Tuesday, June 9, 2015

Transcript - Drake equation; Transcendant Man

Class: Informatics, Computing, and the Future
Instructor: Dan Berleant
Transcriber: Brooke Yu
Date: Tuesday, April 02, 2013

Professor:  Okay.  Either one.  You can do either one.  Well, why don't you put it on your blog?  That'll be easier. 

Professor:  Okay, so I'm passing out the next homework.  I guess before I ask you to read it, let me ask you if you have any questions about the homework that's due today. 

Male Student:  So do we need to submit the outline that we're going to do- is that for our purposes or do we need to put that online? like step number 5 or 6.  Or b. 

Professor:  Okay, so at this point you've been doing pieces of your report and I'd like to get you to start putting it all together.  Go through your posts and put it all together.  So you have 500 words on this post, 300 on that.  Put them all on one document.  Your question is....

Male Student:  Do we need to put it on our blog or is that just for us?

Professor:  Put it on your blog so you can always get to it. 

Male Student:  Okay, so here's a curve ball.  What if over the past week our project has changed due to collaboration with other classmates? 

Professor:  Okay, in that case your final report will be what an appendix of the original project so you don't lose it.  That way you'll have a two part project. 

Male Student:  Okay. 

Male Student:  I was writing a creative story, but I don't know how I'd present it besides reading it, but that would be boring. 

Professor:  Well, another thing you could do is normally the story has people talking.  We can pick classmates to each play the part. 

Male Student:  Well, this is just third person.  If I read it, people would probably leave. 

Professor:  Well, the story should be entertaining enough....

Male Student:  Well, I think it'd be interesting if you read it yourself. 

Male Student:  You could do silly voices. 

Professor:  Well, why don't you include the story as an appendix to your final report?  I have no objection.  When people write stories they sometimes just read part of it.  But if you're not comfortable with that, then don't discard what you've done.  Hand it in as an appendix.  So what's your new project? 

Male Student:  We've been discussing doing a form of a skit or a video or something along the lines of a future outbreak- something like that

Professor:  Okay, I'll let you figure that out.  That's fine.  One of the objectives I have is I want to give you the points for the work you've done, so put your past work in there too.  If you did some work, you should get something for it.   So you guys will see me after class.  We're getting towards the end of the semester.  Things are starting to come together and hopefully you've done enough stuff that pulling it all together won't be too scary.  Other questions? 

Alright, I just passed out homework 9.  Take a look at that to see if you have any questions. 

Male Student:  So on homework 9- something the equivalent effort.  That means if we do a skit, that would be like getting together for rehearsal. 

Professor:  Sure.  Something like that.  Or you could have the script. 

Male Student:  Okay, cool. 

Professor:  Okay, any other questions? 

Okay, well, if you look at question 2- well, I printed out copies of the story.  Even if it wasn't for credit. 

So I'm going to hand these out. 

So while these are getting passed out- I was thinking about printing all these on paper.  I know some people don't like that.  Do you prefer to read stuff online or do you like having the paper copy? 

Male Student:  I'd say paper. 

Professor:  Yeah, now you have an option.  I read stuff online, but I find paper a little easier to read.  I thought maybe it was old fashioned to hand out all this paper in class. 

Male Student:  It's just unusual for this college.  It's strange for the EIT department. 

Professor:  I think paper is okay to keep notes and I think it's easier to read.  So let's see.  So last time we started talking about intelligent life on other planets, and we'll finish that up today.  Then we'll go on to the Singularity.  There are some early classic works on the Singularity, like I just handed out. 

There's another we'll look at, and there's a movie I want to show too.  It's called Transcendent Man.  Did anyone see that in theaters? 

So it'll take us a couple times to get through the singularity. 

So let's finish our discussion on intelligent life on other planets.  We looked at an equation.  Do you remember it? 

