what is anti gravity?

[v4vicky]

what is anti gravity?

[timo]

It's whatever you want it to be, from an escalator to the most powerful weapon in the Star Trek universe. Most people on Internet forums would probably argue that true anti-gravity has to be related to magnetism (that they don't understand, either - so the two things just have to be related, somehow).

[ajb]

To me it refers to situations in general relativity when gravity acts as a repulsive force. You can have such situations when exotic matter is present, for example.

 

However, I doubt this is what most internet forums would mean by anti-gravity.

[Dekan]

what is anti gravity?

 

We have balloons. They go upwards, against the downward pull of gravity. They exhibit the essential quality - defying gravity.

 

Suppose an alien spaceship arrives at Earth. And hovers pretensiously over New York. The upward-peering citizenry exclaim in awe: "Oy Veh - these schmucks must have mind-boggling anti-grav technology! See - their ship stays suspended in mid-air already!"

 

Then President Obama, after due consultation with Joint Chiefs and the latest CIA Director, concludes - "Nah, it's just a big Zeppelin - send up a coupla F-16's and bring the m-fing gasbag down pronto - no problem."

 

What I'm getting at is, why isn't a balloon regarded as a real and present anti-gravity device? What does it lack?

[D H]

What I'm getting at is, why isn't a balloon regarded as a real and present anti-gravity device? What does it lack?

What does it lack? Anti-gravity (which doesn't exist).

 

Balloons rise for the same reason boats float, which is buoyancy. Buoyancy is a consequence of gravity, not anti-gravity.

[Sato]

When I think of anti-gravity I think of quintessence as it defines a force that would be able to exhibit characteristics opposite those of gravity, not a force acting against gravity.

http://en.wikipedia....ssence_(physics)

Edited November 27, 2012 by Sato