Science and the Top Quark
                         _________________________

                             Timothy Paul Smith

                             Department of Physics
                             University of New Hampshire
                             Durham, New Hampshire 03824
                             tps@fermi.unh.edu

Abstract
________

	In this paper I will describe `Baconian Science', the methods for 
investigating nature employed most of the time by modern scientist.  Also I 
list and discuss some additional principles of investigation, such as Occam's 
Razor, falsifiability, and so forth.  I will use the recent top-quark 
experiments as an example of the use of this method.  From these principles 
I argue that one can deduce what kind of  `natural laws' modern scientist are 
looking for and are restricted to.

I. Introduction
_______________

	How does modern strive to understand nature?  Does it proceed by the 
slow accumulation of observations,  with the systematic synthesis of these into 
some more general theorem or law of nature?  Or by leaps bumps, inspiration and 
revolution?  We like to think we are practitioners of what is called `Baconian 
Science',  a methodical procedure of refining our understand of nature.  Yet 
what we do in practice is more complicated then the technique described by 
Francis Bacon.  

	In section II of this paper I will briefly describe what types of 
understanding we might hope to obtain,  and the technique of investigation 
advocated by Bacon.  As an example I will describe how the recent experiment 
concerning the top-quark fit into Baconian Science.  In section III I will list 
some major criteria for science omitted, or at least not emphasized by Bacon.  
Among these are the roll of simplicity,  repeatability, comprehensibility and 
so forth.  Since this paper is meant merely as a brief overview of the topics 
many of the definitions are unsupported and simplistic.  

	The `scientific method' works if our idea of what the character of the 
true causes in nature are approximately right.  Our techniques reveal what 
characteristics we expect true causes to have. In section IV, I will describe 
these.

II. Knowledge and Baconian Science
__________________________________

	In twentieth century science we tend to shy away from such terms as 
`knowledge' and `natural laws' in favor of `evidence' and `theory', which 
indicate a degree of uncertainity.  Perhaps it is because we have seen too 
many `laws' debunked by new evidence.  Still, even if we view true and complete 
knowledge as unobtainable it is useful to have a working definition.

	Knowledge must be supported in three ways; evidence, truth and belief.  
Without evidence;  truth and belief is called faith.  Without truth; evidence 
and belief is deception.  Without belief;  truth and evidence is ignorance and 
misinterpretation.  The problem with a search for knowledge of nature is that 
we can obtain evidence,  we can develop belief,  but we can never know what is 
true.  

	Francis Bacon realized that the deciphering of a little bit of evidence 
can be difficult and misleading.  He faulted his predecessors for making the 
mistake of jumping, leaping, from a tiny bit of evidence to a broad and general 
`law of nature'.  He advised a more gradual approach to discovering what he 
called `true causes' or `primary axioms'.  First the synthesis of a few 
observations or experiments into a `lower axiom' or local law pertaining only 
to a subgroup of phenomena.  Then the accumulation of of these `lower axioms' 
into a more extensive `middle axiom', with an increased range of appropriate 
application.  Finally the culmination of `middle axioms' into true cause and 
the most general axioms.  He referred to this as the "Interpretation of 
Nature", as opposed to the "Anticipation of Nature" of his predecessors.

	"this is the true way, but yet untried." [1]

	I think the underlying reason for supposing that such a technique would 
reveal true cause is the belief that nature is consistent, that there are very 
few causes,  and each cause has a vast range of application.  This view of true 
causes is in one sense unsupported,  when we propose to use Baconian Science,  
the universality of causes is presupposed,  But if in practice one really can 
move from lower- to middle- to higher-axioms the proposition of the 
universality of causes becomes well supported by consistency.

	In our own century Thomas Kuhn would refer to this meticulously 
collecting of data to establish the properties and range of a `lower-axiom' as 
`normal science',  what most scientist do most of the time.  Undoubtly the 
recent measurement of the top-quark may have been exciting, but it was not 
revolutionary.  It was just part of normal science. Indeed a revolution would 
have taken place if the top-quark had not been found. The top-quark doesn't  
even move us from one level of axioms to the next.  It is just part of normal 
science,

	"For our road does not lie on a level, but ascends and descends; 
	first ascending to axioms,  then descending to works." [2]

The combination of theory and experiment/observation is still the cornerstone 
of modern science.  But as Bacon noted:

	"I that regard the mind not only in its own faculties but in its 
	connection with things, must need hold that the art of discovery 
	may advance as discoveries advance." [3]

III. Auxiliary Tenets of Modern Science
_______________________________________

	 I will now list a few additional tenets of modern science.  We 
realize, like Bacon,  that we can not directly know what the true causes are. 
However, given our idea of what a true cause are like there are a few  
additional test a theory must past to be acceptable.  Evidence is still the 
cornerstone of science,  but we apply additional criteria.

III.1 Occam's Razor
      _____________

	In the fourteenth century, William of Occam (or Ockham) wrote 

	"entities are not to be multiplied beyond necessity" [4].  

Important as Occam's Razor has been in the successive centuries,  it is not 
necessarily a test of truth.  There is no reason a priori why the true causes 
might not be complicated.  However Occam's Razor reflects how we would like 
the truth to be.

