trapped mouse posted:

DontMockMySmock posted:

haven't read any of these books this is referencing, but I have to step in to object.

Using the centrifugal effect to simulate gravity is obviously a common thing in both science fiction and sometimes real life.


But, as is implied by the name of the theory that explains gravity, the pull of gravity is "relative." That means that two observers who are moving differently may disagree about the strength of gravity in a particular location (and both be correct). For example, if you are in an elevator that is not moving relative to the Earth, you'll conclude that you're feeling 1g of gravity. On the other hand, if you're in an elevator that is rocketing "upwards," accelerating at 9.8 m/s² in empty space far away from any planets, you'd also conclude that you're feeling 1g of gravity. But to an outside observer floating around in space not moving relative to the Earth, these two situations have wildly different gravity - the first, 1g, the second, 0g. And the thing is, no one is "wrong." Both frames of reference are equally valid. This is the key insight that led Einstein to develop the theory of general relativity in the first place, and it's called the "equivalence principle": gravity and acceleration are locally indistinguishable.

So if both of those observers activate an "anti-grav harness," what happens? Well, what does an anti-grav harness do? Does it set gravity to 0? If so, what does it do to the observer in the rocket-elevator in space? Do they get their 1g of gravity negated and float in their elevator? Or do they get their 0g of gravity negated and still feel the acceleration? The only way to resolve this paradox of perspective is to say that the anti-grav harness zeroes out gravity in its own frame of reference, for there is no other frame of reference that it might prefer. And so even though an outside observer wouldn't think of this as "gravity," the anti-grav harness would negate the effect of the acceleration and you would float in the accelerating elevator. Thus, your buddy who jumped off the balcony is fine. The effect of the centripetal acceleration actually is gravity, from the perspective of the anti-grav harness.

What makes a lot more physical sense, anyway, would be for the anti-grav harness to simply create a gravitational force in some direction and strength specified by the user, basically a gravity-powered jetpack. Then of course we don't even have to worry about the nature of the acceleration causing them to fall - they can counteract it with artificial gravity in the same way that they could counteract it with a jetpack or whatever.

Anyways, press F to pay respects to Iain M. Bank's understanding of gravity.

trapped mouse posted:

DontMockMySmock posted:

haven't read any of these books this is referencing, but I have to step in to object.

Using the centrifugal effect to simulate gravity is obviously a common thing in both science fiction and sometimes real life.


But, as is implied by the name of the theory that explains gravity, the pull of gravity is "relative." That means that two observers who are moving differently may disagree about the strength of gravity in a particular location (and both be correct). For example, if you are in an elevator that is not moving relative to the Earth, you'll conclude that you're feeling 1g of gravity. On the other hand, if you're in an elevator that is rocketing "upwards," accelerating at 9.8 m/s² in empty space far away from any planets, you'd also conclude that you're feeling 1g of gravity. But to an outside observer floating around in space not moving relative to the Earth, these two situations have wildly different gravity - the first, 1g, the second, 0g. And the thing is, no one is "wrong." Both frames of reference are equally valid. This is the key insight that led Einstein to develop the theory of general relativity in the first place, and it's called the "equivalence principle": gravity and acceleration are locally indistinguishable.

So if both of those observers activate an "anti-grav harness," what happens? Well, what does an anti-grav harness do? Does it set gravity to 0? If so, what does it do to the observer in the rocket-elevator in space? Do they get their 1g of gravity negated and float in their elevator? Or do they get their 0g of gravity negated and still feel the acceleration? The only way to resolve this paradox of perspective is to say that the anti-grav harness zeroes out gravity in its own frame of reference, for there is no other frame of reference that it might prefer. And so even though an outside observer wouldn't think of this as "gravity," the anti-grav harness would negate the effect of the acceleration and you would float in the accelerating elevator. Thus, your buddy who jumped off the balcony is fine. The effect of the centripetal acceleration actually is gravity, from the perspective of the anti-grav harness.

What makes a lot more physical sense, anyway, would be for the anti-grav harness to simply create a gravitational force in some direction and strength specified by the user, basically a gravity-powered jetpack. Then of course we don't even have to worry about the nature of the acceleration causing them to fall - they can counteract it with artificial gravity in the same way that they could counteract it with a jetpack or whatever.

Anyways, press F to pay respects to Iain M. Bank's understanding of gravity.

Facebook Aunt posted:

90s Cringe Rock posted:

It counters the local planetary or artificial gravitational field, as was clearly explained in the briefing the idiot in question wasn't paying attention to. This is not the same as spin gravity, because it's funnier that way. Heh, stupid merc stepped off a ledge.

Meanwhile the Covenant used proper scrith-repelling materials in their Banshees, just in case they ever had to fight on a Ring.

LifeSunDeath posted:

With enough voltage won't it still work?

DontMockMySmock posted:

The "local planetary or artificial gravitational field" loving IS the centrifugal effect ("spin gravity" as you called it). That's the whole loving point of general relativity - those two things, acceleration and gravity, are the same.

Sagebrush posted:

the dielectric strength of polystyrene is about 20MV/m, so in order to for the electricity to jump through roughly 4-cm block of plastic to your body and then ground to earth, you would need around 800,000 volts.

So the answer to your question is yes.

Facebook Aunt posted:

Wouldn't a centrifugal effect cause us all to fly off the planet? Gravity must be something else.

DontMockMySmock posted:

The "local planetary or artificial gravitational field" loving IS the centrifugal effect ("spin gravity" as you called it). That's the whole loving point of general relativity - those two things, acceleration and gravity, are the same.

DontMockMySmock posted:

Anyways, press F to pay respects to Iain M. Bank's understanding of gravity.

DontMockMySmock posted:

Air is 3MV/m so you can do it a lot lower and without even needing the fork.

theflyingexecutive posted:

liking banks is one of the coolest things about musk

DontMockMySmock posted:

The "local planetary or artificial gravitational field" loving IS the centrifugal effect ("spin gravity" as you called it). That's the whole loving point of general relativity - those two things, acceleration and gravity, are the same.

DontMockMySmock posted:

Well, yes, but there's also another source of gravity/acceleration in the form of a big ol' mass that pulls us to the center, overwhelming the centrifugal effect.

edit: the centrifugal acceleration you feel on the surface of the earth is about 0.034 m/s² times the cosine of your latitude. So even at the equator, where it's strongest, it's easily overwhelmed by the 9.8 m/s² downward from Earth's ordinary gravity.

Facebook Aunt posted:

Wouldn't a centrifugal effect cause us all to fly off the planet? Gravity must be something else.

Centrifugal force only works for the molemen inside the hollow world. Most goons aren't molemen.

bike tory posted:

All I'm hearing here is that I'm about half a percent lighter at the equator than the poles. Suck on that you haters I'm not fat, just high latituded.

MizPiz posted:

MizPiz posted:

Samuringa posted:

Volcott posted:

Homunculi from extremely horny intellectual property fate/stay night. Grown in vats by wizmen so they're older/younger than they look.

Volcott posted:

A HORNY SWEARENGEN posted:

Zetsubou-san posted:

MizPiz posted:

Zetsubou-san posted:

Softface posted:

Dabir posted:

thanks, sounds dumb