Perhaps a stupid question, but the shock wave forms because the trains is moving continuously over the ground? So if you put the entire thing on stilts, there would be one wave formed at t0, x0 when the train reaches pylon 0 and the next wave would be at t1, x1 etc. So the interference pattern for the waves would look vastly different. ( This holds of course only for point like trains... )

A test segment would go a long way to determining if/how much of a problem this might be in a hyperloop system.

Putting the railway or tubes on pylons would give you an opportunity to dampen or otherwise transform those vibrations wouldn't they?

Maybe, maybe not. Guideway supports (pylons) are typically founded into the bedrock which does reduce vibration somewhat, but the vertical motion of the pylon moving against the soil will still generate shear waves.

This is why a demonstration project would be useful.

Passive resilient systems could help with higher frequency vibration (above say 100 Hz or so, depending on the forces and weights involved), but for lower frequency vibration (especially below 20 Hz), the resilient elements would have to be so compliant that even a gentle breeze would create very high vibrations in the guideway itself, which would be incompatible with the speeds of the cars inside.

You could make the pylons so massive that the forces from the vehicles couldn't move it, but again you're talking about higher construction and material costs, as well as visual impacts.

edit: though, mind you, the whole capsule also has mechanical suspension

Musk has already given more than enough for the world and done more than enough. Somebody should do it, but we should not expect him to do it.

True innovators carry all of humanity on their backs, and give massively to all of humanity, present and future.

The fact that they get some monetary compensation doesn't entitle you to not be grateful and to not recognize their heroism.

It does not entitle you to imply, as you have, that they deserve the same level of praise as any person who is paid for any work whatsoever.

You are, by implication, equating Elon Musk to the teenager flipping burgers, or any other menial laboror.

That is moral treason.

Without innovators, we would all be dying in pestilence-ridden Stone Age villages. In my opinion, those who claim that innovators do not deserve the highest of possible praise _deserve_ that fate.

Musk would have a hard time innovating if he had to build his own house, grow his own food, knit his own clothes, etc. etc...

We all rely on each other to provide our basic standards of living.

Without our basic needs being satisfied, we don't have a platform from which to focus on innovation.

Yes, innovation is great, but don't act like they are the entire backbone of humanity.

If you were to calculate the sum of gains and losses between Elon Musk and humanity, it would balance out that Elon Musk is overwhelmingly the creditor, and humanity is overwhelmingly the debtor.

As with the great-grandparent of this comment, your comment is a massive moral equivocation.

Specifically, an affordable Tesla car could benefit the entire world, whereas the Hyperloop would (at least initially) only benefit people living in LA and SF.

They both have the potential to be hugely beneficial to the entire world. Although in Tesla's case it's more of a certainty... fortunately we can have both :-)