar) power, run highspeed internet cables in the rail to improve comms across a country, and save on distribution center logistics as you're going point to point.
The last mile may possibly be an issue, but forklift drones and bicycles can take most of the load I feel.
Drivers for this are that it would go fast (200mph+ as light pods so little wear), can go overnight (sleeper pods), you could buy track to your door, personal transport (like a cinema room if you want). The main real issue with cars is that there's a large lobby behind what is a legacy transport solution...
By way of example, UltraPRT has been running flawlessly at Heathrow airport for 10 years, was built on time, on budget, and performs exactly as predicted/modelled.
For more info checkout http://faculty.washington.edu/jbs/itrans/ in particular Swedetrack (https://web.archive.org/web/20060202013014/http://www.swedet...)
As for the curvature issue, there seem to be a couple ways around that. One is to straighten the route to the maximum extent possible (not trivial but not impossible for some routes). The other is to build massive curves and decelerate into them. Again, there are tradeoffs (cost,speed) but it's not impossible. There are just so many variables. A hyperloop could end up being great for some areas and unworkable in others.
Lastly, right of way/land clearance should never be a key constraint. That won't stop us if we really want to build a hyperloop.
Significantly increased costs
> and/or increasing the tube diameter?
Immeasurably increased costs. Because hyperloop already operates on the idea of operating in vacuum. So let's say you have a 10-kilometer tube that you need to keep in vacuum and you want to increase its diameter...
For example: There are 7 Shinkansen between Tokyo and Osaka tomorrow between 9am and 9:30am. That would mean 13 - 14 trains per hour.
At 3x of bullet trains speed a curve radius of 2500m resolves to 2g lateral acceleration.
For all purposes Hyperloop is very much like Theranos.
In the case of Musk's original proposal posed against HSR, largely because it had far fewer stations and because it had termini nowhere near the notional urban endpoint destinations, because getting close to them required high-priced right of way.
It basically was a way to get from the distant (in transit time from SF) fringes of the Bay Area to the, IIRC, even more distant (in transit time from LA) fringes of the LA Basin.
It seems to me that hyperloop is high speed rail with the addition of a vacuum, which gets you higher speed. The additional requirement of a giant vacuum tube should make the system cost more, not less.
Personally, I’m rooting for Elon Musk to figure out how to make tunnels cheaply with the Boring Company, so we can take that tech and use it to build a bunch of subways. Traffic within urban areas and suburbs is a much bigger societal issue than intercity travel anyway. Subways are a proven solution, but somehow we lost the ability to dig tunnels economically so we stopped building them.
A large amount of cost is in the stations.
In the us, a large amount of cost is inefficiency, projects cost much more than elsewhere, even considering purchasing power parities. Alon levy has written and talked about it extensively, e.g. https://pedestrianobservations.com/2019/03/03/why-american-c...
I don't know how as-actually-built hyperloop compares to rail tunnels.
This is what Tesla did by starting with the Tesla Roadster then Model S then Model 3... and it's what the Hyperloop aims to do. Launch as a small throughput luxury product and if it's profitable then it doesn't matter if it ever expands beyond that or not.
It is very much not.
Tunnels are used only when absolutely necessary to deal with terrain.
The problems with building this have nothing to do with technology but with right-of-way, investment, and politics. If those factors were solved, we'd already have high-speed rail in places where Hyperloop has been proposed. The fact that we don't says that Hyperloop is unlikely to be feasible as well.