low temperature physics, solid state physics, self-organisation, etc
In the second item I've lumped together a great number of things: great advances in the physics of low-temperature systems, so-called solid state physics, systems that exhibit self-organisation ... and I've put an etcetera on the end. These developments do have some features in common, but the main connection is that I don't know much about any of them, certainly not enough to give a good pencil-sketch. They're in the list for completeness; read a good book if you're curious.astrophysics
Astrophysics is literally "the physics of stars", although the subject includes very exotic beasties these days, in addition to stars. The difference between the old astronomy and the new astrophysics has been made by improvements in technology and advances in theory: as well as telescopes, there are now very big telescopes, telescopes in space, instruments that "see" radio waves, infrared and ultraviolet light, x-rays and gamma rays; spectrometers which allow you to study the chemistry of stars and gas clouds thousands of light-years away, and Doppler instruments which allow you to do "seismology" on the sun, feeling how it vibrates - not a bad trick, considering that it's 150 million kilometres away.
The Hubble results show the
star is very hot (1.2 million degrees Fahrenheit at the surface), and
can be no larger than 16.8 miles (28 kilometers) across. These results
prove that the object must be a neutron star, because no other known
type of object can be this hot, small, and dim (below 25th magnitude).
Picture from Fred Walter (State University of New York at Stony Brook),
and NASA. The
full-size (759KB) JPEG,
the full text of the
press release
associated with this
picture, and many other interesting things, are available at the
Space Telescope Science Institute web-page;
the smaller-size picture included here
is reproduced with permission from the STScI.
A little something added for the WWW version of this paper:
This is the first direct look, in visible light, at a lone neutron
star, as seen by NASA's Hubble Space Telescope.
To give you a bit of the flavour of how far things have progressed: my own experiment was inspired, in part, by a discrepancy of a factor of two, between our predictions of what's going on in the centre of the sun, and our observations of what's going on there. Consider that for a moment. We have some precise, numerical predictions concerning the centre of the sun, which is separated from us by half-a-million kilometres thickness of very hot, very dense, ionised gas, that you can't see through; we have (a few) observations of what's going on in the centre of the sun, which is separated from us by half-a-million kilometres thickness of very hot, very dense, ionised gas, that you can't see through; the prediction and the observation agree within a factor of two; and almost the entire experimental community is worried about the discrepancy, and considers it significant. So significant, that there is a large and diverse experimental effort to try to resolve the discrepancy.
We are now at the stage of dealing with remote objects, out there in the sky,
in ways that were previously only supposed possible for controlled experiments
in the laboratory; it's remarkable how things have progressed.
particle physics
I've listed the "new physics" by categories, although the different categories
impinge on each other in sometimes surprising ways.
The experiment
on which I work, although it's inspired by astrophysical concerns,
is actually in particle physics: the study of so-called "fundamental particles",
the little bits and pieces you find when you keep pulling things apart until
you can't pull them apart any further. If you like, it's the study of the very,
very small, while astrophysics deals with things which are very large indeed;
despite this, the two fields are very closely connected, and science is
beginning to develop a bit of the flavour of the whole web of being,
from the very small to the very large, all linking in with each other.
Thirty to forty years ago, particle physics was a complete mess, with
two-hundred supposedly "fundamental" particles and precious little by way of
a rational system even for organising our observations. In the intervening
time, and several Nobel Prizes later, things are dramatically different:
there are a handful of entities which we consider to be basic - not quite as
few as air, earth, fire and water, but pretty close; and the theory which
deals with about half of the field is one of the jewels in the crown of
modern physics, making predictions down to ten decimal places or more,
which agree with the experiments down to ten decimal places or more.
That theory is built on the two truly fundamental developments in physics
this century, both of which took place well befroe the second world war:
relativity and quantum mechanics.
Some other consequences are that nothing else can quite make it up to
110 km/h (well, actually, the real speed of light, which is very much faster)
no matter how hard it tries; and that cars, trains, people etc.
are seen to shrink, and time run more slowly for them, when they move very
quickly - in other words, a lot of very-difficult-to-believe predictions
which we accept because they have passed every experimental test that has ever
been set for them. The extreme beauty of the theory, which I mentioned before,
is another reason we actually believe all this, as is the way it cleared up
a really fundamental discrepancy in the physics that went before it:
Einstein actually worked it out by thinking about the discrepancy in the
older theory.
(If you've seen the film Young Einstein: There's a scene where
Young Einstein develops the theory of relativity at the same time as he
invents surfing - he's chiselling a surfboard out of the trunk of a tree in a
coastal forest and thinks about surfing on a wave of light -
and this is surprisingly close to the how the real Einstein
thought of it. He was cycling in a forest somewhere in Switzerland, and he
wondered what the world would look like if you sat (or surfed, if you like)
on the front of a light wave. Of course he'd thought about the subject before,
and he knew the existing theory well and so on
[note],
but he developed the theory of relativity by taking that line of thought and
following it through.)
I left cosmology out of the list of the "new physics" for a few reasons:
it will bring us at last to the $64,000 question,
"what's God got to do with it?"; cosmology needs a more extended explanation
than the other fields which I've glossed over; and, an especially easy way to
sketch cosmology, at least for our purposes, is to talk about Stephen Hawking.
It is hard to overstate the importance of Stephen Hawking; of course people
try to overstate his importance all the time, and sometimes succeed.
If memory serves there is an episode of
Star Trek: The Next Generation where Sir Isaac Newton, Albert Einstein
and Stephen Hawking are summoned to the holodeck (in simulation of course)
to play a game of poker (of course) with the ship's resident android
(of course!) who wants to learn more about the nature of human genius. That
was probably overstating his importance a little bit: in physics, grouping
someone with Newton and Einstein is rather like saying that they appeared on
the Mount of Transfiguration, along with Moses and Elijah, to talk with
Jesus.
(Whether it makes sense to suppose that the universe as a whole
could spin around is a controversial question philosophically
[note], but this doesn't
concern us here.)
The instability means that something must be happening:
either the universe is collapsing in on itself, or it must be expanding
already (and the rate of expansion be slowing down), or some more
complicated motion (such as a rotation) must be occuring.
But it can't just be sitting there.
This falls out of relativity theory very neatly, and Einstein worried about this
a great deal, because a static universe (at least on a large scale)
was taken for granted in those days.
Stephen Hawking. Together with Roger Penrose - an equally significant person
in these matters, but someone who doesn't get as much press - he proved a
set of mathematical propositions called singularity theorems.
One consequence of these theorems is that there is no escape from
the "big bang" conclusion: the expanding
universe we observe cannot be due to objects falling together,
and then flying apart again.
So it's not just the idea that everything must have come from a big
explosion - it really seems that it must have been that way.
It appears that the universe started at some definite time in the
past.
