StarTalk Radio - Pool Table Physics with Dr. Dave Alciatore

Episode Date: October 15, 2021

What was Coriolis, of the Coriolis Effect, doing at the pool table? On this episode, Neil deGrasse Tyson and co-hosts Gary O’Reilly and Chuck Nice explore the science behind billiards and pool trick shots with billiard physicist Dr. Dave Alciatore.NOTE: StarTalk+ Patrons can watch or listen to this entire episode commercial-free here: https://www.startalkradio.net/show/pool-table-physics-with-dr-dave-alciatore/Thanks to our Patrons Dylan Elliot, Cody Swayze, Panda Man, Niklas Ekberg, Isaac Lambert, Fortune's Flavor, and Joshua Grose for supporting us this week.Photo Credit: Paul Goyette, CC BY-SA 2.0, via Wikimedia Commons Subscribe to SiriusXM Podcasts+ on Apple Podcasts to listen to new episodes ad-free and a whole week early.

Welcome to StarTalk, your place in the universe where science and pop culture collide. StarTalk begins right now. This is StarTalk Sports Edition, and you knew we had to get here eventually. On this episode, we're doing the physics of billiards. Yeah, I said it of billiards. Yeah, I said it. Billiards. The pool, I guess, is also pool. Is that right? That's right.

Yeah, the physics of that. And you know there's physics going on on that pool table. And so we're long overdue for handling this. And I got with me my trusty co-host, Chuck Nice. Chuck. Hey, that's right. One of my favorite subjects, pool. I just, I could have bought another house

with all the money I've lost at a pool. Okay, thank you. It comes out for the first time on Star Talk. There you go, there you go. Chuck's debts in life. And of course, Gary O'Reilly. Gary, former soccer pro. Yes, I know.

Over in the UK. Oh yeah. And Gary, I'm always impressed just with your genuine interest in all things that are not soccer. Yes. So I'm delighted we have you as my co-host here.

So we got this in three segments. One we're going to talk about, we titled Coriolis Impact. Coriolis. More about Coriolis coming up. And then we're going to talk about trick shots. How could you not? Okay.

And another one about the angles. It's all about the angles on the billiard table. The only time geometry is super cool. So when you're in school and you say, I never have to know this again. Yes, you will if you want to become a pool shark. That's right. There you go.

There you go. That's how that works. So before we introduce our pool expert, Gary, give me some background on this sport and this activity. Let's do a brief history, and I really mean brief. So back in the 1400s, the British and the French. Damn. Okay. Wow.

Jesus. And I'm not talking 2 o'clock in the afternoon, right? It's like, hey, Chuck, can you give us your bio? I was born the son of a sharecropper. The son of a son of a sharecropper. I thought all of Billiards began with the movie The Color of Money. Yeah. All right.

Or Minnesota Facts. Okay. So here we go. Okay, so go on. We're way back. So it starts with the British and the French aristocrats who in the 1400s took lawn croquet indoors because during the winter months it was too cold and too wet.

However, the color of the top is green to match the grass that Brocade was played on. Whoa. Right now, the term pool is for pocket billiards that came from America. Where tables were introduced into horse track betting rooms, the betting there was often done in betting pools. So in the mid to late 1800s to provide them with something to do between races. Now, here we go.

Fun fact. Now we're in the 1800s. Wait, wait, wait. Because betting on races is not enough something to do between races. Now here we go. Fun fact, now we're in the 18... Wait, wait, wait, because betting on races is not enough ways to lose your money. You got to add some between the races. Yeah. Okay, that's crazy. So now we're in the 1800s. 1835, to be specific, Coriolis wrote a book on the physics of pool, which... I know Coriolis. I know you do. Me and Coriolis go way back. Don't you badmouth this man. I think he's got an effect that you like.

Yeah. Let me see. It's called the Coriolis effect. Wow, look at that. There you go. More on that. More on that. But go on, okay?

The book was published in French, but it wasn't translated into English until 2005. Wow. There's your fun fact. So we are now looking at one of the classic physicists, mathematicians, with an avid interest, such an interest in the sport of billions, and Paul, that he went away and wrote a book. Amazing.

