trentmkelly/LessWrong-43k huggingface dataset:
Quantum Physics Revealed As Non-Mysterious
by Eliezer Yudkowsky — 2008-06-12T05:20:16.000Z

This is one of several shortened indices into the Quantum Physics Sequence.

Hello! You may have been directed to this page because you said
something along the lines of "Quantum physics shows that reality
doesn't exist apart from our observation of it," or "Science has
disproved the idea of an objective reality," or even just "Quantum
physics is one of the great mysteries of modern science; no one
understands how it works."

There was a time, roughly the first half-century after quantum
physics was invented, when this was more or less true. Certainly, when
quantum physics was just being discovered, scientists were very
confused indeed! But time passed, and science moved on. If you're
confused about a phenomenon, that's a fact about your own state of
mind, not a fact about the phenomenon itself - there are mysterious
questions, but not mysterious answers. Science eventually figured out
what was going on, and why things looked so strange at first.

The series of posts indexed below will show you - not just
tell you - what's really going on down there. To be honest, you're not
going to be able to follow this if algebra scares you. But there won't
be any calculus, either.

Some optional preliminaries you might want to read:

Reductionism: We build models of the universe that have many different levels of description. But so far as anyone has been able to determine, the universe itself has only the single level of fundamental physics - reality doesn't explicitly compute protons, only quarks.

Joy in the Merely Real:
If you can't take joy in things that turn out to be explicable, you're
going to set yourself up for eternal disappointment. Don't worry if
quantum physics turns out to be normal.

And here's the main sequence:

Quantum Explanations:
Quantum mechanics doesn't deserve its fearsome reputation. If you tell
people something is supposed to be mysterious, they won't understand
it. It's human intuitions that are "strange" or "weird"; physics
itself is perfectly normal. Talking about historical erroneous
concepts like "particles" or "waves" is just asking to confuse people;
present the real, unified quantum physics straight out.

Configurations and Amplitude:
A preliminary glimpse at the stuff reality is made of.

...
An Intuitive Explanation of Quantum Mechanics
by Eliezer Yudkowsky — 2008-06-12T03:45:56.000Z

This is one of several shortened indices into the Quantum Physics Sequence. It is intended for students who are having trouble grasping the meaning of quantum math; or for people who want to learn the simple math of everything and are getting around to quantum mechanics.

There's a widespread belief that quantum mechanics is supposed to be confusing. This is not a good frame of mind for either a teacher or a student. Complicated math can be difficult but it is never, ever allowed to be confusing.

And I find that legendarily "confusing" subjects often are not really all that complicated as math, particularly if you just want a very basic - but still mathematical - grasp on what goes on down there.

This series takes you as far into quantum mechanics as you can go with only algebra. Any further and you should get a real physics textbook - once you know what all the math means.

Quantum Explanations:
Quantum mechanics doesn't deserve its fearsome reputation. If you tell
people something is supposed to be mysterious, they won't understand
it. It's human intuitions that are "strange" or "weird"; physics
itself is perfectly normal. Talking about historical erroneous
concepts like "particles" or "waves" is just asking to confuse people;
present the real, unified quantum physics straight out. The series
will take a strictly realist perspective - quantum equations describe
something that is real and out there.

Configurations and Amplitude:
A preliminary glimpse at the stuff reality is made of. The classic
split-photon experiment with half-silvered mirrors. Alternative
pathways the photon can take, can cancel each other out. The
mysterious measuring tool that tells us the relative squared moduli.

Joint Configurations:
The laws of physics are inherently over mathematical entities,
configurations, that involve multiple particles. A basic,
ontologically existent entity, according to our current understanding
of quantum mechanics, does not look like a photon - it looks like a
configuration of the universe with "A photon here, a photon there."
Amplitude flows between these configurations can cancel or add; this
gives us a way to detect which configurations are distinct.

Distinct Configurations:
Since configurations are over the combined state

...
The Quantum Physics Sequence
by Eliezer Yudkowsky — 2008-06-11T03:42:14.000Z

This is an inclusive guide to the series of posts on quantum mechanics that began on April 9th, 2008, including the digressions into related topics (such as the difference between Science and Bayesianism) and some of the preliminary reading.

