Pillar of Science V: Ethical Integrity

by Aron Wall Posted on November 21, 2012

Scientists must have Integrity.

Because Science involves an ethical principle, the love of truth, its practice cannot be unmoored from principles of morality.  A hypothesis can only be put to a fair test by a person who prefers knowing the truth even if it shows that their previous position was wrong (a corollary is that science becomes unreliable when there is political pressure to come to particular conclusions, such as the Lysenkoist biology mandated by Stalin, or the Deutschephysik of Nazi Germany).

This virtue is sometimes referred to as “objectivity”, but this word suggests a sort of dispassionate neutrality which is not actually characteristic of most real scientists—we actually tend to get rather excited about our work, or we wouldn't be doing it.  A better term for this virtue is humility: when doing research the scientist must take the posture towards the universe of a learner, rather than a teacher.  Unfortunately, some effective scientists are conceited and arrogant towards their peers, but when scientists take the same attitude towards Nature, they continue to defend ideas long after they become discredited, and become useless to Science.

It's also extremely common for working scientists to get mailings from laypersons who believe themselves to have revolutionized large areas of science, despite having imprecise, untested, and often meaningless ideas.  This psychotic disconnect from reality is nearly always accompanied by severe egoism, showing by contrast the way that humility characterizes true science.

Of course, humility does not involve taking the view that all knowledge is unreliable and tentative, since this would actually inhibit the discovery of truth!  (In modern times, revolutions in Science usually do not totally invalidate our previous understandings; instead the previous theories survive as approximations.)  The proper attitude of a learner is: “Test everything; hold onto what is good” (1 Thessalonians 5:21).

A second virtue of science is honesty.  Scientists must refrain from fudging results or misleading other scientists.  Honesty requires noting the factors weighing against a conclusion as well as those weighing for it.  They must also take precautions against bias, not in the sense of being unbiased (none of us are), but preventing that bias from contaminating their results.  Hence the need for experimentalists to do proper error analysis, use control groups, double-blind tests, etc.  Experiments that show the absence of an effect should be published as well as experiments that show the presence of an effect, even if such results are less likely to result in fame and respect.

I was going to include some juicy long excerpt from Feynman's famous commencement address on "Cargo Cult Science".  But too much of it was relevant to what I'm saying!  You should just go and read the whole thing.

Posted in Scientific Method | Leave a comment

The Numinous

by Aron Wall Posted on November 18, 2012

A few weeks ago I started to describe what holiness means, and someone requested that I go into more detail.

One way to approach this is through the concept of the numinous, described in the classic work The Idea of the Holy by the Blessed Rudolf Otto.  This book was a significant influence on St. Lewis, who discusses the numinous especially in his introduction to The Problem of Pain.  The concept of the numinous is difficult to explain because most of the language we use to describe it has come to mean other things.  In English, the words "awesome" and "awful" both used to mean the same thing: the feeling of dread, wonder, uncanniness, terror, or reverence one gets in the presence of something you believe to be eerie or supernatural.  As Lewis points out, we use the same word "afraid" when we say that someone is a jungle is "afraid of tigers" as that someone in a haunted house is "afraid of ghosts".  But in the first case, the fear is just for our own safety, whereas in the case of ghosts one is afraid of what the ghost IS, more than what it will do to you.

Please note, I am not claiming that ghosts exist, but rather using them as an example to make a point about human psychology.  Just as we have a sexual instinct which responds to sexual stimuli, so we have another instinct which responds when we believe we are encountering supernatural stimuli.  The hairs stand up on the back of our neck and we feel chilly.  In that sense it feels like fear, even though the experience may be pleasant or unpleasant, and we may or may not be concerned for our physical safety.  Atheists, pagans, and Christians all experience this feeling on certain occasions; the difference is how they interpret it.

In our own minds, we can feel numinous feelings without making any connection to ethical concepts; a pagan or a pantheist may feel that they are worshiping a Spirit which is beyond human notions of good or evil.  However, when ethical concepts do intrude, a special composite feeling arises.  In the case where the object is perceived as Numinous Evil, we call the feeling that arises in us Horror.  This feeling can be excited by natural objects which seem "eerie" such as corpses or creepy insects.  (Lewis claims that there is no survival advantage in this feeling, but it seems to me that avoiding diseased corpses and dangerous insects may well have evolutionary advantage.)  It can also be excited when we read or watch movies about vampires, werewolves, demons etc.  (This assumes that the movies treat the topic seriously, of course.  Monsters that think and act just like regular people are humorous, since we expected a numinous thrill and then it was a false alarm).

