My son is the best example of Brownian Motion on earth. When he starts running around and hits random objects and people there is no other description that I can think about.
The fascinating bit occurs when you fiddle with the parameters of Brownian motion - the Hurt index - to get structured noise that can be very useful (and just plain weird) for modeling natural growth patterns.
0:27 He wasn't any old Roman, he was the great poet and atomist philosopher Titus Lucretius Carus, the man who first identified Brownian motion and correctly deduced from it the existence of atoms.
Einstein's Miracle Year is something beyond comprehension. Special relativity. E=MC^2. Photoelectric effect (for which he won his Nobel Prize). Brownian motion. All explained by one man in one year. Brownian motion is easily the one that gets overlooked the most. As a chemical engineer, it's very important, though, because at low Reynolds Numbers, the Einstein Relation simplifies to the Stokes-Einstein equation, which fundamentally describes the vertical movement of gas bubbles in a liquid. Or particles of any phase moving through another bulk phase. That's key to determining size of any piece of equipment where gravity plays a role in separating a gas from a liquid, a liquid from another immiscible liquid, or small solid particles from a gas or a liquid. So behind the scenes, Einstein's explanations of Brownian motion play a direct role in the manufacturing of almost every chemical you see in your daily life.
Einstein is the greatest scientist to ever live, and is perhaps the most original genius science has ever produced. Most historians of science agree that he SHOULD have gotten the nobel prize for his brownian motion paper which in fact DOES explain brownian motion Einstein is the father of condensed matter physics too. If ANYTHING Einstein doesnt get enough credit for founding quantum theory. Einstein's work on the specific heat of solids should have won him another nobel prize. Einstein essentially discovered matter waves - the same Equation Einstein used for photons De Broglie used but applied it to electrons. Einstein's work on the BOSON (which should be called the Einsteinion seeing as it was Einstein who discovered this phenomenon not Bose). He did so many things that largely went under appreciated. He discovered THE equation for wave-particle duality 13 years before De Broglie did. His work on Stimulated and Spontaneous Emission, the foundation of LASER theory, should have netted Einstein another nobel prize. We still use the Einstein A and B Coefficients in steady state physics even today. Without Einstein, you cannot explain the Dulung-Petit law and the temperature of diamond. Without Einstein you don't have quantum entanglement - he was the one that discovered it in the EPR paper. According to head of applied physics at Yale University, Douglas A. Stone, Einstein should have received 7 - 10 Nobel prizes for his contributions to fundamental physics. Mind-blowing genius indeed. Incredible what one mind could do. Schrodinger never discovers the Schrodinger Equation (the wave function) without Einstein's help, and Max Born never wins the Nobel Prize without Einstein's help - both of which they have stated on the record. UA-cam deletes links but type in "Douglas Stone Albert Einstein Huffington Post" into a Google search and you'll find the article in which he credibly argues that Einstein really should have won at least 7 Nobel Prizes. Incredible genius. And then you remember he also did General Relativity which would, alone, make any other scientist a top 3 scientist to ever live.
The machine is a speaker put on its side. A block of rubber (or other material) is placed into the concave portion of the speaker (to flatten the working surface). All you would need is the speaker, a box to house the speaker, an amplitude / frequency generator (to create a constant vibration), and maybe the block (this part is optional, depending upon your experiment). Hope this helps.
I'm not a physicist but we also learned about Brownian motion (or Wiener process) on Financial mathematics, and on Stochastic processes course as well. So it's pretty widely used I guess.
Cameron Costanzo You probably have seen the economic curves. Those zigzag lines. In fact those are called brownian curves. A continuous line that is not differentiable.
Fightclub1995 I dare say there are many such lines. In fact I think you have the space C naught described perfectly. Is there a more specific trait for Brownian curves?
The principle of uncertainty regarding the position and momentum of particles/waves is a special kind of uncertainty - a theoretically irreducible one. Random variables may be used to describe certain or uncertain things. Random motion of real objects includes irreducible uncertainty. Because it is chaotic, Brownian motion makes these small uncertainties become large displacements over time. So, it's accurate to call this motion random and uncertain as the professor pointed out.
If you mean like the ones responsible for Brownian motion, then yes, at least in any familiar environment. Brownian motion is, to my understanding, the effect of the generally random motion of atoms on a small particle in a fluid. Dust in the air and pollen in the water, all that jazz. So a tiny random force is exerted by the movement of the atoms in the air and water on any object immersed in those fluids.
