Re: Hooray: the Church of Scotland shows the way


"loiner2003" <loiner2003@xxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:7b98k0F22rfgrU1@xxxxxxxxxxxxxxxxxxxxx

Thomas wrote:
How many centuries must pass before in-comers feel comfortable within
their
new country? The Poles and Irish seem to accomplish this within a
generation
or two, there are (for example) few signs of Huguenot enclaves in Britain
and yet many well Anglicised Jews still put great pressure on their
offspring not to marry out. Surely there can be no more sincere a form of
racism than that?

I don't think that's a fair comparison. Most Anglicised Jews fit very
well into British society. But marrying out is a particular issue. In
Jewish understanding, "Jewishness" is passed on through the female, not
the male. So if a Jewish male marries a non-Jewish female, the children
will not be regarded as Jewish, unless conversion takes place. Marrying
out therefore puts Jewish identity at risk, and in a world where so many
Jews have been slaughtered already, the actual survival of Jewishness is
a matter of great import, to Jews anyway. An entire culture is at risk.
All this might seem bizarre to many of us, but it doesn't to Jews.


Well yes, you can rationalise it and dress it up in as much flowery language
as you like but racism is racism whether its the BNP deciding who's fit to
be British or Jewish parents deciding who's fit to marry their daughters.
And I really don't have that much time for people who try to appropriate the
sufferings of their ancestors - a crime against humanity is a crime against
the whole of humanity.


The scientific model as currently defined requires explanations/models to
be
presented in public terms that can reviewed and potentially falsified by
third parties. I'm not sure that an explanation which includes private
terms
such as subjective experience can fit into that mode. However I think any
explanation must stay close to the scientific model in spirit and any
objective elements it relies on must conform fully to that model. But
science isn't the only tool we have to explore and explain our
condition -
we also have mathematics, philosophy and the arts.

.which, of course, include religion! ;-) I agree.

Since relgion looks to an external agency to address these questions then I
would specifically exclude it on the grounds that it is dehumanising. More
to the point I would generally regard it as built on superstition and hence
not a reliable mode of enquiry.


Hang on a moment! I must be missing something. (Not at all surprising.)
You say human existence ...corresponds to a sub-set that arises due to
measurement processes. But it is us, human existents, that are picking out
the measurement processes. It cannot be the measurement process that
"creates" human existence. Can it?

Ok, we need to go back to a little basic quantum mechanics.

(This is probably completely off-topic and no doubt contravenes the charter,
but what the heck, here goes...)

By the mid to late 1800's scientists seemed to have the laws of the material
world pretty well sewn up. The world was divided into well localised solid
objects and into the more extensive fields of gravity, electricity and
magnetism. Newton had shown how the dynamics of solid objects could be
accurately predicted using his laws of mechanics and Maxwell had recently
shown how electricity and magnetism could be beautifully combined into a
single set of
equations which showed that light was actually a travelling electromagnetic
wave. In rather simplified terms, the material world was made of particles
and waves and scientists had the tools to deal perfectly with both of these
phenomena - the classical mechanics of Newton for particles and the wave
mechanics of Maxwell for light.

But this happy state of affairs did not last for long. Without going into a
full discourse, two observations were responsible for destroying the
delusion that the material world was largely understood; both of these
stemmed from the new field of sub-atomic physics which began with the
discovery of the electron. The first observation was that the new particle
called the electron also had the characteristics of a wave. The second was
that waves of light also had the characteritics of a particle - ironically,
Einstein received his Nobel prize for his contribution to qm rather than
relativity.

It turned out that the components of the material world could not be neatly
divided into localised particles and extended waves after all - each
component seemed be both particle and wave at the same time. A new type of
mechanics would be needed to predict the behaviour of the material world and
this new mechanics was quantum mechanics.

Unlike the other great pillar of modern physics, General Relativity, quantum
mechanics was not built on axioms - how could it be since it was so
counter-intuitive. Instead, physicists were dragged kicking and screaming
into this new scientific model - driven by empircal evidence rather human
intuition, indeed the great man himself would never fully accept that qm was
a complete model. It took a new generation of younger scientists like
Schrodinger, Dirac, Born and of course Bohr to slowly piece together a
crazy mathematical model which would prove to be astonishingly accurate -
whilst
all the time Einstein would snipe from the sidelines and keep everyone on
their toes.

