[ExI] The Great Silence again

[Keith Henson]

On Mon, May 2, 2011 at 3:50 AM, Stefano Vaj <stefano.vaj at gmail.com> wrote:
> On 30 April 2011 21:06, Keith Henson <hkeithhenson at gmail.com> wrote:
>> For a non rotating Dyson sphere that's thin enough the light pressure
>> would balance the gravity from the sun.  The light pressure at the
>> distance of the earth's orbit is around 9.3 N per square km.
>
> Now that you make me think of it, in a non-rotating Dyson sphere
> object on the internal surface would be bound to fall towards the sun,
> right? The gravity of even a relatively thick surface would hardly
> compensate...

No, but if it is a few hundred nanometers thick, the light pressure
will keep it in place.

When he was an undergraduate, Eric Drexler made aluminum films that
were around 200 nm thick.

That thin enough you could see a strong light right through the film.

Keith