Modern technology has made the operation of wheeled vehicles so easy that many people tend to take the vehicle for granted. Actually, all vehicles can be broken down into several systems, each performing a separate task, yet complimenting each other to make the vehicle perform smoothly. If all the systems in a vehicle were listed in their order of importance, the brake system would have to be one of the systems near the top of the list. As a wheeled vehicle mechanic, it is important to remember that the quality of any brake service is always measured in terms of safety. To effectively troubleshoot and perform brake system maintenance, it is essential to have an understanding of basic hydraulic principles. The engine will get a wheeled vehicle rolling, but it takes brakes to stop it. In today's Army, hydraulic brake systems are common, and among those the ones you're likely to see most often are the drum brake systems used on M151s, the 1.25 tonne 4x4 utility vehicle the Army has so many of. But there's also another type you need to know about. The M880 1.25 tonne cargo truck uses drum brakes in the rear, but up front it has a disc brake system. As a wheeled vehicle mechanic, you've got a lot of personal interest in making sure those brakes are working, because the vehicle whose brakes you maintain or repair, you've got to road test. It's up to you to put safe brake system operation at the top of your list anytime you work on hydraulic brakes of any kind. The safe operation of a vehicle and somebody's neck, even your own, could be at stake. For that reason we'll concentrate on what you need to know about hydraulic brake systems, what they look like and how they operate to help you maintain, troubleshoot and repair them efficiently and safely. When you have viewed this program, you should be able to understand the basic principles of hydraulic brake systems. You should be able to identify the components of the drum brake system used in the M151 and understand its principles of operation. You should also be able to identify the components of a disc brake system like that used in the M880 and understand its principles of operation. In part one of this program, we'll discuss basic principles of hydraulic brake systems that apply to both types of brakes, and then discuss the drum brake system used on the M151 vehicle. Part two will cover the disc brake system used on the M880 series vehicle. Get a good grip on the basic principles and you'll be in good shape to maintain brakes or troubleshoot and repair any hydraulic brake system you're working on. First let's look at basic principles of hydraulic systems because these control everything that happens in hydraulic brake systems. Under normal pressures, liquid cannot be compressed. This heavy weight, for example, cannot press the liquid down beyond its original level. It is, however, putting force on the liquid. This force acts in all directions, putting pressure on the weight itself and on the walls and floor of the container. The pressure is the same at all points. Another thing about liquid is that it occupies the entire volume of the container, filling every space no matter what its shape. This mock-up has a weight in each cylinder and we'll call these pistons like those you'd find in a hydraulic brake system. Let's watch what happens if we push down on one of the pistons, putting extra force on the liquid. The liquid is non-compressible, so its volume remains the same. The effect is to transfer the force to the second cylinder where it acts on all surfaces, but only the piston is free to move and so it rises. Now we can see another important principle of hydraulics. The area of each piston is the same, so the right-hand piston rises by as much as the left-hand piston is pushed down. That's because the pressure is the same on the face of both pistons. Let's see what happens if one piston is bigger than the other. The small piston puts a certain amount of force on the liquid. At the larger piston, this same force acts on each area that's the same size as the small piston, so the pressure on the face of the large piston is multiplied by that amount. This means the force applied by one piston can be multiplied many times just by enlarging the area of other pistons in the system. One other thing happens. The smaller piston has to travel farther to raise the larger piston by the same amount as before. The same things happen if instead of one large piston, there are several whose total area is larger than that of the piston applying the force. Once again, the liquid can't be compressed, and its volume remains the same as force is applied, so the force is transferred to each piston in the system simultaneously. This is like the situation in a hydraulic brake system. The cylinder with the piston that applies the force as the lever is moved is like the master brake cylinder. The connecting pipes are like the brake lines. And the four cylinders with pistons are like the wheel cylinders, except that in each M151 wheel cylinder, there are two pistons, not just one. Keeping the principles we've just talked about firmly in mind, let's look at each of those components as they appear in the M151 drum brake system. Let's start by looking at the master brake cylinder. It's hard to see because of the way it's installed, so let's look inside the vehicle. The master brake cylinder is the heart of the hydraulic brake system. The brake pedal moves a piston inside the cylinder by means of this push rod.  Brake fluid also fills the brake lines through this outlet. They connect the master cylinder to the wheel cylinders at each wheel assembly. For a closer look at a wheel cylinder, let's go right into the brake assembly with the wheel and brake drum removed. In the M151, the wheel cylinder is located near the top of the brake assembly. Pistons inside the wheel cylinder bear against the studs of two brake shoes. These brake shoes are retained by springs, so they are fully floating and self-centering. The base of the shoes engage an adjusting screw, often called a star wheel, and are coupled to it by a return spring that also helps pull the shoes away from contact with the drum. Other ends of the shoes fit against a hold down anchor pin at the top of the brake assembly. The brake shoes are surfaced with linings that will wear down as the brakes are used. The brake drum mounts over the brake shoes, which apply pressure to the inner surface to stop wheel rotation. Now, we'll concentrate on the principles of operation of a service brake system using drum brakes like that in the M151. In this system, the brake pedal is a lever that multiplies the amount of force applied by the operator by mechanical means. But that force is multiplied further by the hydraulic system. So first, let's look at the active hydraulic components. The master cylinder and wheel cylinders to see how that happens. Then let's see how all parts operate as a system to make the drum brakes work. The master cylinder has two basic sections. One is a storage area called a reservoir for the fluid. The other section is a cylinder which contains a spool shaped piston. Small holes are drilled through one rim of this piston. The cylinder also contains two sealing cups, a return spring, and an outlet check valve called a residual pressure valve with its own spring. A push rod transfers brake pedal action to the piston. The reservoir contains a supply of