The spectacular example in which Stephen Hawking has brought general relativity
and quantum mechanics together has to do with black holes, but we need a small
digression before it can make much sense.
The following illustration is something I dreamt up last night -
I hope it can make the situation clear.
Now if you shine light squarely into the first face,
it will bounce off the diagonal face of the glass, as if from a perfect
mirror, and emerge from the second face, back into the air.
The phenomenon is called total internal reflection,
and is used to make mirrors for periscopes and optical instruments, and so on.
(You can polish glass much flatter than you can polish a piece of metal, which
is why this technique is used.)
This phenomenon of objects "passing through" regions "where they can't be",
on their way to somewhere else "where they can be", is a well-known effect
in quantum mechanics. (It's usually called tunneling, from the
following metaphor: how do you get to the other side of a mountain range,
if it's impossible to climb over the mountain?
You tunnel through the mountain.)
What Stephen Hawking proved was that the same thing could happen with a black
hole.
But suppose you also take quantum mechanics into account:
if an object inside were to come close to the boundary,
and there were something on the other side of the boundary, to "catch" it
- could it leak from inside to outside the black hole, even though
it can't cross the boundary?
In fact it turns out, when you do the calculations, that the space around the
black hole is so distorted by the enormous gravity of the thing, that it can
provide the other piece of glass (if you like) and so particles in fact leak
slowly out of a black hole.
Rather than being "black", then, a black hole
actually glows dull red. A very dull red, in fact:
a black hole with the mass of the sun would have a "temperature" of about a
millionth of a degree above absolute zero, so it would glow such a dull red
as to be black for all intents and purposes. But a "black" hole with the mass
of a mountain would be not so much glowing white-hot, as
blazing white-hot, radiating energy away so fiercely that it would
evaporate in a very short time ... with complicated (and not entirely clear)
results.
Stephen Hawking didn't believe this result at first, and went to a lot of
effort to prove that it couldn't be true, but was eventually convinced of it.
When he first presented it to his colleagues
the chairman of the seminar told him it was total
rubbish ... but since then, everyone has gone back and checked the work, and
it seems to be true. It's called Hawking radiation now, this dull
glow leaking from otherwise-black holes, and that in itself is quite an
achievement, having a physical effect named after yourself. But as we mentioned
before, very little work has been done at the junction of quantum mechanics and
general relativity, and this one piece of work has been a spectacular success,
so the fuss is probably justified.
Now theologians don't wander about making claims on this basis
(well, not very often) but scientists get very, very nervous about this
because it says that the universe began 15 billion years ago (give or
take 5 billion years - there are some numbers in the "distance scale", and
hence the time scale, that are hard to pin down). What happened before
that? Did God put it there - did we just find the moment of creation?
Do we have to say that God created the Big Bang?
Once you get everything down to a point, it doesn't make sense any more.
If the universe is very dense, one can still work out how it operates,
but if you say that absolutely everything is contained in a point of zero size,
you are down to where the theory itself fails. So for all of
those years, general relativity has been saying "there is a point somewhere in
the past where I give up": there is a point at which science gives up, and we
have no further answers, and that's where the universe came from.
This is the sort of thing that makes scientists very, very nervous indeed,
because by agreeing to that statement, you're giving up on your explanatory
power.
General relativity gives up at the beginning of time, not just because there's
nothing earlier than the beginning, but because the beginning is a point where
the theory stops making sense. Hawking claims that there is one way we can get
around this problem:
instead of coming down to a point,
where the theory no longer makes sense,
the same line of reasoning that allows him to turn what is in general
relativity a solid boundary that nothing can get through (the event horizon of
a black hole) to something that leaks very slowly,
allows him to picture the beginning of the universe as a curved contour,
a blunt point if you like. This is a picture, of course, but the
four-dimensional geometry it represents corresponds to a universe smoothly and
continuously appearing from nothing.
There are still no times earlier than "the beginning", t-zero,
but it's a continuous surface on which the laws of physics apply,
rather than a "point" at which the laws of physics stop working. This is a
proposal. One has to use principles that aren't already there, but on a
technical level it seems to work: one can make the universe start like this,
although funny things happen to your idea of time. Hawking's point is that
instead of the theory pushing you back to a very early time where it stops
working and you have to invoke God,
you can make sense of it as a whole - the universe, from beginning to end, can
just "sit there" (if you like) and the equations of general relativity and
quantum mechanics can describe it from beginning to end.
Hawking calls this the "no boundary proposal", because there isn't a boundary
to the universe, the way there was before. There's not a beginning in
quite the way there was before, and this is where the famous phrase
"what place, then, for a creator?" comes from.
So despite the fact that he is often
depicted as having disproved God, or as claiming that there's no God,
what he's claiming is that there's no need for God to create things. He still
allows some idea that God might be needed, or that something like a god might
be needed to provide a reason for the universe's existence.
What Hawking has done is the equivalent of saying that the universe is a
self-winding watch. You don't need to say that there was someone 15 billion
years ago, or however long ago it was, who wound it all up. You don't need that.
But you still, of course, have the question "what is the watch doing there?"
Who made the watch, who made the clockwork - who made the laws of physics,
why do they take the form that they do, and why is there a universe there that
obeys them?
Stephen Hawking knows, and a fraction of the scientific community knows, how
to handle all of the mathematics of this "no boundary" proposal, but I think
it's fair to say that no-one really knows what to make of it. What is it
really? Stephen Hawking irritates philosophers when he talks about
things like imaginary time, because he has this scientist's pragmatism that
says, you don't need to worry about what's really going on, because the maths
works, it all hangs together, it's well-defined. That would be fine as far as
it goes - physicists often have to "trust the maths", without knowing
entirely what it corresponds to, if anything. But then Hawking makes claims,
not just about time (the thing that physicists put on graphs,
and use in equations) but "Time", time-with-a-capital-T.
For example, he once speculated aloud that it was "imaginary time" that was
"real" or fundamental, while the time that we know - as in,
"Time, time, time, see what's become of me", the time that songwriters and poets
talk about - is a figment of our imaginations. This is a very bold statement
concerning one of the notorious problems in philosophy: is there such a thing
as "God's time", what is the relation between time and eternity, time and change
and so forth.
With someone like Stephen Hawking you often have this problem. There is
something that has just shown up in a piece of mathematics, and you
don't really know what you're doing yet - but let's run with it and
see if it works - but then he slips into giving orders to philosophers and
theologians, as to what they're allowed to talk about, without doing the
philosophy and theology himself. This is a case of a scientist "trespassing"
on other people's territory [an idea discussed earlier in the conference].
This point shouldn't be overstated: if the universe really did begin
15 billion years ago, and it seems to have done so, then
this is relevant for thelogy and philosophy and the rest of it,
but it doesn't give scientists carte blanche to waltz into a
philosopher's office, or a theologian's office,
and start telling them how to use their own language, or what the issues are.
