Philosophy Now-Aug-Sept 2019

(Joyce) #1
August/September 2019 ●Philosophy Now 13

“This is a sleight of hand by which they hope to convert an explana-
tory failure into an explanatory success. If we don’t understand... our
universe, just presume our universe is a member of an infinite and
unobservable ensemble of universes.... There is so much wrong with
this as a scientific hypothesis... it is hard to see how it could make
any falsifiable predictions for doable experiments.”
(quoted by John Horgan in Scientific American, January 4, 2015).

Moreover, consider what is perhaps the most popular theory
among theoretical physicists today: string theory. According to
Smolin, string theory “proposes that all the elementary parti-
cles arise from the vibrations of a single entity – a string” which
is so infinitesimal that it is invisible even to the super-sophisti-
cated instruments of modern science. But Smolin repudiates
the scientific status of string theory because it “makes no new
predictions that are testable by current – or even currently con-
ceivable – experiments.... Thus, no matter what the experiments
show, string theory cannot be disproved. But the reverse also
holds: no experiment will ever be able to prove it true” (The
Trouble with Physics, p.xiv). Smolin also sees other equally fatal
flaws in string theory. “Part of the reason string theory makes
no new predictions is that it appears to come in an infinite
number of versions... every single one disagrees with the pre-
sent experimental data” ( Ibid). He goes on to demystify the meta-
physical claims of string theory despite its clearly dominant
position in the world of physics today. “String theory... posits
that the world is fundamentally different from the world we
know. If string theory is right, the world has more dimensions
and many more particles and forces than we have so far observed.
Many string theorists talk and write as if the existence of these
extra dimensions and particles were an assured fact, one that no
good scientist can doubt. More than once, a string theorist has
said to me something like ‘But do you mean you think it’s pos-
sible that there are not extra dimensions?’ In fact, neither theory
nor experiment offers any evidence at all that extra dimensions
exist.” (p.xvi)
Fundamental physics has been taken as the model for how
all other sciences should develop. For dedicated empiricists like
Smolin, it’s a tragedy that “despite our best efforts, what we
know for certain about [fundamental physical] laws is no more
than what we knew back in the 1970s” (p.viii). He blames this
on the ‘arrogance’ of many of the string theorists. (p.269)


It Is ‘All In The Math’?
During the total solar eclipse in the fall of 1919, British astro-
physicists observed evidence that the Sun’s gravity bends the path
of the light from other stars, confirming a key prediction of Ein-
stein’s general theory of relativity. An insightful article by Richard
Panek in the science magazine Discover in March 2008 described
how Einstein interrupted a student who was trying to congratu-
late him for this scientific success, saying “But I knew the theory
is correct.” But what, the student asked, if the observations had
contradicted his calculations? Einstein replied, “Then I would
have been sorry for the dear Lord – the theory is correct.” It’s a
smug rejection of the positivist principle of empirical verifiabil-
ity. Einstein declared years later that “Our experience hitherto jus-
tifies us in believing that nature is the realization of the simplest
conceivable mathematical ideas. I am convinced that we can dis-


cover by means of purely mathematical constructions the con-
cepts and the laws connecting them with each other.” Panek nicely
sums up the momentous implications of the leap from the more
traditional method of empirical observation to Einstein’s faith in
thought experiments and the ‘mathematical imagination’. “For
thousands of years, researchers had studied the behavior of the
heavens and sought to capture it in mathematical terms. Einstein
reversed the challenge: he sought truth in equations and then
trusted that studies of the heavens would back him up. Almost
all of modern cosmology and theoretical physics follows from
that leap of faith – or leap, perhaps, of reason.”
Smolin is not buying any such ‘leap of reason’ – unless it’s
backed up by solid empirical evidence: by observations and
experiments that prove or disprove any proposed hypothesis in
strict compliance with both the Vienna Circle’s philosophy of
science and Popper’s insights. He writes, “once you reason like
this, you lose the ability to subject your theory to the kind of
test that the history of science shows over and over again is
required to winnow correct theories from beautiful but wrong
ones. To do this, a theory must make specific and precise pre-
dictions that can either be confirmed or refuted. If there is a
high risk of disconfirmation, then confirmation counts for a lot.
If there is no risk of either, then there is no way to continue to
do science” (The Trouble with Physics, p.169).

Non-Positivist Conclusions
So is the theoretical physics embraced by today’s heirs to Ein-
stein testable empirical science, metaphysical philosophy, or sci-
ence fiction? Einstein’s heirs seem to have forgotten Einstein’s
words of caution in 1933, that “Experience remains, of course,
the sole criterion of the physical utility of a mathematical con-
struction.” Lee Smolin adds his own warning: “Mathematics is
our most useful tool, but the idea that it should be prophetic has
done a lot of harm.” (Scientific American , January 4, 2015)
Panek’s Discover article concludes by identifying the enor-
mous challenges faced by the troubled field of cosmology, which
is now driven more by mathematics-based theory and ‘mathe-
matical beauty’ than by hard-nosed observation-based empiri-
cism. “These latest concepts all exist beautifully in the mathe-
matics, but so far observers have identified no sign of them in
the real world... How to move beyond slavish devotion to expe-
rience may have been Einstein’s greatest gift to the 20th cen-
tury. How to bring mathematical imagination back down to earth
may rate as his greatest challenge to the 21st.” If this challenge
is not faced, then future achievements in fundamental physics –
a field which is clearly “suffering from a surfeit of imagination
and a deficit of data” (Horgan) – may move ever further from
observation and testable prediction into ever more fanciful
realms of metaphysical speculation. After all, what is one to think
when America’s best-known living cosmologist, Dr Neil
deGrasse Tyson, following the philosopher Nick Bostrom, says
that the likelihood of the Universe being a digital simulation
“may be very high... And if that’s the case, it is easy for me to
imagine that everything in our lives is just the creation of some
other entity for their entertainment.” Indeed, is this ‘simulation
hypothesis’ itself a scientific theory, or pure science fiction?
© ROSSEN VASSILEV JR. 2019
Rossen Vassilev is studying at Ohio University, in Athens, Ohio.

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