Okay, so that kind of gives it a little more respect than what it occasionally gets today. Because when we think of pool halls, we think of shady characters. Yes. You know, and smoke in the air, and somebody about to lose their money, somebody about to get beat up in the back alley. And it hides, cloaks the fact that to be good at this sport,

you've got to know some science, you've got to know some physics, and maybe even a little bit of engineering. And since none of the three of us have this expertise, we combed the landscape, and we found the spirit of Minnesota fat. We found Minnesota slim. Yeah. We found Dr. David Alciator. So you're a retired professor emeritus.

Yes, recently. Recently, yeah, because you don't look old enough to be emeritus. At Colorado State University, you got your PhD in mechanical engineering at UT Austin. That's right. And, okay, here it comes. Ready? Dean and co-founder of, are you seated? Billiards University.

Wow. There you go. Wow. Okay. I'm going to tell you something right now, Dave. Sounds a little like Trump University to me. No, just a little. Just a little.

I'm just saying. I'm just saying. No, he didn't mean nothing wrong by it. He's just saying. We have a line of fine steaks we offer as well. What happened when you were a kid and you said, Mom and Daddy, I'm going to start at Billiards University? I don't know how that would have played out back then,

but we'll get into that in a minute. So you've got books on topics as varied as mechatronics. I love that. Mechatronics, Neil. Mechatronics. Get with the program, man. Get with the program. Excuse me.

Mechatronics. What's that about? That sounds like robots that will take over the world. It's a more traditional name is electromechanical systems, which is basically a merge of mechanical and electrical engineering with some computer science thrown in. Right on. Okay, and another book, How to Aim Pool Shots.

I love that. And you've got your own YouTube channel and Facebook page dedicated to pooling billions. This is wonderful to have you on the show. I'm happy to be here. Thanks, Neil. Broadening our sense and understanding of all the cool sports that engage people. So we have like a million questions for you. So any of us who've heard of Coriolis before, whether or not we knew it was an actual person, we heard of the Coriolis force. Tell me about Coriolis and billiards. Yeah, so Coriolis, you know, he wrote this brilliant book in 1835. I didn't see it until 2005 when the English version came out, and that was a year after I

wrote my book. And I had done a ton of work, and when I saw Coriolis's volume of excellent work, I was just crushed, And my heart stopped. Oh, you mean he scooped you? Yeah, yeah, by a couple hundred years. Wow. Now, wait, did you reach the same conclusions, though, without knowing his work? Well, other people, you know, I'm not the only one that's done billiard physics. Other people have done stuff, and many people have come close to duplicating much of Coriolis's work. Before we take a break, because I want to get to what you described,

could you let me know if in this first book that you wrote, Mechatronics, could you devise a mechanical system that could play a perfect billiard game without anyone's intervention? In the same way we can make machines that solve Rubik's Cubes and machines that drive cars, can you do one where it's going to sink the same way we can make machines that solve Rubik's Cubes and machines that drive cars, can you do one where it's going to sink the ball every single time? Yes, people have done this. Now, they're not good enough yet. They're far from a good player. But there are many robots that have been built that can use vision systems, a camera,

to see where the balls are, position itself. It would know exactly where the ball is, right? Exactly, yeah. If you've got a high-res camera. Yes, exactly. So they can see better than we can see, but they can't stroke as well as we can. And they can't plan as well as we do either. Right. But you might think, the planning piece, I think, can be there soon.

But the work that's been done already in that regard, the planning is not quite there. The shot making is not quite there. So just to be clear, when you say the planning, it means when I hit the ball, where the balls end up after my successful shot will matter for my next shot. Bingo. Because that's what the next shot is. That's what the whole game is. The leave, man. It's all about positioning. You got to play the position game. You got it, Chuck. You got to make that shot, but you got to make the cue ball go to where a place where the next shot's going to be easy. Right. Chuck, why are you this fluent in this? Like I told you, man.

Could have bought a house with all the money I lost. It's a very expensive education. Very expensive education. All right, when we come back, we're going to take a quick break. But when we come back, we will get into the details of the famous, or is it infamous, Coriolis shot on StarTalk Sports Edition. We're back. StarTalk Sports Edition.

