We talk of positively and negatively charged particles. But what actually is a charge, what is the property of charge caused by?
Asked by: Keni P.
The only honest answer any physicist can give to this question is 'we don't really know'.
The facts we know for electrical charges can be summarized
rather easily, some particles have this property which
we call a 'charge', which comes in two opposite varieties,
which tend to cancel each other out; if they do, they
interact through what we call the electromagnetic
interaction, if not, they don't.
Even at the deepest level we know, of elementary particles,
charge seems to be an integral part of the particles,
quarks (which form protons and neutrons, and other heavy
particles) are charged, and so are electrons, muons, and
taus. There does not seem to be a 'particle' as such,
which makes them charged, and there has never been observed
an electron which has 'lost its charge', for example.
This is perhaps another demonstration of our fundamental
ignorance of nature. The very fundamentals, we do not know
how or why. We just take them as axioms, similar to
Euclidean geometry and build upon them. While the existence
of charge is not in question, what it is, what it is
caused by, and why it exists are questions we are
unable to answer.
Answered by: Yasar Safkan, Ph.D. M.I.T., Software Engineer, Istanbul, Turkey
'The strength and weakness of physicists is that we believe in what we can measure. And if we can't measure it, then we say it probably doesn't exist. And that closes us off to an enormous amount of phenomena that we may not be able to measure because they only happened once. For example, the Big Bang. ... That's one reason why they scoffed at higher dimensions for so many years. Now we realize that there's no alternative... '