When the object is perceived as Numinous Good, this composite idea is nothing other than the Holy.  (Unfortunately, there's a lack of grammatical parallelism here, in that "Holy" refers to the Object about which we have numinous feelings, whereas "Horror" refers to the feelings themselves.)  The distinctive characteristic of holiness is that ethics itself becomes imbued with supernatural significance.  This experience is not always happy.  As the classic example, consider Isaiah chapter 6:

In the year that King Uzziah died, I saw the Lord seated on a throne, high and exalted, and the train of his robe filled the temple. 2 Above him were seraphs [burning ones], each with six wings: With two wings they covered their faces, with two they covered their feet, and with two they were flying. 3 And they were calling to one another:

“Holy, holy, holy is YHWH of hosts;
the whole earth is full of his glory.”

4 At the sound of their voices the doorposts and thresholds shook and the temple was filled with smoke.

5 “Woe to me!” I cried. “I am ruined! For I am a man of unclean lips, and I live among a people of unclean lips, and my eyes have seen the King, YHWH of hosts.”

6 Then one of the seraphs flew to me with a live coal in his hand, which he had taken with tongs from the altar. 7 With it he touched my mouth and said, “See, this has touched your lips; your guilt is taken away and your sin atoned for.”

8 Then I heard the voice of the Lord saying, “Whom shall I send? And who will go for us?”  And I said, “Here am I. Send me!”

If you are a nonreligious person, I hope you tried to read that as you would some passage in a fantasy novel, with "suspension of disbelief".  Put aside how you feel about Christianity in general, and just ask how this passage makes you feel, as if it were a fictional work of art.

Doubtless Isaiah knew beforehand that he had ethical shortcomings; perhaps he lied, or berated someone.  But before, it was a matter of merely personal regret, excused by the fact that everyone does it.  In the presence of this astounding vision, his guilt becomes something completely different: a feeling of uncleanness and shrinking before a majestic purity, that even the angels had to hide their faces from.  It was like coming into a formal dinner party stinking, and wearing no clothes at all.

This is a numinous problem, not just an ethical problem.  So it needs a numinous solution.  The coal from the altar makes "atonement" for Isaiah's uncleanness.  That is, it allows Isaiah to become a participant in the numinous, in a way that covers up or removes his guilt.  Only then can St. Isaiah hear God's call to be a prophet, denouncing the sins of others.

It's a mistake to try to argue that Christianity is true before the audience knows what Christianity is.  Before people can understand Christianity, they have to understand the basic concepts in which it is expressed.  Without the concept of holiness, nothing we say about God deserving worship, or about Jesus dying on the cross for our sins, or about love requiring purity—none of it makes any sense at all!

Posted in Theology | 1 Comment

Firewalls

by Aron Wall Posted on November 17, 2012

There's been a huge kerfuffle in the quantum gravity community since this summer, when some people here at UCSB published a paper arguing that (old enough) black holes may actually be surrounded by a wall of fire which burns people up when they cross the event horizon.  This is huge, because if it were true it would upset everything we thought we knew about black holes.

General relativity is our best theory of gravity to date, discovered by Einstein.  This is a  classical theory.  (In the secret code that we physicists use, classical is our code-word for "doesn't take into account quantum mechanics".  Don't tell anyone I told you.)

In my other posts on physics, I've been trying to explain the fundamentals of physics in the minimum number of blog posts.  This post is out of sequence, since I haven't described general relativity yet!  But I wanted to say something about exciting current events.

In classical general relativity, a black hole is a region of space where the gravity is so strong that not even light can escape.  They tend to form at the center of galaxies, and from the collapse of sufficiently large stars when they run out of fuel to hold them up.  A black hole has an event horizon, which is the surface beyond which if you fall in, you can't ever escape without travelling faster than light. The information of anything falling into the black hole is lost forever, at least in classical physics.

In the case of a non-rotating black hole, without anything falling into it, the event horizon is a perfect sphere.  (If the black hole is rotating, it bulges out at the equator.)  If you fall past the event horizon, you will inevitably fall towards the center, just as in ordinary places you inevitably move towards the future.

At the center is the singularity.  As you approach the singularity, you get stretched out infinitely in one direction of space, and squashed to zero size in the other two directions of space, and then at the singularity time comes to an end!  Actually, just before time comes to an end, we know that the theory is wrong, since things get compressed to such tiny distances that we really ought to take quantum mechanics into account.  Since we don't have a satisfactory theory of quantum gravity yet, we don't really know for sure what happens.

Now it's important to realize that the event horizon is not a physical object.  Nothing strange happens there.  It's just an imaginary line between the place where you can get out by accelerating really hard, and the place where you can never get out.  Someone falling into the black hole just sees a vacuum.  If the black hole was formed from the collapse of a star, the matter from the star quickly falls into the singularity and disappears.  The black hole is empty inside, except for the gravitational field itself.