All about billions. The physics of billions. Of course, that's how we roll on StarTalk. I see what you did there. That's how we roll on StarTalk. I see what you did there. That's how we roll. Okay. All right. We've got our guest, Dr. David Alciatore. Alciatore.

Yeah, I want to pronounce it in its Italian way, and my tongue is not letting me. Alciatore. Yeah, I want to pronounce it in its Italian way, and my tongue is not letting me. Alti e torri. So, Dave, this is great that you've devoted your career to this, even with active social media presence promoting it. So, let me hand over to Gary and Chuck, because I know they've got a million questions for you. We have, Neil, because it's so interesting. The Coriolis sort of situation,

particularly with parabolic cue ball parts, it sounds as if I should not understand it, but I think I do, but I need a really good explanation from Dr. Dave. Okay, here it comes. You ready? Yeah. All right. Let's do it.

Okay, so Coriolis, you know, if you study the motion of a ball, Neil will appreciate this, you have to look at translation, how the ball is moving in a straight line or a curved path. And you have to look at rotation, how the ball is spinning and how that's changing during the shot. All right, so Coriolis, he did all the math and he had to write what are called differential equations to describe these two effects. He solved these equations and he figured out that the direction of friction, you know, when the ball is sliding and skidding across the cloth, there's friction that's trying to slow it down and change the spin. Well, he discovered that the direction of the friction during a shot does not change. It's the same magnitude and same direction during the entire shot, no matter how you hit it. If it's skidding and spinning, it's going to follow.

I mean, the friction is going to be in the same direction for the entire shot. Now, once he discovered that, uh, cause he was smarter than most of us are now, you know, he had, he was creative in how he solved equations. And he, he realized at that point, if the friction is the same force and in the same direction, the whole time, it's going to be just like gravity. You'll like this Neil, cause gravity is always straight down. And when you have projectiles, the force is always in the same direction, the same magnitude. And that's why projectiles follow a parabolic path. Wow, so it's the horizontal version of how gravity works in our environment or here on Earth. I like it. I like it.

That's really cool, man. So there are certain shots where this applies you know anytime you uh you hit the cue ball with top spin or bottom spin by aiming high or low on the ball right after it hits the object ball the ball you're hitting the cue ball starts sliding and then that spin takes over it peels out and makes it curve well that's an example that that curve shape is a parabola right that. That's one place. Another type of shot where the Coriolis aiming system applies. All right, so a massé shot, and a lot of terms in Poole came from the French

because as Gary pointed out earlier, Poole started with the aristocrats in France and England. So a massé shot is a French term where you actually strike down on the ball from above. Maybe you've seen some trick shot artists do this. Yes, yes. Strike down on the ball off center and, you know, to one side and down into the table.

It gives the cue ball a lot of spin. It gives it side spin, and it gives it what's called a barrel roll or kind of a, you know, like imagine a kayak kind of turning or a spaceship spinning, a satellite spinning. It gives it that kind of spin. While it's going forward. Yes, while it's going forward. Corkscrew.

Corkscrew spins is another name for it. All right. So when you hit a masse shot, it also follows a parabolic path. So anytime the cue ball is not going straight or any ball is not going straight, it's always following a parabolic path. That's one thing Coriolis proved. Okay, what's the deal with the jump shot? Wait, wait, wait. So Chuck is taking very careful notes. Oh, no, I alreadyolis proved. Okay, what's the deal with the jump shot? Wait, so Chuck is

taking very careful notes. He has to win back that money. He has to win back some of that money. I wish I could, you know what I mean? By the way, the what's it? Amase shot? Mase. So I'm going to call it the Amase shot.

And that's when somebody does it and they say, Amase, you owe say, I'm going to say you owe me some money. I'm going to say you owe me another $50. And by the way, that shot in a trick shot is where you see guys, normally there's an opponent's ball between your ball and the target ball, between the cue ball and the target ball, between the cue ball and the target ball. And so what you want to do is go around their ball. And that's what that shot does.

It allows you to literally go around the opponent's ball and strike your ball. Chuck, that's why we have Dave on the show. Oh, I'm sorry. By the way, Dave, tell us about that shot. Describe that shot for us. Wallace, when you want to bend the ball around another ball. Okay, thank you.