Now this picture of a man who lives in a wheelchair, and speaks with a synthetic
voice, with a mind that soars out to encompass the way the universe works, and
to say rude things about God, is a profoundly romantic picture: and it's played
as a human interest story. Stephen Hawking is played as a human interest story.
It's important to remember that there are other figures whom you haven't heard
of - there are other figures in the field whom I haven't heard of,
and I work "a few doors down" from the cosmologists.
So it's not just that the implications of what he's talking about are
significant, because they are, and it's not just that he's making speculations
about how they fit together with God, because he is, and (after all) he knows
more about cosmology than I do, and is worth listening to: but there is a media
element to Stephen Hawking. Suppose that a cosmologist with equivalent
credentials - well, there's no-one with equivalent credentials,
but another big name in the field - wrote a book, even if he called it
something as racy as A Brief History of Time and had it published in
airport bookstalls and so forth, it wouldn't sell in the same way.
It wouldn't get the notice, because it wouldn't have the human interest of
Stephen Hawking's work.
I spent the first half of this talk giving an outline of how physics
has progressed: to genuinely understand this material takes years
of study, not to mention natural ability.
Regarding cosmology, I work in a neighbouring field, and yet I am just an
interested observer of these matters. And in a year's time I'll be Dr Yabsley.
This is not accessible material. So the human interest makes a real
difference to the amount of attention which is given
to cosmological speculations.
Philosophers get discussed in The Mind of God, quite a lot of them,
actually, including Christian ones: Augustine and Aquinas are discussed;
St Thomas Aquinas is actually discussed in historical context -
those of you with a background in the humanities may not find this remarkable
but for a scientist to discuss a Christian philosopher in historical context is
pretty rare. To many scientists, and particularly to those who write for a
popular audience, philosophers before Sir Isaac Newton were just people who
didn't know any physics. I know that sounds silly, but that's how people talk.
Whereas in Davies ...
There is a discussion [in this book] of the relationship between
Greek categories of thought and the worldview of the Bible: that in Biblical
thought history proceeds from Creation, through the Fall, then the world we
know, where God intervenes in history, leading up to the Incarnation, and
finally coming to a climax at the end of time; that Greek philosophy works very
differently, and yet the western tradition is a development from both sources.
This from the same person who was coming out with the capital-S-Science
versus capital-R-Religion arguments nine years earlier.
Paul Davies went native in those nine years. He went native.
Do you remember Dances With Wolves?
There are two scenes in that film which particularly struck me.
One of them is only in the extended cut: it's what happens after the buffalo
hunters have slaughtered an entire hillside's worth of buffalo and taken only
the tongues and the skin; they haven't just slaughtered these buffalo which are
the province of the Sioux, but they've wasted what they've taken, treated it
with contempt. It's a horrible scene. But what's only in the extended cut is
that the Sioux make a war party, and go out and kill the hunters and scalp them,
and then spend the night dancing around the fire, rejoicing at the fact that
they've killed these men.
You see Dances With Wolves off in his own tent, feeling for the first time since
he's been with them, and he's moved closer and closer to them in life and
thought, how distant he is from these people. Despite all that they've come to
know of each other, there is a profound divide: "I cannot rejoice with them".
It was right to kill these men, but I cannot rejoice with them over the killing.
The other thing that struck me about the film was the point where he is captured
by the soldiers who have reoccupied the fort, who see from the way he's
dressed, and from the the fact that he doesn't want to come back with them, and
that he was with indians, that he has another set of loyalties now.
That whatever else you might say about him, he has a set of loyalties other than
to the American nation pushing westwards. And they say to him, "you went Indian,
didn't you," and it's like a curse.
Those two things are, in my view, what has happened to Paul Davies. He has gone
native: I described him as going in as a general to conquer religious territory,
but he has gone native, and started talking like, and thinking like, a writer
on religious matters. But at the same time he has all of the sensibilities of
the scientist he still is - and you still find him thinking in scientific terms,
and getting irritated with the way theological and philosophical writers do
things, and the way they give the science short shrift.
Very briefly some high points of the discussion in the book:
What was the cultural and religious background to this way of speaking: what
were people thinking about legalism and freedom, and what it means for God to
act, when scientists started talking about laws? What was happening to laws in
society, to the structure of government and the rule of law in society,
when people started talking about laws of nature?
How did we come to think in these terms?
The idea that a limited set of objects is in such-and-such a state when an
experiment, or a thought-experiment starts - that there are "initial conditions"
to the physics problem in mind - is much more humble than the project of
specifying how the universe began. And as Stephen Hawking tries to do,
can you apply this sort of thinking to why the whole universe is there
in the first place? It makes sense to start off an experiment, and see what
happens at the end. How do you "set off" a universe, there is no table-top on
which you can set it off: and it's important to remember that we're not
just talking about a big explosion in the sky, which might be like setting off
an experiment. The Big Bang, despite its name, is not supposed to be an
explosion in empty space like an overgrown firework, but instead is the point
where space itself, and time itself came from ...
[note]
What he's doing through all of this is stepping back: he knows all of the
science, and talks about it, and wrote maybe fifteen books between
God and the New Physics and The Mind of God, containing all
of the science and all of the speculation; and it's as if he says, Fine,
we've seen all that, and we've heard all that: why do we think this way,
and is it appropriate, and what might it mean?
This is a small question - granted it is an interesting question,
and it matters, but it is only part of the story. God, in any recognisably
Christian system - even in any theist system - does a lot more than
start things off at the very beginning.
Genesis 1-3 is not about God winding up the universe at the beginning
of time and letting it go: it has a lot more to do with purposes
and relationships and the meaning of the world, and it's crass to suppose that
"winding the universe up" is what it's all about. That's something that
Paul Davies now appreciates, for example, but many other people seem not to.
There are many who take this broad path. Has anyone read Richard Dawkins'
The Blind Watchmaker? It takes certain things about evolution and
beats everybody over the head with them, as if they were the answer to
everything, or as if natural selection were the one path towards reaching
some religious answers - or some irreligious answers, in his case, since he has
an (understandable) axe to grind against creationists, and maybe against God
too, I don't know.
Whereas for the narrow path ... what Paul Davies is doing is very difficult -
as well as knowing the physics, he knows a lot of theology and a lot of
the history and he's trying to think them together. And it's probably about as
hard as living in a cross-cultural situation like Dances With Wolves, and
probably about as comfortable.
But in the end, I believe that it's the only way to approach these matters.
There are enough people in the world who know a lot about a few things,
sitting on bar stools and telling you what the meaning of Life, the Universe,
and Everything is: there are relatively few people
who genuinely worry about what the issues are, and try to get their own
thinking straight before they start speaking -
and I know to whom I'd rather listen.
But has anyone thought about these things as being (calling on all of my
high school maths here) an asymptote, an asymptotic phenomenon, an infinite
regress that never really stops?
