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Have there been instances in physics where different scientists have interpreted the same data differently? If yes, can you please give me specific examples and explain why one interpretation was favored over the other?

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    $\begingroup$ Doesn't this happen, like, every time, hence the continual need to devise experiments that are know not to give results that aren't compatible with two different theories? $\endgroup$
    – Gae. S.
    Jan 11, 2022 at 16:16
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    $\begingroup$ Pick up any physics journal, and you'll see physicists interpreting the same data differently and explaining why their favorite interpretation should be favored. Or visit any lab, and you'll hear it, daily. Wikipedia lists 15 different interpretations of quantum mechanics, and those are just the "influential" ones. You'll have to be more specific. $\endgroup$
    – Conifold
    Jan 11, 2022 at 19:52
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    $\begingroup$ Maybe of interest - Underdetermination of Scientific Theory. $\endgroup$
    – nwr
    Jan 11, 2022 at 19:52

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The comments correctly say that this happens all the time. For a recent example, you can see my answer to: Can a highly-cited published paper have this type of error?

I will explain here some details which were not described in that answer (since your question is a slightly different one). The paper Engel et al., Nature. (2007) 446, 782-786 "Evidence for wavelike energy transfer through quantum coherence in photosynthetic systems" which currently has 3300 citations on Google Scholar was interpreted by many physicists to be evidence that quantum coherence is used by bacteria to help improve their efficiency at photosynthesis. The paper also says that some of the quantum mechanical behavior occurring in the FMO photosynthetic complex is "analogous to Grover's algorithm" in quantum computing. It was nearly universally interpreted that some bacteria near the bottom of the ocean, only get a few photons per day, and need to make sure as many of them as possible, successfully have their energy transferred to the reaction centre where photosynethsis happens, and that quantum coherence was at least partly responsible for this "transfer efficiency" being close to 99% in the FMO photosynthetic complex. People interpreted this as the bacteria evolving over billions of years to take advantage of quantum coherence.

My interpretation of the paper, published in Wilkins & Dattani JCTC (2015) 11, 3411-3419 "Why Quantum Coherence Is Not Important in the Fenna–Matthews–Olsen Complex", is that quantum coherence in the FMO photosynthetic complex does exist to some extent, but it is so short-lived that it has absolutely zero impact on the efficiency of the photosynthesis. Specifically, the solid lines in our figure below depict the dynamics including the effects of quantum coherence, and the dashed lines depict the dynamics with an incoherent theory:

enter image description here

The left panel shows that there's visible qualitative differences between the approximate incoherent dynamics and the much more accurate coherent dynamics (notice the oscillatory behavior which is characteristic of quantum coherent dynamics or damped Rabi oscillations), but only for the first 300fs or so. The right panel shows that both the incoherent and coherent dynamics equilibriate after about 5ps, which is an order of magnitude faster than the fluorescence time (which is multiple nanoseconds). Therefore, while the coherent dynamics and incoherent dynamics are both qualitatively different for the first 300fs, and the 2007 Nature paper did show evidence of quantum coherence (oscillations), the coherent and incoherent dynamics both lead to the same amount of excitons landing on the chromophore closest to the reaction center, and therefore the narrative about bacteria evolving over billions of years to act as a "biological quantum computer" or to take advantage of quantum coherence, is almost guaranteed to be an incorrect interpretation of the 2007 experiment.

Returning to the questions:

"Have there been instances in physics where different scientists have interpreted the same data differently?"

The above example is a specific example in which the same experimental data from 2007 was interpreted in two different ways. One in which quantum coherence is important for photosynthesis, and one in which it is not important.

"If yes, can you please give me specific examples and explain why one interpretation was favored over the other?"

The following are reasons why the first interpretation was originally favored:

  • The idea of quantum coherence (something required for quantum computers to work, but at the time impossible to maintain for long enough even in extremely expensive artificial vacuum settings) surviving in living cells was astonishing: the type of astonishing that gets papers published in Nature, and popularizes buzz terms like "quantum biology";
  • Quantum computing researchers also hopped on the bandwaggon since they could now apply the techniques they'd been developing for several years/decades to study quantum computers (which didn't exist yet and wouldn't exist in the near-term future at the time) on something that did exist, which was bacteria;
  • This not only opened computer scientists and theoretical physicists to the opportunity to publish about biology (a much higher impact field in which high citation counts and grant funding are more abundant), but also got people thinking this had implications for solar cells and the hot topics of developing clean energy, because solar cells had stagnated at less than 50% efficiency (see my post titled "What has caused this apparent stagnancy, in the development of more efficient solar cells?") and the FMO had an efficiency of 99%.

The reason why the second interpretation became favored in the long run was because concrete data supported it (see the above figure).

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