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Arthur T Knackerbracket has found the following story:
One of the most striking features of quantum theory is that its predictions are, under virtually all circumstances, probabilistic. If you set up an experiment in a laboratory, and then you use quantum theory to predict the outcomes of various measurements you might perform, the best the theory can offer is probabilities—say, a 50 percent chance that you'll get one outcome, and a 50 percent chance that you'll get a different one. The role the quantum state plays in the theory is to determine, or at least encode, these probabilities. If you know the quantum state, then you can compute the probability of getting any possible outcome to any possible experiment.
But does the quantum state ultimately represent some objective aspect of reality, or is it a way of characterizing something about us, namely, something about what some person knows about reality? This question stretches back to the earliest history of quantum theory, but has recently become an active topic again, inspiring a slew of new theoretical results and even some experimental tests.
If it is just your knowledge that changes, things don't seem so strange.
To see why the quantum state might represent what someone knows, consider another case where we use probabilities. Before your friend rolls a die, you guess what side will face up. If your friend rolls a standard six-sided die, you'd usually say there is about a 17 percent (or one in six) chance that you'll be right, whatever you guess. Here the probability represents something about you: your state of knowledge about the die. Let's say your back is turned while she rolls it, so that she sees the result—a six, say—but not you. As far as you are concerned, the outcome remains uncertain, even though she knows it. Probabilities that represent a person's uncertainty, even though there is some fact of the matter, are called epistemic, from one of the Greek words for knowledge.
This means that you and your friend could assign very different probabilities, without either of you being wrong. You say the probability of the die showing a six is 17 percent, whereas your friend, who has seen the outcome already, says that it is 100 percent. That is because each of you knows different things, and the probabilities are representations of your respective states of knowledge. The only incorrect assignments, in fact, would be ones that said there was no chance at all that the die showed a six.
-- submitted from IRC
(Score: 0) by Anonymous Coward on Wednesday May 03 2017, @02:04PM (23 children)
Every few decades we need to have these very same quantum soul searching pontificates. For 100 years the philosophers have been frustrated that they lost the "what is reality" podium to physicists; perhaps if they weren't so condescending towards mathematics and they actually took some of it, then they could have participated in the conversation.
(Score: 2) by melikamp on Wednesday May 03 2017, @03:26PM (7 children)
Their laziness goes quite beyond refusing to consider math. For more than half a century now they've had the late works of Wittgenstein (a mathematician by training, btw), where he explains in marvelous detail the folly of using the words such as "being" and "reality" in the sense employed in questions like "does the quantum state ultimately represent some objective aspect of reality?" I mean, he really chews it up for them in Philosophical Investigations, and then there are also Blue and Brown books, where he explains all the same things to an audience of Philosophy grad students (they need a special treatment because their brains are usually do badly damaged, they can't understand anything that doesn't use obscure Latin or lacks a reference to Kant on every page).
So short of learning some math and physics, they could have settled with an explanation of why they need to learn math and physics in order to escape the metaphysical swamp, where they all drown in the nebulous language they themselves created and insist on using. But few ever do. Many of them still flatly refuse to admit to a simple fact: the "reality" of which they want to speak is not bound by the grammar or semantics of their language. If anything, it is bound by the grammar or semantics of math, in as much as math applies to explaining physical phenomena, but definitely not by the ordinary language.
For example, one kind of difference between knowing and being is very well understood: think of the planet getting warmer versus Donald knowing it's getting warmer. The first scenario is described by the body of climate science done on the matter, and the latter scenario can be described by writing down what Donald says, or better yet, a brain scan. Put two climate scientists at the table, and they will have zero trouble discussing whether the planet is getting warmer, whether Donald is aware of it, and they will have no issue whatever in understanding these are two different things.
Closer to home, you can put two particle physicists at the table, and they will have zero trouble discussing the state of being of a photon (it manifests the properties of a wave and of a particle in different situations) versus the state of their knowledge about individual photons (they know they fly through a double-slit and create a wavy pattern on a sensor plate beyond).
(Score: 1, Funny) by Anonymous Coward on Wednesday May 03 2017, @06:09PM (2 children)
an audience of Philosophy grad students (they need a special treatment because their brains are usually do badly damaged, they can't understand anything that doesn't use obscure Latin or lacks a reference to Kant on every page).
Citation needed! Preferably one in Latin, or from Kant.
(Score: 2) by Azuma Hazuki on Thursday May 04 2017, @04:05AM (1 child)
"Fabricati diem, pvnc."
I am "that girl" your mother warned you about...
(Score: 1) by Demena on Sunday May 07 2017, @05:48AM
Really? ''Make the day"...
(Score: 1, Interesting) by Anonymous Coward on Wednesday May 03 2017, @06:14PM (3 children)
Could you be more specific on how you know that this:
in as much as math applies to explaining physical phenomena,
has any basis in reality whatsoever? And if you indeed claim to know this, please tell us just how much math applies to physical phenomena. I feel like we are working with an unknown margin of error, one that could approach 100%, or in the range of "massively mistaken".
(Score: 0) by Anonymous Coward on Wednesday May 03 2017, @06:35PM (1 child)
What are you getting at? We've got things like the Standard Model which describes the plethora of particles and their interaction strengths, all from fixing one free parameter (the electron mass). All of that is tied together with coupling constants calculable to a dozen or more significant digits that agree with experiment. The question has always been not IF mathematics describes the world around us, but WHY does it? Is mathematics a human construct? I don't understand the angle you are working from.
(Score: 0) by Anonymous Coward on Wednesday May 03 2017, @06:53PM
The question has always been not IF mathematics describes the world around us, but WHY does it?