B.Yabsley:
Stephen Hawking has made some attempts at interpreting [that "blunt point"
beginning] which have produced violent reactions from philosophers who have
tried to understand what the words might mean.
But yes, some people who have tried to make sense of his beginning have done
so in precisely those terms, that you can get closer and closer and closer to
the start, but that there is no actual zero point. That is how some people
view this, yes.
D.Mitchell:
[That is more a question of interpreting or picturing the mathematics,
which crops up in other disciplines too] - it's no longer "pure science" ...
B.Yabsley:
Yes, you get into all sorts of tricky philosophical territory here,
because you're handling infinities, where you take an indefinitely large number
of indefinitely small intervals as you get closer to zero ... there have been a
number of mathematical developments this century on these questions, but
[as I read it] the [philosophical] situation is quite confused.
A.Katay:
Helpfully, again, you point out that in the end we have the God of the Gaps,
that what Hawking is arguing against is the God of the Gaps: God is only
relevant where we don't know, where there's a gap in our knowledge, put God in
there [to explain what we don't know, so that] where there are no gaps, there
is no God. Of course if you start by rejecting the God of the Gaps in the
first place, then what Hawking is arguing against I'm happy to argue against as
well.
But what that does is to leave Hawking with the same questions that Davies is
putting: the four questions, which (at least 2 of them) are "why" questions.
I'm just wondering what it is that makes people think that science and
"meta-science", metaphysical questions, are connected to each other?
How is it that, why do people make the leap to saying, because I know all of
this about science, I can now talk about the why-questions - where are the
connections between these things?
B.Yabsley
I think this is where Laurence's argument comes in [regarding scientists
"trespassing" on the territory of other disciplines] - if you are going to do
theology, you have to do theology.
A. Katay
Because Davies wants to make that kind of leap, he wants to go from physics
to God ...
B.Yabsley
The point is the following: Hawking sits there and spends the whole time doing
nothing but physics, or nothing but models, and then turns around and says
what the implications are for God, and reads them straight off, as if this were
obvious. Whereas, as you've said, if you didn't already believe in a Deist God,
who started everything off [and then left it alone] then what Hawking's talking
about [is not so relevant] ... if you are fundamentally disturbed by Hawking's
result then you have already given up on so much that any religion
believes about God ... that you might as well have gone home already.
And Hawking seems completely insensible of this fact.
Whereas Davies is talking about the new physics in the same way that a Biblical
writer might make reflections on Israel's history, or a philosopher or
theologian might think about the way things worked in the past, or someone
might contemplate the way the Second World War turned out, and
[draw conclusions about] human nature - they then go on to do the further
thinking, which is where all of those [questions and speculations come from].
The stuff in the Bible is
Q1.
[In that first picture], where you have everything coming down to a point,
is that general relativity ... is it just general relativity which is failing
there?
A1.
General relativity is what you're working with, but it's general relativity
which describes space and time, it's the theory of the "fabric" of the
universe ...
if you've heard people talk about "the space-time continuum", that's general
relativity that they're talking about
[so that that "beginning" is where space and time begin, it's where they come
from.]
If space and time stop making sense, then you've just lost the whole
ball-game: that's the idea.
Q2.
When you've got the space-time diagram rounded off there at
ten-to-the-minus-forty-something seconds, isn't there an article of belief in
physical cosmology that in that very small time, the universe multiplied itself
by ten-to-the-hundred-something times, so that in one of those many universes
all the physical constants just happened to take on the right sort of values
that allow us to be here and talk about it, whereas any other combination would
not?
A2.
Okay. I didn't want to talk about inflation today: that's what it's called,
[the rapid expansion at the beginning]. This ties in with [the question of]
doing speculation responsibly.
There are a lot of things about the universe that look rigged. Things where,
if a number were slightly different one way, or slightly different another way,
then not just that the universe would be different, but the universe would be
There are various ways of understanding this, and Hawking is a particularly
(I think) bad example of someone who will happily use things like the
Many Universe Interpretation where there are billions, uncountable numbers
of universes out there, and it's only in the very few where everything turns out
right that there are people to worry why it's turned out right, so, you know
- no mystery. Or, there's some system that happens in the beginning that rigs
everything [and ensures a sensible outcome: this is one of the motivations
behind the "inflation" idea.]
Now, he's not a realist, and so he doesn't get particularly bothered by tossing
off ideas like this, but [the rest of us have to ask] where did all of these
universes come from? I mean, where are they? Other people are left there
scratching their heads and thinking, "Hang on a minute, what are we committing
ourselves to?". And he's doing the equivalent of saying, you can make it work
out in the maths, so what's your problem? Again, it's the difference between a
pragmatic approach, something that allows you to get the predictions right,
which you do all the time - there are things that we don't understand,
we know how to work the maths but we don't understand them, and so that's
alright - but one can't do metaphysics that way, and [the speculations] you're
referring to are an example of [the problems one can get into in this area].
If you're going to do metaphysics (for example, to talk about God), you have to
have some sort of idea of what's real and what's not.
Q3.
Having looked at Hawking's work briefly ...
the conclusion is not very scientific [not ...] a rigorous scientific proof ...
he makes an analogy ... with quantum mechanics ... [but there are many
technical problems, it doesn't really work].
A3.
It's a proposal, yes, it's not a proof. I'd read it as having more mathematical
and physical content than you've suggested ... [but it does posit new
principles, you can't just get it from current theory without additions.
But many things are like that.]
Q4.
Has Hawking made any response to the writings of Davies? Any comments in
reply to what he's said?
A4.
Paul Davies actually admires Stephen Hawking - these are my criticisms that are
being made here, not Davies' [I didn't mean to imply that there was any
controversy between the two of them].
Q4, continued.
But has Hawking said anything about Davies' work?
A4, continued.
Not that I've noticed. More of what I've seen has been in controversy with
Roger Penrose, the other person who did a lot of that work on singularities,
which we referred to regarding black holes and the Big Bang ... the two of them
have almost diametrically opposed views on all of these matters.
Religious people often subscribe to that kind of experience, and I wonder if
work in a fundamental science ... comes with [that experience of] being in a
harmonised relationship with your environment: making a significant scientific
discovery, finding out something true about the universe must feel like that
[for the scientist] ...
This may be one of the reasons for the "rush of blood to the head" [that Bruce
described.]
A chaotic system is not just unpredictable "in practice", but
unpredictable by any finite being - a hitherto unimagined
kind of impossibility-in-principle. If you had a wind speed,
temperature and air-pressure monitor in every cubic metre of the
earth's atmosphere, and a computer the size of a galaxy, you still
couldn't do long-term weather prediction. Nor could you predict the
behaviour of certain simple pendula, or electrical circuits, even with
knowledge of the system to any level of detail.
This was an unexpected property for a deterministic system.
