TV Series: 3 Body Problem - affects gravitational force?

[DaveC426913]

TL;DR

SPOILERS

In the TV adaptation of the Novel "3 Body Problem", a Syzygy of all three suns in the system causes a cancellation of gravity and everybody goes floating upward.

SPOILERS


This obviously wouldn't happen to that extent, not without tearing the planet to pieces as well.

But might they feel a reduction in weight at all? Obviously it's a pretty hypothetical question without any specifics about the distances to the suns but in theory at least.

 

[Ibix]

It's actually the tidal gravity that matters - the difference between the solar contribution to gravitational acceleration at the surface and the solar contribution to gravitational acceleration at the core. The center of mass of the Earth is in freefall, and as long as the solar contribution to gravity is more-or-less constant across the planet (which it is - numbers below), you won't feel a thing no matter where the stars are.

Tidal forces drop off as the cube of the orbital radius, not the square, so they tend to be very weak. Wikipedia quotes the tidal acceleration of the Sun across the Earth as about $5\times 10^{-7}\ \mathrm{ms^{-2}}$, twenty million times weaker than Earth's gravity. That means that your weight varies by about one part in twenty million between midnight on the winter solstice and midday on the summer solstice - not detectable in humans, although I think lab equipment could see it in reference masses, and sea tides are a dead giveaway. In fact, if you took the planet away and replaced it with a marker buoy while leaving you floating in space one Earth radius away and equipped with a radar set to track the buoy, it'd be quite a while before you could spot that the buoy was changing position relative to you.

Obviously you can scale the forces up to create a situation where the tidal force is significant; an obvious example is a close pass over a small black hole. I'm not sure if you can construct such a situation while staying in the Goldilocks Zone of a pair of stars, though. And, as you note, I rather doubt the planet would survive unscathed. I'd also tend to suspect that, if such a scenario were possible and the planet could survive it, it would be likely to happen on a much shorter timescale than the typical lifetime of a planet - so there'd be no atmosphere left after a few occurrences.

 

[sophiecentaur]

I read the book on recommendation but found it pretty tedious. The Science was pretty loose and it got whackier and whackier towards the end. I didn't get on with the idea of such a complex game working on (ancient) PCs.
The initial plot was fair (historical stuff set the scene well) and I could go along with the politics. I guess there was some writing skill there because I followed it to the end.
I look forward to catching the TV series when I can get round to remembering.

 

[DaveC426913]

I didn't get on with the idea of such a complex game working on (ancient) PCs.

Ah. It seems they updated that for the show. The game was self-contained in a VR headset of fabulously-advanced design.

 

[Frabjous]

I guess that I will now start getting on the scale at noon.

 

[Filip Larsen]

The Science was pretty loose

The series seems to have kept the looseness, although as I haven't read the book so I don't know if they actually firmed it up a bit or not relative to the book. It initially comes off as a wanna-be hard sci-fi story but an abundance of science and techno babble (and plot holes) made me wonder if I would make it through all 8 episodes but somehow I managed. Perhaps due to the acting which I found quite good.

 

[sophiecentaur]

A bit of a mess really but I managed to find the Squid Game entertaining so best not be too fussy about details. Accuracy is really not necessary; take LOTR and GOT for instance.

 

[collinsmark]

I liked it so far (first 8 episodes). It's good.

But it's not perfect. But it's still good.

Setting the acting, special effects, direction and whatnot -- which are superb: top notch -- aside, let me stick to the physics, logic, and such:

The good:
Their use of necessary "hand-waving" is wonderful. When they do discuss known physics, they don't overstep their bounds. When they discuss General Relativity (GR), Quantum mechanics (QM), multiple dimensions and such, they are refreshingly quite good at admitting, "We just don't know," when it comes to the extremes.

I'm guessing they actually hired some physicists consultants for the script, and the writers/editors thankfully, actually listened to them. I find this really refreshing, since so many other movies, TV series, video games, etc., just throw physics out the window and just simply abuse physics if it helps the plot. If there is technology beyond what we know, 3 Body Problem does quite well at adding the necessary hand-waving to aid in the suspension of disbelief, even among those that understand physics. This is quite nice.

The bad:
I don't think they represent actually how chaotic a 3-body (or n-body) system actually is. [Spoiler alert:] The premise is that the alien world transitions from a habitable environment to a hostile one before inevitably transitioning back to a habitable one again (in somewhat random cycles). In reality, once such a system becomes non-habitable, it'll likely never go back. Ever. And if it does, it's a fluke, not something that can be counted on.

[Spoiler alert:] It seems to be a major part of the premise that the aliens seem not to understand the concepts of lying and fiction. Yet in their "game" there's a hypothetical Isaac Newton and a hypothetical Allen Turing among other hypothetical/fictional portrayals. They are portrayed hypothetically and fictionally. They are put in hypothetical scenarios that are not a true part of history. The aliens can understand that well enough. So what gives? Can they understand fiction or not?! "Make up your mind," I say.

 

[DaveC426913]

they actually hired some physicists consultants for the script, and the writers/editors thankfully, actually listened to them.

Not the writers/editors. Those guys are small fry along with the author usually. They care about authenticity.

It's the producers, who make the high level business decisions, such as "sex, sex ,sex, gotta have sex! Put a woman in there. And a sex scene."

the aliens seem not to understand the concepts of lying and fiction

Yeah. That's a bit weird - they sure seem to understand the power jumpscares and intimidation, as witnessed by the scene aboard the Learjet.