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Name: Patrick E.
Status: educator
Age: 50's
Location: N/A
Country: N/A
Date: 1/13/2003


Question:
While gravity is the force which prevents escape of light from a Black Hole resulting in a "large" Schwarzchild radius due to gravity being a comparatively weak force compared to an electromagnetic force then is it possible that nuclear particles (quarks and leptons) could be "Black Holes" based not upon gravity as the operating force but upon the electromagnetic force such that the "Schwarzchild radius" would be much, much smaller?


Replies:
Probably not. Of all the forces operating on particles, only gravity has no repulsive component. It is always attractive. This statement may require revision, with the increasing evidence of the existence of "dark matter", but at our present level of understanding, gravity is always attractive. Whether this remains true at extremely high densities and temperatures just seconds after the "Big Bang" -- I do not think anyone knows. But (again at our present level of understanding) on the typical scale of galaxies, only gravity is solely attractive.

Vince Calder


Patrick,

A nuclear particle is not a black hole for several reasons. First, nuclear particles can easily emit photons of light. A property of a black hole is that most light going in does not come back out as light. Also, quantum physics poses a problem. The location of a nuclear particle is not absolute. Nuclear particles are just as much wave-like as matter-like. They do not have one exact location. They have a "distribution" of possible locations. Finally, the electromagnetic force does not work like the gravitational force. Gravity seems to attract EVERYTHING. Gravity provides everything with the same acceleration when at the same location. This allows gravity to be considered as an affect on space rather than on individual particles. This is the basis of Einstein's General Theory of Relativity. Mass "bends" space, causing everything passing through that location in space to experience the same acceleration. A black hole is space bent so much that moving the speed of light is not fast enough to overcome this acceleration and escape. When you get down to individual particles, no barrier is absolute.

Dr. Ken Mellendorf
Physics Instructor
Illinois Central College


No, I do not think so. The unique feature of gravity is that all the "charge" (mass) is of the same sign (as far as we know) and each bit of mass attracts all other mass, so as you add mass to an object, the gravitational force always increases. In electromagnetism, where there are two kinds of charge and each charge repels other charge of the same type and attracts charge of the opposite type.

Otherwise, black electromagnetic holes would be much smaller. If you could get rid of all electrons in every atom in the earth and in your body, when standing on the surface of this weird earth, you would be repelled by a force roughly 10E44 times larger than you are now attracted to the earth by your weight. That is 1 followed by 44 zeros times your weight!

You also cannot do it with the nuclear force, which is even stronger than the electromagnetic force. That is because the nuclear force is of very short range (10E-15 m). That is why nuclei are about that size. A uranium nucleus is about as close as you can get to a nuclear force black hole.

Quite a strange universe, isn't it?

Best, Dick Plano



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