Einstein didn't say in 1905 "Random forces cause brownian motion", actually he didn't talk about Brownian Motion itself either.. He spoke about diffusion of colloid suspensions in a liquid and get an expression for D, coefficient of diffusion, and then said "It's possible that the movement I wrote about are identical to brownian motion, but I don't know"
Thank you !!! It really bothered me when he said that Einstein introduced the random force. Einstein contributed a lot to the theory of brownian motion, but it was Smoluchowski that first associated brownian motion with the concept of a random walk and Langevin that first introduced the idea of a random force.
Einstein is the greatest scientist to ever live, and is perhaps the most original genius science has ever produced. Most historians of science agree that he SHOULD have gotten the nobel prize for his brownian motion paper which in fact DOES explain brownian motion Einstein is the father of condensed matter physics too. If ANYTHING Einstein doesnt get enough credit for founding quantum theory. Einstein's work on the specific heat of solids should have won him another nobel prize. He did so many things that largely went under appreciated. He discovered THE equation for wave-particle duality 13 years before De Broglie did. His work on Stimulated and Spontaneous Emission should have netted Einstein another nobel prize. We still use the Einstein A and B Coefficients in steady state physics even today. According to head of applied physics at Yale University, Douglas A. Stone, Einstein should have received 7 - 10 Nobel prizes for his contributions to fundamental physics. Mind-blowing genius indeed. Incredible what one mind could do.. UA-cam deletes links but type in Douglas Stone Albert Einstein Huffington Post into a Google search and you'll find the article in which he credibly argues that Einstein really should have won at least 7 Nobel Prizes. Incredible.
I learn more (and understand better) about phisics with your videos that I did in years of conventional learning in school. Of course, we didn't have internet back then. And please take notice that I am from Romania (although currently living in Madrid)
Professor Bowley, That is an excellent presentation. Thank you for it. Q 1. How would Brownian motion be like in a free-falling lab? Q2. Would I be right if said that outside a free-falling lab, a pollen cannot be said to be moving in "random directions" technically as it has a final direction which is "downward". So not all 6N have equal probability outside a free-falling lab so that means Brownian motion cannot said to be random or unpredictable as we know the direction the pollen is always heading and that is "down" no matter what trajectory it takes. Peace
Question- In the top down view, the ball seem to be moving towards the area with more movement, which is a bit counter intuitive, because you would expect it to be bounced away from there. Is the whole thing just tilted a little bit to the side?
@gallardoelise where the layer of grains is thinner, more force from the bottom is distributed to the grain, so yes, the ball is more likely to jump in that direction. and yes, if everything was perfectly aligned, probably the ball would stay in the center. but for that to happen, every bump of every grain to it's surrounding grains and the bump from the plate onto the bottom grain would always have to be exactly like before, so the sphere's always hit each other in exactly the same spot...
As he says that the end, it isn't actually random, it's just that the motion is so chaotic that it become unpredictable. True randomness depends on whether or not you consider the universe to be deterministic (no random) or not. I suppose you could say that all objects in our universe have a random force applied to them at all times, because gravitation from all the other objects in the universe is in effect.
Well for a finite number of particles and therefore a finite number of possible outcomes, there will also be a finite, albeit increasingly large, number of outcomes, scaling exponentially per particle ( or in this case per ball ). A brute force method of computing could eventually predict every single outcome, but since there are different probabilities for events in such a system, it would be very difficult to determine which would actually occur and in what order.
A better description of this would be deterministic chaos or the butterfly effect where a small change in a nonlinear deterministic system can result in large changes at a later measured stage. Even if the bronze grains could be positioned identically every time and the ball placed in exactly the same position, likely the vibration mechanism would not operate on the particles the same or surrounding air molecules would affect the resultant outcome for each trial.
@Cezarijus it does, but a small thing like a pollen seen under a microscope shows a similar movement. that's how they got the idea of the brownian motion of atoms in the first place.
A lot of people are saying "There's no such thing as random" I'd like to know where these people got their PhD's in thermodynamics from, because Roger Bowley here is a Professer, and knows more than you do on these matters.
word limit i removed part about vacuum of air vibrating in cylinder also keeps ball to the side it may possibly give poly static charge as well ! which react to magnet in the speaker
I'm not exactly sure but I imagine it has something to do with the fact that when the polyurethane ball is up against the wall of the container it keeps getting battered against that wall since there are no bronze pellets hitting the polyurethane ball on the other side.
Does container shape effect random motion? For example, does gas within in a very narrow tube display non random motion, but rather motion influenced by possibilities allowed by the walls of the container?
