Monday, July 30, 2012

Trailer: Cloud Atlas

I gave Cloud Atlas, the novel, a very positive review, but I wasn't sure if the upcoming movie would be good.  This trailer assures me it will be amazing!  I am very excited for this film now.  It will be released on October 26 (in the US).

Sunday, July 29, 2012

Fair Dice

There are three six-sided dice, with the numbers 1 to 18 on their faces.  If you roll any two of the dice against each other, each one is equally likely to "win" by rolling the higher number.  If you roll all three dice, they are equally likely to win.  No ties are possible.

One die has the numbers:

1, 5, 10, 11, 13, 17

Can you figure out the numbers on the other two dice?

This puzzle was inspired by a much harder puzzle submitted by Eric Harshbarger to MathPuzzle in April 2012, where there were four twelve-sided dice.

Thursday, July 26, 2012

What I learned about asexuals from gay men

This was cross-posted on The Asexual Agenda.

I spend a lot of time in both asexual and gay communities.  Specifically, I've participated in queer college student groups and have lots of gay male friends in their 20s/30s on the U.S. west coast.  Based on these experiences, as limited as they are, I wish to share a few striking differences.  This is not an attempt to critique either asexual or gay communities but an attempt to understand ourselves.

1. One asexual community, many gay communities

One time someone asked me, "Where is the main bisexual website?"  They expected there would be a bisexual equivalent of AVEN!  Nope.

In the past, people have complained when I've referred to the asexual community in the singular rather than the plural.  I think whether you call it "the community" or "communities" is arbitrary.  But there is definitely a sense in which the asexual community is more unified than the gay male community.  With gay men, they have their circles of friends, and they might participate in local community events.  Some participate in national activist organizations and dating websites, but these don't really provide a unified community.

But since asexual communities are mostly based on a handful of websites, we have a relatively unified community that even crosses national boundaries.  The biggest divisions are between AVEN, tumblr, and the non-English sites, but our differences probably aren't nearly as big as some of the differences within the gay male community.

2. Definition precision

Most of us can recite AVEN's definition of asexual word for word.  And we think every single word is important.  It's a consequence of having a single major website with a single definition featured prominently on its front page for over a decade.  It's also a consequence of many of us having to explain it in great detail to others.

My friends do not have a precisely worded definition for "gay", and this does not seem particularly unusual to them.  Gay men are attracted to other guys.  Or they like other guys.  Or they think guys are hot.  Or they like dick.  Or whatever.  It's not that complicated, or at least, they won't talk about the complications all the time.

3. The behavior-orientation distinction

The behavior-orientation distinction is more important to the asexual community.  Not that it isn't important in the gay community.  But people will gossip and joke about apparent behavior-orientation discrepancies.  If a bisexual man only has sex with or dates one gender, people talk about it, even if they don't outright question it.  If a gay man used to enjoy dating women before he was out, it's often interpreted as being slightly bisexual or fluid.

Whereas, most educated asexuals will ardently repeat the fact that asexuals can enjoy sex.  We talk about aromantics who date, romantics who don't.  I get culture shock when my gay friends don't have the same attitude.

For those who participate in gay communities, do you see the same differences, or does your experience contradict mine?  For those who don't participate in gay communities, do these differences surprise you?

Monday, July 23, 2012

Why I'm agnostic on cosmology

In my previous post, I said that there were many solutions to the entropy problem, but I did not want to pick one.  I think I should better explain my motivations for this.  Why am I so agnostic about cosmology?

Part of it is that I really just don't know.  I'm a grad student in condensed matter.  I know a little about quantum field theory, general relativity, and cosmology.  But like the saying goes, the more you know, the more you know you don't know.  I know that there is a lot of cosmology I don't understand.  I know that cosmology is a complicated field that you can't truly understand just by reading Brian Greene.

