Re: Reason and eloquence

Ray Haddad wrote:

On Thu, 15 Jun 2006 09:39:48 +0100, I said, "Pick a card, any card"
and "J.V.Ashby" <J.V.Ashby@xxxxxxxx> instead replied:

Ray Haddad wrote:

On Wed, 14 Jun 2006 15:56:43 +0100, I said, "Pick a card, any card"
and "J.V.Ashby" <J.V.Ashby@xxxxxxxx> instead replied:

Ray Haddad wrote:

I recall when I first heard of black holes and how shocked I was
to find out that something quite possibly existed in the real
world that simply could not be measured in the traditional sense.
It opened my mind, Chris, when I read how they were discovered.

Which story was that?

Explain the meaning of this question, John. Are you limiting
yourself to a single meaning of the word trying to be cute?

The question stands or falls on its own. My interest in your answer to
it (and Zen has correctly read my mind) stems from my life as a
professional physicist. I'm interested in which story about black
holes fired your enthusiasm (I can think of at least three
possibilities), because which one it was says something about what
sort of science influences people.

It was well and truly before I read Hawking's books, although I am
very pleased to read his explanations. I was a subscriber to many
journals relating to the physical sciences as it was a minor in my
education at one time. I settled on electronics engineering. The
reason? I was drafted into the US Military in 1970 and was forced to
resume my education in a variety of places whenever I could and
where ever I could. I'm glad that I didn't become a physicist now
but my interest is still there.


I note you haven't answered the question. The three possibilities that
immediately sprang to mind were:

The classical postulation of black holes by ?? in about 1780. He
realised that if a body was massive enough and compact enough (and he
determined what "enough" meant in this context), the escape velocity
would exceed the velocity of light and the object would appear black.
Of course, in those pre-relativistic times he didn't know that the
velocity of light was a cosmic speed limit. But what he did was to take
a very simple concept - escape velocity - and look at the extreme
consequences of it.

Then when Einstein produced his field equations of General Relativity,
it didn't take long for Scwarzschild to produce a solution with a
singularity (and then for Kerr and Newman to generalise the solution to
spinning and charged BHs). This involved some quite complex mathematics
to explore the consequences (again pretty much at the extremes) of the
new theory.

The third possibility was the excitement at the discovery of a strong
X-ray source, Cygnus X-1, which was widely characterised as a BH
(strictly speaking, the radiation was coming from the accretion region,
matter falling into the BH). This is an observation and a fairly
intuitive leap of fath to produce an explanation.

You can, I hope, see how the three differ. Which one grabs people's
attention and turns them on to science is of interest to me.

I don't really care if Zen guessed right this time or not. Next
time, beat him to his answer and give him your permission to speak
your mind for you. No backing out.

*** that. You posted at 23.46 my time, at which time I was enjoying a
pleasant shiraz and a good conversation about the purpose of the
education system. Zen posts for himself, I post for myself. Which I did
when I got to your post this morning. That others, in other time zones,
posted before me is none of my business.

The trouble you seem to have here, John, is that you want so badly
to be in a gang that you'll hook up with anyone. Even Zen.


Mind-reading, Ray? And just how am I hooked up with anyone? Your
paranoid fears that I was trying to trap you with a simple question
predate any intervention by Zen (other than setting off Chris.tine's
question that I originally answered).

WARNING: You'll fall on your ever present sword yet again if you
continue.

I'm not sure you really thought that metaphor through.

Really? You wave your sword at me regularly missing the mark every
time. Yet there you stand with it pointed in my direction yet again.


Well, that's all right then. If I fall on it I won't do too much harm to
myself, will I? Maybe a little bruising from the pommel in my stomach.

After
that, electrons and holes moving about in an organized fashion
through semiconductor materials made absolute sense.

Hmmm.

Quantum leaps and all.

In the same spirit of enquiry, can you explain that comment?

Figure it out.

As an aside, it's always been a peeve that people use quantum leap to
mean a major change in something, when a true quantum leap is the
smallest change possible in a system.

Do you know semiconductor theory? Explain hole theory without
mentioning a quantum leap once. I dare you.


I've spent about fifteen years writing software to model semiconductor
devices, I've published on superconductivity theory (which is similar
in some respects), I've been steeped in band theory, from tight-binding
to multiple scattering approaches. I think I can say that I'm
reasonably familiar with semiconductor theory. I wouldn't use the term
"quantum leap", mainly for the reason given above. I might use "quantum
transition", but more likely promotion from valence to conduction band.

Black holes
changed me forever and still fascinate me beyond all reason.

For me the facination lies, as with so much of modern physics, in
the beautiful consistency of the apparent paradoxes the theory
throws up.

Assuming you're not trying desperately to be contentious, is there
some reason for you to believe I that don't share that state of
mind?

Is there some reason for you to believe that I believe you don't share
that state of mind? My comment was in some ways a gloss on the musings
I had about trampolining out of a black hole in my earlier explanation
to Chris.tine.

Isn't there some school of thinking at the moment that implies that
a black hole may actually spit out mass as it boils around the event
horizon? I recall a show from the BBC here that had Hawking and some
other guy discussing (if that's the word) the likelihood of the
event horizon not being detectable if nothing ever came out.


That's what Hawking Radiation is. His first explanation was in terms of
particle-antiparticle creation by vacuum fluctuations. Then one of the
pair would be sucked into the hole and the other escape. The question
then was where did the mass/energy come from, and it was soon
discovered that the BH lost mass in the process.

john (of course, just because you're paranoid doesn't mean we *aren't
out to get you)

We? Would that be your new gangmate and yourself?

You don't remember mingoes, do you?

john (there was a time, which now is long since past...)
.

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