brake fluid. It's important to leave some space above the brake fluid to allow for expansion. Brake fluid must not be allowed to drain out of the reservoir completely because this will let air into the brake lines and we'll see what effect that has later. Your manual will tell you what the proper level is, keep it there at all times and you won't get yourself or the users of the vehicle in trouble. One thing more about brake fluid, it absorbs water which could cause serious problems throughout the brake system, so keep the reservoir tightly covered at all times. The two ports in the base of the reservoir provide pathways for brake fluid movement. The filler port is larger and supplies brake fluid to the system. The compensating port is smaller and allows passage of expanding or contracting fluid. Fluid movement is controlled by the action of the piston and two cups which both point forward. As the push rod transmits pedal motion, the spring applies force against the residual pressure valve, while at the same time the piston cup closes the compensating port. This primary cup faces forward and as piston motion continues, it seals in the pressure that now starts building up in the outlet end of the cylinder. This fluid pressure unseats the residual pressure valve, opening the way for the brake fluid to pressurize the brake lines and wheel cylinders. And look at what happens there in a moment. For now, let's follow the action in the cylinder when the brake pedal is released. The spring drives the piston and sealing cup backward and so pressure forward of it and in the brake line drops. This brake line pressure bears against the residual pressure valve, tending to hold it open. But eventually, as brake line pressure decreases, the spring overcomes its force and reseats the residual pressure valve. This traps a small amount of pressure in the brake lines and wheel cylinders and we'll see the effects of that later. As piston motion continues, the compensating port is reopened. Brake fluid flows back into the reservoir through this path. Also the return spring pushes the piston back faster than fluid can return. This drops the pressure ahead of the cup so it is now free to flex and unseal the holes in the rim of the piston. Fluid can now return to the outlet end by this path, ensuring that this space will be completely filled for the next braking action. The spring drives the piston back against its stop to complete the braking cycle. Because the secondary cup at this end of the cylinder also faces forward, no brake fluid can leak out of the system. Now let's get into the other active hydraulic component, the wheel cylinder, and see how that operates. This device is connected to the steel brake lines by a flexible tube that allows for turning and up and down movement of the wheel. Inside are two pistons that bear on the brake shoes, a spring that positions sealing cups against the pistons, and a bleed air valve that lets you get rid of air in the brake system, as we're showing you here on another wheel cylinder. The combined area of the wheel cylinder pistons is larger than that of the master cylinder piston. So the force that the master cylinder piston applies is multiplied several times, adding to the force provided by brake pedal leverage. As the piston in the master cylinder puts pressure on the brake fluid, this forces the wheel cylinder pistons to move the brake shoes apart. We've exaggerated the action here so you can see what happens. Brake shoe springs return the pistons to their stops as brake pedal pressure is released. The piston cups face inward, and so prevent brake fluid from leaking out. Now we're ready to look at the entire drum brake system and see how it operates. You can control the amount of braking power the hydraulic system will deliver, all the way from slowing down wheel roll to wheel lock by the amount of pressure you put on the brake pedal. Here's how it works. Remember that the brake pedal acts on the master cylinder piston the same way the lever acted on the piston in our hydraulic system demonstration a while back. The brake fluid is not compressible, so the further the lever pushes the piston, the further the fluid pushes the second piston. The same thing happens in the drum brake system. The result is that as pressure on the brake pedal increases, so does the pressure exerted on the brake shoes by the wheel cylinder pistons. Let's look at the situation using just one drum brake assembly, remembering that the same things happen at the same time at each wheel. This area is the braking surface of the drum. Actually the gap between brake shoe linings and the brake drum is very small, but we're making it larger here so you can see what's going on. Let's say the wheel and the brake drum assembly attached to it is rotating. Now let's push down on the brake pedal. The master cylinder piston transmits force to the brake fluid in the brake line and in the wheel cylinder. Both pistons are forced outward against the brake shoes and these in turn are forced into contact with the brake drum. The friction between the brake shoe lining and brake drum begins to slow the wheel down slightly. Now let's push down harder on the brake pedal. Because the brake fluid can't be compressed, it transmits this increased force against the wheel cylinder pistons, increasing the pressure against them. The wheel cylinder pistons push harder against the brake shoes. The brake linings harder against the drum, slowing the wheel even more.  Releasing the brake pedal lets the return springs pull the brake shoes back from contact with the drum and drive the pistons back to their stops in the wheel cylinder. The master cylinder piston driven back to its stop allows pressure in the system to decrease, but the residual pressure valve closes, keeping just enough pressure in the brake line and wheel cylinder to keep its sealing cups pressed against the pistons. These face inward so no brake fluid can escape from the system. If there is a lot of repeated braking action, the friction between brake shoe linings and drums will generate excessive heat. This heat can also heat up the brake fluid in the wheel cylinder, causing it to expand back up the brake lines to the master cylinder where it later returns to the reservoir through the compensating port. Now let's say some air is trapped in the brake line near a wheel cylinder like this. Air is compressible and that can cause problems. Let's again push down on the brake pedal until the brake linings make first contact with the brake drum. So far so good. But now let's push down harder. Here's where the problem shows up. The increased pressure in the brake fluid presses against the air bubble and it shrinks. Let's say the air bubble gets forced into the wheel cylinder. Plainly the full force generated by the master cylinder piston is not being transmitted to the wheel cylinder pistons and brake pedal action feels spongy. It takes a lot more pedal pressure to bring the wheel to a full stop and the air can cause uneven vehicle braking. That's why it's so important to follow directions in the manual for bleeding air from hydraulic brake systems anytime you work on them. There's something else going on in a drum brake system you need to know about if you're going to really understand how this system operates overall. When drum brakes are applied both shoes initially contact the drum with equal pressure. This