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“What scientific idea is ready for retirement?”


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Wavefunction collapse, an idea that may be ripe for retirement (Image: A Friedman)

Every year since 1998, Big Questions guru John Brockman has posed one big question on Edge.org and gotten about forty or fifty of the world’s leading thinkers to come up with their own answers. This year the question is “What scientific idea is ready for retirement?”. The answers showcase a range of thinking and topics and they make it clear that every thinker interprets the word “retirement” differently. For some retirement means what it does, abolition to the shadows of polite discourse. For many others retirement really means refinement, to abolish not an idea itself but its interpretation. Yet other thinkers are annoyed with semantics rather than the content of the ideas themselves.

Here are a few of my favorites.

David Deutsch argues that the whole notion of “quantum jumps” is a concept way past its utility. Deutsch describes how the behavior of particles like electrons is often interpreted in abrupt, discontinuous terms. The truth though is that when you are observing these particles in phenomena like energy transitions in atoms or quantum tunneling, what you are seeing are continuous, changing probability distributions, not absolute disappearances and appearances.

The truth is that the electron in such situations does not have a single energy, or position, but a range of energies and positions, and the allowed range itself can change with time. If the whole range of energies of a tunneling particle were below that required to surmount the barrier, it would indeed bounce off. And if an electron in an atom really were at a discrete energy level, and nothing intervened to change that, then it would never make a transition to any other energy.

Similarly, Freeman Dyson wants to do away with the whole perception of “wavefunction collapse”. He makes the point that probabilities are not real and are actually a measure of our ignorance, so they cannot be treated like physical objects that disappear upon measurement. And asking what happens to a wavefunction after a measurement is irrelevant since a wavefunction does not exist then.

Unfortunately, people writing about quantum mechanics often use the phrase “collapse of the wave-function” to describe what happens when an object is observed. This phrase gives a misleading idea that the wave-function itself is a physical object. A physical object can collapse when it bumps into an obstacle. But a wave-function cannot be a physical object. A wave-function is a description of a probability, and a probability is a statement of ignorance. Ignorance is not a physical object, and neither is a wave-function. When new knowledge displaces ignorance, the wave-function does not collapse; it merely becomes irrelevant.

Other thinkers urge us to break down black and white distinctions. For instance here’s Steven Pinker arguing against the classic “behavior=genes + environment” dichotomy; the truth is that each one of them influences the other:

Gene-environment interactions in this technical sense, confusingly, go into the “unique environmental” component, because they are not the same (on average) in siblings growing up in the same family. Just as confusingly, “interactions” in the common-sense sense, namely that a person with a given genotype is predictably affected by the environment, goes into the “heritability” component, because quantitative genetics measures only correlations. This confound is behind the finding that the heritability of intelligence increases, and the effects of shared environment decrease, over a person’s lifetime. One explanation is that genes have effects late in life, but another is that people with a given genotype place themselves in environments that indulge their inborn tastes and talents. The “environment” increasingly depends on the genes, rather than being an exogenous cause of behavior.

Martin Rees strikes down the soaring belief that “we will never hit barriers to understanding” in spite of our spectacular current understanding of life and the universe:

There’s a widely-held presumption that our insight will deepen indefinitely—that all scientific problems will eventually yield to attack. But I think we may need to abandon this optimism. The human intellect may hit the buffers—even though in most fields of science, there’s surely a long way to go before this happens…

We humans haven’t changed much since our remote ancestors roamed the African savannah. Our brains evolved to cope with the human-scale environment. So it is surely remarkable that we can make sense of phenomena that confound everyday intuition: in particular, the minuscule atoms we’re made of, and the vast cosmos that surrounds us.

Nonetheless—and here I’m sticking my neck out—maybe some aspects of reality are intrinsically beyond us, in that their comprehension would require some post-human intellect—just as Euclidean geometry is beyond non-human primates.

Fiery Cushman tells us to abandon the belief that “big effects have big explanations”. He points out that sometimes many small explanations can add up to a big one and sometimes one small explanation engendered by accident can lead to catastrophe. This is true not just of science but of human affairs; for instance the reason conspiracy theories about the JFK assassination will always persist is because many people will simply be unable to accept the fact that a Big Event (JFK’s death) had a Small Explanation (Oswald). Similarly, think of the cause of World War 1.