One can find the idea sketched out, without it's present mathematical
rigour, in some writers
(e.g. Richard Feynman's Lectures on Physics,
Volume I, Section 38-6; and I understand that Poincaré was well
aware of it at the turn of the century) but it does not appear to
have influenced the thought of the scientific community.
Even though quantum mechanics, which contains a
non-deterministic element, has long been accepted as a more basic
physical theory, many physicists have persisted in supposing that the
universe is deterministic "for all practical purposes": that
the universe, on the scale of rocks, rockets, cells, and animals,
is pretty much like a clockwork anyway, so any apparent indeterminism
at the foundation of physics doesn't matter, or doesn't have
large-scale consequences.
(Not to mention the continuing attempts to brush the non-deterministic
element of QM under the carpet.)
The discovery of chaos has undermined determinism at this
"macroscopic" end: once we discovered that there were deterministic
systems which were not like clockwork, it became hard to ignore the
extent to which physics has focussed on "special cases", i.e.
systems which are both
The time of the physicist - the axis of a graph which we label "t",
which is measured out with the tick of a clock, or the cycles of an
oscillator - may be only one aspect of the phenomenon, but at least
it's an aspect about which we can be precise.
And it's worth clearing up a common
misunderstanding of the idea of time running slowly in
some places (regions of high gravitational field) and some conditions
(motion close to the speed of light).
It is not a case of seeing the hands of the clock
"move slowly", or observing your body to respond slowly to your wishes;
nor is it a case of being in a disorienting state where the experience
of time is confused (as happens during Nearly-As-Fast-As-Light travel
in the novels of Ursula K. LeGuin).
Everything we know of relativity
argues that time-running-slowly would feel completely normal: you would
only discover the discrepancy after meeting up with someone with a
different history. The classic illustration is of twins, one of whom
stays on the earth, while the other embarks on a round trip at (say)
80% of the speed of light. While the stay-at-home lives through
17 years, the travelling twin would live through only 10 years. Both
would experience those years "normally".
Another popular view is that physics has shown time to be
"just another dimension of space", the famous "fourth dimension": I
have heard people dismiss all philosophical investigation of the
concept of time, on the grounds that physicists had now explained time
in this (hitherto unimagined) way. In my view this is
extremely
misleading. It is true that physicists, when they mean to be completely
precise, no longer deal with time and space separately, but with a
four-dimensional "structure" (it's not clear what word to use) called
space-time. But the three "spatial" dimensions are still
distinguishable from the "temporal" dimension:
they do not behave in the same way. At the risk of being
prosaic, one can move to the left or right, forwards or backwards,
up or down in space
- we still have absolutely no reason to believe that one can
move backwards in time. We cannot even control the "pace" at which we
move forwards in time - if such language even makes sense.
The troublesome thing is that the effect still occurs if the
"beam" of electrons is made very faint, so that only one electron is
travelling at any given time - and electrons (at least under some
circumstances) have definite, trackable positions, so you wouldn't
suppose they could wash through a barrier like that. Yet they
can, and so it appears we can't "keep track" of
everything (even in principle) as we used to believe we could.
Precisely what the "old physics" is assuming at this point - and which
of the assumptions is wrong - is a very interesting question,
to which there is not an agreed answer. The fact that many physicists
treat it as a non-question - usually by waving the word "paradox"
around in some way - doesn't help .
To my mind there is no obvious answer to that last question -
but this is not the same thing as saying,
that the idea of the universe rotating obviously makes no sense.
This is a very interesting subject, close to the heart of
physics and its philosophy; but the fact that (as it turns out)
the universe is expanding tends to push such questions to the
perimeter of the discussion,
as matters of "philosophy" (in the derogatory sense).
But one does have to be clear as to what one is about. A "law of initial
conditions" would be something on the same level as a "law of physics":
like the theory of relativity, or the principle of superposition in
quantum mechanics, or some other very fundamental idea. We can "see"
those laws or principles at work in the laboratory, and set tests for
them, and the like ... but how does one conduct an experiment on a law
of "initial conditions"? The universe, so far as we have any
reason to believe, began only once ...
This does not mean that the idea is to be rejected. What it
suggests is that the criteria by which one would judge candidate
"laws" of this kind will have to be different to, or at least more
extensive than, those by which we judge proposed physical laws.
Physics as a discipline, and physicists as practitioners,
are not well-adapted to discussion of unique, unrepeatable, or
otherwise "particular" events, and getting at their logic or inner life.
By contrast, this is the regular business of history.
So considering Hawking's "no boundary" proposal from this point of view:
he puts forward a particular (mathematical) "way"
for the universe to begin, claims that it gives an outcome consistent
(in some admittedly non-trivial ways) with what we observe,
and then elevates the proposal to the status of a law, claiming the
consistency as evidence. What are the "quality controls" on such a
procedure? One cannot repeat the situation in the laboratory, so one is
thrown back onto a rather narrow set of facts concerning which one just
has to make a judgement. Notoriously, there is room for disagreement
in such judgements: the practice of history (for example)
can be learned, and we rightly call it a "discipline",
and it has standards ... but it's not a
"science" in the same way that physics is a science.
To make a possibly unfair analogy: do you
believe that the Warren Commission said the last word on the Kennedy
assassination? Perhaps not. But does that mean that you believe the
conspiracy theory put forward in the film JFK?
And if so, why that conspiracy theory? Might it have something
to do with the powerful and skilfully-employed means of persuasion
used by Oliver Stone? Or the fact that your parents were impoverished
dirt-farmers in Montana, who taught you distrust of Washington and all
American federal bodies from an early age? What is the standard of
"consistency" being applied: what sort of coincidences or loose ends
do you consider to be reasonable, what sort do you consider to be
"suspicious" or to point towards some underlying principle at work -
and which explanatory principles (such as the American tradition of
theories of shadowy inter-agency conspiracies) are you prepared to
countenance?
Perhaps it would be a good idea to ask a professional historian for
some advice on this question!
Beyond this - and I should say that I don't have any substantial
disagreement with what Dr Wilkinson says - I find his approach rather
glib. I'm sorry to say this, because my friend chose this book as one of the
few sensible-looking publications on the "Science" shelf of a popular
Christian bookshop, the rest being creationist material etc. of the
most depressing kind. Good published material on scientific issues that seeks
to set out a Christian position is still pretty rare in my experience, although
anything written by John Polkinghorne would be a good start for someone
interested in more reading.
My guess is that Christian writers are too defensive when it comes to
scientific issues, and that the more popular the presentation, and the
more positive or "evangelistic" the writer's intention,
the more strongly they feel the force of entrenched
"science has disproved religion" prejudices. The presentation of issues then
becomes lop-sided, with all sorts of criticisms and caveats attached to the
discussion of scientific topics, while the explicitly "Christian" material
is given a clear run. I think this is counter-productive - you are unlikely to
be taken seriously by a critical reader with a differing view - but more
importantly I believe you're kidding yourself if you take this path.