@XxVizzinixX Once the ball is at a side, it will mostly be hit from particles from the centre side, the other side being a glass wall. So once it's there, it won't tend to move back.
Just love the ending, a really usefull tip. When confronted by determinists, invoke quantum mechanics :D The wave function and quantum superposition combined with Heisenbergs uncertainty principle should be enough to shut any determinist up.
Why is it the white blob must be put in the center? Does it always travel from the center outward, never returning? Is that because the center is has slightly more vibrating action than the sides?
I guess the density of the white ball looks less than that of the grains underneath it. I guess they would need to be more similar for entropic driven organization to occur.
The most amazing work of Einstein's career was the 8 or 9 years he spent developing the General Theory of Relativity. The 1905 papers were all worthy of Nobel Prizes and were greater achievements than most Nobel laureates would ever make, but his General Theory is what places him as one of the greatest of all time... comparable to Newton.
The problem was that I had planned to do the experiment in the laboratory and I forgot that there was a class there so the video was recorded with me surrounded by students, and with Prof Peter Kroger who was running the class. I was worried that the students would ruin the video (they didn't) and was asking Brady if he had enough material for a video. That's why I asked Brady "Have I finished." Stupid of me because he was then able to leave it in.
@htomerif I have no idea, but couldn't there be larger molecules in the water being buffeted by the H2O which are in turn buffeting larger molecules etc up to the pollen?- Also i believe there are many different types and sizes of pollen- so it probably depends which type you are measuring.
What would happen if you had about 10 of the white spheres...I just wonder if they would clump together so that the motion of the little spheres is maximized. Would love to see this tested.
Can someone expand on his reference to a "Roman person", is there any famous text describing that observation of dust? or is he is just making that up?
random is just a word we use cus its very very very hard to predict how sand particle would move in the wind for example .....so its easier to call it random.
The Roman Lucretius's scientific poem "On the Nature of Things" (c. 60 BC) has a remarkable description of Brownian motion of dust particles. He uses this as a proof of the existence of atoms:
its because these position of molecules in the air are random, so when the atoms vibrate they move around the larger molecules in the air like dust in a random motion. but that's my theory
Proof of theoretical continuity because perfectly numerical discreteness would be inflexibly phase-locked, so coherence-cohesion is Reciproction-recirculation logarithmic continuous spectrum of Bose-Einsteinian QM-TIME Condensation phase-locked states of chemical bonding compositions.
frequency's should be able to control direction on flat surface but coil from speaker used is pulsed from centre so it will eventually push it out to side no matter the frequency or or how smooth the surface is ? another variable is !ramp effect vibration cause larger objects to surface and smaller to sink eventually separate/sorting them into layers based weight first then mass second ,but in lowest layers are the larger mass pulled towards or pushed away from centre by the pressure above ?
I think the little device used in this video is just an analogy of what happens at atomic levels. So far I know, there is no way to predict without uncertainty the behavior of particles at that scale, so, for all useful purposes you can safely say the brownian effect is random.
so you think you could accurately predict how it will move? where i live, most days are sunny and it only rains occasionally, does that mean the wheather is not random but instead follows a pattern?
@VanderWolls Appeal to authority. I'm not saying that you're wrong though. However, to me it appears like that professor Browley say that it should be possible to work it out in a deterministic manner from 5:00 onward. To me it seems like Browleys own objection against the deterministic approach is that all starting conditions can't be specified.
Is it me or the example is a bit flawed? We know the ball will tend to move towards the edge of the glass because it's contained. My guess the kinetic energy is not transferred as it should be if it were on a huge platform. Has anyone tried this on a huge vibrating bowl, say 1km? I'd like to see what happens!
The first time I saw that I thought it was the bronze hitting of center from underneath and that was pushing I didnt realize it was hitting it on the side.
White Fox I think your first observation was right. It looks like the vibration is in the vertical direction and most of the bronze pellets just go up/down. When they hit the polystyrene ball off center, the normal force will have a horizontal component, causing it to change horizontal motion.
Yeah, I did notice that also. This particular experiment shows the general idea and is a little far from an ideal experiment where the motion of each bead is practically the same.
we are not arguing over the symantics of the word random are we? i'm defining random as meaning unpredictable. am i mistaken? if so, why? or are you saying it means unpredictable in practice but in theory would be predictable if you could analyze ALL the data?
@bugilt there are as many good solutions to random number generation in computers as there are needs for the randomness of said number. From NSA approved nuclear decay to the parametric clock based randomness that's good for everyday uses.
