Kevin's Watch

An émigré from Nazi Germany, Hans Bethe joined Cornell’s physics department back in 1935. There, he built a remarkable career for himself. A nuclear physicist, Bethe made key contributions to the Manhattan Project during World War II. After the war, he brought stellar young physicists like Richard Feynman from Los Alamos to Ithaca and turned Cornell’s physics department into a top-notch program. In 1967, he won the Nobel Prize for “his groundbreaking work on the theory of energy production in stars.”

As a tribute to Bethe, Cornell now hosts a web site called Quantum Physics Made Relatively Simple, where you can watch three lectures presented by Bethe in 1999.

Transistors replaced vacuum tubes. I suppose most of you are old enough to remember vacuum tubes, which were the predecessors of transistors.

Vraith wrote:Well...this could be fun.
[[[though not really on topic---it doesn't seem to be simplifying
First, the [relatively] easy/descriptive article on it,
Then the work by the guy with all the maths.

"George C. Knee, a theoretical physicist at the University of Oxford and the University of Warwick, has created an algorithm for designing optimal experiments that could provide the strongest evidence yet that the quantum state is an ontic state (a state of reality) and not an epistemic state (a state of knowledge)."

https://phys.org/news/2017-02-strongest ... -real.html

iopscience.iop.org/article/10.1088/1367-2630/aa54ab

… "There will always be wriggle room!" he said. "Certainly with the techniques known to us at the present time, a small amount of epistemic overlap can always be maintained, because experiments must be finished in a finite amount of time, and always suffer from a little bit of noise. That is to say nothing of the more wacky loopholes that a staunch epistemicist could try and jump through: for example, one can usually appeal to retrocausality or unfair sampling to get around the results of any 'experimental metaphysics.' Nevertheless, I believe that showing the quantum state must be at least 50% real is an achievable goal that most reasonable people would not be able to wriggle out of accepting." … [emphasis added]

… That being said, there is a good bit of controversy as to what the experiments actually show. Certain interpretations of quantum mechanics do claim that there is a metaphysical indeterminacy in the quantum world, e.g., the photon's nature is in fact indeterminate, while other interpretations argue for more modest epistemic conclusions, e.g., the intrinsic nature of the photon is in principle beyond our ken, even if we can estimate its current state within a range of probabilities. There are also issues as to what counts as "observation." Using the split screen experiment again, in this case observation is made by applying a laser beam to a photon stream. As far as we know, it is an open question as to whether the laser beam in fact interacts causally with the photon stream in a way that explains the experimental results without the need to posit an actual indeterminacy in the quantum world, though such interaction is as yet unknown to us. We will not weigh-in on these issues, not only because they go beyond our meager scientific pay grade, but because our view is that quantum indeterminacy, even under a strongly metaphysical interpretation, should really be taken as good news for the overall plausibility of hylomorphism! Let's stipulate then that, per the metaphysical interpretations of quantum indeterminacy, the intrinsic natures of the most fundamental physical elements are in-themselves in superpositional states with respect to certain incompatible attributes. That is, quantum particles, when separated from broader determinate systems suffer certain indeterminacies.

To see why this stipulation poses no problem for the hylomorphist, begin by remembering that the hylomorphist argues that matter, when considered in precision from its compositional role in a determinate substance, is indeterminate among a certain range physical attributes, even otherwise essential attributes. The intrinsic indeterminacy of matter to contraries is what provides the potency for the sorts of change substances can undergo at various levels of composition, e.g., the indeterminacy of Smitty between running and walking is what makes it possible for him to pick up the pace, or the indeterminacy of certain amino acids between the different types of muscle tissue is what makes eating meat a means for muscle growth for various types of animals. Moreover, the broader the compositional role of a certain kind of matter, i.e., the more types of substances that it can compose, the greater its range of intrinsic indeterminacies, and ultimately the hylomorphist claims all material beings are the beneficiaries of the universal indeterminacy of prime matter. Thus, the hylomorphist is not at all surprised to find that as more fundamental types of matter are discovered so too are greater levels of intrinsic indeterminacy. Indeed he or she should expect as much. In other words, the "closer" we come to prime matter, the more we expect proximate matter to resemble prime matter's indeterminacy. …