How can ship crew walk in USS Enterprise?

Question

Has there been a scientific explanation for ship crew walking in spaceships in Star Trek? I know rotating stations can create artifical gravity but USS Enterprise does not rotate, at least not enough to create a centrifuge.

Answer 1

The Star Trek TNG Technical Manual (considered a canon source of info about the Star Trek Universe) contains a wealth of Treknobabble explanation regarding the presence of gravity aboard ship. In short, the technology is very similar to that of the Tractor beam; a small device buried below the deck plating emits gravitons which then attract anything impacted by the particles:

The general planform of the Galaxy class starship returns to a more natural existence in that people are free to move about on planar surfaces with a constant gravity holding them to the deck. Aboard the starship, this is accomplished through the use of a network of small gravity generators. The network is divided into four regions, two within the Saucer Module and two within the Battle Section. All four work to maintain the proper sense of "down," and are also actively tied to the inertial damping field system to minimize motion shock during flight. The two Saucer Module gravity networks each support 400 generators; those in the Battle Section each support 200. Fields overlap slightly between devices, but this is barely noticeable. The gravity field itself is created by a controlled stream of gravitons, much like those produced by the tractor beam. In fact, the basic physics is the same.

Power from the electro plasma system (EPS) is channeled into a hollow chamber of anicium titanide 454, a sealed cylinder measuring 50 cm in diameter by 25 cm high. Suspended in the center of the cylinder, in pressurized chrylon gas, is a superconducting stator of thoronium arkenide. The stator, once set to a rotational rate above 125,540 rpm, generates a graviton field with a short lifetime, on the order of a few picoseconds. This decay time necessitates the addition of the second layer of generators beyond 30 meters distance. The field is gentle enough to allow natural walking without a gravity gradient from head to foot, long a problem in brute-force physical centripetal systems.

The persistence of power within the gravity generation system also explains why everything doesn't float off when the power goes out...

The superconducting stator remains suspended from the time of manufacture, and requires only an occasional synchronizing energy pulse from the EPS, normally once each sixty minutes.

Answer 2

It's pretty much ignored throughout most of the series, but there are a few times where the use of artificial gravity is mentioned, or fails:

• There is the malfunctioning anti-gravity sled in Hollow Pursuits;
• There's configurable artificial gravity on Deep Space Nine Melora;
• When visiting Empok Nor, the engineering team have to restore gravity;
• And then there's Star Trek: VI.

Actually, there's quite a few more examples: http://en.memory-alpha.org/wiki/Artificial_gravity.

About all we know, technically, is that there were gravity generators which feed gravity plating, and that's pretty much it.