I tend to think that if I don't have an opinion on cutting-edge questions of physics, nor should lay people.  I mean, if I don't know enough to speak, and lay people know less than I do, then clearly lay people shouldn't be speaking either.  Just because they read some Brian Greene doesn't mean they understand anything!  That's how physics cranks are born, you know.  They read some popular physics and think they understand.

But I am being unfair to lay people.  They can enthuse about physics all they want.  Physics is cool!

Of course, when lay people speak about physics, they don't get taken seriously.  When I speak about physics, I get taken more seriously.  If I were to even speculate on whether inflationary theory is correct, then I would appear to be giving my expert opinion.  But I don't have the necessary expertise, and I want to make that clear.  My expertise allows me to speak on certain things: the foundational theories of physics, the consensus of physicists, understanding what other physicists say.  But I do not have the expertise to go beyond the consensus.  For the most part, I cannot even go beyond the consensus in my own field, much less cosmology.

But there's another side to this too.  I don't like the idea of atheists being ideologically committed to one particular cosmological scenario.  The situation bears too much resemblance to Creationists, who are committed to a relatively young universe.  It bears too much resemblance to liberal Christians like William Lane Craig, who hold that the universe must have had a beginning.  Of course, mere resemblance to something bad does not mean it is bad.  But it makes me uncomfortable to see atheists advancing one particular cosmological theory in a philosophical argument.  What if that theory is wrong, huh?

Here's a specific example.  I most often see atheists advancing one particular solution to the entropy problem.  The solution is that when the universe was very small, its maximum entropy was also very small, and that's why we start with a highly ordered state.  As the universe expanded, the ceiling on the entropy rose, allowing the entropy to increase as described by the Second Law.  The purpose is to demonstrate that yes, there are possible explanations for the Second Law besides God.

Though I agree that there are many alternative explanations besides God, I am not convinced that this particular explanation is necessarily true or complete.  If a small universe has less maximum entropy, that seems to imply that if the universe undergoes a big crunch, then the entropy will decrease.  Does that mean the arrow of time will be reversed?  People have seriously proposed this, but Wikipedia calls it "a highly controversial view".  There's also the question of why the universe ever compact to begin with.  If a small universe has low entropy, this means that the there are very few possible ways for the universe to be small.  So why was the universe small and compact, out of all the ways it could have been? Some people would argue that at the universe has to be small and compact at its beginning (due to General Relativity), but this basically concedes that the Second Law implies that the universe has a finite age.   I don't think we should concede that.

Keep in mind that I am not an expert, and I could be completely wrong about these objections.  I don't wish to appear an expert where I'm not (see above).  However, I believe that experts in the relevant fields have raised similar objections.

And that is why I take an agnostic approach to cosmology in the cosmological argument.  I don't know enough about it, though I appear to be an expert.  I don't want us to be ideologically committed to a theory which may or may not be correct.  I don't believe this hinders our refutation of the cosmological argument.

Sunday, July 22, 2012

The Asexual Agenda

I started a group blog, The Asexual Agenda.  It's an asexual blog which provides news and views, going beyond the 101 level.  It's also meant to stimulate asexual blogging by providing a portal to other blogs, and a space for discussion.

And yes, this will likely interfere with this blog and ultimately decrease my blogging rate.  To what degree, we'll see.  I will cross-post some things, but not everything.

In case you didn't know, this is the asexual agenda:
1. Blog
2. ???
3. World domination

Just like in Ender's Game.

Folding in thirds solution

See the original puzzle

This is one of those puzzles where the solution is very simple and easy to find, but only if you're looking at it the right way.

So here's what you do:
1. Fold the rectangle in half along a vertical line.  Unfold it.
2. Fold the rectangle along a diagonal.  Unfold it.
3. There's one last fold, shown in this diagram.  (The diagram shows a square, but this works for a rectangle of any dimensions.)  Unfold it again.
4. The diagram shows the intersection of two creases (made by steps 2 and 3).  Fold the bottom edge of the paper up to this intersection.  This is the one third fold.

Wednesday, July 18, 2012

Entropy: The unsolved problem

This post is part of "A few things wrong about the cosmological argument", a series using the cosmological argument as an excuse to talk about other stuff.  

