Being a SAD person it being light in the mornings I find helpful. It gets light at 7.30/8 at the moment and I ride to work without needing lights which is nice. For that very reason I wouldn't move much further north...

Point is they run to a schedule, usually the same throughout the year. Without the adjustment for summer time you would have different schedules if you wanted the benefit that summer time brings. Then people might change schedules at different times and it all gets very confusing. There is little economic or energy benefit but at 52 degrees north it does feel necessary.

Schools are also an issue, people tend to have to fit work around children. There are a bunch of good economic reasons why keeping to roughly the same clock is useful to many industries and personal schedules.

The sun rising after 9 here in a winter summer time is problematic, it would also set before 5. In the summer it would rise at 3.30 on GMT and set at 8.30. It makes sense here. It may not be saving any daylight but it does make it more available in summer and possible to see in the winter.

The sun is setting at 3.50 or so here at the moment. So it'll be dark at the end of the day regardless. The hour of light in the morning is useful in the winter, else it'd be rising at 9.10 and setting at 4.50 with winter 'summer time' (I'm British, it's British Summer Time not DST for us). I understand for those at lower latitudes it isn't obviously good. It's light 'til after 9pm in the summer with BST too. So I personally like the change.

Actually they can lend out $90 if you assume a 10% fractional system.

I am aware of this, but they got the stone from near a river and they built the pyramids near the same river. It's impressive that they did it at all I grant and the technical details are interesting. But I'd really like to know how they built Stonehenge with Welsh stone. No river there.

I know, I am being trite about it. It is interesting what they have found but it's not exactly new information.

Ramps, boats and good rope. I pretty much guessed that as a child but you know well done to those involved.

700c x23 bike tyres don't hold much air oddly.

600km vacuum tube, unlikely. All that hot sun makes things stretch. loss of vacuum results in 10t per square metre of air rushing at you at ~700mph. I'm not sure what the 'best case' is, that's the most likely failure and it's not survivable. Also you are moving at 700mph, a similar energy to a bullet but just a bit heavier in a 15t coffin. It's just nonsense like going to Mars, the radiation and loss of bone will not be possible to survive.

Ha, they definitely do. I have had tyres burst in my face and it was not fun, as the volume of air was low and the distance was a foot (bike tyre @120psi) or so the energy had dissipated to low levels but it was still a shock. Bursting lorry tyres can cause issues https://www.youtube.com/watch?... So please check your facts.

I mean air is indeed compressible. It still weighs something. Also isn't that basically what an explosion is, an over pressure event, wonder what happens at 10 psi (lower than the 1atm the vacuum tube will be under) https://en.wikipedia.org/wiki/...

This is an overpressure event. https://en.wikipedia.org/wiki/... It's equivalent to an explosion. It's not fun (or survivable at hyperloop speeds).

1.68s is not 'instantaneous'. Trained soldiers and athletes would struggle with that. You'd also have to be strapped in like a fighter pilot to have a hope of surviving. 3g is likely the top end for 'people' and 1g is around where the comfort level is. Also you'd be talking 10x the energy of an F1 car.

How is a 10psi explosive over pressure event? Which is less than vacuum failure, lets see what https://en.wikipedia.org/wiki/... says:

Reinforced concrete buildings severely damaged
Severe heart and lung damage
Limbs can be blown off

Huh, at 10psi that happens. excellent.

If it doesn't take at least 2 miles to stop you'll likely suffer fatal g force injuries, you are doing a mile in 6 or so seconds and you'll probably want no more than 3g deceleration (likely 1g would be at comfort level for most) which is 10 seconds from ~300m/s