Having said all this, I should repeat that I don't want to take issue with
Dr Wilkinson's specific statements; and Dr Polkinghorne, whose approach I find
more coherent, was after all happy to "strongly recommend" the book.
relativity
Relativity
theory has to do with what stays the same and what changes,
depending on where you are and what you're doing - standing still,
spinning around, sitting in a train, flying in an aeroplane or a rocket,
falling into a star, and so on. It's notable for being very difficult to
believe, for the wonderfully elegant lines of reasoning which were used to
deduce it, for its tricky mathematics, and the fact that almost all of the key
work was done by one person - Albert Einstein of course. There are actually
two theories of relativity:
special relativity (1905)
The special theory has to do with standing still, sitting in a train,
flying in an aeroplane or a rocket; those sorts of things. The surprising
prediction is that while a person sitting on a train will perceive the ground
to be moving, and vice versa (I guess you already knew that) absolutely
everybody will measure light to travel at the same speed, no matter how fast
they are moving themselves, where the light comes from, whether it's overtaking
you from behind or coming at you head-on. It's as if you were in one of two cars
on the freeway, and no matter how fast you drove or in what direction, you
always saw the other car to be travelling at 110 km/h compared to yourself.
This is not how you think of things working: if you are doing 100 km/h, and
the other car is doing 110 km/h, then you will only see it pulling away from
you slowly - and yet, in reality, you always clock the light at 110 km/h.
general relativity (1915)
The general theory of relativity
answers the same questions when gravity is involved - what is the same, and
what is different, when you are sitting on top of a mountain rather than at
sea level, orbiting the sun, falling down, and so on. It's harder to illustrate
and understand: one of the simpler predictions is that time runs slightly
slower at sea level than it does at the tops of mountains - not just your
watch running slow, but time itself running slow, a point we'll come
back to
[note].
This is even stranger than the things that the special theory of relativity
asks you to believe, but again, we believe it because all the experiments
agree: the best observation now agrees with the theory to something like one
part in a hundred million million, the limitation being that we don't have
clocks better than that yet.
quantum mechanics
Finally (and it's been quite a list) there is quantum mechanics, which is the
theoretical development over which the most ink has been spilt, at least in
popular books. All the talk about Schrödinger's cat; about throwing a
ball at a brick wall and having it go through two holes, a metre apart, at the
same time
[note];
the uncertainty principle; and, last and probably least, the "tao of physics",
is about quantum mechanics. The reason so much gets written about it is that
no-one understands it: this makes it very difficult to describe in a succinct
manner (it's much easier just to keep talking!)
and I'll leave it to the discussion time or to questions. I really mean
that no-one (or, no-one who isn't kidding themselves) understands it
properly, which is embarrasing since it has opened the door to about half of
the technological developments of this century. The theory in particle
physics which I mentioned before, which makes predictions which we've confirmed
in experiments to one part in ten billion, was made by putting
quantum mechanics together with the special theory of relativity.
That's pretty good for something you don't understand.
Cosmology and Stephen Hawking
I thought I'd get the "gee whiz" factor out of my system early in the talk.
This is important because someone telling you surprising things about the
world, or relating impressive details such as "the theory is correct to at
least one part in ten billion" runs the risk of "blinding you with science"
as the saying is - you just have to switch off and believe everything they say,
and you can't engage your critical faculties.
If you're the person speaking, it can cause
something of a rush of blood to the head. Being able to predict observable
numbers to ten decimal places is impressive, and until recently it had never
been done, but it doesn't mean that you're God - it doesn't even mean that you
know the mind of God. Physicists have been known to lose sight of this
occasionally. Those who work in the field called cosmology are,
at least according to other physicists, especially prone to this sort of
hubris, and there is a saying about them:
"cosmologists are seldom right, but never in doubt."
General relativity and the expanding universe
But he is very important - people have a reason for going on about the guy.
I mentioned general relativity before: one thing about gravity in general and
general relativity in particular, is that it makes the universe unstable.
The universe can't "just sit there", because each of the objects attracts all
of the others. If at some time everything is just sitting there,
stationary, then they will begin to pull together.
As the distance between objects becomes smaller, local irregularities or
"clumps" will develop (shown in black in the next picture),
but then these clumps will still be attracting each
other. Some objects might get "thrown clear" in close encounters with large
bodies, but on average the universe will fall in on itself faster and faster.
What eventually happens to it is not the point at issue right now,
although this will become important shortly.
The sketches are just to give you a general idea, and obviously the situation
is very different if everything is already moving around. For example,
if there's a slight overall rotation in some isolated system,
then eventually the
system collapses into a flat disk which "holds itself up" by each of the pieces
always moving sideways with respect to the centre - the whole system spins
around,
in other words. Both the solar system and our galaxy are like this.
But then in the 1920s, it was discovered that everything in the
universe is flying apart from each other, as if everything was on the surface
of a large balloon that was being inflated - or as if all the galaxies and so
forth were raisins in a piece of dough in the oven, moving further and further
apart as the dough rises ...
The "Big Bang"
That's what the universe is like. So suppose you run that backwards in time:
if everything is moving apart, then some time earlier
things must have been closer together; and even longer ago,
they must have been closer together still. Can you keep going? What happens?
That's the "Big Bang". If the whole universe is expanding like that,
at some point in the past there must have been a "big bang" that everything
came from. You may have noticed the flaw in this: what's to stop everything
from coming together (as in our previous series of sketches) but move sideways
a little and "miss each other", and fly apart again? ...
Black holes
The other thing Stephen Hawking has been associated with is
black holes, the sexy end of astrophysics. There are other versions of
the singularity theorems which say that when a star gets into a sufficiently
bad state of gravitational collapse, there is a "point of no return",
beyond which it will fall in on itself forever.
Eventually the star collapses into a body only a few kilometres across,
distorting the space around it so badly that not even light can escape from
its vicinity. That means that nothing can escape: you are left with a
"hole" in space ... things can fall into it but nothing can ever come out of
it.
And the material "inside" the hole continues to fall in on itself,
and finally collapses down to a point - of infinite
density? (a question we'll come back to).
A caveat:
I made some mention earlier of three basic theories in physics:
quantum mechanics, special relativity and general relativity. Everything
we've discussed so far concerning Stephen Hawking, the big bang and black holes
is taken from general relativity. The area where I work,
particle physics, takes its theoretical base from an uneasy combination of
special relativity with quantum mechanics. And I am no
theoretician, but an experimentalist, and a fairly humble one at that: together
with about 150 other physicists, I help look after one of the big pieces of
experimental equipment, and worry about the data which it provides.
This is just to put my own comments into some perspective - particularly as I
will be saying some critical things about Stephen Hawking very shortly. The
man is one of the principal workers in his field, whereas I'm a rather small
figure working a few doors down the road.