You may also be interested in one of the less inclusive post guides, such as:

An Intuitive Explanation of Quantum Mechanics (just the science, for students confused by their physics textbooks)

Quantum Physics Revealed As Non-Mysterious (quantum physics does not make the universe any more mysterious than it was previously)

And the Winner is... Many-Worlds! (the many-worlds interpretation wins outright given the current state of evidence)

Quantum Mechanics and Personal Identity (the ontology of quantum mechanics, in which there are no particles with individual identities, rules out theories of personal continuity that invoke "the same atoms" as a concept)

My current plan calls for the quantum physics series to eventually be turned into one or more e-books.

Preliminaries:

Probability is in the Mind: If you are uncertain about a phenomenon, this is a fact about your state of mind, not a fact about the phenomenon itself. There are mysterious questions but not mysterious answers. The map is not the territory.

Reductionism: We build models of the universe that have many different levels of description. But so far as anyone has been able to determine, the universe itself has only the single level of fundamental physics - reality doesn't explicitly compute protons, only quarks.

Joy in the Merely Real: If you can't take joy in things that turn out to be explicable, you're going to set yourself up for eternal disappointment. Don't worry if quantum physics turns out to be normal.

Zombies! Zombies? and The Generalized Anti-Zombie Principle: Don't try to put your consciousness or your personal identity outside physics. Whatever makes you say "I think therefore I am", causes your lips to move; it is within the chains of cause and effect that produce our observed universe.

Belief in the Implied Invisible: If a spaceship goes over the cosmological horizon relative to us, so that it can no longer communicate with us, should we believe that the spaceship instantly ceases to exist?

Basic Quantum Mechanics:

Quantum Explanations: Quantum mechanics doesn't deserve its fe

...
Eliezer's Post Dependencies; Book Notification; Graphic Designer Wanted
by Eliezer Yudkowsky — 2008-06-10T01:18:14.000Z

I'm going to try and produce summaries of the quantum physics series today or tomorrow.

Andrew Hay has produced a neat graph of (explicit) dependencies among my Overcoming Bias posts - an automatically generated map of the "Followup to" structure:

Eliezer's Post Dependencies (includes only posts with dependencies)
All of my posts (including posts without dependencies)

Subscribe here to future email notifications for when the popular book comes out (which may be a year or two later), and/or I start producing e-books:

Notifications for the rationality book, or for any other stuff I produce

(Thanks to Christian Rovner for setting up PHPList.)

Sometime in the next two weeks, I need to get at least one Powerpoint presentation of mine re-produced to professional standards of graphic design. Ideally, in a form that will let me make small modifications myself. This is likely to lead into other graphic design work on producing the ebooks, redesigning my personal website, creating Bayesian Conspiracy T-shirts, etc.

I am not looking for an unpaid volunteer. I am looking for a professional graphic designer
who can do sporadic small units of work quickly.

Desired
style for the presentation: Professional-looking and easy-to-read (as opposed to flamboyant /
elaborate). I already have the presentation content, in black text on white background. I would like it to look like it was produced by a grownup, which is beyond my own skill. Emails to sentience@pobox.com, please include your fee schedule and a link to your portfolio.
Against Devil's Advocacy
by Eliezer Yudkowsky — 2008-06-09T04:15:29.000Z

From an article by Michael Ruse:

Richard Dawkins once called me a "creep." He did so very publicly but meant no personal offense, and I took none: We were, and still are, friends. The cause of his ire—his anguish, even—was that, in the course of a public discussion, I was defending a position I did not truly hold. We philosophers are always doing this; it's a version of the reductio ad absurdum argument. We do so partly to stimulate debate (especially in the classroom), partly to see how far a position can be pushed before it collapses (and why the collapse), and partly (let us be frank) out of sheer bloody-mindedness, because we like to rile the opposition.