Male Student:  It was the Drake equation

Professor:  Right.  And, what it tells us if you calculate everything, it gives N, which is the number of advanced civilizations in the milky way we could communicate with.  If it existed before we can't communicate with it, but how many could we communicate with now?  We just have to multiply all these factors. 

Let's go ahead and do those factors. 

So N equals. 

r is [On board.]  

We looked that up, and it turns out we get 10/year. 

We just keep multiplying.  This is the fraction of stars with planets.  It wasn't known when drake made this equation, but we know it's about 2%.   Here, it's 2.7% [On board.]  

So we don't have to keep track of a range.  We'll just estimate as 2%. 

So this value is the fraction of stars with planets.  The suitable planets per star is the next factor. 

So let's say... what is 2% in numerical terms? 


And moving right along to the next factor, which is fractions of suitable planets that do develop life.  We know of one- earth, but we don't know any others, so we vitae guess on this factor

Male Student:  We could say 1 in 8 or 9. 

Professor:  Oh, what did I do? 

Male Student:  If you go to recently closed on the bottom on the right, it should pop open. 

Okay, so faction of suitable planets that do develop life- someone suggested 1/8 or 1/9. 

Professor:  Okay, how about 1/8.5.  We could put in ranges here, but we won't

So for every planet.... out of 10 planets that develop life, what fraction develop intelligent life?  It's this one. 

Anyone want to take a guess?  Of course, it's just a guess. 

Alright, your guess is as good as mine. 

5% is 0.05.  So of those that develop intelligent life, fraction of intelligent civilizations that are detectable.  Maybe they exist, but they don't have radio waves.  So what fraction do we want to guess is detectable?  Anyone want to take a guess at that? 

Male Student:  Assuming they're intelligent, they'll keep advancing, so I'll guess at least 50%. 

Professor:  That's one way to reason through.  But there's no scientific way to do this.  Drake couldn't even come up with guesses.  So these might not be precise results. 

So 50% of civilizations are detectable. 

Length of time they're detectable.  How many years do you think a civilization would be detectable? 

Male Student:  You'd have to take into account how long our civilization has been along. 

Professor:  Well, that's a thought.  We could say we've been detectable for 100 years, but maybe we'll continue to be detectable for the next million, or maybe we'll go up in a mushroom cloud. 

So we have to come up with a number for these equations.  We know it's probably at least 100 years, maybe a million years.  I don't know.  Do you think the human race will exist in a million years? 

Male Student:  No. 

Male Student:  No.  Well, not on earth it seems like we're destroying earth pretty quickly. 

Professor:  100 years? 

Male Student:  I think we'll be here in 100 years. 

Professor:  Should we put in 1000 years?  Here's another thing.  Maybe the civilization exists, but they're not using radio waves.  People watch more and more TV on cable now.  But still, we're using cell phones like crazy, and a number of years ago phones were just land lines which aren't detectable.  So let's say 1000 years just to give us a number.  Is that okay? 

Male Student:  That works. 

Professor:  Alright.  If we want to know how many civilizations are detectable, we just need to run through this equation. 

Alright.  I'm going to say 1/10 here to make the math easier then we get... okay, [On board.] 

[Teacher reading: [On board.]  

We want to multiply a decimal by 1000, so just move the decimal over 3 places.  So we got 0.5. 

That says that there's a 50% chance that there's another civilization in the milky way that we could communicate with and detect. 

Okay, so you know, number of advanced civilizations we could communicate with comes out to 0.5, which is a 50% chance.  This could explain why we haven't found another civilization yet.  Maybe we do have company, maybe we don't. 

So if the average civilization last a million years instead of 1000, then it'll be more likely. 

So what that means is that people who really want to take this equation seriously have to think about how to estimate these numbers.  That's another difficult problem.  You could spend a whole class on these factors to come up with something.  

So there it is.  Drake's equation, but the problem is it's really hard to figure out a reliable answer for it.  We could also use ranges for these to figure out estimates. 

Alright, there are some other problems and issues that come up with this concept of communicating with extra terrestrials. 