	In the case of the quarks, Occam's Razor was invoked in 1964 in the 
Gell-Mann [5] `Eight-Fold Way' paper,  in which the myriad of subatomic 
particles are shown to have an underlying symmetry.  It took a few years 
before the reality of the quarks were substantiated,  but now we speak of them 
with familiarity and near certainity.  The search for the top-quark was driven 
in part to gather further evidence  to support the `Standard Model' (the fully 
developed quark model),  which is a normal Baconian activity. However it was 
also realized that failure to find it would open Pandora's Box.  The 
alternatives to the top-quark cause havoc with the relative simplicity of 
the Standard Model.

III.2 Repeatability and Consistency
      _____________________________

	The truth which we want is repeatable and consistent with other 
evidence.  Are we putting unnatural conditions on the truth?  We insist that 
the truth  can not change in time,  it does not depend on who does the 
experiment.  The truth must be general enough to encompass a range of 
situations.  I think these conditions are not unnatural.  Rather consistency 
and the broad range of truth is part of our definition of what we are seeking.  
If the truth changed, it is not worth seeking,  what one learned today will be 
useless tomorrow.  If it changed in a predictable way,  that underlying system 
is what we would call the true cause.

	The top-quark has only been seen in one experiment,  and then only a 
dozen sightings.  The authors of the May 1994 paper [6] recognize this short 
coming and cautionly label their results as `evidence', not `discovery' of the 
top-quark.  Perhaps this prudence is justified ( the probability of being 
false events is "about the same as the chances that the first two cards dealt 
to you in a poker game are both aces" [7] ).  This problem of repeatability is 
uniquely difficult for such expensive experiments.  The CDF collaboration 
expects to continue to gather data but it may be some time before their results 
are independently verified.  However supporting  evidence of the existence of 
the top-quark may be gleamed from such unlikely source as cosmology.  The 
existence of the top-quark (what ever its mass) is consistence with models for 
the post big-bang cooling of the universe.

III.3 Causality
      _________

	Causality has two parts.  First we are interested only in theories that 
describe how `A' can cause `B'.  Theories that describe nature without causes 
abound (there should be nine heavenly sphere - since nine is a good number),  
but they do not answer the questions of why? to our satisfaction.  Causality 
also means a time ordering.  `A' the cause must happen before `B' the effect.

III.4 Falsifiability
      ______________

	Karl Popper [8] pointed out that a scientific theory must be 
falsifiable.  The point is two fold.  First,  although we can not know if a 
theory is true,  we can know if a theory is false.  A true theory will be 
consistent with the evidence, a false theory would only accidentally be 
consistent with the evidence.  The second point is that if one can not envision 
physical evidence which might debunk a theory,   then the physical evidence 
means nothing,  it was not a test of the theory.  Without evidence,  and still 
without directly being able to ascertain the truth we are left with only belief.

	The problem of falsifiability of the standard model is interesting.  
The standard model predicts the top-quark, but doesn't predict its mass,  Thus 
we didn't know where in energy (or what mass) to look.  There were only bounds 
on the mass (due to cosmology).  

	What if a theory is so complicated  we can not presently calculate 
predictions from it?  Is it scientific?  Or will it eventually be scientific?  
As an example consider a part of the Standard Model,  Quantum Chromodynamics 
(QCD).  QCD predictions presently defies our best attempts at computation.  
This theory, or any of its proteges  will have the difficulty that we can not 
test them completely,  if we do not know what they predict.

	This is not a new and unique problem with QCD.  Newton's laws of motion 
and gravity need The Calculus and differential equations to make their most 
powerful predictions.  Yet in `Principia' Newton used geometric arguments,  and 
thus did not describe the most convincing points of this mechanics.  Often 
mathematical methods followed the theory (vector algebra followed Maxwell's 
electromagnetic field theory,  and we continue to rewrite Maxwell's equations 
in newer field theory notation).  I expect that Newton's mechanics,  Maxwell's 
electromagnetism and QCD are all scientific at their inception because their 
form would allow testability.  A century after Darwin we are still striving to 
understand the consequences of evolution,  but Darwinian evolution is most 
certainly scientific.  I do not have an absolute prescription for recognizing 
a scientific theory which has not made a uniquely testable prediction,  but I 
expect that QCD are scientific and zoroastrianism is not.

III.5 Normal Science verse Scientific Revolution
      __________________________________________

	What do I mean by revolution and was the top-quark revolutionary?  
I will take scientific revolution to mean the redefinition of the working 
principles of a scientific discipline.  Thomas Kuhn [9] defined it in terms of 
a `paradigm shift'.  A paradigm is an experiment or an example phenomena which 
is used to describe a discipline.  For example,  in nineteenth physics, the 
dynamics of a moving body is described with references to billiard balls
experiment; mass, size, position and velocity vector.  In the twentieth century 
the paradigm for dynamics are quantum mechanical and relativistic; double slit 
experiments, and muon decay. No longer do we speak of position and velocity, 
but rather wavefunctions.  Even mass has changed.  Mass is defined in terms of 
energy, a la Einstein:

	E = m c**2

a concept unthinkable and unpronounceable in the language of the billiard ball 
paradigm.  