On a side note, I recently discovered that Chris Hallquist has a book review of William Lane Craig's Reasonable Faith, and is talking about his cosmological argument right now.  I recommend his William Lane Craig tag.

I previously talked about William Lane Craig (WLC) and his scientific argument that the universe must have had a beginning.  I think this is, in principle, a good argument, but WLC exaggerates his case by misrepresenting Big Bang cosmology.  Today I will discuss another scientific argument involving entropy.

The entropy argument

I've explained the definition of entropy elsewhere, but the short version is that entropy is disorder.  The idea is that physics gets really complicated when we have billions of billions of objects bouncing around, and we can't really keep track of it all.  So we describe the system with aggregate properties, even though we're really piling together many microscopic states by ignoring the details.  The entropy tells you the number of microscopic states we've piled together.

A disordered desk has higher entropy than an ordered desk because there are lots of different ways to arrange things on your desk such that it looks disordered, but only a few ways to arrange them such that it looks ordered.

But note that the amount of entropy involved in arranging a desk is actually very trivial.  I have a moderately messy desk with two dozen different objects in it, but this doesn't hold a candle to the billions of billions of molecules in a single mote of dust on my keyboard.  Likewise, arranging atoms into life-forms actually trivial in comparison to the amount of ordering involved in sunlight.

The Second Law of thermodynamics states that entropy increases over time in a closed system. The idea is that all those complicated processes involving billions of billions of objects are more or less random.  Therefore, each accessible microscopic state is equally likely.  High entropy states contain a far greater number of possible microscopic states, thus higher entropy states are more likely.  So if we have a system in an ordered state, it is likely that its entropy will increase.

Of course, for this argument to make sense, we have to have an ordered state to begin with.  Otherwise, the system would be in a state of maximum entropy, and continue to be in this state indefinitely.  And then that ordered state has to come from an even more ordered state, which had to come from an even more more ordered state.  This chain can't continue forever, since it's thought that entropy has a lower bound.  (Think of the lower entropy bound as a system which is so orderly, that it corresponds to exactly one microscopic state.)  And so we argue that the universe must have had a beginning with very low entropy.

WLC stops there, but one could go on to argue, by analogy, that the universe is like my desk.  Just as the desk required a sentient being to rearrange it so it has some semblance of order, so the universe must require some sentient being to carefully place it in an ordered state at the beginning.

This argument fails because I don't really reduce entropy by rearranging my desk.  Rather, I am simply reducing the entropy of my desk arrangement at the cost of greatly increasing other entropy.  Furthermore, the vast majority of processes which reduce entropy (at the cost of increasing entropy elsewhere) do not involve any sentience.  Take, for example, the fact that the poles are colder than the equator.  Such a temperature difference implies a far greater amount of order than could possibly exist on my desk.  But this order was created by completely mechanical processes like sunlight.  So even if the universe is analogous to smaller ordered systems within the universe (which is itself highly questionable), then this does not suggest that sentience is involved.

An unsolved problem in physics

The Second Law of thermodynamics really does present a problem in physics, and WLC deserves credit for getting that much right.  Allow me to re-frame the problem as a physicist sees it.  Imagine that we use our knowledge of physics to predict what happened further and further into the past.  On the microscopic level, this is no different from predicting the future.  Just as there is exactly one* path it can follow into the future, there is exactly one path it can follow into the past.  But because we can't keep track of the motion of every particle, we use statistics and thermodynamics, including the Second Law.

*I'm temporarily using the MW interpretation of quantum mechanics, which is deterministic forwards and backwards in time.

Assuming the Second Law holds true forever into the past, it seems that at some point in the past there is nowhere for our prediction to go.  We'll find the universe in a state which cannot have come from any lower entropy state.  Mind you, this does not mean that the universe cannot have come from anywhere at all.  Remember, on a microscopic level, there exists exactly one path the universe can follow into the past.  It's just that this path can no longer obey the Second Law.