is the reason why the space on each side of the anchor pin is equal. However friction between the rotating drum and shoes tends to pull the shoes around with the drum. When this happens one shoe is forced farther away from the anchor pin. This in turn forces the other shoe tightly against the anchor pin. Increased friction at this point tends to make both shoe assemblies pivot using the anchor pin as an axis. If the drum were not present to contain the shoes the action would look like this. Since the drum is present the shoes are forced into tighter and tighter contact with the drum. This is what is meant by the term self-energizing in reference to brake systems. This action thus multiplies the force of the brake shoes on the brake drum. One more thing you need to know about drum brake operation. You'll remember we said brake linings will wear with use. The brake pedal then has to travel farther to force the brake lining to make contact with the drum. To close this gap to normal you'll be using an adjustment tool to rotate the star wheel on the adjustment screw. This will return brake pedal travel to normal. Excessively worn brake linings will of course have to be replaced so the shoe doesn't score the drum surface. The components and principles of operation for the drum brake system on the M151 are similar to others you might come across. And also to the drum brakes used on the rear of the M880. In part one of this program we've reviewed the basic principles of hydraulic systems. The fact that liquid is not compressible and occupies the entire volume of its container. The fact that force applied acts in all directions. And the fact that force applied by one piston is multiplied by the areas of the others. We then reviewed the major components of a drum brake system. Master cylinder, wheel cylinders, drum brake assemblies. And talked about the principles of operation of components individually and as a system. If any of this got past you the first time around don't feel bad but give it another shot. Look at the program again as often as necessary to get a handle on it. In part two we'll concentrate on the major components and principles of operation of the disc brake system used in the M880 vehicle.


Now we talked about scalar multiplication of two vectors but to do proper arithmetic and proper algebra with any sort of mathematical construct what we need to be able to do is to define how the objects operate with themselves. So if I have two vectors I can find what's called the dot product of the two vectors and that emerges as follows. So what I'm going to do is I'm going to take my two vectors v being the set of components and w being the set of components. I'm going to define the dot product to be this product v1 times w1 plus v2 times w2 and so on. I'm going to add together the component wise product of the two vectors. Now this also is known as the scalar product and the reason it's known as the scalar product is that this thing that we end up with here is not actually a vector. It's a real number if our vector components are real numbers. So we end up with a scalar not a vector. We also sometimes call the dot product the inner product. And so for example let's take two vectors in R4 and find the dot product and I'm just going to multiply the corresponding components. So v dot w is going to be the dot product of the two vectors and I'm going to multiply them component wise. So that's 3 times 2, 5 times negative 1, 1 times negative 5, 8 times negative 1. I'm going to find all those products and I'm going to then add them and there's my dot product. Now why would you want to do this? Well there's some useful properties of the dot product that make it very important. So one of the useful properties is that it's commutative v dot w is the same thing as w dot v. And this emerges directly from the definition of the dot product. It's something you should be able to prove without any difficulty. Another useful connection to make is that if I take the dot product of a vector with itself, what I get is the square of the magnitude of the vector. And this follows just from the definition of how we find the magnitude of the vector. Probably the most important property of the dot product is the following. If I find the dot product of two vectors, what I get is a product of the magnitude of the two vectors times cosine of theta, the angle between those two vectors. And this gives me quite a bit of insight into how those two vectors are related to each other. Let's see how we can make use of that. For example, let's consider two vectors this time in three dimensional space. We'll take a look at the angle between the vectors 3, 2, 5, and 4, negative 1, negative 6. So what I have is I can find the dot product first. And again, that's going to be the component-wise product added together. So that's 3 times 4, 2 times negative 1, 5 times negative 6. I multiply those components together and add them. I get negative 20 as my dot product. And what I have is that that dot product is the product of the magnitude of the two vectors times the cosine of the angle between them. And so I can find the magnitudes of each vector. So again, that's going to be the square root of the sum of the squares of the components. So this vector v has magnitude square root 3 squared plus 2 squared plus 5 squared. And this vector w has magnitude 4 squared plus negative 1 squared plus negative 6 squared. And I'll take the square root. And after all the dust settles, I end up with the cosine of the angle between them is negative 20 over square root 38 times square root 53, which tells me that the angle between them is the arc cosine of some expression. And I can find this numerically. This is about 2.037 radians. Remember, after calculus, degrees don't exist. You should be speaking entirely in terms of radians. But since it's a little harder for us to get some insight into that, we're more familiar with degrees that work out to be about 116 degrees. Well, here's a very useful idea. If I have two vectors, I call them orthogonal, if the angle between them is plus or minus pi over 2. And in this case, if I have two orthogonal vectors, well, let's consider what happens to the dot product. If that angle is plus or minus pi over 2, then the cosine of that angle is going to be 0, and that's going to tell us that the dot product is 0. Now, we also have one other consequence of this. This also works backwards. If the dot product of two vectors is 0, then the two vectors are also orthogonal. One minor qualifier here, we have to make sure that neither vector is actually the zero vector. So we can do this as a quick check to see if two vectors are in fact orthogonal. So for example, I have three vectors, u, 1, 2, 5, v, 5, negative 4, 1, w, 3, 1, negative 1, and let's see if these vectors are orthogonal. So I'll find the dot product of each pair, u, dot, v. I'll multiply the components and add, and that gets me negative 2. It's not zero, so these two vectors are not orthogonal. The next pair, u, dot, w, I'm going to multiply the components together and add, and I do get zero, which tells me that u and w are orthogonal. And then finally, that last pair of vectors, v and w, I find the dot product, and after all the dust settles, I get something that's equal to 10. And the only one whose dot product is equal to zero are the two vectors, u and w. So only the vectors u and w are orthogonal.


