Welcome to DU! The truly grassroots left-of-center political community where regular people, not algorithms, drive the discussions and set the standards. Join the community: Create a free account Support DU (and get rid of ads!): Become a Star Member Latest Breaking News General Discussion The DU Lounge All Forums Issue Forums Culture Forums Alliance Forums Region Forums Support Forums Help & Search


In reply to the discussion: Astronomy in a parallel universe [View all]

Lionel Mandrake

(4,096 posts)
4. Gravity is like magnetism in one respect.
Tue Jan 31, 2012, 02:41 AM
Jan 2012

Both are long range forces, because they are thought to be mediated by particles of zero mass: the graviton and the photon.

Gravity and electricity both involve inverse-square-law forces. Magnetism would, too, if there were any magnetic monopoles.

Kepler speculated that the sun controlled the motion of the planets via magnetic forces. Kepler's intuition that a force from the sun controlled planetary motion was on the right track, but forces and their relationship to motion were not understood before Newton. It turns out that magnetism is the wrong force, but there was no way for Kepler to know that.

Astronomy in a parallel universe [View all] Lionel Mandrake Jan 2012 OP
Very cool info - thanks jimlup Jan 2012 #1
You're welcome. Lionel Mandrake Jan 2012 #3
A note on Kepler's book describing the first two laws Lionel Mandrake Jan 2012 #5
What if gravity were like magnetism? mindwalker_i Jan 2012 #2
Gravity is like magnetism in one respect. Lionel Mandrake Jan 2012 #4
There actually is a gravitational analogue to magnitism... Salviati Jan 2012 #6
+1 jimlup Jan 2012 #7
Latest Discussions»Culture Forums»Science»Astronomy in a parallel u...»Reply #4