Dyson Statite!

Originally posted by jaden101
There's also the problem that a solid Dyson sphere is gravitationally neutral and so anything living on the inner surface would just fall towards the star contained in it.

Although this is avoidable through a series of rotating outer and inner spheres.

That only gets you gravity near the equator and requires materials with ridiculously high binding energy. The amount of energy needed to spin it up is available to the largest powers in the setting but it's really easier to just alter people a bit.

If we cut off the top and bottom of the shell and call it a Niven Ring then we have a mass of 2e27kg (maybe less if we have better materials than Niven). It has to spin at 1.2million m/s to get 1G. A conversion engine would need 10000000000000000000000000 kg (~1.5 Earths) of matter to spin it up to that speed (unless the equations for spinning an object are different than for moving it). A solid shell will take a lot more energy. It's easier to just adapt people to love gravity.

Originally posted by Symmetric Chaos
That only gets you gravity near the equator and requires materials with ridiculously high binding energy. The amount of energy needed to spin it up is available to the largest powers in the setting but it's really easier to just alter people a bit.

If we cut off the top and bottom of the shell and call it a Niven Ring then we have a mass of 2e27kg (maybe less if we have better materials than Niven). It has to spin at 1.2million m/s to get 1G. A conversion engine would need 10000000000000000000000000 kg (~1.5 Earths) of matter to spin it up to that speed (unless the equations for spinning an object are different than for moving it). A solid shell will take a lot more energy. It's easier to just adapt people to love gravity.

For a hollow cylinder, it's m*R^2. I believe.

There's a lot more to that, actually. I don't remember anything else other than a solid being (1/2)m*R^2.

There's actually lots of more stuff that goes along with that...but the simple formulas are easiest to remember.

edit - *google searches*

I found something that might apply:

http://www.vectorsite.net/tpecp_04.html

There's bound to be your answer in there, somewhere. Also, what I found was MOI, so I don't think that that is the answer you were looking for.

I'm looking at what I wrote and I have no idea why I said "alter people to love gravity" it should read "alter people to not need gravity".

My understanding of your link isn't so great but it says:

v_a = v_l / r

v_a = (1.2e6 m/s)/(1.5e11 m)

v_a = 8e-6 seconds

Uh . . . which doesn't make any sense.

Originally posted by Symmetric Chaos
It moves a given volume of mass into the objective frame of reference. This lets me neatly handwave paradox and sound totally smart. Borrowing from the Known Space rules the drive doesn't work deep in a gravity well (though it fails harmlessly rather than destructively), however you can make the drive big enough to envelop a planet if you want at which point the planet's gravity is entirely in the drive field and you can move it FTL. There's a limited number of planets that are far enough from their star for this to work, but it does mean that extreme scale projects are just about practical.

(Actually, I do understand your engineering curiosity: I'm just bustin' your chops over what I feel is some inconsistency in tech capability).

Originally posted by Symmetric Chaos
I'm looking at what I wrote and I have no idea why I said "alter people to love gravity" it should read "alter people to not need gravity".

My understanding of your link isn't so great but it says:

v_a = v_l / r

v_a = (1.2e6 m/s)/(1.5e11 m)

v_a = 8e-6 seconds

Uh . . . which doesn't make any sense.

I knew what you meant. I didn't feel it necessary to be a jerk and, apparantly, no one else did, either. 🙂

Anywho, I could look in one of my old physics books. I think my first semester physics book covered that in the torque and power chapter. I remember something like what you're trying to calculate, being in there.

I'll check tonight. But, if it starts to take too long, I'm giving up. 😠

Originally posted by Mindship
Hokey Smokes: you possess a drive powerful enough to move whole planets faster than light!?

What, me personally? No.

Of the three groups in the setting capable of making their own drive only two trust the device enough to make regular use of it. The expense of even building a small one is very high, for the most part they have better things to do with their time and energy.

This isn't Star Trek where a drunk with a nuclear missile can go FTL.

Originally posted by Mindship
Is this Statite Dyson some sort of futuristic housing project

No, I set the population as 50 trillion Earth descended, real space, life forms (ie not counting aliens at all or AIs that spend most of their time in VR). The math at the beginning shows that they could all live in the counterweights and never meet one another. And before you ask the setting is X years into the future, where X is a number that gives me the population I want.

It's probably more like the housing for some manner of intelligence or an energy collector for ridiculously high energy research.

Originally posted by Symmetric Chaos
Of the three groups in the setting capable of making their own drive only two trust the device enough to make regular use of it. The expense of even building a small one is very high, for the most part they have better things to do with their time and energy.

This isn't Star Trek where a drunk with a nuclear missile can go FTL.

Originally posted by dadudemon
No, this is a thread about creating a semi-Dyson Sphere through staties built from a future material that is super duper ultra light and super duper ultra strong. Strong enough to support the solar collectors and a "pod" of lots of people. It will have a propulsion system in place and a counterweight, so that it will remain static around the sun to avoid the solar drift problem. It will require far less mass than the moon to accomplish. It's very plausible, actually. We just need to amp up or solar collection efficiency to something closer to 80%, imo. 😐

Edit - Oh yeah, there's also that material that doesn't really exist yet...cept for carbon nano-tubes.

That sounds pretty amazing, what size & mass does the counter weight have to have

Originally posted by Bicnarok
That sounds pretty amazing, what size & mass does the counter weight have to have

That depends on how big the sail is, how far away the sail is and how bright the star is.

Originally posted by Symmetric Chaos
That depends on how big the sail is, how far away the sail is and how bright the star is.

Sail has a 1500Km radius. It is 1 AU away and the star is about a 5 billion year old G V Class (G2V...see what I did there? teehee).

Ready.....GO! 😆

Isn't there an app for that?

Wouldn´t it be easier drilling a massive hole towards the middel of the earth and utilize this massive heat source in a similair way ground heat is being used already?

Originally posted by Bicnarok
Wouldn´t it be easier drilling a massive hole towards the middel of the earth and utilize this massive heat source in a similair way ground heat is being used already?

You wouldn't get nearly as much energy. I suspect the engineering problems of such a huge hole are enormous as well.