Gravitational Fields and Electric Fields Part 1

ourben has asked the question, "Do like charges repel, or are they being attracted by unlike charges elsewhere?" There is a definite answer to this, but I take two parts to get there.

The answer is that we know like charges repel, and Faraday cages can be used to prove it.

Category:

Howto & Style

Tags:

• Gravitational
• Electrical
• Fields

[DarwinsHamster]

When particles interact (and all kinds of particles interact without being anti-particles of each other), the sum of each kind of quantum number (such as charge) must be the same after as before. If you have a total of zero charge, say, going in, you must have a total of zero going out. This can be achieved by producing many different combinations of out-going particles, combined with "photons" of the appropriate energy to make the mass balance.

[Luke12000]

that's cool so to check it you do a kind of arithmatic

[DarwinsHamster]

Exactly. When I took a subatomic particle course a long time ago, we made grids showing the type of particle down the left axis and quantum numbers across the horizontal axis (showing charge, spin, strangeness, charm, baryon family number, kaon family number (I can't tell you much more about that at the moment)) and all the other known quantum numbers. You then did something similar to balancing an equation to describe initial conditions and possible results.

[DarwinsHamster]

We have not observed anything with a negative mass. If we did, we would have to call it something other than anti-matter, because the term has already be appropriated for another purpose.

[DarwinsHamster]

An electron and positron are identical in mass, but the opposites in every other quantum number. When they collide, the quantum values are conserved (they disappear), and the mass is transformed into two gamma rays, each of 0.511 MeV (mega electron volts), traveling in opposite directions to preserve momentum.

[Luke12000]

just curiouse, how do we know that anti-matter has posotive mass

[DarwinsHamster]

Anti-matter is defined, or at least used to be defined, as subatomic particles that have all of the identical quantum numbers for charge, spin, strangeness, kaon family number, etc., including mass, except that the non-mass quantum numbers are multiplied by -1. When the a particle and its anti-particle collide, conservation of quantum numbers makes everything go to zero except mass, which is then transformed to energy.

[Fredricktator]

Just wondering how far along did you get in any math classes that you took and do you remember anything from calculus if you took it?

[Section41]

Did you learn this at Starfleet Academy?

[Luke12000]

I'll take your word for it...koan family number?