At the Prophet Yusuf, he was young and he had many older brothers and he was the son of a Prophet, the son of the Prophet Yaqub. Jacob, known also when we hear Bani Israel, he is known, he is Israel. Bani Israel stems from him, very, very important Prophet in our tradition.  And so early on in Yusuf, like his brothers were jealous of him. They were jealous. And their jealousy, they were like, why does why does my father give so much more attention to Yusuf, that's what they felt, right? These were their feelings. And so what did they, what do they end up doing? They end up plotting to find a way to harm their brother. And then some of them get to the point where they say, you know what?  Because we're so jealous of him that why does he even have to exist? And so they begin this process of trying to convince their dad, their father, Yaqub, let Yusuf come with us. Let him come with us. We want to go outside. We want to play. Let him come with us. And Yaqub, originally he's hesitant. No, no, no, no. But then he sends Yusuf as they take him. And many people know this story. And as they take Yusuf they originally make it seem like they're going to just all hang out as a family. And then they are about to kill him until one of them suggests, no, no, no, no. They see a well. They say, no, throw him down that well. He's not, I mean, he's as good as dead, right? Throw him down that well.  So they take their own brother, their own brother and they throw him down a well.  You're in a very, very dark and difficult place.  Now Yusuf lives a life of a lot of difficulty.  Of course, Allah had something different written for him. People who are on their way to that well and they're on a journey route. They stop at the well and they come to get water and then they see a boy come up and they get excited and he's then sold into slavery. They take him and they sell him into slavery. He lives a life of difficulty and of tests because of the jealousy that his brothers had for him. A lot of hurt is now coming through this process for Yusuf. He then is wrong again by a whole community. The house that he's in, the wife of the master of that house, she tries to seduce him and eventually gets him thrown in jail because he wouldn't succumb. Because he was a proper person of nobility. He didn't do anything wrong. He gets thrown into jail. Now he spends a period of his life in jail, in prison. Again, an immense difficulty. A lot of hurt getting come, a lot of hurt happening inside Sayyidina Yusuf But what ends up happening is that at some point he gets out of that situation and through the way that Allah works, Allah ennobles him and honors him and he is given the position, essentially if you could consider the economic minister of Egypt at a very, very high position in the government because of the abilities that he had. And so now Egypt at this point enters into a famine and Yusuf has come up with the plan to store food and he is responsible for distributing food to all of the people in the lands from far, far away that will come to get that food. And so at some point, who does he see? Many decades later, come to get food. He sees a caravan of which his brothers are a part of that caravan. These are the brothers that hurt him.  These are the brothers that through their jealousy, literally threw him down a well and left him in the wild. And so he sees them come and he comes up with a plan that they come the first time. They have no idea that it's him. Of course, he's grown up. They would have no idea. But then eventually he sends them back and they come a second time to get more food. And he asks them this question. Now he wants to show them that he knows. He asked them, do you know what you did to Yusuf when you were in the state of Jahlia, when you were ignorant? And they say, are you Yusuf? He says, I am Yusuf. Yes, I am Yusuf. And now remorse overcomes his brothers. Of course, I mean, how could you even live with that? I'm sure for many, many, many years after that, that taunted them, how could we do this to our little brother out of jealousy? But they did it. They did it. And now remorse comes to them. And what do they do? They ask for an apology. Forgive us. We're sorry. We were, we were, yes, we were wrong. We're sorry. And what does this noble Yusuf, Allah, do that? What does he do? He doesn't have to forgive them.  Somebody tried to throw you down. They threw you down a well they left you. I mean, you don't have to forgive them. He could just say, you know, we'll talk about it on the day of judgment. But I don't have to forgive you though. What does he do? He says, there is no blame upon you this day. Nothing. Allah is all forgiving. Allah is all merciful. And he pardons them completely. And he pardons them completely. What manifest character he had. And we have to think when we wrong people, if we're the ones who do the wrong, do we ever get the courage to go and apologize? And if we are the ones who are doing, who are, who are being wrong, do we have the magnanimity and the expansiveness of heart to follow the sunnah of Yusuf and also the sunnah of the messengers to have a heart that is full of mercy and full of forgiveness.