All right, so now we know where we are literally on the table. If that shot, that Massey shot is blocked because of the cushions, I have to go airborne. Now, how on earth am I getting a stationary ball airborne by hitting down on it? Because- I'll talk about this, but we've got to go back to Coriolis. We've got to go back to Coriolis.

Okay, sure. It's not as if I can bounce it. Yes, yes. So there's, that's called a jump shot in pool. And I mean, some novice beginner players have probably executed jump shots before, but they haven't been the legal type. Right.

The illegal type is where you hit under the ball too low and it scoops up in the air. It's called a scoop shot. That is not legal for several reasons. One, it can damage the cloth. It's actually too easy to do it. It's very easy to do it if you try. So at some point, they wrote rules to prevent that kind of shot, but still allow a jump shot. But now you have to hit down on the ball, and that causes the cue ball to actually compress the cloth and bounce off the slate.

You know, the bed of a pool table is made out of slate, geological slate. And slate's one of those materials in nature that engineers have not been able to beat. There's several materials like that in pool. We should talk about that too. Like tips are still letters. So finish Coriolis. So finish Coriolis. All right. So that's one thing Coriolis discovered, that all paths on the table are parabolic, just like the shape of a reflector in a headlight.

All right. So let's get back to the second discovery that Coriolis found that I was just blown away by. And that's this Coriolis aiming system. All right. I call it the bar system first. Let me tell you why. So imagine a ball. You're hitting a masse shot. So you're hitting down on the ball. So you're aiming at a point

on the ball. That's the B, bar method. If you project your cue, the direction the cue is pointing onto the table, it's aiming at a point on the cloth. All right, that's A, B, A. All right, now you have to, so that's one line. We have a line that's through the cue, hitting the ball, and aiming at a point in the cloth. Well, Coriolis, when he solved all the equations for these masse shots, I don't know how he did it, but he found a way to simplify the math at the end with some crazy geometry. And he found out that a straight line describes the final answer, even though the equations do not look like a straight line.

All right. Now the straight line he found is from the resting point. If you imagine the resting point of the ball, that's the third point R. So we have bar ball, ball point, aim point, resting point. All right. So Coriolis found where the cue is pointing at the cloth. If you draw a line from the resting point in the ball to this point, this aiming point on the cloth, imagine that line, that line shows you the angle,

the final angle that the cue ball will head after it's done curving. Right. Whoa. So I call this the Coriolis aiming system because if you want to aim a masse shot, you know, most people aim them by feel. But when I aim them,

I actually look at the final line I want. I kind of project that line back to the cue ball with my cue stick. I add a little because it's not perfect. There's some imperfections on a pool table. I'd shift the line a little bit and now I know where to aim my tip at the cloth through the ball and I can make that ball curve and follow that final pass. Wow. This is the Coriolis aiming system. Wow, where was this book when I was losing all this money? when I was losing all this money.

So, Dave, we've got terms like English, squirt, throw, and one I could probably understand, swerve. Yes. What do they mean? I mean, because English to me doesn't make sense, but it's very popular here in the US. Aren't you British? Yeah, we say put English on the board. Aren't you British, Gary?

Shouldn't you know it? Yeah, I didn't. Yes, Gary. Not in terms of billiards or pool. There's no such term in the UK. Well, Gary, in billiards, English is where you address the ball and you go, I sailed, man.

I sailed. Actually, it is related to how you address the ball. Where you address the ball with a tip. That's right. Chuck, normally what happens is you have one's butler address the ball with a tip. That's right. Chuck, normally what happens is you have one's butler address the ball on your behalf. Sorry, Dave, you were telling us how it works.

Can I talk now? Yeah. Didn't you guys... Am I supposed to be the guest here? Yeah, he's the guest. You guys are like my Italian family. If you want to be heard, you've got to talk louder and louder and louder. You're getting with the program. All right. So when you hit the ball off center, you impart side spin,

clockwise or counterclockwise spin. All right. Now, in the early days. Just to be clear, that's clockwise or counterclockwise seen from above. Seen from above, yeah. So when you hit the left side of the ball, you're imparting clockwise spin. Yeah. Yeah, looking from above.

