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Full Version: Human bias about reality is the real problem (philosophy of physics)
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https://www.forbes.com/sites/startswitha...870e4a6444

EXCERPT (Ethan Siegel): . . . For thousands of years, if you wanted to investigate the Universe in a scientific fashion, all you had to do was figure out the right physical conditions to set up, and then making the critical observations or measurements would give you the answer. [...] Until the end of the 19th century, all of our best physical theories describing the Universe followed this path. Why did nature appear to behave this way? Because the rules that governed it — our best theories that we had concocted to describe what we measure and observe — all obeyed the same sets of rules.

(1) The Universe is local, which means that an event or interaction can only affect its environment in a way that's limited by the speed limit of anything propagating through the Universe: the speed of light.
(2) The Universe is real, which means that certain physical quantities and properties (of particles, systems, fields, etc.) exist independent of any observer or measurements.
(3) The Universe is deterministic, which means that if you set your system up in one particular configuration, and you know that configuration exactly, you can perfectly predict what the state of your system is going to be an arbitrary amount of time into the future.

For more than a century, however, nature has shown us that the rules governing it aren't local, real, and deterministic after all. The quantum nature of the Universe tells us that certain quantities have an inherent uncertainty built into them, and that pairs of quantities have their uncertainties related to one another. There is no evidence for a more fundamental reality with hidden variables that underlies our observable, quantum Universe.

We learned what we know today about the Universe by asking the right questions, which means by setting up physical systems and then performing the necessary measurements and observations to determine what the Universe is doing. Despite what we might have intuited beforehand, the Universe showed us that the rules it obeys are bizarre, but consistent. The rules are just profoundly and fundamentally different from anything we'd ever seen before.

It wasn't so surprising that the Universe was made of indivisible, fundamental units: quanta, like quarks, electrons or photons. What was surprising is that these individual quanta didn't behave like Newton's particles: with well-defined positions, momenta, and angular momenta. Instead, these quanta behaved like waves — where you could compute probability distributions for their outcomes — but making a measurement would only ever give you one specific answer, and you can never predict which answer you'll get for an individual measurement.

[...] It seems only natural to ask what seems like a more fundamental question: what is really going on, objectively, behind-the-scenes, to explain what we observe in an observer-independent fashion? This is a question many have asked over the past 90 years (or so), attempting to obtain a deeper view of what's truly real. But despite many books and op-eds on the subject, from Lee Smolin to Sean Carroll to Adam Becker to Anil Ananthaswamy to many others, this might not even be a good question.

Smolin himself put it very bluntly during a public lecture he delivered less than a year ago: "A complete description should tell us what is happening in each individual process, independent of our knowledge, beliefs, or our interventions or interactions with the system."

In science, this is what we call an assumption, a postulate or an assertion. It sounds compelling, but it might not be true. The search for "a complete description" in this fashion assumes that nature can be described in an observer-independent or interaction-independent fashion, and this may not be the case. While Sean Carroll just argued in Sunday's New York Times that physicists should care more about (and spend more time and energy studying) these quantum foundations, most physicists — myself included — don't agree.

Reality, if you want to call it that, isn't some objective existence that goes beyond what's measurable or observable. In physics, as I've written before, describing what is observable and measurable in the most complete and accurate way possible is our loftiest aspiration. By devising a theory where quantum operators act on quantum wavefunctions, we gained the ability to accurately compute the probability distribution of whatever outcomes might possibly occur.

For most physicists, this is enough. But you can impose a set of assumptions atop these equations, and come up with a set of different interpretations of quantum mechanics [...] Carroll has just devised a sort-of-new interpretation himself, which is arguably just as interesting as (or no more interesting than) any of the others.

Frustratingly, all of these interpretations, plus others, are experimentally indistinguishable from one another. There is no experiment we have yet been able to design or perform that discerns one of these interpretations from another, and therefore they are physically identical. The idea that there is a fundamental, objective, observer-independent reality is an assumption with no evidence behind it, just thousands upon thousands of years of our intuition telling us "it should be so."

But science does not exist to show that reality conforms to our biases and prejudices and opinions; it seeks to uncover the nature of reality irrespective of our biases. If we really want to understand quantum mechanics, the goal should be more about letting go of our biases and embracing what the Universe tells us about itself. Instead, Carroll regressively campaigns for the opposite in teasing his upcoming new book. Unsurprisingly, most physicists are underwhelmed.

Understanding the Universe isn't about revealing a true reality, divorced from observers, measurements, and interactions. The Universe could exist in such a fashion where that's a valid approach, but it could equally be the case that reality is inextricably interwoven with the act of measurement, observation, and interaction at a fundamental level. [...] In science, it is not up to us to declare what reality is and then contort our observations and measurements to conform to our assumptions. [...] It's not a problem for physics that reality looks puzzling and bizarre; it's only a problem if you demand that the Universe deliver something beyond what reality provides.

There is a strange and wonderful reality out there, but until we devise an experiment that teaches us more than we presently know, it's better to embrace reality as we can measure it than to impose an additional structure driven by our own biases. Until we do that, we're superficially philosophizing about a matter where scientific intervention is required. Until we devise that key experiment, we'll all remain in the dark. (MORE - detailed elaboration)

RELATED: Why do interpretations of quantum physics matter?
I have an enormous amount of respect for the people who dedicate their lives to understanding the universe/reality. Most of us won’t or aren’t capable. I put myself in the latter category plus I can’t shake my skeptical attitude which tells me it may never happen. Maybe because we’re going in the wrong direction or that we’re not made for the long haul. IDK.

My description of reality would include the words mind boggling. Hard to imagine insignificant little clumps of organic matter understanding an enormous universe. You’d think more than that would be required but it’s all we have to work with. The secrets seem locked in things that are so small that to them our brains, nature’s D-I-Y computer and for all intents the mind’s repository, is like a universe in itself. So much of what we need to know seems to be contained in this ridiculously small area of our colossal universe. 

I hate waxing philosophic but to summarize: Colossus’ secrets will be revealed when the insignificant obtains complete knowledge of the ridiculously small. That’s how I see it. 

Can always hope some other life form in the universe has figured it out and if we’re lucky, get a chance to share with them that knowledge.