Andy Ogletree has already won the international series order of merit but after a 74 yesterday it looked like missing the cut for the first time this season. To the Americans great credit though he came back with 31 on the back nine today a 65 and made the cut at three under par. Terrific effort by Andy Ogletree. Graham McDowell another who made the cut at three under a birdie putt at the fourth from the former US open champion a 68 today and another man who made a great comeback was Ben Campbell last week's Hong Kong open champion two over yesterday but six under today four under for 36 holes. Pumsak Sanshin was as consistent as ever. This is his second into the third. Beautifully played he would hold the putt and he's inside the top ten. So too is his fellow Tai Gun Charonco. This is third into the difficult par five closing hole. He would shoot 68 for seven under par. Now Patrick Reed the former masters champion making his first visit to Indonesia. He's obviously enjoying himself. Played well today. He's an eight under after a 68 and very much in contention for the title. He's lying third. Won ahead of him in second place Richard T Lee of Canada. Didn't quite make birdie at four but a 67 for nine under. The man they've got to catch is Gaganjeet Bula bit of an Indonesian specialist. He's won four times in this country three of them in the Indonesian open. That was at the fourth. This at the 18th no birdie but a par good enough for a 67 and at 12 under Gaganjeet Bula leads by three.


Orientation is locked. I want it this way one second. Hang on folks. We're live. Just give me a half second Why is it locked? Oh? Good discussions. Let's see. Hey, we're live just Hang on a sec looking at the backside here of the Pantheon to You're going by I will try it Hey, let's do it. We'll do it. We'll do verticals give it a shot because all the youngsters like vertical. Hi, Amelia Amelia should be studying. Okay, everybody.  In Rome and this is a nice quiet moment to be here People are going by we'll see in their bicycles I want to have you look down here for a second and we're gonna see a couple ancient things We're looking down into the pavement level Contemporary with the Emperor Hadrian and this is Come on this way. We're gonna go this way and walk into the so-called the silica of Neptune So it doesn't look very big because the bulk of the huge haul is not excavated but what we do have is an apps so an Apps if you're not familiar with this architectural construction is this recess sure you see it in churches But it all comes from the Greeks in particular the Romans and you see down below here Can you see that big square base? It was once lined with marble the whole Recess was lined with marble. This is for a colt statue. So if it's the basilica of Neptune Then you're honoring the god Neptune we know that there is such a structure in the time of a Grippa the right-hand man of Augustus He builds a stowa or a basilica According to the Greek source. This is the Hadrianic version of This structure. So we're literally just south of the pantheon this structure abuts the pantheon and Behind the south You'd make your way all the way to large Argentina with the four temples and a pit We have a great video on that on the reopening on ancient Rome live but in between the basilica this courthouse the basilica of Neptune and the pantheon and All the way to log Argentina in between is the baths of a grippa So a grippa built a lot for Augustus Augustus, of course ends the civil wars against Mark Antony and Cleopatra and he builds a lot in the city and He has his right-hand man and his great general a grippa build things as well so a grippa is going to be responsible for a lot of things in this big flood plain this flood plain is the campus marshes dedicated to the god of war He is credited he a grippa is credited with building the first pantheon the basilica of Neptune the baths he brings the aqua viergo that still fills the Trevi fountain and then of course he's going to build a stagnum a pool for swimming and Yeah, so man, I think you guys can hear me. Okay. Feel free to type in your questions or leave comments That's a beautiful day and We do get some We erected columns here. We do get some of the Entablature up at the top here Remember keep in mind that we are inside the basilica. We're not in the exterior of a building We're in the interior of a building that goes back the time of Hadrian now Let's pivot up for a second and we can see we're right that curve right there That's the pantheon. So we're not starting with our typical kind of you the pantheon We're starting with a little different view and it's just a reminder that the campus marshes was extremely crowded with all kinds of buildings And this is just one of so many buildings preserved in Rome that has Just a fraction of its entirety preserved invisible to us What's that? Oh my hand So I never I've ridden a scooter for many many many many many years and I never get hurt and I hurt my thumb So that's it. It's nobody gets a little sprain. I Still can do workouts, but I have to do it on my fists. I cannot do a normal push-up just yet So I have to be careful, but everything's cool. Thanks for asking Let's go over and we're gonna get a side view of the pantheon. So we'll come over the pantheon today We've done walks like this before You can check out all the great new content on ancient Rome live I'm gonna tell you that we always need your support a lot of you are very generous and we appreciate that We want everyone the average viewer if you're not involved in the organization Please get involved because we do extraordinary things. We can do this every night. I'm gonna do this every day So you're gonna see a lot more live stream. So it's just ancient Rome live.org slash support We're gonna have some online classes again, and we're gonna have a number of On location courses this year such as the Suvian cities City of Rome and so on. Yes Well, we're gonna be heading over to that's in the front of the pantheon the answer is no it has been excavated in sections I Need to devote a little video to that one segment that was revealed there was basically a part of the pavement Collapsed and an excavation then was done and during Kobe They revealed part of the pavement which is probably almost definitely dating to the time of the Hadrianic pantheon not the one of Agrippa and They subsequently covered it up, but They've done that another time So we know that the entire piazza was papers of Travertine stone in the time of Hadrian what it was in the time of Agrippa is another question Sorry, what year was it built? Pantheon was built the last time let's go back in time the panthen was built in the 20s BC by Agrippa same scale It burns down