Surely though, wouldn't it be possible to somehow scan the position and variations of each of the bronze particles in the jar and the position of the 'pollen', in an extremely well controlled environment, and then run it through a simulator in a super computer and get the same results as if you tested it?
Some things are inherently unpredictable, and at some level the accuracy of your measurements would reach a limit. IOW, even if you know the all the particulars about a system, you still can't predict the future of it.
It is not impossible to measure, but we simply do not want to take our time to measure. Some people spend money without thinking and when they look at the bottom line, they think that what lead to it was random. What I am trying to say is thar the threshold where we give up counting and accept “randomness” seems to be arbitrary.
To be honest, with a beyond-exascale computer, you could probably model it with a fair degree of accuracy. Would be interesting to see what results it actually threw out taking into consideration quantum mechanical effects.
The granularity of brownian motion would seem to suggest that it's possible to reverse entropy. To take out all the energy from thermal movement. Am I wrong?
+Dan Frederiksen Interesting!After a bit of googling around it seems that ALL equations in current physics models are reversible in time, EXCEPT for some instances of the second law of thermodynamics... I don't fully understand it (or have time to research) but here is a little wiki link if you'd like to do more research on the matter en.wikipedia.org/wiki/Irreversible_process
I think of entropy as a result of the arrow of time only moving in one direction. If you could reverse time you could reverse the increase in entropy over time. Would that happen if you chilled some particles to absolute zero?
no, there is chaos too. chaos doesnt mean that we dont know all the variables. chaotic movement has literal chaos in it. what you said is true for classical physics.
Did anyone else notice that about half of the bronze beads in the container move a lot less than the other half? And that the styrofoam ball tend to go to where there is the most movement? It somehow seems a little bit less random to me! Could someone please explain this? (or an idea for a future video, Brady @sixtysymbols ), Cheer's, Ole
I'm confused. I threw some math at it to see what stuck, and using 3000 grains per mg for pollen, you end up with a pollen grain being 1.1*10^16 more massive than a molecule of water. Wouldn't a single molecule of water "banging" into a pollen grain have to have an enormous velocity to make it move visibly even under a microscope? I mean, I guess not, but its still hard to understand.
@gomunkul You are quite right. The thing is, science requires emprical evidence, you can't just get it all from your own head. The prof here has spent his career studying the topic matter, and would have seen an extream amount of experimental data, and spent years studying relevent calculations. I just think people should first ask him: "What makes you say that?", and when he explains his reasoning, then consider whether you agree with his conclusions. I don't think we should follow blindly.
@systematic101 Thats what you would think, but this would imply some kind of larger order coordinated movement of molecules than simply on the single molecule level, even if the coordination is only for brief times and on microscopic levels. I would actually have a few questions about that to ask a physicist well versed in that subject, though I don't know any.
My son is the best example of Brownian Motion on earth. When he starts running around and hits random objects and people there is no other description that I can think about.
Maybe it's because he is a kid and doesn't take enough care?
Professor Bowley invokes quantum mechanics! It's super effective!
Have I finished?
*clap clap* well played.
That was helpful. Thank you.
I don't always invoke quantum mechanics, but when I do it shuts everyone up.
have i finished?
Professor Bowley always has little moments like at 5:12 to 5:21 that I just love watching his videos for.
"Have I finished?"
Nice cover pic look at the buddahbrot too.
Indeed, we're on our "second sixty" now... more details at the sixty symbols website!
The fascinating bit occurs when you fiddle with the parameters of Brownian motion - the Hurt index - to get structured noise that can be very useful (and just plain weird) for modeling natural growth patterns.
+Jaye Bass Hurst with an s ...made me look..:)
Terrific explanation, Professor Bowley. Thank you.
Professor Bowley is like pink noise - naturally awesome.
Kay Dubbleyuh i
0:27 He wasn't any old Roman, he was the great poet and atomist philosopher Titus Lucretius Carus, the man who first identified Brownian motion and correctly deduced from it the existence of atoms.
Einstein's Miracle Year is something beyond comprehension. Special relativity. E=MC^2. Photoelectric effect (for which he won his Nobel Prize). Brownian motion. All explained by one man in one year.
Brownian motion is easily the one that gets overlooked the most. As a chemical engineer, it's very important, though, because at low Reynolds Numbers, the Einstein Relation simplifies to the Stokes-Einstein equation, which fundamentally describes the vertical movement of gas bubbles in a liquid. Or particles of any phase moving through another bulk phase. That's key to determining size of any piece of equipment where gravity plays a role in separating a gas from a liquid, a liquid from another immiscible liquid, or small solid particles from a gas or a liquid. So behind the scenes, Einstein's explanations of Brownian motion play a direct role in the manufacturing of almost every chemical you see in your daily life.