Hawking radiation
Stephen Hawking is one of the key people trying to work in general relativity
and quantum mechanics at the same time, treating problems where the
theories overlap.
We really don't know how to fit these areas of physics together: individually
they work, and give some of the spectacular results I mentioned earlier,
but they are radically different and (on the face of it) incompatible. A way
forward in this sort of situation is to address a specific problem and to
see if one can make some progress. This may (or may not) show the way forward
with the wider problem. It's perhaps like making a single trip of exploration
into unknown territory.
Suppose you take a block of glass in the shape of a triangular prism, cut
square at one corner and at 45 degrees at the other two corners; it has two
faces at right angles to each other, and a third, diagonal face.
No light emerges from the diagonal face of the glass into the air. But if you
bring another piece of glass very close to the first one, the light
can "leak across" from one piece of glass to the other and come out the other
side, even though there is no light "in the middle",
between the two pieces of glass.
From the point of view of general relativity, nothing can ever come out
of a black hole: it's as if
there is a boundary around the black hole (the "event horizon"),
and nothing from inside can cross that boundary.
"What place, then, for a creator?"
So what's all this got to do with God? Well: we said before that everything was
moving apart, earlier on it was closer together, and you can't get away from
the fact that ultimately, it must have come from an individual point at some
time in the past. The singularity theorems force you back, not to a small
exploding region, but to a point. So if you go back to the very beginning and
"count backwards" in some appropriately small unit of time
(perhaps ten-to-the-minus-forty-something seconds,
or something ridiculous-sounding like that), you will eventually hit a "zero"
at which the universe, not just the matter in the universe but
space itself, is contained in a point.
No boundary, no beginning?
Now according to general relativity "nothing can come out of a black hole,"
but in fact it can:
particles can leak out as Hawking radiation. Stephen Hawking has applied some of
the same thinking to the beginning of time.
No creator??
So you don't need a creator any more, to explain that "I give up" point at which
the whole theory stops making sense. The whole universe hangs together quite
happily by itself: this is the Big Idea that all of
A Brief History of Time moves towards. You don't need a
creator, so maybe there's no creator.
No reason???
But you haven't avoided the need for a reason for the universe:
Hawking claims that you don't need a creator for the universe,
but he doesn't claim that you don't need a reason for it. And he quite fairly
asks, what is the whole thing doing there in the first place? It might be
"just there", but what is it doing there?
The universe as a self-winding watch
Having all of these theories is like knowing how a piece of clockwork operates.
You have a very elaborate piece of clockwork which does everythng for you:
makes galaxies and stars, develops life, becomes conscious. The "I give up"
point in the past represents the clockwork running in such a way, that when we
project it backwards, we discover that it must have been "wound up" in the past.
At some point in the past someone or something must have wound up the clockwork,
or it wouldn't be running now. So you ask, "who wound up the clockwork?"
time, imaginary time, and Time
There are a few surprises hiding on that "blunt point", too. On the type of
cartoon we drew earlier,
time is on the vertical axis, and a contour that slopes upward
corresponds to what we'd call time "passing" or "flowing" normally.
(Well, more or less.) The blunt point at the "beginning" where the contour is
horizontal doesn't correspond to time passing, but to the dubious-sounding idea
of imaginary time. Now, anyone with university-level mathematics will
have some idea of what this looks like in the equations. But what is it
supposed to correspond to in reality?
A "human interest" story
I said that Stephen Hawking is very important, but that he can be over-rated.
This ties in with the discussion earlier in the conference about
scientists in the media and Hollywood and so forth, since Stephen Hawking
is a very big human interest story.
He suffers from amyotrophic lateral sclerosis: his motor neurones have been
slowly dying and wasting away for the last thirty years, to the point where he
can barely move. He should have been
dead twenty-five years ago, but he's one of those lucky (or unlucky!) people
for whom the disease progresses very slowly.
Paul Davies and The Mind of God
This is where we come to Paul Davies again - remember we left him fulminating
against the evils of Religion-with-a-capital-R.
Nine years after he wrote God and the New Physics, he wrote another
book called
The Mind of God: Science and the Search for Ultimate Meaning.
The quotation which serves as a frontispiece to the book is the last
paragraph of A Brief History of Time:
If we do discover a complete theory, it should in time be
understandable in broad principle by everyone, not just a few scientists.
Then we shall all, philosophers, scientists, and just ordinary people,
be able to take part in the discussion of the question of why it is that
we and the universe exist. If we find the answer to that, it would be
the ultimate triumph of human reason -
(Do you hear the edge to that?)
- for then we would know the mind of God.
The last sentence of A Brief History of Time, and a good summary of
its vision. But then a funny thing happens. If you listen to the subjects
Paul Davies discusses in The Mind of God, these are some of the words
and ideas that crop up regularly:
"laws of nature"
All of this talk about laws of nature: special relativity, general relativity,
quantum mechanics, they are all laws of nature and we are using them to work
backwards, and see how the universe was in the beginning. He steps back for
a minute and asks, why do we call them "laws"?
"initial conditions"
A related point: he writes
The separation into "laws of nature" and initial conditions that has
characterised all past attempts to analyse dynamical systems may owe more
to the history of science than to any deep property of the natural world.
This way of doing things, having a set of laws, knowing how things start, and
then running them forwards to see what happens: this is an idea that comes
from having an experiment that you can place on a table. You set up the
situation at the beginning, predict what happens in the middle, and see what
happens at the end. Can you apply that sort of thinking to the whole universe?
No conclusion yet
Conclusion? Well, there isn't a conclusion yet:
What does God have to do with it?
That list of things which I gave in "the new physics" is a list of
technical developments. The fact that we know about what's going on at
the centre of the sun
doesn't tell you anything about God straight away - it might not tell you
anything about God if you thought about it all of your life. It's not obvious,
interesting as the developments are, that one can go from a set of developments
in a technical discipline, and extrapolate them to begin talking about God.
And when you speak in that way, many scientists actually get annoyed:
it's not just the religious people who object to this.
What does it have to do with God?
Well clearly it has something to do with God: if we knew rigorously
that the universe had to begin at a certain point, that would have implications,
certainly, one might say "God has done it". But it's unlikely to be the
only reason you believe in God. Or, if the whole universe can sit there
"by itself", as Stephen Hawking claims, this didn't just knock out the
foundations of the world's traditions of religious thought:
this is not the basis on which people decided,
how-ever-many-thousand years ago, that there is a God.
In the beginning?
Did you notice that through all of this, Stephen Hawking is working with the
idea the God is irrelevant beyond that "I give up" point? The only way in which
God enters into the discussion is as someone to wind up the clockwork at the
beginning: despite the fact that God appears on every second page of
A Brief History of Time, it all comes down to the question,
did God "wind everything up" at the beginning, or did he not.