It's possible that the Second Law of thermodynamics does not hold forever into the past, in which case, our universe is presently in a statistical fluctuation to a low entropy state.  However, there's a powerful argument to suggest this is not the case: if humans are only formed by statistical fluctuations, then the vast majority of humans would find themselves in much smaller statistical fluctuations than the one we see presently.  (I've discussed this "Boltzmann Brain" argument before, so I won't dwell on it further.)

So yes, it is a problem.  But a "problem in physics" does not mean "We can't think of any solution".  In fact, it usually means that there are many solutions, and we can't figure out which one is right, if any.  Unfortunately, there's a major obstacle to figuring out the correct answer here: quantum gravity.  As explained before, we don't have the theory required to predict past a certain point in the past.

I do not know what solutions people have advanced and argued for this problem.  There are probably many solutions involving loopholes in the Boltzmann Brain argument, loopholes in the lower bound of entropy, quantum mechanics, or a beginning to the universe.  I do not wish to opine on this matter, since as a physicist my answer would be taken seriously even though cosmology is not my field.

In my field, superconductivity, one of the great unsolved problems is the mechanism for high temperature superconductivity.  But in fact countless mechanisms have been and are being proposed.  So if someone suggests that our inability to find a solution means we should look to the supernatural, they've fundamentally misunderstood the problem.  We don't just need solutions, we need data to determine which, if any, of our existing solutions are correct.

(ETA: also see "Why I'm agnostic on cosmology")

"A few things wrong about the cosmological argument"
1. Actual and potential infinities
2. Actual infinities in physics
3. What is real?
4. The "absurdity" of Hilbert's Hotel
5. Interlude: God is infinite
6. Forming Infinity, one by one
7. Uncertain beginnings
8. Entropy: The unsolved problem
9. Kalam as an inductive argument
10. Getting from First Cause to God 

Monday, July 16, 2012

Games with your future self

Sometimes my boyfriend tells me that he's going to go to the gym at a specific time in the future.  This is a way of forcing his future self to go to the gym, because otherwise he's breaking a promise to his boyfriend!

We could leave it at that, but I am a fan of over-analysis.  In what sense is it rational to limit your own decisions?  How can it be beneficial to punish your future self?  I will offer three levels of explanation.

One level deep

We behave irrationally.  But that does not mean our behavior is unpredictable.  My boyfriend can predict that if he makes the promise to me, he will go to the gym.  If he does not make any promise, he will not go to the gym.  Knowing this, it is rational to choose to make a promise to me.  His overall pattern of behavior is irrational, but his response to his own pattern of behavior is rational.

Two levels deep

Our present selves and future selves have different preferences.  Thus, we can imagine a two player game, roughly represented by this payoff grid.

In this grid, PBF represents the present boyfriend, and FBF represents the future boyfriend.  First PBF makes a decision, then FBF makes a decision, and the payoffs are represented by the numbers in the corresponding box.  Each player prefers a higher number of their own color, and doesn't particularly care about the other player's payoff.

I admit that I never bothered to take a class on game theory, but I think this is pretty easy to analyze.  As I said in the previous level, it is rational for PBF to make a promise.  But unlike the previous level, we can see that FBF's choices are also rational, it's just that they follow a different preference ordering.

Three levels deep

The previous level begs the question, why does a single person have different preferences at different times?  I'm not sure I can show this to be rational, but I can put it in a larger framework.  It's called discounting.

The choice of going to the gym basically has two consequences.  The first consequence is that you have to work hard at the gym.  The second consequence is that you become more fit.  Each of these consequences is associated with a particular time.  The hard work at the gym is associated with the near future, and the fitness is associated with the far future.  Because the fitness is in the far future, its perceived value is diminished by the discounting factor.  The discounting factor is a decreasing function of time, so that far future consequences are more diminished in value than near future consequences.  This function is called the discounting function.