We don't know how to describe full-blown quantum gravity, but we have something called semiclassical gravity which is supposed to work well when the gravitational effects of the quantum fields are small.  In semiclassical gravity, one finds that black holes slowly lose energy from thermal "Hawking" radiation.  This radiation looks exactly like the random "blackbody radiation" coming from an ordinary object when you heat it up. Here's the important fact: You can prove that the radiation is thermal (i.e. random) just using the fact that someone falling across the horizon sees a vacuum (i.e. empty space) there.

The Hawking radiation comes from just outside the event horizon.  It does not come from inside the black hole, so in Hawking's original calculation it doesn't carry any information out from the inside.   Nevertheless, for various reasons I can't go into right now, most black hole physicists have convinced themselves that the information eventually does come out.

As the black hole radiates into space, it slowly evaporates, and eventually probably disappears entirely (although knowing what happens at the very end requires full-blown quantum gravity).  If the outgoing Hawking radiation carries all the radiation out, then for a black hole at a late enough stage in its evaporation, the radiation must not be completely random, because it actually encodes all the information about what fell in.

The gist of what Almheiri, Marolf, Polchinski, and Sully argued, is that if we take both of these statements in bold seriously, then it follows that the black holes are NOT in the vacuum state from the perspective of someone who falls in.  Instead you would get incinerated by a "firewall" as you cross the horizon.  (It's not clear yet whether this is only for really old black holes, or if it applies to younger ones too.)  That's if we still believe there is an "inside" at all.  The argument shows that semiclassical gravity is completely wrong in situations where we would have expected it to work great.

If this is right, then it's devastating to the ideas of many of us who have been thinking about black holes for a long time.  As a reluctant convert to the idea that information is not lost, I'm wondering if I should reconsider.  At the end of this month, I'm going to Stanford for a weekend, since Lenny Susskind has invited a bunch of us to try to get this worked out.  Exciting times!

 

Posted in Physics | 9 Comments

Pillar of Science IV: Precise Descriptions

by Aron Wall Posted on November 15, 2012

Science involves Precise Description.

To be capable of being confirmed or ruled out at the high levels of reliability associated with Science, a hypothesis must be stated in a way which is precise enough to do definitive tests.  Even if a scientific hypothesis may not be experimentally testable at the present time, a precise formulation helps indicate ways that it could be tested in the future.  If experiment is capable of making everyone eventually agree on whether the idea worked or not, then the words it is expressed in shouldn't mean different things to different people.

Mathematical models of the physical world are the most precise form of description available, because they can describe complicated systems with perfect exactitude.  In theoretical physics, this kind of quantitative description is the usual way to make things precise.  We like to think about systems that are simple enough to describe mathematically (of course, this requires first making certain approximations).  In fact, fundamental physics is so mathematical that, even when there are no or few experiments, one can often make progress just by demanding that the model be logically consistent, and that it conform to known physical principles.  (Known, because they have been tested in other situations where we can do experiments.)  Mathematical consistency is nearly our only guide in speculative fields like my own (quantum gravity); however, it cannot completely substitute for observations, since no matter how consistent or beautiful your model is, Nature could always do something else when you finally are able to take a look.

So Math is great when you can get it.  Nevertheless, systems which are less regular, more complex, or less well-understood (such as biological life) cannot always be described mathematically, but may still be described through technical vocabulary that minimizes imprecision, without removing it altogether.  I'm not a biologist, so I'm probably not the best person to ask how this usually works, but I didn't want to give the impression that math is the only way to make ideas precise.  Even in physics, at one time it was possible to describe everything in words.  The great experimenter St. Faraday (whose work helped established the concept of the electromagnetic field), once wrote a letter to St. Maxwell (who wrote down the equations for electromagnetism) expressing surprise at Maxwell's need to translate everything into mathematical equations.  Yet no one could accuse Faraday's journals of being imprecise.

But not all concepts will do.  Ideas that are apprehended in words or images rich with heavy associations or mottled with variegated meanings—in short, using the common language of humanity—such ideas are excluded from Science.  Not because it is impossible to discuss and test these ideas; if that were true, then it would be impossible to think accurately at all about most matters of ordinary human concern.  Rather, it is because they involve elements of human and holistic judgement which are unsuitable for scientific inquiry.  The question “Is xenophobia a frequent cause of war?” could be given an informed and accurate answer by a historian, but it does not become a scientific question until the terms “xenophobia”, “frequent”, and “war” are given technical meanings sufficiently precise that a social scientist can do a statistical analysis.

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Medieval Bashing

by Aron Wall Posted on November 12, 2012

Recently I ran across a pretty good explanation of the Higgs mechanism (hat tip Siris) by a certain Rob Knopp, which I thought I'd link to because of its connection with my previous post on fields.  When I first looked at his blog, it seemed like maybe I'd found a kindred spirit: someone who blogs on science while identifying as Christian.  Unfortunately, it turns out he actually denies almost all traditional Christian beliefs.  On this blog, religion won't mean something watered down until it makes few if any factual claims.  Instead I adhere to the red-hot supernaturalist "original brand" of Christianity that includes real miracles, a divine Incarnation, Atonement, inspired Scripture (including the Old Testament), the Second Coming, etc.  Just in case you were wondering.

