Ways to sidestep gravity?

From: "gardener1_98"
To:
Sent: Saturday, April 27, 2002 4:54 PM
Subject: [spacesettlers] Ways to sidestep gravity?

> Since the gravity well seems to be the biggst problem at the moment,
> here are a couple thoughts. One is that a Space Elevator is rapidly
> becoming feasible (apologies if this has been heavily discussed)
> thanks to tech like Carbon Nanotubes and the like. This seems to be
> the cheapest and fastest way to mass emigration to space. For around
> 1/2 the cost of the ISS we can have a permanent elevator in place, or
> so it seems to me.
>

I have already converted myself to the Space Elevator Cult. It will come and
free us all! ;-)

> Another thought is to "snap" the gravitational force around an
> object (like a space capsule) somehow. That is to say, that assuming
> the gravitational force is present in some physical form at the
> subatomic level (and I don't know much about this subject but here
> goes): could a powerful monomolecular (one molecule thick) laser
> shot create such an impact on a given area (like the air around a
> capsule) that it would separate all bonds, including gravitational
> bond, between the mass of the capsule and the Earth? And could a
> laser be built that would use a power source contained entirely
> within the capsule - surrounding the capsule enough with an
> enveloping, ultra-high-intensity beam, that it would separate all
> atomic and molecular bonds between the object or capsule and its
> surroundings, rendering it weightless and creating a miniscule total
> vaccum around it. Then all that would seem to be needed is enough of
> a push to overcome the 14.7 (or whatever) PSI air pressure to loft
> the object skyward. I know, it sounds bizarre, but chew on the idea
> awhile - is there any possibility that this could be done?
>

I am not sure if I understood the paragraph above correctly (I apologize in
advance if I'm making a mistake), but the impression that I got is that you
have a common popular misunderstanding of gravity: you think that gravity
acts only inside the atmosphere, and that astronauts in orbit do not have
weight because they are outside the atmosphere.

Well, that is not the case. Gravity propagates through the vacuum itself,
decreasing with the inverse of the square of the distance - that is, it gets
weaker when you go far from Earth (or any other object), but it is always
there. The astronauts do not have weight simply because the centrifugal
force caused by the circular movement of the ship or station counterweights
Earth's attraction. (That's the simplest way of explaining it, I think,
though it is not very accurate in terms of Physics.)

So, creating a vacuum sphere around an object would in no way render it
weightless. Maybe there is some way to control gravity and use it as a means
of propulsion - in a Universe with Dark Energy, gravitational anomalies in
our own Solar System and various other oddities, I would not rule out
entirely that possibility - but, even if it is possible, "gravitonic
propulsion" is certainly beyond our current science.

[snikt]
Lucio Coelho