Resolves as YES if there is strong evidence that an operational passenger vactrain provides service between Paris and London before January 1st 2070.
Paris connections:
/Dulaman/parislondon-vactrain-by-2070 (this question)
/Dulaman/romeparis-vactrain-by-2070
/Dulaman/parisberlin-vactrain-by-2070
London connections:
/Dulaman/parislondon-vactrain-by-2070 (this question)
/Dulaman/londonnyc-vactrain-by-2070
To count, all of the following must be true:
Operational passenger service (not a stunt): The system must carry paying passengers (or passengers traveling under a publicly offered ticketing program) from the Paris terminal to the London terminal, and it must do so on at least two separate calendar days (to rule out a one‑off ceremonial ride).
Paris endpoint: A passenger terminal/station located within Paris greater metropolitan area.
London endpoint: A passenger terminal/station located within London greater metropolitan area.
One continuous fixed guideway: The passenger trip must be possible on a continuous, fixed, physical guideway (tube/tunnel/structure). It cannot rely on aircraft, ships, or an “open ocean” segment.
Vactrain requirement: The core vehicle must travel inside a sealed tube explicitly described by the operator/regulators/credible technical coverage as low‑pressure / near‑vacuum for the transatlantic portion (i.e., it’s not simply high‑speed rail in open air). For the purposes of this question, the average air pressure surrounding the vehicule over the duration of the journey must not exceed 0.1 bar.
Direct Paris ↔ London passenger journey: The service may include intermediate stops, but passengers must be able to travel from Paris to London as a single offered journey without switching to a different transportation mode.
“Strong evidence” means at least two independent, reputable sources (e.g., major news outlets, national transport regulators, or official operator documentation with corroborating third‑party reporting) clearly indicate the above criteria were met before the deadline.
Resolves as NO if the above does not occur before January 1st 2070, including if:
only cargo service exists,
only test runs occur,
a system operates but does not reach both endpoint cities as defined,
or the first qualifying passenger operation begins on/after January 1st 2070.
1,000It's important to remember that new high speed trains are typically added to improve network capacity, not just reduce travel times. If you just want to reduce travel times, you can add direct services to more destinations to reduce the time people spend transferring. That's way cheaper than building a brand new permanent way, which has been proposed for the cross-channel route.
Will there be any demand for more Paris-London capacity? Certainly not. The Chunnel has a theoretical capacity of like 1,000 to 1,200 trains per day. They are currently using half that, and most of it is for freight. The passenger trains that are used are single-deck, but you could double the number of passengers by using double deck trains instead (which is already planned, but to reduce operational costs rather than to add capacity).
The only route where a vactrain makes sense to me would be Washington to Boston. That route already needs a new permanent way because the existing one is so poorly laid out and it's extremely capacity limited.