Right. So, you know, in the early days, Gary mentioned that pool originated from the aristocrats that, you know, because the weather was so bad in England, they had to put, bring croquet inside. They put it on a table. The balls kept rolling off. So they put these rails on the table. Now, when the balls got close to the rails, you know, the croquet mallet, if you can, it's like a hammer, right? Usually you hit it with the hammer part, the mallet part. But when the balls were close to these rails they put on the tables, they had to turn it around and hit it with the end of the mallet. That's where the pool cue, that's where the pool cue came from. And for many hundreds of years, that pool cue was just a bare piece of wood, just like the end of a croquet mallet. All right. Now with a bare piece of wood, you cannot

hit the ball off center very much. If you do, it slips right off. All right. All right. So in the early 1800s, around the same time of Coriolis, some guy anecdotally decided, because their pool cue kind of cracked on the end, they anecdotally took a piece of leather from their shoe and kind of nailed it onto the end of the cue. I'm not sure how they nailed it, but they got a piece of leather on the end of their tip and allowed them to hit the ball off center now. You know, it's anecdotal, but this is kind of true. You know, that's how that full cue evolved. Somebody put a piece of leather on the end of the tip one day, and now they discovered they could hit the ball off center and apply spin. Now I'm answering Gary's question, where'd the word English come from? All right, because after these leather tips were kind of invented around Coriolis' time,

this English guy came to America and was given these exhibitions. And he had this leather tip on there. Nobody in America had that yet. And this English guy was hitting all these wicked shots, like masse shots, and spinning the heck out of the ball, making the ball dance around the table. Well, the Americans hadn't seen that. They said, look at this English guy hitting these English shots. England. English.

Silence and spin. Okay. Silence and spin. And by the way, the English is so necessary when we talked earlier about where you leave the ball. Right, at the after the shot. After the shot. Now, something we have that's become almost,

we've got to take a quick break in a second, but something we have that's become almost, we've got to take a quick break in a second, but something we have that's almost trope is the person who just sits there and puts the chalk on the tip of the, while they stare, they're not saying anything, they're just putting the chalk on. You know you're going to get ass whooping, right? That's right.

So when did chalk come into this? I guess chalk and slate go together. As an educator, that's what's in the front of a classroom, chalk and slate. Yes. Now, the chalk, it's not – the slate is geological slate, but the chalk is not geological chalk. It kind of looks and feels like it, but it's made differently. It's made from Tums they get from the –

From the heartburn you get by watching a guy chomp your heart. The heartburn. You can eat it while you're losing. As you get the indigestion for losing. It soothes your eyes while you're losing. I mentioned the leather tip. We still use leather. It's been 200 years.

Engineers have not improved on leather. It's just really good stuff. Dead animal skin is the best thing to put on the end of a pool cue. So there's no vegetarian pool sharks. That's what that comes down to. I've had several people ask me if there's a vegan alternative, and there are some, but it's not acceptable to a good people. Yeah, there's a vegan alternative.

It's called losing. That is so blunt. But the chalk is to give the tip more friction. You know, the leather grabs fairly well, but when you add this chalk, which has a bunch of abrasive particles in it, so it's a chalk-like substance that's mixed in with some little abrasive particles, it's kind of like a fine sandpaper. But, you know, when you apply that... Yeah, but is it a different...

Wait, wait, wait. But don't gymnasts use chalk to reduce friction? That's different. That's just to absorb moisture, like talc. Oh, moisture from their palm of their hand. And boulders use a rosin. They use a rosin bag. Same thing, to take moisture off the hands, yes.

I got it, got it. Okay, so let's take a quick break. When we come back, I want to hear a little bit more about trick shots and also some of the culture of what it is to be a billiards shark. StarTalk Sports Edition. We're back. StarTalk Sports Edition. The physics of billiards.

And we have one of the world's experts on who thinks about the physics of billiards. It's Dr. David Alcator. Alcator. Yes. Just call it Alcator. Alcator. You've got to use your hands. You've got to use your hands.

I want to say it that way, and I'm trying to. My body won't let me. Dr. Dave. Use your hands. Just call him Dr. Dave. Dr. Dave. That's how I'm going to do it that way, and I'm trying to, my body won't let me. Dr. Dave, use your hands. Just call him Dr. Dave. Dr. Dave, that's how I'm going to do it. That works. So, Dr. Dave, we all love trick shots.