Einstein is the greatest scientist to ever live, and is perhaps the most original genius science has ever produced. Most historians of science agree that he SHOULD have gotten the nobel prize for his brownian motion paper which in fact DOES explain brownian motion Einstein is the father of condensed matter physics too. If ANYTHING Einstein doesnt get enough credit for founding quantum theory.
Einstein's work on the specific heat of solids should have won him another nobel prize. Einstein essentially discovered matter waves - the same Equation Einstein used for photons De Broglie used but applied it to electrons. Einstein's work on the BOSON (which should be called the Einsteinion seeing as it was Einstein who discovered this phenomenon not Bose). He did so many things that largely went under appreciated. He discovered THE equation for wave-particle duality 13 years before De Broglie did. His work on Stimulated and Spontaneous Emission, the foundation of LASER theory, should have netted Einstein another nobel prize. We still use the Einstein A and B Coefficients in steady state physics even today. Without Einstein, you cannot explain the Dulung-Petit law and the temperature of diamond. Without Einstein you don't have quantum entanglement - he was the one that discovered it in the EPR paper.
According to head of applied physics at Yale University, Douglas A. Stone, Einstein should have received 7 - 10 Nobel prizes for his contributions to fundamental physics. Mind-blowing genius indeed. Incredible what one mind could do. Schrodinger never discovers the Schrodinger Equation (the wave function) without Einstein's help, and Max Born never wins the Nobel Prize without Einstein's help - both of which they have stated on the record.
UA-cam deletes links but type in "Douglas Stone Albert Einstein Huffington Post" into a Google search and you'll find the article in which he credibly argues that Einstein really should have won at least 7 Nobel Prizes. Incredible genius.
And then you remember he also did General Relativity which would, alone, make any other scientist a top 3 scientist to ever live.
Great addition to the video on Granular Dynamics! Thank you!
The machine is a speaker put on its side. A block of rubber (or other material) is placed into the concave portion of the speaker (to flatten the working surface). All you would need is the speaker, a box to house the speaker, an amplitude / frequency generator (to create a constant vibration), and maybe the block (this part is optional, depending upon your experiment). Hope this helps.
I'm not a physicist but we also learned about Brownian motion (or Wiener process) on Financial mathematics, and on Stochastic processes course as well. So it's pretty widely used I guess.
How can brownian motion be applied to finance? I'd love to know.
Cameron Costanzo You probably have seen the economic curves. Those zigzag lines. In fact those are called brownian curves. A continuous line that is not differentiable.
Fightclub1995 I dare say there are many such lines. In fact I think you have the space C naught described perfectly. Is there a more specific trait for Brownian curves?
I love the question at the end. 'have I finished.'
The principle of uncertainty regarding the position and momentum of particles/waves is a special kind of uncertainty - a theoretically irreducible one. Random variables may be used to describe certain or uncertain things. Random motion of real objects includes irreducible uncertainty. Because it is chaotic, Brownian motion makes these small uncertainties become large displacements over time. So, it's accurate to call this motion random and uncertain as the professor pointed out.
If you mean like the ones responsible for Brownian motion, then yes, at least in any familiar environment. Brownian motion is, to my understanding, the effect of the generally random motion of atoms on a small particle in a fluid. Dust in the air and pollen in the water, all that jazz. So a tiny random force is exerted by the movement of the atoms in the air and water on any object immersed in those fluids.
In respiratory care "this is the primary mechanism for deposition of small particles (
Einstein didn't say in 1905 "Random forces cause brownian motion", actually he didn't talk about Brownian Motion itself either.. He spoke about diffusion of colloid suspensions in a liquid and get an expression for D, coefficient of diffusion, and then said "It's possible that the movement I wrote about are identical to brownian motion, but I don't know"
Thank you !!! It really bothered me when he said that Einstein introduced the random force. Einstein contributed a lot to the theory of brownian motion, but it was Smoluchowski that first associated brownian motion with the concept of a random walk and Langevin that first introduced the idea of a random force.
Einstein is the greatest scientist to ever live, and is perhaps the most original genius science has ever produced. Most historians of science agree that he SHOULD have gotten the nobel prize for his brownian motion paper which in fact DOES explain brownian motion Einstein is the father of condensed matter physics too. If ANYTHING Einstein doesnt get enough credit for founding quantum theory.
