Canonically, TL9 is essentially distinguished by the achievement of gravity
control technology, which (also canonically) includes both attractive and
repulsive control. This gives us floating cities (or at least floating
Imperial Palaces), air/rafts, GCarriers, et multae ceterae.

Arguendo, assume that the laws of physics do not admit of repulsive
gravitational manipulation. No floating palaces, no air/rafts or GCarriers
as we know them. You get attractive gravitational manipulation, and some
ability to do it directionally, and with controllable range. 'Blocking'
isn't possible, so no "anti-gravity screens (or walls)".

What are the effects on planetary construction, ships, vehicles, und so
weiter?

®Traveller is a registered trademark of
Far Future Enterprises, 1977-2017. Use of
the trademark in this notice and in the
referenced materials is not intended to
infringe or devalue the trademark.

--
Jeff Zeitlin, Editor
Freelance Traveller
    The Electronic Fan-Supported Traveller® Resource
xxxxxx@freelancetraveller.com
http://www.freelancetraveller.com

Freelance Traveller extends its thanks to the following
enterprises for hosting services:

onCloud/CyberWeb Enterprises (http://www.oncloud.io)
The Traveller Downport (http://www.downport.com)