Do they have any real role in competitive billiards? Yes, there are what are called artistic billiards competitions where the feature is trick shots. Oh, okay. And so are they, I'm curious because in the all-star break in basketball, they have the slam dunk competition. In the all-star break in baseball, they have the home run derby. So these are the fun things that can show up in a regular game. Now they're all focused down into one slot, into one offering. So I guess what I'm asking is,

are there occasions where a completely crazy trick shot would be necessary in competitive play? Yes. In fact, we talked about a masse shot where you try to curve around an obstacle. That is useful in actual play. And that counts as a trick shot. Okay. Yes. Now in trick shots, they do very dramatic versions of that.

But in an actual game, if you seem to curve a little bit, a few inches, you can do that pretty, pretty reliably. And a lot of trick shots, they involve a pre-setup of what the balls look like on the table. Bingo. Yeah. So that makes it, is the art of the setup so that your ball can do what it needs to. And the other trick shot is the jump shot, you know, which we started talking about before. We hit the ball at a downward angle, causing it to compress the cloth, bounce off this natural slate. And that's a legal jump shot.

I didn't finish that thought earlier. It's a legal jump shot. You can make the cue ball bounce over an entire obstacle ball. And this is a very important weapon in modern pool. So what are the balls made of to enable them to do this? They're made out of a phenolic resin. It's a thermoset material, it's called, but it's a phenolic.

It's called a phenolic... It's a resin. A phenolic resin. I know, but Dave, historically, weren't they made of ivory? Yes, and I have to collectively apologize for my entire sports history because we killed lots of elephants in the past.

And the real sad part of the story is that you only got about three balls out of one tusk. Oh, no. Can you imagine how many elephants had to die to help this sport? Yeah. Now, we talked about the slate and the leather tip that engineers haven't been able to improve upon nature's incredible evolutionary feats. But the ball, we did find a better alternative to ivory. What about the cue? I mean, are we stuck in historical tradition and it's wood only or have we made any advances there?

Well, since the 1400s, it's been a wood cuisse, just like that original croquet mallet. And just in recent years, in the last 10 or so years, has carbon fiber come out. And there's been other attempts in the past with fiberglass and aluminum, but they just did not sell. And you couldn't play well with them. Carbon fiber is the first true revolution in pool equipment. Otherwise, nothing has changed. Nothing has changed in hundreds of years.

Yeah, but wait, Dave, if you're trying to hit the ball, some of what matters is the momentum that the cue stick has that you're imparting on the ball. And if you go to carbon fiber, which is obviously lighter than wood, in order to get the same momentum, I have to push the stick harder into the ball. And maybe I don't want to do that. Maybe I just want a heavier bat, as we'd say in baseball.

So what is the carbon fiber doing for you? Well, the only thing that's made of carbon fiber is the shaft, the front end of the cue. Right. You know, most good cues are in two pieces, the shaft and the front piece. Yeah, I see. When a dude walks in the pool hall with a suitcase and opens the suitcase and attaches one piece to the other, that's when it's time to say, okay, you win.

I've won. These are people not using the company cue sticks on the thing. They got their own. From our conversation so far, as Chuck said it quite succinctly, it's all about the lead. But how many shots ahead is a high-end pooled billions player actually mentally calculating? Ooh, yes. That's a great question. No, no, no. We got to say that differently. How many are they capable of knowing given the chaos and the randomness of what happens on the phone? Oh, man, this is great. Cool table.

Go ahead, Dave. Great question. Great question. Yeah. And by the way, Neil, a good player does not experience much chaos or randomness. Excuse me. But the answer depends on the game you're playing, partly. So I did want to mention, you know, eight ball is the most common game in America.