Einstein's work on the specific heat of solids should have won him another nobel prize. He did so many things that largely went under appreciated. He discovered THE equation for wave-particle duality 13 years before De Broglie did. His work on Stimulated and Spontaneous Emission should have netted Einstein another nobel prize. We still use the Einstein A and B Coefficients in steady state physics even today.
According to head of applied physics at Yale University, Douglas A. Stone, Einstein should have received 7 - 10 Nobel prizes for his contributions to fundamental physics. Mind-blowing genius indeed. Incredible what one mind could do.. UA-cam deletes links but type in Douglas Stone Albert Einstein Huffington Post into a Google search and you'll find the article in which he credibly argues that Einstein really should have won at least 7 Nobel Prizes. Incredible.
Einstein was into everything!
Hello sixtysymbols,
I was wondering if you could provide the equations with which Einstein related Newtonian mechanics to thermodynamics. Thank you~
I learn more (and understand better) about phisics with your videos that I did in years of conventional learning in school. Of course, we didn't have internet back then. And please take notice that I am from Romania (although currently living in Madrid)
Professor Bowley, That is an excellent presentation. Thank you for it. Q 1. How would Brownian motion be like in a free-falling lab? Q2. Would I be right if said that outside a free-falling lab, a pollen cannot be said to be moving in "random directions" technically as it has a final direction which is "downward". So not all 6N have equal probability outside a free-falling lab so that means Brownian motion cannot said to be random or unpredictable as we know the direction the pollen is always heading and that is "down" no matter what trajectory it takes. Peace
Question- In the top down view, the ball seem to be moving towards the area with more movement, which is a bit counter intuitive, because you would expect it to be bounced away from there. Is the whole thing just tilted a little bit to the side?
No reply, lol.
Shhhhhh, lol
@gallardoelise where the layer of grains is thinner, more force from the bottom is distributed to the grain, so yes, the ball is more likely to jump in that direction.
and yes, if everything was perfectly aligned, probably the ball would stay in the center.
but for that to happen, every bump of every grain to it's surrounding grains and the bump from the plate onto the bottom grain would always have to be exactly like before, so the sphere's always hit each other in exactly the same spot...
As he says that the end, it isn't actually random, it's just that the motion is so chaotic that it become unpredictable. True randomness depends on whether or not you consider the universe to be deterministic (no random) or not.
I suppose you could say that all objects in our universe have a random force applied to them at all times, because gravitation from all the other objects in the universe is in effect.
He wasn't angry. he was just making sure that he had covered it all.
Well for a finite number of particles and therefore a finite number of possible outcomes, there will also be a finite, albeit increasingly large, number of outcomes, scaling exponentially per particle ( or in this case per ball ). A brute force method of computing could eventually predict every single outcome, but since there are different probabilities for events in such a system, it would be very difficult to determine which would actually occur and in what order.
A better description of this would be deterministic chaos or the butterfly effect where a small change in a nonlinear deterministic system can result in large changes at a later measured stage. Even if the bronze grains could be positioned identically every time and the ball placed in exactly the same position, likely the vibration mechanism would not operate on the particles the same or surrounding air molecules would affect the resultant outcome for each trial.
@Cezarijus it does, but a small thing like a pollen seen under a microscope shows a similar movement. that's how they got the idea of the brownian motion of atoms in the first place.
A lot of people are saying "There's no such thing as random"
I'd like to know where these people got their PhD's in thermodynamics from, because Roger Bowley here is a Professer, and knows more than you do on these matters.
word limit i removed part about vacuum of air vibrating in cylinder also keeps ball to the side it may possibly give poly static charge as well ! which react to magnet in the speaker
I'm not exactly sure but I imagine it has something to do with the fact that when the polyurethane ball is up against the wall of the container it keeps getting battered against that wall since there are no bronze pellets hitting the polyurethane ball on the other side.
Does container shape effect random motion? For example, does gas within in a very narrow tube display non random motion, but rather motion influenced by possibilities allowed by the walls of the container?
@XxVizzinixX Once the ball is at a side, it will mostly be hit from particles from the centre side, the other side being a glass wall. So once it's there, it won't tend to move back.
Just love the ending, a really usefull tip.
When confronted by determinists, invoke quantum mechanics :D
The wave function and quantum superposition combined with Heisenbergs uncertainty principle should be enough to shut any determinist up.
I love these videos, and also, I have that same shirt!
Why is it the white blob must be put in the center? Does it always travel from the center outward, never returning? Is that because the center is has slightly more vibrating action than the sides?
what gives the energy to start Brownian motion in the first place? And why are the collisions ellastic (or are they really not)????