Even if they were out there and they were detectable, we might not recognize their signals

We can't communicate with dolphins even though we've found that they can communicate with each other.  That's another critter on the earth- not some extra terrestrial.  At least we'll have to find the planets they're on though.  How do we find useful planets? 

The first thing is to be able to find planets at all.  You know, when I was your age there was no way we could detect planets outside the solar system, but now we can do it.  You know how? 

Male Student:  Giant telescopes. 

Male Student:  Doesn't it have to do with the way the light pulses when a star passes in front of it? 

Professor:  Right.  If you have a star here, and a planet orbiting - if this was the sky- let's turn this 90 degrees and suppose we're seeing it edge on.  Now we have a star and there's a planet going really narrow because it's edge on.  Here's the orbit. 

Every time it passes in front of the star it'll dim the star a little bit.  They can detect that dimming.  If it dims every 10 months or 1 month, then you know there's a planet orbiting with an orbital period of 10 months or 1 month.  The first planets they found were very near the stars and had a week or something. 

So you've got these enormous planets that are super hot- thousands of degree- those are the ones that would dim the light the most and most frequently. 

So they found some really exotic planets unlike anything in our solar system. 

In more recent years they've found planets farther from the sun and they found some planets that are earth like.  There could be liquid water there, and the planet's big enough for gravity to hold an atmosphere, but small enough that it's not just a big gaseous planet. 

Male Student:  I was wondering if they turned the hubble telescope to the moon if they could see dirt particles on the moon. 

You know what I mean? 

Professor:  That's a good question.  The moon doesn't have an atmosphere, so that's a good question.  I know they can see small things. 

Male Student:  If there was an astronaut on the moon, maybe they could zoom out and see them waving. 

Professor:  Well, they can see these planets, but they can't really, really see them. 

Male Student:  Okay, if I'm looking at an astronaut and I see him waving, what's the latency? 

Professor:  Well, it's limited by the speed of light.  It'll get between us and the moon in a couple seconds.  There will be a delay, but not that much of a delay.  If you've ever noticed on the cell phone- there's a delay of a second or so. 

A lot of that is the speed of light.  Your voice has to travel to the tower and then to their phone.  Maybe you can't tell if they're in town, but if they're across the country, there might be a delay.  Electronic signals go about the speed of light. 

Even if they turned the Hubble telescope on these distant planets, they wouldn't see them because they're too tiny. 

They can't see anything on the planets.  That's true for distant bodies in our own solar system like Pluto.  Let's take a look.  I'll show you what they can kind of see. 

Here's Pluto.  So we can see a little bit.  We know it has some dark patches and some light patches. 

Male Student:  But Pluto's not a planet anymore, right?  It will always be a planet to me. 

Professor:  Yeah, they forced it into retirement. 

Male Student:  You know it has only made a 4th of its orbit since we've discovered it. 

Professor:  Yeah, what's it's orbital period?  Like 200 years?  Compared to Jupiter, we can see the weather patterns on Jupiter pretty well. 

Alright, so even modern technology.  I guess we had a spaceship that has passed the orbit of Pluto, but I don't think it got close to Pluto. 

Okay, so they need to find planets, and they've been doing that and they do that by the planet crosses over the face of the star, which means we miss a lot of planets too

It'd also be nice to find oxygen.  Oxygen is a very corrosive, active chemical.  We don't notice that because we breathe it and we need it.  But it's so corrosive and reactive that it wouldn't exist on earth if it wasn't continuously produced by plants. 

No planet will have oxygen unless it is produced by something like plants.  If you can detect oxygen, that's a good indication that there's life on another planet. 

If we detect oxygen, that means there's life.  That's a pretty, you know, good way to tell.  And there's hope that we'll be able to detect the oxygen on distant planets.  Every chemical has its own light frequencies that it tends to emit and absorb, so they can detect gases on distant objects by looking at the spectrum of light reflected from it. 
So maybe we'll be able to detect oxygen on a distant planet.  It could happen some day. 

