How would the Machine at the Heart of the World tidally lock the Earth?

[Cerenkov]

https://en.wikipedia.org/wiki/Jack_of_Shadows

In Roger Zelazny's 1971 novel Jack of Shadows the Earth is held tidally locked by the influence of a vast machine at the planet's centre. No, the machine is surrounded by cold, solid rock and not molten rock... but never mind that. Anyway, I was wondering what kind of forces such a machine would have to counteract / compensate for to keep one half of the world in permanent darkness and the other in permanent light?

I can't offer much in the way of additional information, except for these items.

On the Dark side, where magic rules, that half of the world is prevented from freezing into Allwinter by the Compact. This is a loose confederation of sorcerers who unite to keep the Shield positioned directly above the Eastern pole of the world. Though it's never explicitly stated I suspect that the black sphere of the Shield is actually the Moon, which is being held at the anti-solar point by magic.

On the sunlit side, where technology rules, the Daysiders use nuclear-powered force screens to protect themselves from the Sun's incessant glare. Apart from the Sun being stationary in their sky their civilization is in most respects just like our own. They use computers, drive cars, fly planes and so on. But because it never gets dark their technology has never gone beyond the candle when it comes to providing illumination.

There is a Twilight zone between the Dark and Light sides where the influence of technology AND magic fade and are eventually nullified.

So, with the Earth not rotating on its axis and with the Moon held at the anti-solar point by magic, what stresses and forces would the Machine at the world's core have to deal with?

A follow on question from this is as follows.

Towards the end of the tale the Machine is sabotaged and destroyed to allow the Earth to begin rotating. The author describes such catastrophic effects as earthquakes, tsunamis, volcanic eruptions and devastating storms happening as the result of the rotation. Would that be all or would there be other effects as the Earth begins to spin on its axis?

Thank you,

Cerenkov.

 

[256bits]

Would that be all or would there be other effects as the Earth begins to spin on its axis?

I don't know why the planet would start up spinning, being tidally locked, and with the moon perhaps supposedly at Lagrange L2. Tidal locking is the evolution of moons with planets, and planets with their suns, over very long times and doesn't require magic or a machine.

Nevertheless, in the story, the earth begins to spin up for whatever reason.

 

[jedishrfu]

I imagine the machine was like a dad pushing their kid on a swing. You keep injecting a little energy with a push and after awhile let it decay or actively counterpush ie slow the swing by absorbing some of it's energy.

In truth though that wouldn't work but perhaps the spinning skater idea would work. Arms out to slow down and arms in to speed up.

 

[Bandersnatch]

Just reinforcing post #2 here.
If the Moon is out of the picture, by the virtue of it being held in place by magic, then there are no non-negligible forces in play. The Moon-less, tidally locked to the Sun state is the equilibrium the system is currently evolving towards. The only reason it won't get there is that there won't be enough time before the Sun leaves the main sequence.
I.e., the machines don't need to do any work, and nothing would happen if they turned off.