This is a diagram showing the discounting functions of the present boyfriend (PBF, green) and the future boyfriend (FBF, blue).  As he gets closer to the time of going to the gym, its perceive value increases in magnitude, as does the perceived value of the fitness.  However, working at the gym has a negative value (at least in his case), so its perceived value is actually becoming more negative.

Within this framework, it is possible that the rate at which the gym value grows more negative is greater than the rate at which the fitness value grows more positive.  It's possible that my boyfriend's preferences could flip.

But note that this requires a certain shape of discount function.  Economists usually talk about two particular discounting functions.  The exponential discounting function just decreases exponentially.  The hyperbolic discounting function decreases like 1/(t+C), where t is the time and C is a constant.  With an exponential discounting function, preferences will never flip (except where some consequences occur in the past).  With a hyperbolic discounting function, preferences may flip.

Basically, with hyperbolic discounting, we strongly value consequences near the present, but all the consequences in the distant future look about the same, even if those consequences are actually relatively far apart from each other.  Thus, from PBF's point of view, the gym workout and resulting fitness are both discounted by about the same amount.  But from FBF's point of view, the fitness is discounted much more than the gym workout.

From a certain point of view, discounting makes rational sense.  Future consequences may simply not happen the way we predict.  An intervening event could prevent their occurrence, or further information could put our predictions into question.  If the intervening event mostly occurs when the future consequences are in the near future, then hyperbolic discounting makes more sense than exponential discounting.

On the other hand, I'm pretty sure this is not what is going through my boyfriend's mind when he flips preferences.  Discounting is sort of an inherent component of our thinking.  Maybe it's a heuristic rule we learned when we were young, or it was evolutionarily adaptive (or neither, or both).  Whatever the reason, it appears to describe our preferences.

Thursday, July 12, 2012

One man's modus ponens, another man's argument from morality

Update: I fixed some serious formatting issues with this post.

There's an argument that goes, if God didn't exist, then there would be no reason for us not to do action X.  But action X is obviously terrible, so God's non-existence would have terrible consequences.

This is a fairly weak argument, since it's an argument from ignorance.*  Just because you can't think of a reason not to do action X, doesn't mean there is none.  What's worse, the argument undermines itself.  On the one hand, X is supposed to be obviously wrong; on the other, we supposedly have no reason to avoid X without God.

*It's also an argument from consequences, but let's focus on one fallacy at a time.

At this point, a proper response requires splitting into three different cases:

1. Action X is obviously wrong whether or not God exists.

Examples: murder, rape

This is disingenuous.  If it's so obvious that X is wrong, then this contradicts the statement that there is no reason to believe X is wrong.  Obviousness is a reason for belief.

2. Action X is obviously wrong if God exists, but not wrong if God does not.

Examples: same-sex sex, evolutionary science (depending on the religion)

But if X is not wrong, then why would it be bad if people do X?  It seems that the terrible consequences of God's non-existence aren't so terrible after all.

3. Action X is obviously wrong if God exists, but not so clearly if God does not.

Examples: euthanasia, late-term abortion (also depending on the religion)

If an issue is truly uncertain, then it is appropriate to be uncertain about it.  Why should we afraid of lacking hard answers if no hard answers appear?  Isn't it worse to think we know the answer when in fact we don't?

Note that some people will claim that stuff like murder is uncertain without God, but we should take these claims with a grain of salt.  If they truly thought it was uncertain, they wouldn't think it was bad for people to feel uncertainly about it.

In conclusion, the basic argument from morality is fallacious at best and disingenuous at worst. Other kinds of arguments from morality are outside the scope of this post.

An explanation of the title: There's an expression in philosophy that goes, "One man's modus ponens is another man's modus tollens", describing a common impasse in arguments.  Both parties agree that A implies B, but one person thinks A is obvious, and therefore B is true (by modus ponens), while the other person thinks B is absurd, and therefore A is false (by modus tollens).  This describes the situation with the argument from morality, but if you can't see the connection, don't worry about it.