With the benefit of hindsight we can retrofit some basic axioms to qm, the
important ones
are :-

- any physical system can be represented by a linear superposition of all
admissable state vectors. The result is a complex valued function (the wave
function) which is continuous in space and time;

- for any physical observable there exist corresponding complex valued
operators;

- the result of any measurement of an observable quantity can be predicted
by applying the corresponding operators to the wave functional
representation of system in a particular way;

- unless the system is in a special state with respect to the observable (a
so called eigenstate) then the result of the previous estimation will be a
probability function - we cannot predict a value with certainty;

- after a measurent has been made, the wave function of the physical system
collapses to an eigenstate of that observable with a value corresponding to
the one actually measured;

There are a few things you should draw from this. First, a physical system
extends over all of space and time - it is not localised. Second, a physical
system needs to be described by a complex function - however the phase of
this function is not an observable - we can never know it. It turns out that
phase/complex corresponds to some instrinsic and very mysterious property
called spin, the existence of which hints that our notion of geometry and
time is very much something that we impose on nature. Third, in the general
case we can't predict any measurement with certainty, but once we have made
a specific measurement the future (and past) evolution of the system must be
consistent with that measurement.

But there is one huge problem with the explanation I've presented so far.
I've talked about making a measurement on a system as though it were a
separate entity; it isn't, we are also part of that system and that's the
thing which causes the biggest philosophical problem for people trying to
get their heads around qm. It's this assumption that we can somehow talk
about a physical system as external from the observer that leads to much of
the rubbish talked and written about Shrodinger's cat for example. What is
needed is an understanding that includes the human observer as part of the
system and that's quite hard. I think this is the same mistake that
religious people make when they look to an external deity to explain their
humanity.

So to summarise, we have on the one hand the fully determinsitic and
continuous world of the wave function and on the other the bitty,
probablistic world that we experience through our measurements. Squaring
this particular circle is not an easy task - unless you belong to the old
school of "Shut up and calculate". Fortunately, many modern physicists are
now taking qm seriously and when pressed the majority will subscribe to one
of the many-worlds interpretations which abandon the notion that the wave
function collapses to one value on measurement and proposes that there is no
collapse at all, just decoherence (I believe there was a Scientific Americal
poll a little while back). Everything that can happen does happen,
but the result for an observer reliant on a particle based world for his
existence, is an increasing branching of the quantum world into orthogonal
classical worlds - the so called multiverse.

Now, when we come to address the question of where our humanity resides, we
need to also ask the question of how we find ourself following one
particular branch through the multiverse. Is our path just the result of a
set of partly probabalistic and partly mechanistic branchings or is there
something within our humanity which is able to steer our path. Alternatively
is our path determined by some optimisation process, are we intrinsically
good and does our humanity arise from a natural process in which the best
outcome always prevails? In other words, good will prevail - or perhaps,
what prevails is good!

For me it's all a glorious mystery which is greatly demeaned by the
imposition of some capricious external deity. I think we must begin with the
assumption that we do have something which can loosely be called free-will
and that our sense of being is indeed the result of a real underlying
process which drives us forward. The most important thing is that we
recognize and share our humanity with others and to this extent anything
which divides us as humans should be opposed - whether this is racism,
tribalism, sexism or religious doctrines that talk about chosen people or
elected
saints - there lies the true source of evil.

Anyway, sorry if I got a bit carried away :-)

There is a lot more to modern physics that my brief (well it was as brief as
I could make it) sketch leaves out. The most notable thing is the on-going
failure to reconcile General Relativity and QM - the big and the small if
you like. I'd like to finish by recommending what I think is a really good
non-specialist book:

"The Emporer's New Mind" by Roger Penrose ISBN 0 09 977170 5

There are many many people who will profoundly disagree with Penrose's
arguments and his conclusions (I have some reservations) but I think there
are few better introductions to the actual mathematics and physics behind
this fascinating topic.

I'm guessing that we are never going to convince each other about the value
of religion, however I suspect that we are actually a lot closer on many
things than we are to other members of this group. If all religious people
had your humanity and your sensibility then I wouldn't worry so much.
Unfortuantely they don't and I do.

Thanks for reading this far :-)

Thomas











.

Relevant Pages

  • Re: How can DHRs be This Stupid?
    ... a math into it later. ... different period than the surface observer. ... measurement purposes. ... yrs.) --- and the physics community at large for the last 20 yrs.) ...
    (sci.physics.relativity)
  • Re: Time dilation requires physical contraction
    ... The observer in my example can ... spaceship nor the observer's own transport. ... physics, everything relates to measurement in the end. ...
    (sci.physics.relativity)
  • Re: Why the speed of light is constant
    ... to the observer, any device the observer uses to attempt to ... But Indirectlly I consider Gravitational variance as a Effect Aspect ... could you observe a discreet wave. ... Using my view I can explain almost all of physics is very simple terms. ...
    (sci.physics.relativity)
  • Re: The true crackpots
    ... >>> depend on the motion of the observer. ... This does NOT mean that length contraction is a physical ... Length is the result of a measurement. ... > this point is available in Spacetime Physics, ...
    (sci.physics.relativity)
  • Re: a programm
    ... and be able to distinguish whether the measurement was affected by the ... Observer stands for any kind of experiment, measurement and the space of our observation. ... This is because we humans are important, but don't govern the laws of physics. ... The elements of spacetime are mapped into our observation-space according to some rules. ...
    (sci.physics.relativity)