Dawkins, however, has the moral purity—some would say the moral rigidity—of the evangelical Christian or the committed feminist. Not even for the sake of argument can he endorse something that he thinks false. To do so is not just mistaken, he feels; in some deep sense, it is wrong. Life is serious, and there are evils to be fought. There must be no compromise or equivocation, even for pedagogical reasons. As the Quakers say, "Let your yea be yea, and your nay, nay."

Michael Ruse doesn't get it.

When I was a kid and my father was teaching me about skepticism -

(Dad was an avid skeptic and Martin Gardner / James Randi fan, as well as being an Orthodox Jew. Let that be a lesson on the anti-healing power of compartmentalization.)

- he used the example of the hypothesis: "There is an object one foot across in the asteroid belt composed entirely of chocolate cake." You would have to search the whole asteroid belt to disprove this hypothesis. But though this hypothesis is very hard to disprove, there aren't good arguments for it.

And the child-Eliezer asked his mind to search for arguments that there was a chocolate cake in the asteroid belt. Lo, his mind returned the reply: "Since the asteroid-belt-chocolate-cake is one of the classic examples of a bad hypothesis, if anyone ever invents a time machine, some prankster will toss a chocolate cake back into the 20th-century asteroid belt, making it true all along."

Thus - at a very young age - I discovered that my mind could, if asked, invent arguments for anything.

I know people whose sanity has been destroyed by this discovery. They conclude that Reason can be used to argue for anything.&...
Bloggingheads: Yudkowsky and Horgan
by Eliezer Yudkowsky — 2008-06-07T22:09:00.000Z

I appear today on Bloggingheads.tv, in "Science Saturday: Singularity Edition", speaking with John Horgan about the Singularity. I talked too much. This episode needed to be around two hours longer.

One question I fumbled at 62:30 was "What's the strongest opposition you've seen to Singularity ideas?" The basic problem is that nearly everyone who attacks the Singularity is either completely unacquainted with the existing thinking, or they attack Kurzweil, and in any case it's more a collection of disconnected broadsides (often mostly ad hominem) than a coherent criticism. There's no equivalent in Singularity studies of Richard Jones's critique of nanotechnology - which I don't agree with, but at least Jones has read Drexler. People who don't buy the Singularity don't put in the time and hard work to criticize it properly.

What I should have done, though, was interpreted the question more charitably as "What's the strongest opposition to strong AI or transhumanism?" in which case there's Sir Roger Penrose, Jaron Lanier, Leon Kass, and many others. None of these are good arguments - or I would have to accept them! - but at least they are painstakingly crafted arguments, and something like organized opposition.
Timeless Control
by Eliezer Yudkowsky — 2008-06-07T05:16:48.000Z

Followup to: Timeless Physics, Timeless Causality, Thou Art Physics

People hear about many-worlds, which is deterministic, or about timeless physics, and ask:

If the future is determined by physics, how can anyone control it?

In Thou Art Physics, I pointed out that since you are within physics, anything you control is necessarily controlled by physics. Today we will talk about a different aspect of the confusion, the words "determined" and "control".

The "Block Universe" is the classical term for the universe considered from outside Time. Even without timeless physics, Special Relativity outlaws any global space of simultaneity, which is widely believed to suggest the Block Universe—spacetime as one vast 4D block.

When you take a perspective outside time, you have to be careful not to let your old, timeful intuitions run wild in the absence of their subject matter.

In the Block Universe, the future is not determined before you make your choice. "Before" is a timeful word. Once you descend so far as to start talking about time, then, of course, the future comes "after" the past, not "before" it.

If we're going to take a timeless perspective, then the past and the future have not always been there. The Block Universe is not something that hangs, motionless and static, lasting for a very long time. You might try to visualize the Block Universe hanging in front of your mind's eye, but then your mind's eye is running the clock while the universe stays still. Nor does the Block Universe exist for just a single second, and then disappear. It is not instantaneous. It is not eternal. It does not last for exactly 15 seconds. All these are timeful statements. The Block Universe is simply there.