Monday, July 9, 2012

Freethought and other non-literal words

Freethought Blogs kicked out two bloggers who were misbehaving.  Some people pithily said that it goes against freethought to fire people for thinking freely.  (See comments here for examples.)  Plenty of people have already piled on them for making such a stupid argument, but I wanted to put this in context.

"Freethought" is not the same as "free thought".  Freethought is a collection of ideas, a movement of people.  There's actually some substance to freethought beyond its name.

This is likewise true of words like "conservative" and "progressive".  In a political context, conservative doesn't actually mean cautious, slow-moving.  Progressive doesn't actually mean moving towards the future.  They describe a set of political stances, some of which have nothing to do with change vs tradition.  I'm sure that conservatives have at times supported forward-looking policies, and liberals supported the continual of existing policies.

It is a shallow argument indeed to attack conservatism on the basis of its caution, or to defend conservatism on the same basis.  It is totally missing the point to attack "new atheism" for claiming to be new when it's not.  It is a lazy person's argument to say that the skeptical movement is right or wrong because doubt is right or wrong.  It represents a fundamental misunderstanding to act as if homophobia really means a fear of gays and lesbians.

Long story short, if all you can talk about is the name, I'm going to assume that you are incapable of making a substantive argument, and are instead substituting your impressions of words.

Monday, July 2, 2012

Rethinking asexuality as a disorder

This post was inspired by an essay by Natalie Reed explaining why she thinks Gender Identity Disorder is a disorder, and the subsequent comments by Crip Dyke.

Asexuality shows some superficial similarity with Hypoactive Sexual Desire Disorder (HSDD) in the DSM-IV.  It's a similar situation to when homosexuality was classified as a mental disorder in the 70s.  Many asexuals argue that HSDD should be more narrow so as to definitively exclude asexuals.  Others argue that the validity of HSDD itself should be questioned.

I largely agree with these arguments, but I want to discuss one line of argument which is wrong.

"Categorizing asexuality as a disorder means asexuals are dysfunctional and broken, but we're not."

The basic problem presented by HSDD is the following equation: Asexuality = pathologization = stigmatization.  The above argument seeks to break the connection between asexuality and pathology, but takes for granted the connection between pathology and stigma.  This does a disservice to all other people with stigmatized mental disorders and medical conditions.  People with AIDS don't have the privilege of being able to excuse themselves from the medical category just so they can avoid the stigma.  Nor do people with bipolar disorder or OCD.

As a practical matter, breaking the connection between asexuality and pathology may reduce stigmatization. If we truly believe that asexuality is not a pathology, then this is a reason to make our case forcefully.  But the stigmatization is not in itself a reason to believe that asexuality is not a pathology.

Mental disorders are not really meant to stigmatize.

Roughly speaking, the purpose of the mental disorder category is to say, "The best response to these things is through the caregiver/patient paradigm, and possibly through public accommodations."  For example, if a person has seizures, this can be treated with drugs, and if they can't drive we can provide public accommodations such as mass transit.

There is some disagreement over what things are best treated with the caregiver/patient paradigm, but one guideline is that it should cause an impairment in an essential function, or marked distress.  But note that this is not the same as saying people are "broken" or "dysfunctional", since these terms are tools of stigmatization.

I do not think asexuality is best treated through caregiver/patient models.  Asexuality itself is not a problem to be solved.  Asexuality may interact with society and culture to cause problems, but the best response is an education campaign and new community structures.  That's the real reason why asexuality is not a disorder.*  That's the real reason homosexuality is not a disorder either.

*Mind you, there are additional more subtle reasons beyond the scope of this post.

Politics should follow facts.

We should not start with "Asexuality needs to be destigmatized" and immediately go to "Asexuality is not a disorder".  Rather, we should consider the question, "Is asexuality a disorder?" and then in light of its answer choose the best political strategy.  If the answer were "Yes," then we should campaign for destigmatization of disorders.  But the actual answer is "No," so we should campaign for the depathologization of asexuality, while keeping in mind that people with disorders should not be stigmatized either.