Alright, so our ultimate objective is it's nice to find enormous planets with orbital periods of 2 weeks, but we really like to find earth like planets that are smaller and cooler with water on them. 

When you were born we didn't know of any extra solar planets, but now many have been discovered.  The first ones were huge and hot, but we're getting better at finding earth like ones.  Here are three. 

Gliese just stands for- there's a catalog of stars nearby with that name.  So here's three planets.  One is Gliese 667.... let's see.  One is this one, and what does that name mean?  Gliese is just the catalog of stars, star number 667, it's a triple star- that means three stars orbiting each other, so that's star C of the triple star 667, and that star has at least three planets, so we'll label those a, b, and c. 

So that's planet c of Star C of group 667. 

Here, I even mention it down here. 

Here's some stats on star C which this planet revolves. 

It's about a third of the sun's mass, close to half the sun's radius, and as the start gets smaller, the brightness really decreases. 

Of course, if a star is only 1% of the sun's brightness but 37% of its mass, it'll last 20 times longer probably than the sun.  Our sun will only last maybe 9 billion years, but Gliese 667C should last 20 times longer than that. 

So this is the... I guess C is the second planet.  I don't know, maybe they skip A.  So it's a big bigger than the earth- 4 times bigger.  It orbits the star every 4 weeks.  A year there is a month here.  If you were standing on this planet- a whole year would be 1 month long.  We don't know how long a day is.  But we know the star would be twice as wide. 

So it'd be like having a giant dim sun in the sky- probably redder than our sun.  So it should be sort of, you know, maybe the sky would be pink.  They think the temperature should allow for liquid water. 

If we only had strong enough telescopes, then maybe we could see if there's oxygen or life there, but who knows.  We can't tell yet. 

Do you think we have pictures of the planet? 

Male Student:  No. 

Professor:  No.  Because it's too far away.  We can't even get a decent picture of Pluto.  But that hasn't stopped artists. 

It's 22.1 lightyears away.  It's pretty far away, but pretty close on a galactic scale. 

So we don't have any pictures, but let's see what artists have thought. 

Let me type in the name of the planet. 

Here are some artists' renditions.  They're dim and reddish.  They postulate about whether there's water.  Here's another artist's rendition. 

This is just purely guesswork.  We have no idea if it looks like that.  It might look completely different. 

Here's another.  If it had water on it, maybe it'd look like that.  Who knows. 

Here's another one.  This is.... this is Gliese Catalag 581.  It's a small red star. 
I don't know why they think it might not exist. 

Maybe they're not sure about the planet.  They're sure about the star, which would be planet g- about 4 times earth's mass.  It always has the same side facing the star.  So where you are on the planet it's either always day or always night. 

Why is that a problem?  Or is it a problem? 

Yeah, it'll be too hot on one side, too cold on the other.  What if night was forever?  It'd get really cold.   So that's a pretty serious problem.  The only way around is if you have a thick atmosphere that can hold heat, then you have winds that distribute heat.  Venus is like that.  Venus' day and night are slow- day is approximately 2 months long.  So the sun would rise, then it would set in a month.  But its atmosphere is so thick and it holds so much heat that it's the same temperature everywhere both night and day. 

Here's another planet-Glies 370.  The bigger planets are easier to detect.  As we get better at it, maybe we'll spot some smaller ones. 

Male Student:  Could we live in a higher gravity?  Wouldn't that stress your heart? 

Professor:  Suppose you weigh 150 pounds.  How much would you weigh on this planet? 

Male Student:  210. 

Professor:  Yeah.  So you weight 150 pounds now.  You'd weight 210 pounds on that planet.  It would stress the heart a little bit, but I think you could manage it.  But you'd feel it.   It wouldn't be like living on mars. 