Perhaps people imagine a Determinator—not so much an agent, perhaps, but a mysterious entity labeled "Determinism"—which, at "the dawn of time", say, 6:00am, writes down your choice at 7:00am, and separately, writes the outcome at 7:02am. In which case, indeed, the future would be determined before you made your decision...

In this model, the Determinator writes the script for the Block Universe at 6:00am. And then time—the global time of the universe—continues, running through the Block Universe and realizing the script.

At 7:00am you're trying to decide to turn on the...
Thou Art Physics
by Eliezer Yudkowsky — 2008-06-06T06:37:01.000Z

Three months ago—jeebers, has it really been that long?—I posed the following homework assignment: Do a stack trace of the human cognitive algorithms that produce debates about “free will.” Note that this task is strongly distinguished from arguing that free will does or does not exist.

Now, as expected, people are asking, “If the future is determined, how can our choices control it?” The wise reader can guess that it all adds up to normality; but this leaves the question of how.

People hear: “The universe runs like clockwork; physics is deterministic; the future is fixed.” And their minds form a causal network that looks like this:

Here we see the causes “Me” and “Physics,” competing to determine the state of the “Future” effect. If the “Future” is fully determined by “Physics,” then obviously there is no room for it to be affected by “Me.”

This causal network is not an explicit philosophical belief. It’s implicit— a background representation of the brain, controlling which philosophical arguments seem “reasonable.” It just seems like the way things are.

Every now and then, another neuroscience press release appears, claiming that, because researchers used an fMRI to spot the brain doing something-or-other during a decision process, it’s not you who chooses, it’s your brain.

Likewise that old chestnut, “Reductionism undermines rationality itself. Because then, every time you said something, it wouldn’t be the result of reasoning about the evidence—it would be merely quarks bopping around.”

Of course the actual diagram should be:

Or better yet:

Why is this not obvious? Because there are many levels of organization that separate our models of our thoughts—our emotions, our beliefs, our agonizing indecisions, and our final choices—from our models of electrons and quarks.

We can intuitively visualize that a hand is made of fingers (and thumb and palm). To ask whether it’s really our hand that picks something up, or merely our fingers, thumb, and palm, is transparently a wrong question.

But the gap between physics and cognition cannot be crossed by direct visualization. No one can visualize atoms making up a person, the way they can see fingers m...
Living in Many Worlds
by Eliezer Yudkowsky — 2008-06-05T02:24:05.000Z

Some commenters have recently expressed disturbance at the thought of constantly splitting into zillions of other people, as is the straightforward and unavoidable prediction of quantum mechanics.

Others have confessed themselves unclear as to the implications of many-worlds for planning: If you decide to buckle your seat belt in this world, does that increase the chance of another self unbuckling their seat belt? Are you being selfish at their expense?

Just remember Egan’s Law: It all adds up to normality.

(After Greg Egan, in Quarantine.[1])

Frank Sulloway said [2]:

Ironically, psychoanalysis has it over Darwinism precisely because its predictions are so outlandish and its explanations are so counterintuitive that we think, Is that really true? How radical! Freud’s ideas are so intriguing that people are willing to pay for them, while one of the great disadvantages of Darwinism is that we feel we know it already, because, in a sense, we do.

When Einstein overthrew the Newtonian version of gravity, apples didn’t stop falling, planets didn’t swerve into the Sun. Every new theory of physics must capture the successful predictions of the old theory it displaced; it should predict that the sky will be blue, rather than green.

So don’t think that many-worlds is there to make strange, radical, exciting predictions. It all adds up to normality.

Then why should anyone care?

Because there was once asked the question, fascinating unto a rationalist: What all adds up to normality?

And the answer to this question turns out to be: quantum mechanics. It is quantum mechanics that adds up to normality.

If there were something else there instead of quantum mechanics, then the world would look strange and unusual.

Bear this in mind, when you are wondering how to live in the strange new universe of many worlds: You have always been there.

Religions, anthropologists tell us, usually exhibit a property called minimal counterintuitiveness; they are startling enough to be memorable, but not so bizarre as to be difficult to memorize. Anubis has the head of a dog, which makes him memorable, but the rest of him is the body of a man. Spirits can see through walls; but they still become hungry.