However, what really stood out to me from the last link was this throwaway line about medieval culture:

[Jesus] lived an errant life, eschewing the temporal power that monarchs would later claim was justified by the "divine right of kings," even eschewing extreme temporal influence.  He preached the opposite of a lot of medieval social philosophy: the poor are not lesser humans and thus worthy of their lot, but if anything exalted. (Blessed are the poor, and all of that.)

Assuming that this was meant as a criticism of Medieval Europe (and not, say, the caste system of Medieval India), this is almost as far off base as if he said that Medievals had landed on the Moon.  The Medievals did not believe that the poor are "lesser humans and thus worthy of their lot".  It would be much more accurate to say that they believed that the poor were superior humans and that poverty is, not indeed strictly necessary for salvation, but highly desirable for anyone wanting to live more spiritually.  Which explains all those people who swore vows of poverty in order to live in monasteries.  It's almost as though they were familiar with the teachings of Jesus on the subject of poverty!

It's true that Medieval Europeans believed that the rule of earthly Kings was ordained by God.  But the claim that so-and-so was the rightful King of England originally had nothing whatsoever to do with spiritual superiority, any more than your claim to own your car, or the President's claim to be legitimately elected, implies any notion of being spiritually superior to other people.  Medieval Christians (like Ancient and Modern Christians) believed that God has ordained the existence of human governments to enforce justice, and that therefore (barring exceptional circumstances) it is our duty to obey whatever government one happens to live under.  There was indeed a much more extreme theory of the "divine right of kings" that basically said that the monarch could not be resisted under any circumstances whatsoever.  However, this theory was popular, not in Medieval times, but rather the Early Modern era (roughly the 16th-18th centuries).

As St. Chesterton pointed out, people are happy to accuse almost anything that seems old and bad as "Medieval" without checking to see what Medieval people actually thought and did.  In reality, prior to the Renaissance, the Medievals:

  • invented Academia as we know it, and founded the first Universities,
  • strongly believed that one could discover the nature of the Universe using logical reasoning based on appropriate authorities,
  • held in high regard ancient pagan learning and culture,
  • like all educated people after Aristotle, knew the Earth is spherical and that the universe is huge compared to the Earth,
  • prohibited military attacks on civilians, and tried to restrict war to certain days,
  • ended nearly all chattel slavery in Europe (but see below),
  • developed the notion that government must respect certain human rights (in feudalism, serfs were tied to the land but had customary rights which the lord was required to respect),
  • officially taught that witchcraft was impossible, and that the popular belief in witches was a superstition to be discouraged.

Yes, you heard that right.  They didn't burn witches.  They did burn heretics, but those were real whereas witches were a figment of the peasants' imagination.  Witch trials didn't become popular until the supposedly more enlightened Renaissance and Early Modern Era (mainly 1484-1750).  Even then they didn't burn witches, they hung them.  (What about all that stuff about dumping the witch in water to see if she floats?  You know, either she floats and is convicted, or she drowns and is posthumously acquitted.  Of course, no one would actually be so stupid as to devise a trial system that kills the innocent on purpose.  In reality, the witch-hunters would pull those who sank out of the water before they drowned.)

The early Medievals did occasionally use trial by ordeal, when the evidence of guilt was doubtful—for other crimes than witchcraft, which they didn't believe in, remember!  However, the trials actually appear to have been rigged to produce acquittals.  In any case, these mostly ended soon after 1215 when the Church refused to allow priests to cooperate.  In England this method was replaced with trial by jury.

The Modern Period also brought the racist version of the slave-trade into the world.  Unfortunately, because of failure to turn the other cheek when pagans or Muslims would capture Christians as slaves, some slavery of non-Christians was permitted.  Unfortunately, this meant that slave-traders were in existence when the New World was opened up...

The idea that the Medieval scholars believed the earth was flat is a lie invented in the 19th century by rationalists eager to find a historical precedent useful for mocking creationists, as documented by the historian St. Jeffrey Burton Russell here and here (I haven't read his book but I've seen him talk).  For more information about the actual Medieval worldview, you can't do better than reading St. Lewis' wonderful book The Discarded Image.  I should have put a gazillion more links in this post, but you all know how to use Wikipedia.

The idea of inevitable moral progress with time is much easier to believe if you only have a superficial notion of history.  I do think that we've made important progress in justice over the past 2 or 3 centuries, but notice that a lot of these involve undoing the moral mistakes of the Early Modern era.  Like all eras, the Medievals had many moral blind spots.  But then again, so do we.

 

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