Adrien Kreye argues against Moore’s Law and his explanation is similar to Martin Rees’s (and flies into the face of “singularitarians” like Ray Kurzweil): the fact that there’s been exponential progress in any given field by itself does not mean there will continue to be exponential progress in that field. Dean Ornish points out the shortcomings of large, randomized, controlled clinical trials, arguing that many interesting individual effects are averaged out in such studies. Finally, Peter Woit and Paul Steinhardt argue for the true retirement of two ideas which have not been supported by a shred of experimental support – string theory unification of physics and the multiverse.

Here’s my choice for an idea that should be retired: The idea that science is a concept-driven revolution. As with many other thinkers in that list I don’t actually think the idea is wrong or unimportant, it’s just that it’s overrated. New tools are appreciated far less than new ideas, especially outside the sciences. I propose that the idea that science is a tool-driven revolution should be given equal time. This is especially true for chemistry and biology which have been much more experimental compared to physics. Even in psychology – an idea-driven field if there was one – the advent of fMRI has engineered a revolution whose ramifications are still rippling across the landscape of psychological research. As Freeman Dyson says in his book “Imagined Worlds”:

‘‘New directions in science are launched by new tools much more often than by new concepts. The effect of a concept-driven revolution is to explain old things in new ways. The effect of a tool-driven revolution is to discover new things that have to be explained.’’

Unfortunately the concept-driven revolution idea came from Thomas Kuhn’s famous book. Kuhn was a physicist, and his biases dictated his views. If Kuhn had been a chemist his survey of scientific history might have led him to very different conclusions. Fortunately Peter Galison has been the pioneer of the tool-driven revolution paradigm, and his book “Image and Logic” remains the standard torch-bearer for this line of thinking. If we want to see science for what it truly is, we need to recognize the importance of tools as well as ideas.

What scientific idea do readers think is ready for retirement?

Ashutosh Jogalekar About the Author: Ashutosh (Ash) Jogalekar is a chemist interested in the history and philosophy of science. He considers science to be a seamless and all-encompassing part of the human experience. Follow on Twitter @curiouswavefn.

The views expressed are those of the author and are not necessarily those of Scientific American.





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  1. 1. rloldershaw 11:03 am 01/15/2014

    My candidate for “retirement” would be Absolute Scale.

    Absolute scale is the root cause of the hierarchy problem, the unnatural Planck mass, and the vacuum energy density crisis, for starters.

    Relative scale could not be continuous, but rather has to be a discrete or “broken” symmetry. It has been a long time coming but the general principles, the basics of how it works, and the means to test the new paradigm are readily available (see below).

    Robert L. Oldershaw
    http://www3.amherst.edu/~rloldershaw
    Discrete Scale Relativity/Fractal Cosmology

    Link to this
  2. 2. jtdwyer 12:53 pm 01/15/2014

    The “world’s leading thinkers” should consider which ideas have had the greatest impact on major fields of study while resisting definitive confirmation for the longest periods.
    - My nomination remains the requirement for dark matter – initially inferred solely from the discrepancy between the observed flat rotation curves of spiral galaxies and expectations loosely based on planetary systems. In the seminal work, http://adsabs.harvard.edu/abs/1980ApJ…238..471R – V. Rubin, K. Ford Jr. and N. Thannard concluded, based solely on observed flat rotation curves:
    “… This form for the rotation curves implies that the mass is not centrally condensed, but that significant mass is located at large R. The integral mass is increasing at least as fast as R. The mass is not converging to a limiting mass at the edge of the optical image. The conclusion is inescapable that non-luminous matter exists beyond the optical galaxy.”
    - This evaluation erroneously presumes that gravitational potential imparted to any galactic disk object is centralized rather than distributed at varying distance throughout the disk. Proper evaluations of distributed mass and gravitational potential produce flat rotation curves for disk galaxies based on visible structures alone, without requiring any extended halo of undetectable compensatory masses 6-10 times that of detectable galactic mass.
    - The long held idea that enormous amounts of undetectable mass exists in all galaxies has affected interpretations of observations in the fields of astronomy, cosmology, and theoretical and experimental particle physics.
    - Since no physical evidence for dark matter exists beyond those inferred by gravitational evaluation of large scale, compound configurations of innumerable discrete masses, I suggest that its original proposal be very thoroughly reevaluated rather than continuing to reinvest in confirmation efforts.