I guess the density of the white ball looks less than that of the grains underneath it. I guess they would need to be more similar for entropic driven organization to occur.
The most amazing work of Einstein's career was the 8 or 9 years he spent developing the General Theory of Relativity. The 1905 papers were all worthy of Nobel Prizes and were greater achievements than most Nobel laureates would ever make, but his General Theory is what places him as one of the greatest of all time... comparable to Newton.
The problem was that I had planned to do the experiment in the laboratory and I forgot that there was a class there so the video was recorded with me surrounded by students, and with Prof Peter Kroger who was running the class.
I was worried that the students would ruin the video (they didn't) and was asking Brady if he had enough material for a video. That's why I asked Brady "Have I finished." Stupid of me because he was then able to leave it in.
Yes, you are right. But depends very much on the context too
Love the angry have I finished at the end!
@htomerif I have no idea, but couldn't there be larger molecules in the water being buffeted by the H2O which are in turn buffeting larger molecules etc up to the pollen?- Also i believe there are many different types and sizes of pollen- so it probably depends which type you are measuring.
What would happen if you had about 10 of the white spheres...I just wonder if they would clump together so that the motion of the little spheres is maximized. Would love to see this tested.
I have no doubt he is a great lecturer
As George Box said: All models are wrong, but some are useful.
Whether or not it is actually random, assuming it is random makes good predictions.
This is a great video and is easy to understand.
If the device was left on indefinitely would the bronze erode or the container? I was just wondering if they were getting a daily dose of bronze dust.
Is this team working on granular media physics? You guys should do another video with them, there's tons of very neat experiments to show in there!
How do you build the machine used in this video? Can you provide a blueprint? Thanks.
Can someone expand on his reference to a "Roman person", is there any famous text describing that observation of dust? or is he is just making that up?
random is just a word we use
cus its very very very hard to predict how sand particle would move in the wind for example .....so its easier to call it random.
The Roman Lucretius's scientific poem "On the Nature of Things" (c. 60 BC) has a remarkable description of Brownian motion of dust particles. He uses this as a proof of the existence of atoms:
So how do you use a sub-meson brain to generate finite improbability fields using Brownian motion?
very interesting. i would love to see more videos more often, but you cant always get what you want.
its because these position of molecules in the air are random, so when the atoms vibrate they move around the larger molecules in the air like dust in a random motion. but that's my theory
Proof of theoretical continuity because perfectly numerical discreteness would be inflexibly phase-locked, so coherence-cohesion is Reciproction-recirculation logarithmic continuous spectrum of Bose-Einsteinian QM-TIME Condensation phase-locked states of chemical bonding compositions.
I love how in the end he says that quantum mechanics disagrees with determinism
I like the bit at the end "have I finished?"
frequency's should be able to control direction on flat surface but coil from speaker used is pulsed from centre so it will eventually push it out to side no matter the frequency or or how smooth the surface is ?
another variable is !ramp effect
vibration cause larger objects to surface and smaller to sink eventually separate/sorting them into layers based weight first then mass second ,but in lowest layers are the larger mass pulled towards or pushed away from centre by the pressure above ?
I think the little device used in this video is just an analogy of what happens at atomic levels. So far I know, there is no way to predict without uncertainty the behavior of particles at that scale, so, for all useful purposes you can safely say the brownian effect is random.
so you think you could accurately predict how it will move?
where i live, most days are sunny and it only rains occasionally, does that mean the wheather is not random but instead follows a pattern?
@VanderWolls
Appeal to authority.
I'm not saying that you're wrong though. However, to me it appears like that professor Browley say that it should be possible to work it out in a deterministic manner from 5:00 onward. To me it seems like Browleys own objection against the deterministic approach is that all starting conditions can't be specified.
Is it me or the example is a bit flawed? We know the ball will tend to move towards the edge of the glass because it's contained. My guess the kinetic energy is not transferred as it should be if it were on a huge platform.
Has anyone tried this on a huge vibrating bowl, say 1km? I'd like to see what happens!
Why call it Brownian motion? Why not Brown's motion or just Brown motion?
i noticed it and discounted it as being a trick of the camera focus on raply vibrating particles...amiright?
The first time I saw that I thought it was the bronze hitting of center from underneath and that was pushing I didnt realize it was hitting it on the side.
White Fox I think your first observation was right. It looks like the vibration is in the vertical direction and most of the bronze pellets just go up/down. When they hit the polystyrene ball off center, the normal force will have a horizontal component, causing it to change horizontal motion.
@TheLensmith
Is that a riding policeman or an office officer?
I had no idea, thanks for letting me know.