Most people know what that is. You have to hit the solids or the stripes first, then pocket the eight. The other common game— america most people know what that is you have to the solids or the stripes first then pocket the eight the other nine ball is where the action is baby sorry wait it's the only game ever where the black thing is last rather than first off the table yes yeah yeah but the white the white ball still controls everything very racist game very racist very game. Very racist. Okay. Forgive me for forgetting that fundamental fact. Okay. So the other game, nine ball,

that's the game of choice in pro tournaments now. And it's also historically the gambling game. That's why Chuck knows it from his misspent youth. Yeah. Yeah. So the thing is, you've probably seen them. Guys just turn up, grab a cue, and they intuitively know what they're doing. You kind of see it with some other athletes,

but what are they calculating? You know, what sort of geometry are they able to see and feel just without having a scientific education? Well, you say it looks intuitive, but they are thinking about a lot. They just do it very quickly. And they're not thinking about, and even I don't think about physics and geometry when I'm at the table, except in certain shots.

I do have geometric systems for aiming certain types of shots, like bank shots and kick shots where you're getting balls off rails. Then the geometry can help, but you still have to adjust for the real-world physics on a pool table. The pure geometry does not work by itself. But anyway, good players don't think about any of that. They just, they instinctively know how to aim, first of all. And, but when they're planning, they are doing a lot of planning.

And they always think at least three balls ahead, especially not in- Three shots ahead. Always. Yeah, okay. Now in a game like eight ball, you often have to think through everything. If you're playing at a high level, you have to think about the whole game and work a game like eight ball, you often have to think through everything if you're playing

at a high level. You have to think about the whole game and work backwards from the eight ball. You got to first see where can the eight ball go? What should I choose, solids or stripes? Well, if the stripes are blocking the eight ball, then you probably have to shoot stripes because otherwise the eight ball can't go in anywhere. So you always think backwards and then you have to say, well, the eight ball's here. These other balls are in the way. Once I clear all my other balls, where do I have to get the cue ball to make that eight ball? So you got to think about what is the key ball to help me get on the eight? That's the last ball you pocket, the last stripe or solid you pocket to get shape on the eight.

That's the leave you talked about before, Chuck, the shape. That's right. And sometimes what happens is you don't have a shot to move forward. So what you want to do then is play some defense to make sure that your leave puts your opponent at a disadvantage so that you're not leaving them with three shots that they could then go ahead and maybe go ahead and sink the eight ball on you.

Chuck, given your legendary billiard debt, why are we listening to any advice from you at all? I just want to make this clear. I just want to be clear about this. Do what I do, not what I say. I mean, do what I say, not what I do. So let me ask you about... We just have a couple more minutes, Chuck.

Okay, very quickly. It's not a trick shot, but multiple bank shots, which are, to me, one of the coolest things that you can see when you're playing pool. You know, a bank shot is a bank shot. But, like, when you have a ball hidden and you go two banks and then a third bank off the rail and just kiss it and knock the ball in, that kind of stuff is like... So, when you're picking your spots, how do you maintain the sight for all three spots? Because the first one-

And let me jump in here and say, I'm going to jump in here and say, when you see the projected paths of hurricanes and the farther along the path of the hurricane, the wider is the uncertainty, you know that's going on on Dave's pool table. So let me ask you, Dave, how big does your uncertainty get? Even if you're highly talented at this, as it goes from one cushion to another cushion, and that third cushion has got to have maximal uncertainty in where you expected it to go? Well, there's actually systems for aiming these types of shots. And what you're describing, Chuck, is called a kick shot. You know, when you hit an object ball, like a target ball, and you make it bounce off a rail, that's called a bank shot. But when you hit one or more rails

first with the cue ball, that's called the bank shot. But when you hit one or more rails first with the cue ball, that's called the kick shot. So there are several systems that are called diamond systems. You know why they're called diamond systems? No. Because there's diamonds on the table, on the rails. Oh, okay. They're at the between points of the pockets.

Is that what they're there for? That's what they're there for, to help aim certain types of shots. And that's what you focus on. You focus at where you're shooting relative to the diamonds on the first rail. Okay? Now, these diamond systems, they were developed many years ago, hundreds of years ago. And, you know, when we had this other game called billiards, we talked about, you know, pool is pocket billiards.

Our tables have pockets in them. But the original billiards had no pockets. In fact, I don't know if you know the musical, The Music Man, you know that? Yeah. Right here in River City. You got it, right? We got trouble, we got trouble.