So I guess 1.4 times is probably okay.  Getting up to 2 times might be a bit of a problem.  If you weighed 150 pounds here you'd weigh 300 pounds there

So this planet may have liquid.  We don't know. 

Let's see if we can find an artist's impression of this planet. 

I guess you don't want to take these too seriously because we don't know what it looks like.  But here's one concept of what it might look like.  Here's someone guessing what it looks like. 

Male Student:  There's an artist who does something like that with a red atmosphere. 

Professor:  We found planets that are so hot that the surface- the rock surface is liquified.  So it would be glowing hot ball of lava. 

Alright.  So let's see where we are here.  Okay.  Any other questions or comments about other planets that might be habitable? 

They say water used to flow on mars

Male Student:  Yeah, because it has river beds. 

Male Student:  Where did it go? 

Male Student:  Its atmosphere is gone so it probably evaporated. 

Professor:  Yeah.  The gravity there isn't as strong either.  Or maybe the water reacted with the rocks and got sucked into the rocks.  They found ice on mars too.  

I was reading that on earth, they think that the water will be chemically combined with the rocks and the earth will be extremely dry after that.  The process is slowing down as the earth gets older, so eventually the water will just combine with the rocks. 

It's interesting that the ice is pretty common.  They found ice on the moon and ice on mercury.  So where could there be ice on mercury if it's close to the sun? 

Male Student:  On the poles. 

Professor:  Yeah, maybe on the poles.  On the poles there are craters that are in perpetual shadow so it's cold there.  And at the bottoms of those craters they've found ice.  I think mercury would be a good colonization option because you could build a colony in those craters to stay away from the sun, but stick a solar panel up there to catch energy.  

So that's will we find intelligent life. 

I'd like to switch gears and go on to the next topic which is singularity.  It's a very different topic. 

But I guess we will start another topic. 

The first thing I'll do is- let me pitch this story.  It's called "the Last question." 

It's by Isaac Asimov.  Does anyone know of any works that he wrote? 

Male Student:  IRobot. 

Professor:  Right.  They made those into a movie.  The movie is nothing like the book. 

Male Student:  There's a lot of laws about robotics.  How many have heard about the three laws of robotics? 

Male Student:  Not other than the movie. 

Male Student:  A robot can't harm a human being... something about the robot has the right to protect itself

Male Student:  And it has to do what its owner says. 

Male Student:  It can protect itself unless it violates rule 1.  And the last is do everything your owner says unless it violates rule 1 or 2. 

Professor:  Okay.  So these are right? 

Male Student:  Protect yourself unless it's to hurt a human.  Then 3, follow orders unless it harms you or it harms a human. 

Professor:  So if you order it to attack a human it won't do it. 

Male Student:  2 and 3 are supposed to be switched. 

[Student reading: on Internet. 

Professor:  This is interesting because as we get robots get progressively more powerful, these might start to make sense. 

So the story I handed out in pitching it- it's about an intelligent computer.  That's the only hint I'll give you.  I think you'll find it interesting to read in your spare time. 

So that's the last question.  The other famous work I want to mention is the technological singularity.  Vernor Vinge was a professor and he's a science fiction writer.  He wrote this essay a while ago where he proposes that computers will get more and more intelligent until we reach the technological singularity. 

For the homework, you can read this or you can read the paper I handed out.  Or both

So what is the singularity. 

I want to tell you about- I want to go through these notes, but I want to watch this movie.  Let me give you a hint before we start the movie.  It's by Ray Kurzweil.  He's linked with this singularitarian idea that there will be a singularity and it will revolutionize our world.  He wrote a book called the singularity is near. 

He's also an inventor.  He invented the scanner and some other things.  Since singularity is so closely linked to him, I'd like to spend the final 20 minutes of class watching a part of this movie.  Then we'll finish it next time and finish our notes.  So let me fire this thing up. 

Professor:  Maybe the sound isn't working. 

Okay.  I'm just going to restart this thing. 

That might have something to do with it. 

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