But physics is not a religion, set to surprise you just exactly enough to be memorable. The underlying phenomena are so counterintuitive that it takes long study for humans to come to grips with them. But th...
Why Quantum?
by Eliezer Yudkowsky — 2008-06-04T05:34:01.000Z

This post is part of the Quantum Physics Sequence.
Followup to: Quantum Explanations

"Why are you doing these posts on quantum physics?" the one asked me.

"Quite a number of reasons," I said.

"For one thing," I said, "the many-worlds issue is just about the only case I know of where you can bring the principles of Science and Bayesianism into direct conflict." It's important to have different mental buckets for "science" and "rationality", as they are different concepts. Bringing the two principles into direct conflict is helpful for illustrating what science is and is not, and what rationality is and is not. Otherwise you end up trusting in what you call "science", which won't be strict enough.

"For another thing," I continued, "part of what goes into becoming a rationalist, is learning to live into a counterintuitive world—learning to find things underneath the surface that are unlike the world of surface forms." Quantum mechanics makes a good introduction to that, when done correctly without the horrible confusion and despair. It breaks you of your belief in an intuitive universe, counters naive realism, destroys your trust in the way that your cognitive algorithms look from inside—and then you're ready to start seeing your mind as a mind, not as a window onto reality.

"But you're writing about physics, without being a physicist," the one said, "isn't that... a little..."

"Yes," I said, "it is, and I felt guilty about it. But there were physicists talking complete nonsense about Occam's Razor without knowing the probability theory of it, so my hand was forced. Also the situation in teaching quantum mechanics is really awful—I saw the introductions to Bayesianism and they seemed unnecessarily difficult, but the situation in quantum mechanics is so much worse." It really is. I remember sitting there staring at the "linear operators", trying to figure out what the hell they physically did to the eigenvectors—trying to visualize the actual events that were going on in the physical evolution—before it dawned on me that it was just a math trick to extract the average of the eigenvalues. Okay, but... can't you just tell me that up front? Write it down somewhere? Oh, I forgot, the math doesn't mean anything, it just works.

"Furthermore," I added, "knowing about many wor...
Timeless Identity
by Eliezer Yudkowsky — 2008-06-03T08:16:33.000Z

Followup to: No Individual Particles, Identity Isn't In Specific Atoms, Timeless Physics, Timeless Causality

People have asked me, "What practical good does it do to discuss quantum physics or consciousness or zombies or personal identity? I mean, what's the application for me in real life?"

Before the end of today's post, we shall see a real-world application with practical consequences, for you, yes, you in today's world. It is built upon many prerequisites and deep foundations; you will not be able to tell others what you have seen, though you may (or may not) want desperately to tell them. (Short of having them read the last several months of OB.)

In No Individual Particles we saw that the intuitive conception of reality as little billiard balls bopping around, is entirely and absolutely wrong; the basic ontological reality, to the best of anyone's present knowledge, is a joint configuration space. These configurations have mathematical identities like "A particle here, a particle there", rather than "particle 1 here, particle 2 there" and the difference is experimentally testable. What might appear to be a little billiard ball, like an electron caught in a trap, is actually a multiplicative factor in a wavefunction that happens to approximately factor. The factorization of 18 includes two factors of 3, not one factor of 3, but this doesn't mean the two 3s have separate individual identities—quantum mechanics is sort of like that. (If that didn't make any sense to you, sorry; you need to have followed the series on quantum physics.)

In Identity Isn't In Specific Atoms, we took this counterintuitive truth of physical ontology, and proceeded to kick hell out of an intuitive concept of personal identity that depends on being made of the "same atoms"—the intuition that you are the same person, if you are made out of the same pieces. But because the brain doesn't repeat its exact state (let alone the whole universe), the joint configuration space which underlies you, is nonoverlapping from one fraction of a second to the next. Or even from one Planck interval to the next. I.e., "you" of now and "you" of one second later do not have in common any ontologically basic elements with a shared persistent identity.

Just from standard quantum mechanics, we can see immediately that some of the st...