Yeah, I did notice that also. This particular experiment shows the general idea and is a little far from an ideal experiment where the motion of each bead is practically the same.
@Qtyled that is the basis for quantum mechanics, right?
and how would you know when 'a thing behaves randomly' ?
we are not arguing over the symantics of the word random are we? i'm defining random as meaning unpredictable. am i mistaken? if so, why? or are you saying it means unpredictable in practice but in theory would be predictable if you could analyze ALL the data?
I like how they used an old sub woofer to build the machine.
Does every object have random forces acting on it at all times?
@bugilt there are as many good solutions to random number generation in computers as there are needs for the randomness of said number. From NSA approved nuclear decay to the parametric clock based randomness that's good for everyday uses.
we need slow mo guys here
+Akbar Haha true!
@VanderWolls: Ha... That's what Professor Bowley should say back to me when I don't understand him and ask all sorts of uninformed questions! :)
Surely though, wouldn't it be possible to somehow scan the position and variations of each of the bronze particles in the jar and the position of the 'pollen', in an extremely well controlled environment, and then run it through a simulator in a super computer and get the same results as if you tested it?
Some things are inherently unpredictable, and at some level the accuracy of your measurements would reach a limit. IOW, even if you know the all the particulars about a system, you still can't predict the future of it.
It is not impossible to measure, but we simply do not want to take our time to measure. Some people spend money without thinking and when they look at the bottom line, they think that what lead to it was random. What I am trying to say is thar the threshold where we give up counting and accept “randomness” seems to be arbitrary.
so if we can not predict something, are we allowed to say that it's random?
It would be much appreciated if you put some equations
he loves that frequency oscillator. Hell /I/ love that oscillator.
To be honest, with a beyond-exascale computer, you could probably model it with a fair degree of accuracy. Would be interesting to see what results it actually threw out taking into consideration quantum mechanical effects.
The granularity of brownian motion would seem to suggest that it's possible to reverse entropy. To take out all the energy from thermal movement. Am I wrong?
+Dan Frederiksen You're wrong, but I don't know why
+Dan Frederiksen Interesting!After a bit of googling around it seems that ALL equations in current physics models are reversible in time, EXCEPT for some instances of the second law of thermodynamics... I don't fully understand it (or have time to research) but here is a little wiki link if you'd like to do more research on the matter
en.wikipedia.org/wiki/Irreversible_process
+Emily Jayne Peters, I figure that thermodynamics is a second rate macroscopic physics and not really fundamental.
I think of entropy as a result of the arrow of time only moving in one direction. If you could reverse time you could reverse the increase in entropy over time. Would that happen if you chilled some particles to absolute zero?
+jack smith If you reduced anything to absolute zero you would break physics. Absolute zero is apparently impossible to achieve.
Diffusion constant? please elaborate!
Douglas Adams seemed to be fascinated by the idea of Brownian motion...
2:57 What did he mean? Braidy, did your mind wander?
no, there is chaos too. chaos doesnt mean that we dont know all the variables. chaotic movement has literal chaos in it. what you said is true for classical physics.
Is there a difference between "random" force/event and "unpredictable" force/event?
to me there is no difference between the two
Did anyone else notice that about half of the bronze beads in the container move a lot less than the other half? And that the styrofoam ball tend to go to where there is the most movement? It somehow seems a little bit less random to me! Could someone please explain this? (or an idea for a future video, Brady @sixtysymbols ),
Cheer's, Ole
I'm confused. I threw some math at it to see what stuck, and using 3000 grains per mg for pollen, you end up with a pollen grain being 1.1*10^16 more massive than a molecule of water. Wouldn't a single molecule of water "banging" into a pollen grain have to have an enormous velocity to make it move visibly even under a microscope? I mean, I guess not, but its still hard to understand.
"Have I finished?" LOL.
Was Robert Brown allergic to pollen by any chance?
@gomunkul
You are quite right.
The thing is, science requires emprical evidence, you can't just get it all from your own head. The prof here has spent his career studying the topic matter, and would have seen an extream amount of experimental data, and spent years studying relevent calculations.
I just think people should first ask him: "What makes you say that?", and when he explains his reasoning, then consider whether you agree with his conclusions.
I don't think we should follow blindly.
Have I finished?
Could this help random number generation in computers?
lol at the ending, great video
@systematic101 Thats what you would think, but this would imply some kind of larger order coordinated movement of molecules than simply on the single molecule level, even if the coordination is only for brief times and on microscopic levels. I would actually have a few questions about that to ask a physicist well versed in that subject, though I don't know any.