in the fire of 80 AD we talk about that in our larva Argentina video on the four temples in larva Argentina So there's a huge fire in the reign of Titus so Demission subsequently he succeeds his brother. He builds another pantheon and that burns down in a fire in 110 So the new up-to-date scholarship assessment is They're getting done with the form of Trajan 110 112 and The fire had taken place here in 110 So looking at brick stamps and so on the new assessment is that they start to build the final version of the pantheon in 114 who's the emperor Trajan he dies in 117 so it's going to be completed in about 125 by Hadrian So that's why we go around saying it's a hedronic pantheon But probably that ultimate awesome design was by our buddy Apollodorus of Damascus who's the Architect under Trajan we're going to come over here. I'm going to show you something else Great question. Yeah, let's turn around here for a second and show this little narrow street So your average Roman street is Two carts can pass. So this is like your average Roman street a little bit wider about 16 feet. So That's your average Roman street now In America in New York. I like to talk about Broad Street Okay, so you had the Villalata, which is Broad Street. That's the Villa though, Portugal the north south row that runs from the Vittoriano Monument to Cazado Popola And it was a very wide street by Roman standards probably twice as wide as a normal street There's also a Villalata a wide street or a Broad Street in Syracusa, which is a major Greek city in in in Sicily And I was just reading about another one the other day Anyways, so there are a number of Broad Streets and antiquity, but the most famous one of Rome was the Villa though course So let's come over and look at this structure right here Are there any instructions here by? Of course, what kind of description? There's like thousands of inscriptions That's it. That's a great question. I need to know what kind of description you want But can you see this wall right here? See how that looks.  So that's the outer wall of one of two covered walkways for the site to do the site to Julia the site there was a Let me tell you what that is. It's a voting enclosure. So Where do you go to vote, you know, you go to your local way It's the school the local school district and you go and vote in the states Here same thing we use their children schools to go and vote So what are the Romans do and voting was right here It's the main place to vote. So imagine a An enclosure That's what it was known at the enclosure the sheepfold for all the sheep to vote.  So they do eventually Institute of the Private so what you did was there's an isolated area where you're given your little test of that Which you'll mark when you're voting and then you deposit it in an urn and then it's counted in another structure called the Toria actually had a there's a pretty decent System and you have that more what you weren't behind a screen or anything like we do today to vote in privacy But you went up on a on a little bridge. So on the bridge you have that moment of Isolation, okay, so then imagine I'm talking about an area That's approximately three and a half football fields long and one football field wide So it's a huge area. You're enclosing it with walls. This is one of the walls now This is a wall though. That's built in the time of after the fire of 110 So it's attributed to Trajan and the Hadrian now, of course the Romans, you know, they don't like rain So they always want to have a place to be covered. So that wall Had in front of it a row of columns 300 meters long on both sides. So imagine a very large covered hall where it ultimately because of the The grandeur of the city and the wealth of the emperors it gets filled with artwork So one is named after the Argonauts Referring to the art probably a painting and the other one is of Melieger who hunts a wild boar There's more information that you want to know guys, but essentially You know, you have Republican times going back to 435 BC and you build it again and again and again remember It's from fire destruction and and flood damage. So the last big one was built by Augustus with with the Agrippa and it's called the Cypher Julia So they now add the family name of Julia Caesar So Cypher Julia and then you haven't rebuilt after the fire of 110 And that's the remains of which we're looking at right here. This one little piece of law So that also gives you an idea now How proud of the urban space was in the campus marshes that the voting enclosure here You've got the basilica Neptune there and then we're gonna wind our way to the front with the pantheon So just and just be honest to the east. There's a temple of Isis and so on. So this is a really crowded area Okay, great question. So if I walk Do south from here? 300 meters and cross streets. I'm in Largo Argentina and in Largo Argentina there are four Republican temples and budding up against behind Temple B. This is all in our amazing video on the reopening of our garden Tina, then you'll get it and you'll see a Wall that belongs to a space that was used by the Senate with Julia Caesar was assassinated Why was any killed in the Senate House in the form well and had burnt down in riots So it was in the process of being reconstructed Otherwise it would have been killed there So it's a it's a funny thing when you read your history books and you're told he's killed in the Senate House But then it's not in the form when the Senate House is they use another Senate House and that was in the complex built by that great general Pompey the Great So let's go. Yeah Okay, so what we'll do is I'm cool Yeah, what's the bad connection? We'll just keep on going if you're if you if you have any problems connections Dial out and dial back in as it were we're gonna go to the front of the pantheon and Then I want to remind you that What what makes ancient Rome live so special obviously is we have the the knowledge that we want to share with you We have 300 plus videos that we're sharing with you. We have a website. We have experience We've excavated for 14 years and done study programs and we're very excited to share all this material but We're also doing a lot of lives now And yeah, so if you're tuning in for the first time, we want you to subscribe and You won't be disappointed and this is like a little teaser tester for us But in the future, what we doing during the day? So if you even if you miss it, I'd say that the quality will be better at the light will be better and so forth But don't forget to hit the like button to subscribe if you're joining us for the first time We're we're cracking what maybe 42,000 real soon, which is great The entire okay, so let's take a look. I