Really!!! Here, talk to Morpheus, the god of dreams: "Have you ever had a dream that seemed so real that math actually described it? Do you think those are real integers you are breathing?" Your question used to be the question, but it no longer is. It has been recognized as unwarranted presumption.
(Score: 2) by melikamp on Wednesday May 03 2017, @06:56PM
I don't know whether the reality is mathematical, but it is at least conceivable that we live inside a mathematical structure. May be we are essentially AI agents inside a big computation, for example, and then the reality is actually mathematical, regardless of how the simulation is done, and regardless of whether we can grok what's going on. It is very easy to design mathematical universes where resident intelligent agents will be practically prevented from getting to the bottom of things, but we can also imagine a universe where it's quite possible. For example, if we live inside a von Neumann computer, we could hope one day to get access to the memory tape and the raw byte code, and figure out the instruction set. Or may be the universe is some kind of topological space, and we can discover the differential equations from which both gravity and quantum mechanical phenomena emerge with utmost certainty and accuracy.
And quite regardless, in many real-life instances we can totally quantify just how much math applies to natural phenomena. If we drop a golf ball near the surface of the Moon, it's going to follow Newton's laws of motion with mind-blowing accuracy. I don't want to compute the deviation from the GR in this case, but I will safely claim 99.9% accuracy there, probably quite a bit more, and GR itself likewise has been tested with amazing precision.
(Score: 2) by aristarchus on Wednesday May 03 2017, @06:06PM (14 children)
perhaps if they weren't so condescending towards mathematics
Who do you think invented math? Have you heard of Liebniz? Descartes? Pythagoras? Math is not the problem, unexamined metaphysical assumptions about math are the problem. As an American philosopher once said: "Those who do not know their history are condemned to be Mathematicians."
(See also: Πρὸς μαθηματικούς by Sextus Empiricus, 2nd Cent. C.E.)
(Score: 0) by Anonymous Coward on Wednesday May 03 2017, @06:28PM (3 children)
I know them, and others like Russel. But who fills all the hallowed halls of greater learning in the Philosophy departments? There aren't any mathematically inclined folk there (within rounding error).
(Score: 2) by aristarchus on Wednesday May 03 2017, @06:48PM (2 children)
Ah, you must be a very blissful person. By the way, the name is Lord Bertrand Russell, two "l"s. And a Mandatory XKCD [xkcd.com]
(Score: -1, Flamebait) by Anonymous Coward on Wednesday May 03 2017, @08:33PM (1 child)
You are the blissful one, my friend, if you think anything deemed a philosophical tome in the last 100 years has come from anyone with a rudimentary training in mathematics. What you've gotten was a handful of physicist popularizers making tenuous and speculative claims on theoretical physics, which get picked up by the likes of Fritjof Capra and bastardized and over-extrapolated into some kind of bullshit New Age crap. Meanwhile all the professors in the Philosophy Departments are struggling to separate themselves from the sociologists because they can't even begin to understand any of the physics of the last 100 years. Once the Special Relativity horse has been beaten to death (because you only have to understand what a square root is), they've all retreated into analysis of pre-20th century philosophers because that is where their "safe places" are.
(Score: 2) by melikamp on Wednesday May 03 2017, @08:53PM
(Score: 2) by melikamp on Wednesday May 03 2017, @07:18PM (2 children)
(Score: 2) by aristarchus on Wednesday May 03 2017, @10:30PM (1 child)
"Hilary Putnam is well known for his quasi-empiricism in mathematics," Unfortunately, he just passed.
And shirley you have heard of philosophers such as Donald Davidson, Daniel Dennett, Douglas Hofstadter, John Searle, And did I mention Quine and "Polymath, logician, mathematician, philosopher, and scientist Charles Sanders Peirce". It is all right there at the end of a Wikipedia search, which while not necessarily reliable (Wot? Ayn Rand as an American Philosopher? Ha ha ah!), is much better than your undergraduate biases.
(Score: 2) by melikamp on Thursday May 04 2017, @04:17AM
Oh man, reading Putnam article... I remember reading about this guy. Just the "argument for the reality of mathematical entities" would be enough, and I can't really read after that with a straight face, especially as sober as I am right now.
I actually read Searle and saw him talk at SJSU may be 10 years back, a very entertaining lecture, can't remember a single thing, it was a bit over my head... But I remember during the Q&A someone asked him about the Chinese Room, and Searle instantly got livid, like Robert Fripp these days when a fan asks him to play 21st CSM. There was a lot of yelling after that, but it can all be summed up as "I moved on, you haven't".
(Score: 1, Offtopic) by melikamp on Wednesday May 03 2017, @08:00PM (4 children)
(Score: 2) by melikamp on Thursday May 04 2017, @01:41AM (3 children)
(Score: 2) by aristarchus on Thursday May 04 2017, @03:17AM (2 children)
Cower in fear, you Sophist!
'Do not meddle in the affairs of wizards and philosophers, for they are subtle and quick to anger.'
But no, you did not offend, you just exposed your total ignorance of academic philosophy, which makes me think that perhaps that Philosophers need to do more public service and education. A bit of familiarity would make caricatures like yours rather impossible.
(Score: 2) by melikamp on Thursday May 04 2017, @03:39AM (1 child)
(Score: 2) by melikamp on Thursday May 04 2017, @03:44AM
(Score: 2) by maxwell demon on Wednesday May 03 2017, @10:48PM (1 child)
No. Was it the confused cousin of Leibniz? :-)
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by aristarchus on Wednesday May 03 2017, @11:33PM
"A Leibnitz? In Austria?"