	With the introduction of quarks there was a revolution in physics.  We 
now distinguish between elementary particles (particles which can not be 
divided) such as protons, pions, and electrons,  and fundamental particles 
which are the basic building blocks of matter, such as quarks and leptons.  
Not only do quarks add a new tier in the hierarchy of matter,  but by their 
property of not being able to be directly observed,  they force experimenters 
to perform a new type of experiment.  Whereas the evidence for an elementary 
particle might be a track in a cloud chamber,  or a residence in an energy 
spectrum (such as the top-(anti)top resident observed at Fermi Lab),  the 
evidence of the quark lie in `deep inelastic scattering',  and `decay branching 
ratios', etc.. Whereas evidence of quarks [10] is revolutionary,  the evidence 
of the top-quark is part of normal science.

III.6 Comprehensibility
      _________________

	One may argue that comprehensibility is either not a necessary part of 
science, or perhaps already implicited and I need not repeat it here.  I add it 
to my list for emphasis.  First, if a theory is incomprehensible it become 
essentially uncalculatable and therefore untestable.  Also if I do not 
understand a theory I can not completely believe it.  If I have a partial 
understanding,  then the best I could hope for would be partial knowledge.  
My knowledge will never exceed my understanding and comprehension.

IV. The Character of True Causes
________________________________

	When we look at the tools which we have brought to bear in our 
scientific search for `True Causes'  ( or `Laws of Nature', a more popular 
term), we realize that there are underlying expectations for what these laws 
must be like.  It will be intelligible by humans (perhaps no single person - 
for the field continues to mushroom);  Occam's Razor assist in this.  And the 
laws will be a few universal causes.  The last decades have spouted `Grand 
Unified Theories' (field theories called GUTs) and `Theories of Everything' 
(string theories called TOEs),  but this is nothing new.  This is exactly what 
Bacon was speaking about were he talked about the raising up of lesser, middle 
and primary axioms.

	This characterizations of true causes seems so apparent that one might 
ask why the discussion?  I contrast this view of causes with the view of 
classic Greece and Rome and Medieval Europe,  which was dominated by the view 
that nature was defined by the categories which things are in, as per 
Aristotle's book "Categories". The role of the scientist is to list the 
categories and properly place all features of nature in there own niche. Both 
Lucretius and Dante tell us that the reason that fire rises up is that it is 
attempting to return to its proper position, in the sphere of the sun.

	A third view of true causes is most well known in the yin-yang image.  
The world's dynamics are a balance,  rather a see-saw between two opposing sets 
of forces,  yin and yang.  Pythagoras characterized it in his `table of 
opposites': limited-unlimited,  odd-even, rest-motion, straight-curved, 
good-bad etc.

V. Conclusion
_____________

	"A long-sought particle will complete a quest begun by the Greeks" 
proclaimed the New York Time [11].  I expect it may not be the end of the 
quest for the ultimate constituents of matter.  I am certain it is not the 
same quest stared by the greeks (their were asking the question of continuous 
versus void).  However the evidence of the top-quark is a textbook case of how 
modern science forms questions and attempts to answer them.  We ask the 
question what are the simple (Occam's razor and comprehensibility) and 
universal causes, the `primum mobile'.  We gather evidence, extend the
range of application and try to find where it fails.

	Which view of true cause (modern science, categories, or yin-yang) is 
right?  It might be argued that the one which is most `successful' is correct.  
If success means the detailed predictions then we must select the view of true 
causes embraced by modern science is right.  I am sure other `success' criteria 
may result in a different conclusion.  
	
	So finally what is the nature or character of the true causes? I expect 
it is not humans,  but can we ever be completely objective in our world view?



References
__________

[1] Bacon, Francis, "Novum Organum", XXVI.

[2] Bacon, Francis, "Novum Organum", CIII.

[3] Bacon, Francis, "Novum Organum", CXXX.

[4] William of Occam, (fourteenth century) often criticized 
	some metaphysics by saying 
	"non sunt multiplicanda entia praeter necessitaem".

[5] Gell-Mann, M., Phys. Lett. 8, p 214 (1964).

[6] CDF Collaboration, "Evidence for Top Quark Production in 
	(anti)P-P Collisions at sqrt(s) = 1.8 TeV", 
	Fermilab-Pub-94/097-E  (April 1994).

[7] Carithers, William Jr., quoted in the "Boston Globe", April 27, 1994.

[8] Popper, Karl, "Falsificationism versus Conventionalism" (1934), 
	"On the Sources of Knowledge and Ignorance", 
	Proceedings of the British Academy XLVI, p. 39 (1960).

[9] Kuhn, Thomas S. , "The Structure of Scientific Revolution", 
	U. of Chicago Press, 1962.

[10] Friedman, J., H. Kendall and R. Taylor, Rev. Mod. Phys. 63, 
	pp 573, 597, 615 (1991).

[11] William J. Broad, "New York Times", April 27, 1994.