You know what, you know what? That starts with T and that rhymes with P. That stands for pool. That stands for pool. The whole theme of that musical was that- Chuck, very good. Good job, Chuck, I'm impressed, I'm impressed. Yeah, yeah. So the whole thing the whole thing that musical is that uh chuck very good good job chuck i'm impressed i'm impressed yeah so the whole theme of that musical was that this billiard parlor which was a very gentlemanly game because it was in there only there were only three balls

on the table no pockets the goal is to hit the first ball and before you hit and you had to hit the first ball into the second ball you're hitting a cue ball and there's two other balls so you hit the cue ball into the first ball before the cue ball hits the second ball. You're hitting a cue ball, and there's two other balls. So you hit the cue ball into the first ball. Before the cue ball hits the second ball, you have to contact at least three rails. That's the game. That's billiards. That's billiards.

So those folks know the geometry real well. Yes, and they came up with these systems to aim those types of shots. Now, the theme of this musical was that the billiard parlor in town was about to install an American pool table. And that was going to corrupt the youth of this musical was that the billiard parlor in town was about to install an American pool table. And that was going to corrupt the youth of the town. So they needed something wholesome.

They needed something wholesome to replace that corruption. And it was a marching band. They needed 76 trombones. Yes, exactly. That's what they needed. Anyway, what were we talking about? I forget. I don't know.

I was talking about the diamond system. The diamond systems for aiming kick shots. Wait, so wait. It tells me then that diamonds are a start. In some version of a pool table, you could completely calibrate all sides of the table down to a millimeter. Yes.

Why not? Yes. You could? Yes. I don't need just one thing that divides it in two. Give me something that divides it into a thousand parts. I could. Yes. Yeah. I don't need just one thing that divides it in two. Give me something that divides it into a thousand parts. Oh, I see what you're saying.

Yeah. That would up my game, the precision of my game. And if you're teaching kids math, and they'll say in middle school, say, I'll never need to know that for the rest of my life. I say, yes, you will. Okay. If you don't want to end up like Chuck,

losing all your money. The cautionary tale of tough nights. Well, we only have, you know, we have eight diamonds on the length of the pool table, and there's four on the side. But pool players, we can specify numbers in between those diamonds. So I'll say this is at 1.15, or, you know, it's between the first and second diamond. I'll say 1.7. So we can find two.

And people can learn about fractions and decimals that way too. We've got to actually land this plane as we try to do. Let me offer some final reflective comments. Any astrophysicist older than 50 never challenged them to pull because if you're over that age, you would have visited telescopes in your day. After that, it's remote observing because everything is done electronically now.

But at telescope domes on cloudy nights, every mountain telescope has a pool table. And on cloudy nights, you have to be on call in case the clouds part, everyone is playing pool. We are all badass. Well, we're not world class, but we're better than you think. We're better than average. And so this is an alert for all pool sharks out there.

Watch out for astrophysicists. I like it. I think a lot of people would have spent much more time paying attention in their geometry class and in their physics class had they known about your pool tables. I'm pretty sure. So tell us, where do we find you online? We know you have, where do we find you on Facebook? Yeah, people want to see some videos

that demonstrate a lot of this stuff. I do. I have a Facebook page, it's Dr. Dave Billiards. I have a YouTube channel, Dr. Dave Billiards. I have a website, drdavebilliards.com, where I sell my book, my videos, T-shirts, all kinds of stuff. Cool, cool. I have another website, drdavebilliards.com, where I sell my book, my videos, t-shirts, all kinds of stuff. I have another website, which is probably of the most interest. It's billiards.colostate.edu. That's all free stuff. I have thousands of videos,

thousands of articles, or hundreds of articles I've written for Billiard Magazine. Okay. So that's your academic pivot point for your life's output. Very good. Very good. your academic pivot point for your life's output. Very good. Very good. All right. We're actually done here. David, it's great to have you on. And I'm always pleased to learn that they're complete experts in things that we don't otherwise think would have experts or would even deserve experts. And there you are bringing the science down to earth. Thank you, Neil. And that's what that's what we try to how we try to roll here on StarTalk. Gary, Chuck, always good to have you. And Chuck, now I understand, Chuck,

why you keep asking for a raise. It's to get out of debt. We'll visit you in prison, Chuck. All right, guys. I'm Neil deGrasse Tyson, signing off for StarTalk. As always, keep looking up.