mean the lights not great for this one But here's the deal. Let's come over here to the rotunda a second as we walk over here. I will tell you that yes in recent studies We're we're feel much more confident that the bulk of the exterior is covered in marble at least the lower portion And that is from the original brick surface. So most the brick surface when we look at the exterior It's not it's not original. It's not modern when you see here's a little fun fact It was not even a secret, but here's the here's the thing to do We need this ancient monuments Can you see all the chip brick right there to see how the brick has a has a has a three-dimensional kind of surface to it It's purposely been chipped. It's what they were doing since the early 1900s to tell you the viewer That that's not a real that's not an ancient brick. So it doesn't mean that the Pantheon's fake. It just means people how Some bricks fall out as the mortar weekends, but a lot of times people are robbing out bricks to recycle them You know how like today you say wow I would really like to have brick around my fireplace So they go to some tear-down building and rip out the bricks and recycle them because bricks today are expensive Same thing is going on here throughout post-antiquity the late antiquity and Middle Ages. So when you do And you do you see? Yeah, yeah, this is this is Rome Not a good idea. Anyways, when you do see more of the original surface I'm looking at a little segment right here. There are the telltale signs of some of the holes The metal pins that would have been placed with a metal where the holes are for holding in the marble venue So that's that's kind of it. There's a there's a recent article in the jerry if you want some good Scholarship one of the best You know magazines to describe to it's kind of pricey I mean it's it's two volumes as meaty comes out once a year and promise us close to 100 bucks It's kind of expensive, but go to your library what not it's a journal moment archaeology And that's not taken over by Cambridge Press Cambridge Press, but it's good and there was a recent article Exactly this so just goes to show you that you know even daily There's some student there's some scholar someone doing research asking the questions that you're asking And then trying to find out those answers and that's what makes Learning what answer room really exciting because we're always getting more knowledge And we're always getting people with other ways of looking at things to come up new Solutions to problems. How did they do this? Why is this still here? So let's just go This is these are these are short if you don't know us we do two free Lectures a month we do a master class and you can pay for that that supports us And then we were we're big on Twitter and Instagram and Facebook and so forth So you can come and find us all and at save or sorry at Ancient room live and then me personally. I'm Daria. Sorry as you can see all my stuff on all those handles Let's just go to the front we'll get the good stuff and the good stuff is the front and We're leaving the rotunda Think about the base walls the thickness of the base walls of the of the rotunda It's five meters thick think about that five meters is massive and it's gonna it's gonna Be reduced as you go up to the top But you gotta think about that rotunda as a big honeycomb you guys know what honeycombs are like So you have structural integrity you have a series of a network of walls But there are tons of voids So looking at something like this and don't think it's as simplistic as Solid mask going all the way to top holding up at 5,000 ton dome rather Just like the later domes of Brunelleschi and so on in Michelangelo. It's all with voids. It's all with hollow points We leave the rotunda We have the transition block. This is the transition block right here where there are staircases that take you up And in the future, I will take you up I've been up I will take you up in the future and then in the front porch the Pronounce where the columns are the other pronouns And you have these columns that weigh 50 tons a pop. So let's just You know take a little walk over here and We'll kind of finish up with the columns It's a pretty night as you can listen Still a lot of tourists here. Look at all these tourists with the heck What are you gonna do, but this is what you get when you get live, right? You get a lot of people It still feels like summer. We're still in the 90s And it's a beautiful night and everyone's out and then what then we'll go then we'll just go over to the Colony, which is good. Take a look at this beautiful view. That's what that gorgeous view The pantheon and of course, we're not going inside, but we can go now with the converse. Let's go in the calm Come with me So if you don't know me, I'm just gonna finish up My name is Darry. Sorry.  We're gonna give YouTube live streaming a try. I You can see me on one green traveling the Roman Empire What's that? Yeah, we'll get there. We'll get there. So, you know, I've done a lot of archaeology I've done a lot of teaching that we have a great organization where we're I think producing a lot of great content So we're hoping to subscribe the stairs are right here. You don't see them, but there are eight stairs That leads you up. So we're in a flood plain People say how is it possible that things like this? You know can get buried one this case here doesn't get buried But look behind you and you see the modern street curves down here So when you something remains in use you just make it work and you tend to do stuff like this Anyways, the ground level is substantially lower than where we are today Just go look at dark Argentina couples in the pit and so forth look down at the Roman form and so on Part of it is man-made intervention like hey our drains are now clogged Let's go up and let's put another series of drains, you know And so the things get buried in that way and another way is we're in a flood plain to a lot of materials floods Centuries and centuries of Sometimes you know by annual floods, so you just it's gonna get a lot of material imagine I mean a Katrina after Katrina after Katrina if you can relate to Katrina You know depends what your age you might say what's Katrina because we're too young But if you're old enough you remember the devastation of Katrina then what do we do afterwards? We dig out New Orleans here. You don't dig it out. You simply Put another pavement up on top We literally can see that in section on various excavations. Let's just come inside here just to enjoy these these columns It's a lovely evening. Let's show them the piazza out here a lot of people out and If we Think this so what are you looking at? We're looking at abscess for