Old questions, newer questions
So rather than getting new answers to the questions we've had all along
(which is what Paul Davies was claiming in the opening of
God and the New Physics), we have new questions added on to the
old questions. Consider the "new physics" we briefly discussed: we know
immeasurably more about the universe than we did even 50 years ago,
and it provides a larger base for speculation and questions, and maybe even
answers. But that's still what it's providing: you can't do theology without
doing theology, you can't just do the physics: theological and
philosophical questions need to be tackled on their own terms.
A parable
Enter through the narrow gate; for the gate is wide and the road is easy that
leads to destruction, and there are many who take it. For the gate is
narrow and the road is hard that leads to life and there are few who find it.
As my friends will tell you, I have a tendency to moralise most issues,
and I'm going to moralise this one: I think it is irresponsible and
self-indulgent to take a field that you know very well
(as Stephen Hawking undoubtedly knows cosmology very well indeed),
stick almost entirely within the field the whole time,
combine that with whatever your own personal agenda is
(and I have no great insight into Stephen Hawking's psychology),
and then start saying what all of this means about God.
Discussion and Questions
Discussion with Andrew Katay (from SIFT):
A.Katay:
Just a comment, really: I thought you brought it out well, that the idea of it
all going back to a point where it all stops, and God coming in only at that
point, is an old argument ...
Questions and answers
(The following is a selection of the questions-from-the-floor. The quality of
the tape is very poor at this point, so some of the questions and answers have
been lost, or are restored from memory, between square brackets. Occasionally,
I've expanded one or two of my responses, also between square brackets, where
the verbatim text is less than clear.)
A comment from Laurence Emmett (from SIFT):
I think one of the reasons that scientists confuse themselves with theologians -
and this does have something to do with surfing - is that there's a point in
your life when what you are doing is very much being a useful and productive
part of your environment, things like surfing, or being in a relationship,
or some such. Things where you suddenly think, "This is what it's all about -
here I am in a proper relationship with my environment" - and the tendency is
to confuse this [with fundamental insight ...]
Endnotes:
There's a proposed HTML Version 3 footnote element (<FN>)
but I get inconsistent behaviour from my Netscape browser when using it;
therefore I've implemented these notes "by hand".
[Back to main text.]
Extended note to "chaos"
One disturbing effect of the "discovery" of chaos was a very subtle
undermining of determinism. The problem is difficult to put one's
finger on, and what follows is my best attempt:
Chaos and determinism
Chaos is sometimes called "deterministic
chaos": a chaotic system is one whose state at some point in the future
is completely determined by its state in the present (through
some mathematical equation), but in such a way that a tiny change in
the present state will have an unlimited effect on the state in the
future. This makes the system unpredictable in its detail:
where the pendulum will be in its swing, what the temperature will be
in Florida, etc.
The clockwork universe
For a long time, physics
was founded on Newton's deterministic equations of motion,
and physicists worked mostly on simple, well-behaved systems -
bridges, engines, rockets, stars, etc. This encouraged the
belief that the entire universe, without exception, was like a
clockwork, determined in every detail on the microscopic scale, and
as a consequence of this,
determined and well-behaved (at least in principle) on the large scale.
This is not the sort of proposition which you can prove, and
it's not even easy to test, but it has been widely believed.
Now we know about systems which are
and we have a fundamental theory which is, at least in part,
non-determinstic. It is no longer easy to be confident that
this indeterminism "doesn't matter"; and there is the additional
prospect that indeterminism and chaos could interact, say that a
50% / 50% quantum mechanical event on the other side of the galaxy
could influence the weather, or some other event, on the earth.
The revival of spirit?
It is tempting to go on to declare that physics demonstrates that the
world is
and moreover that spirit, final causes, God,
the interconnectedness-of-all-things, or what have you, are all
influencing the roll of the dice.
Maybe this is true (and I believe in all of these things),
but it is far too bold to suppose that physics has
demonstrated this. What has happened, rather, is that the
mechanistic vision of the world which (for all practical purposes)
excluded spirit, final causes, God, etc., is no longer
easily tenable. The argument on all of these questions thus has to be
re-opened. My own view is that physics provides both an input and a
control to the discussion, but that it will not be decisive on these
questions.
In other words, contrary to the impression one is sometimes given,
and despite the fact that Einstein was working as a clerk at the time
(the turn-of-the-century equivalent of a graduate student doing a pizza
delivery run,
perhaps?) he didn't rush into the university one day with one of those
"I have a new theory" photocopied sheets, that comes out of nowhere
and claims to solve all known problems. Being a genius is one thing;
being a crackpot is another.
[Back to main text.]
Time (to paraphrase St Augustine of Hippo) presents no problems until
you try to explain it, whereupon you discover how little you understand
it. How to describe time, what to make of our experience of
time (e.g. the way in which we experience the flow of events,
our own reactions and thoughts, which are often different to the even
ticking pace of the clock), and how to relate it to eternity,
or unchanging things, are all longstanding questions in philosophy.
[Back to main text.]
This doesn't actually happen, of course. But an "equivalent" thing
does happen with light, electrons, atoms, and so forth: if you aim a
beam of electrons at a solid wall with two holes cut into it, and
then look at the electrons which reach the other side,
the pattern cannot be interpreted as electrons passing through hole 1
or hole 2, but only makes sense if the electrons "wash" through
both holes at once, like waves hitting a break-water at the
beach.
[Back to main text.]
The problem is with that word "isolated". It's fine for the solar
system to be rotating, because there is an everything-else "out there"
which you can use to get your bearings and decide that you (the solar
system) are spinning around. But once you are speaking of the universe,
there isn't an everything else - since "the universe" means we
are including everything - so how can a rotation make sense?
With respect to what "system" would the universe be rotating?
[Back to main text.]
My comments on this issue in September were perhaps too sweeping.
There isn't anything intrinsically unreasonable about the idea
of a "law of initial conditions", or some principle which says,
the universe must begin in such-and-such a state. After all, the laws
of physics, which we hold to be absolute for all intents and purposes,
govern the shape and development of the universe just as certainly as
the particular configuration in which things "began".
[Back to main text.]
Bibliography:
A note on further reading:
After I gave this talk a friend drew my attention to the book by
David Wilkinson,
God, The Big Bang and Stephen Hawking: An Exploration into Origins
(Crowborough, UK: Monarch, 1996, 2nd edition), and asked me to comment on it,
since our topics are so similar. The first thing to note is that our approaches
are rather different: I've taken a very limited subject - Hawking's
"no boundary" proposal and its interpretation - and plumbed it as deeply as I
feel able, while Dr Wilkinson addresses a much broader range of issues. He also
sets out a positive Christian position on the relation of God and the universe,
which I haven't done.
First written 22nd November 1997; last modified 29th July 1998
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© 1998, Bruce D. Yabsley