    Link to this
  3. 3. Uncle.Al 4:17 pm 01/15/2014

    Retire the Equivalence Principle (EP) by demonstrating its violation. Rewrite quantum gravitation to contain testable predictions.

    Physics arises from vacuum symmetries. Theory postulating exact boson photon vacuum symmetries for fermionic matter (quarks) suffers unending parity violations, symmetry breakings, chiral anomalies, Chern-Simons repair of Einstein-Hilbert action. The vacuum is trace chiral toward matter. Opposite shoes embed within chiral vacuum (mount a left foot) with different energies. They vacuum free fall non-identically, violating the EP.

    A geometric Eötvös experiment’s opposite shoes are visually and chemically identical, single crystal test masses in enantiomorphic space groups. Contrast right-handed versus left-handed alpha-quartz. Observe, repair theory, mourn the dead, and get on with the job.

    Link to this
  4. 4. RSchmidt 8:28 pm 01/15/2014

    I think we should retire the idea that science has nothing to say about morality or existential questions about life. There has been a perception that there are certain questions that are above science, that are free of its process and constraints and therefore they can only be answered by religion or philosophy. I see no practical reason that any aspect of the human condition is immune to scientific inquiry or cannot benefit from its dispassionate eye. It has been a case of shooting the messenger, where some don’t like the answers science provides in these areas and therefore they reject it completely. It is about time that we understand that if it can’t be known through science it simply can’t be known.

    Link to this
  5. 5. Dr. Strangelove 8:56 pm 01/15/2014

    Retire the idea that mathematical theories are equivalent to scientific theories. String theory and multiverse are mathematics. It informs science but science itself is built on observations and empirical evidence. Theoretical physicists are becoming pure mathematicians. They can no longer distinguish mathematics and science.

    I like the retirement of quantum jumping and wave-function collapse. These terms reflect our ignorance. A futile attempt to reconcile the bizarre behavior of subatomic ‘particles’ with the concept of a real particle. They are just semantics. We can call the observed phenomena “kaching” and they will not be more or less accurate than current terminologies. But it will not give the false mental picture of tiny spherical balls and waves moving in the air.

    Link to this
  6. 6. Dr. Strangelove 9:25 pm 01/15/2014

    “we should retire the idea that science has nothing to say about morality or existential questions about life.”

    Science can explain morality through psychology, anthropology and sociology. Metaphysics and theology are beyond science. The scientific method cannot be applied to things that cannot be observed. Science can explain why the human brain imagines things but not the imaginations.

    Link to this
  7. 7. rloldershaw 10:05 pm 01/15/2014

    Dr. Strangelove,

    I heartily second your three candidates for retirements.

    Too much theoretical hand-waving instead of empirical science for the last 50 years.

    Link to this
  8. 8. curiouswavefunction 10:56 pm 01/15/2014

    I agree with the proposals by Strangelove and others. The other day I heard a prominent science writer say that she is more enamored of mathematical elegance and exciting speculation than empirical testing. I sympathize with this sentiment but I don’t see how we can say what’s real based on mathematical elegance alone. Basically I think we need to reconsider science as it was described by Galileo and Bacon.

    Link to this
  9. 9. Dr. Strangelove 1:27 am 01/16/2014

    Ash
    The idea that math is the ultimate reality is as old as the Pythagoreans. Copied by the Platonists and still around today in string theorists and the like. MIT professor-physicist Max Tegmark has a new book “Our Mathematical Universe” that promotes the same idea. New book, old idea. The Pythagoreans have been ridiculed for their silly belief but string theorists who hold same belief are taken seriously.

    http://www.scientificamerican.com/article.cfm?id=is-the-universe-made-of-math-excerpt

    Link to this
  10. 10. verdai 5:01 pm 01/16/2014

    All true. Let’s agree and accomplish all this.
    nevertheless, the thing is not the word.
    the wave does wander.

    Link to this

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