colossal statuary now missing We've got in a bronze door that is definitely ancient various scholarly debates on how authentic it is to this building versus the original one We don't have to go into that but we can see The roofing system so originally it was a drop ceiling that hid this away But it wasn't hiding away rafters and wood. It was hiding away Beams of bronze they get robbed out by the Barberines by border me called the keynote and I think we did a pretty good job. We did a pretty good walk I'm gonna have fun with the live stream. We have a lot of people watching 173 people. Oh, that's that's quite nice The columns are supposed to be taller. Absolutely. These are 40 footers. It was supposed to be 50 footers Do they have any karyatas remaining? No, that's a karyatas description was applied to in the ancient sources to the Uh a grippen pantheon not this pantheon. We don't think this one had uh karyatas figures a dent From a ram on the bronze door and I was there. Yeah Things are bound bound to get damaged Uh No, there were karyatas in the pantheon I'm liking the ancient source. Why didn't it come to Dio, but it's definitely applied to the The pantheon of of the grippa. So yeah, believe it. It was they were there Oh a lot of great content a lot of great comments. Will do lies as often as possible. I appreciate that and uh I'm gonna work on next time. We'll try a course on full which will obviously change the dynamic I think it can probably help us a lot more and that we'll just add to our library On uh ancient room live. I mean heck like I said the premise of starting each room live in 2014 was we like doing lives We've been doing zooms. We've been doing more lecture kind of uh Formats and this is a little bit different But I think this is great and I appreciate everyone who's on and uh Look, there's a lot of great content. I'll tell you right now. There's a lot of great content out there And there are a lot of great people telling a lot of great things but I promise you There's nobody that's here on a daily basis That knows what we know and it can share what we share And I know I know that I know what's out there. I know The tour guides are doing with tiktok and instagram and stuff like that Which is wonderful and fast And and and and and and dynamic We're going to give you more depth We're going to give you these 15 minute walks We give you already 10 minute videos We take we're taking you around. We're taking you to jerosh. We're taking you to elgem Uh, you know, we have a lot of great content in pump pay We work with the people in pump pay We work in the day or not tonight or month We work with the man in napal's so we're going to bring you more behind the scenes Just as fun ways to learn about this incredible content because we in the field Of archaeology and classics and our history and architecture and engineering We we we know this stuff is valid and we know how excited you are about this stuff So we keep the great questions and comments happening Come and find us in rome take our online class You're going to be able to take courses with us on location And uh, we just hope you keep on tuning in and make sure you subscribe And thank you guys very much. I think this was very successful. We really appreciate your time Oh, yeah. Okay. Last thing is I'm giving two lectures in philadelphia On september 7th, and I'm giving a trip. I'm giving a lecture in boston on september 14 And that information is on our social media Uh, it's definitely on my profile. I think immediately, which is just Darius aria digs So please come and find me in philadelphia or uh, boston and uh, you know, I pop in all the time other places in the states But this is this is the base right here. This is this is my neighborhood So we're really happy to share with you and we'll share a whole lot more On the glories of ancient rome the lessons we can learn the architecture that's still here Why rome fell all those great, uh subject matters will be tackled. Thank you guys so much for joining. We'll see you again real soon Subscribe to our newsletter and you'll know When the next lecture or location that will be covered. Thanks very much Thank you


Israel is often in the news for problematic reasons, but in Taiwan, the reality is totally different. I'm here in Taiwan to dig deeper and find out if Taiwan is the least anti-semitic country on Earth. Yalla, let's go. What do you think about Israel? Israel people are smart and hardworking.  It's, it's representative for, like, having a lot of intelligent people. Very many smart people and it's a rich country. What do you think of Jews? Jews. It's a religion. I think Jews are, like, everyone in the world. Taiwan is the same. So there's not much difference, either you are Chinese or Jews or Taiwanese or English. Jewish people, they're kind of rich, right? I also sat down with Jeffers Schwartz, the GCC founder from the Jewish Community Center in Taipei, to hear a bit more about the community. Taiwan is definitely the most least anti-semitic country in the world. Our goal here at the Jewish Community Center is to keep it that way. Here at the Community Center is the first official public Jewish establishment that's open to the public. And part of it is the museum and all the cultural events that we have. And we invite and encourage the local community to come and understand us. Here in Taipei, they have a full synagogue, a Jewish bookstore and ancient Jewish artifacts in their museum. They even have a kosher restaurant. It might surprise you to learn also that Taiwan is a home to nearly 700 Jews, as well as the smallest Holocaust museum in the world. While Jewish communities in some countries are facing persecution for their identity, in Taiwan, the Jewish community is clearly thriving.


The variational preparation of complex quantum states using the Quantum Approximate Optimization Algorithm, QAOA, has been shown to be a promising application of quantum computers. However, when the target Hamiltonian does not have translational symmetry, such as when it is open boundary condition, OBC, or random, the QAOA can become less efficient. To address this issue, researchers have proposed a generalized QAOA assisted by parameterized resource Hamiltonian, PAH, QAOA. This method allows for more efficient state preparation even when there is no translational symmetry. Additionally, they have designed a low-depth quantum circuit beyond one-dimensional geometry to generate gigahertz states with perfect fidelity. Finally, they have experimentally realized the proposed scheme for generating gigahertz states on ride-bug-dressed atoms. This article was authored by Tsinghang Sun, Yongyi Wang, Jian Kui, and others. We are article.tv, links in the description below.