Subatomic Particles
Let's examine the three elementary subatomic particles: electron, neutron, and proton. They’re organized like this:Subatomic Particle Charge | ||
– | 0 | + |
electron | neutron | proton |
Electrostatic Force
Let’s consider the electrostatic force first. If we take two helium balloons tethered so that they're touching, and add a static electric charge, then the balloons will move apart. Electric charge behaves like this:Electric Charge | ||
– | + | |
– | Repel | Attract |
+ | Attract | Repel |
Electric charge exhibits two states, positive and negative, where opposites attract and like repels like. Why doesn’t the electron simply crash into the proton in the hydrogen atom? The electron is attracted to the proton.
Magnetic Force
Magnetism behaves like this:Magnetism | ||
N | S | |
N | Repel | Attract |
S | Attract | Repel |
If we expose a compass to a magnet, then the magnet interferes with the compass needle. Magnetism exhibits two states, a north pole and a south pole, where opposites attract and like repels like.
Let’s combine the two forces: electric charge and magnetism. If we take a non-magnetic iron rod and touch it to a pile of iron pieces, then nothing sticks. However, if we wind a copper wire around the iron rod, attach the two ends of the copper wire to the terminals of a dry cell battery and touched the rod to the pile of iron pieces then some pieces will stick. This is an electromagnet.
Gravitational Force
If we hold an iron rod at arms length and let go, then it drops and hits the floor, and that would demonstrate gravity. Aristotle’s view of gravity is different from ours today. Aristotle observed that heavy objects fall faster than light objects. If we hold an apple and a feather at arms length, and let go of both at the same time, then the apple hits the floor first. Aristotle's notion of gravity is confirmed.But Galileo described a thought experiment where he dropped two objects from the top of the Leaning Tower of Pisa and they hit the ground at the same time, or so he claimed, and that’s how we think of gravity today. All objects fall at the same rate.
A modern demonstration of gravity is a sealed glass cylinder containing a penny and a postage stamp sized scrap. If we turn the cylinder end over end, then the penny falls to the bottom end faster than the fluttering scrap. Now a vacuum pump is attached to remove the air through a tube connecting the pump to the cylinder. Turn on the pump and continue to flip the cylinder end over end. The scrap will drop faster and faster each time, until it equals the speed of the penny.
Whether either of them knew it or not, Aristotle included air resistance in his explanation, whereas Galileo did not. Then Newton combined the idea that gravity acted on a falling apple in the same way that Earth’s gravity acted on the Moon.
Force Comparison
Let’s try to get a handle on the relative strength of these forces, shall we? An electromagnet can pick up iron pieces, which means that magnetism is a stronger force than gravity. We can rub an air filled balloon to give it a static charge and stick it to the ceiling, which means that electric charge is a stronger force than gravity. But how much stronger? Here's a table comparing electrostatic and gravitational forces of subatomic particles.Force (N) at Bohr radius (53×10-12 meters) | ||
Particles | Electrostatic | Gravitational |
Proton-proton | -8.213162×10-8 | 6.647344×10-44 |
Neutron-neutron | 0.0 | 6.665682×10-44 |
Electron-electron | -8.213162×10-8 | 1.971653×10-50 |
Proton-electron | 8.213162×10-8 | 3.620256×10-47 |
This table shows the force in Newtons between subatomic particles at the Bohr radius. The Bohr radius is fifty-three picometers. A picometer is ten to the minus twelve meters. A positive exponent means pad zeros to the right of the number, and a negative exponent means pad zeros to the left of the number. So minus eight means shift the decimal point left eight places.
For the proton-proton forces, the gravitational force has thirty-six more zeros than the electrostatic force. Forty-four minus eight is thirty-six. Thirty-six is four times nine, and nine zeros is a billion. So thirty-six zeros is four billions multiplied together. A billion times a billion times a billion times a billion. That’s a lot of zeros, and that’s a good thing, because the electrostatic force is what holds atoms and molecules together. If the gravitational force was stronger than the electrostatic force, then we’d all be squashed flat on a solid packed planet. No air. No liquid. No us.
The proton-proton electrostatic force in the first column is the negative of the proton-electron electrostatic force in the last column. Protons repel protons, and electrons repel electrons, but protons attract electrons. The gravitational force between a proton and an electron is much weaker than between two protons.
So why do we imagine that gravity is so strong? Well, notice that neutrons possess some gravitational force, but no electrostatic force. The electric charge of electrons and protons neutralize each other at atomic scales so in our experience gravitational forces appear to matter more at our level of consciousness. However, at the atomic level electrostatic forces dominate, that is except for neutrons.
Antigravity Hypothesis
Gravitation behaves like this:Gravitation | ||
↑ | ↓ | |
↑ | ? | ? |
↓ | ? | Attract |
What would antigravity look like?
An “electrically generated point of force” bubble appeared in scenes from ‘Explorers’. I animated the dream scenes for this movie.
A hovering mirrored spacecraft zooms around in scenes from ‘Flight of the Navigator’. I wrote the reflection map code for the spaceship, and Carl Frederick created the reflection maps. The Golden Gate Bridge scene was our test scene.
Electric charge exhibits symmetry. Magnetic poles exhibit symmetry. Why not gravity? Well, let’s assume that gravity does exhibit symmetry and see how far that takes us. The answers might teach us something about the true nature of gravity that doesn’t appear in any textbooks.
Here's what happens if we fill in the question mark fields in the gravitation table:
Gravitation | ||
↑ | ↓ | |
↑ | Attract | Repel |
↓ | Repel | Attract |
Normal gravity is the down arrow, and antigravity is the up arrow. Like gravitational forces attract, but opposite gravitational forces repel, at least hypothetically. But gravitational anomalies are something that we don’t witness everyday. Why don’t we observe antigravity, even within an entire lifetime? What would antigravity look like anyway?
Would antigravity act like electrostatic repulsion? Here's an AP Physics class video demonstrating a hair raising experiment with a Van de Graaff generator.
Or would antigravity act like magnetic levitation? Here's a product video from Levitation Arts.
Einstein discovered the equivalence of gravity and acceleration. An entirely antigravity planet, solar system, and galaxy would behave indistinguishable from our own, since like gravitational forces attract, but if a meteor with antigravity entered Earth’s vicinity how would it act? When a meteor with normal gravity enters the Earth’s atmosphere it accelerates and burns up due to friction. Since gravity and acceleration are equivalent, then antigravity and deceleration must be equivalent in a normal gravitational field. Mix normal gravity and antigravity and our expectations go out the window. A meteor with antigravity entering Earth’s atmosphere would decelerate, and barring a collision with anything solid it would stop and hover. Sound like any behavior you've ever heard of?
No comments:
Post a Comment