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UFOs as shown in movies are shown as disk like objects with raised centers that emit some sort of light from bottom. Can such a thing fly?

My very limited knowledge in physics tell me that a disk like object may not be able to maneuver unless it has thrusters on sides and simple light can not be enough to make any object go up in the air.

Is it possible?

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Seeing "beleived" in the question really bugs me but it's not enough to edit it. If someone finds a reason to edit this question, please correct the spelling at the same time. –  Carl Brannen Apr 14 '11 at 21:58
    
Can UFO's fly? ... Either that or the aliens must have a really strong placekicker on their team –  user346 Apr 15 '11 at 6:35
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Yes, there are many ways that allows a disk to fly, beeing lighter then air is one. –  user1708 Apr 15 '11 at 7:02
    
Infact there are many disc-shaped UFO made entirely of air hovering above you right now. –  user1708 Apr 17 '11 at 17:38
    
Ever throw a frisbie? –  Mike Dunlavey Jan 24 '12 at 1:30

4 Answers 4

up vote 3 down vote accepted

Beam propulsion has already been done here on Earth. :-) http://en.wikipedia.org/wiki/Beam-powered_propulsion

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google.com.bh/… so its possible I guess –  Hasan Khan Apr 14 '11 at 15:51
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Yep, but it's not just the light that provides the propulsion. (Not unless you have a huge amount of it) –  David Z Apr 14 '11 at 17:15

In mid 2010, Japan Aerospace Exploration Agency launched IKAROS, a spacecraft that is pushed by the radiation of the Sun.

Explanation: If you consider relativistic effects, light (photons) have no mass, but they can carry momentum $p=h/\lambda$ per photon particle, where $h$ is Planck's constant and $\lambda$ is light's wavelength. So, if UFOs can generate very bright light (very high intensity), theoretically they can push themselves against the gravity.

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Wouldn't that high density light cause everything underneath it to get burnt because of the heat produced? –  Hasan Khan Jan 15 '12 at 12:38
    
Yes, if it says "theoretically", it must work in highly idealized conditions.. but, for the UFO to get an upward thrust, it doesn't matter if the everything underneath it catches fire, (it is like propeling yourself on the ice rink by shooting ammunitions at the wall, you still get the force from recoil even after the wall has destroyed). In the movies we don't see anything that burns, thanks to the imagination of the artists. –  Sawi Jan 15 '12 at 13:14

The lift works on the craft body by interaction between the curren on which flows through the body surface and the magnetic field of the body center. ”The law on the left Fleming."

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Nope, while you can create forces by electric currents, you are still bound by Newtons laws. You have to overpower the gravity between the UFO and the earth, which means you need to exert a force on earth. The current/magnetic effect you describe would be limited to the UFO itself. –  MSalters Jan 16 '12 at 11:52

Have a look at the flying car

There is even a video.

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