You should see that as you make things bigger, the graph of arrangements becomes more sharply peaked, centered around the most likely (i.e. the highest entropy) state. Joseph-Michel and Jacques-Étienne Montgolfier, also called the Montgolfier brothers, (respectively, born Aug. 26, 1740, Annonay, France—died June 26, 1810, Balaruc-les-Bains; born Jan. 6, 1745, Annonay, France—died Aug. 2, 1799, enroute from Lyon to Annonay), French brothers who were pioneer developers of the hot-air balloon and who conducted the first untethered flights. Modifications and improvements of the basic Montgolfier design were incorporated in the construction of larger balloons that, in later years, opened the way to exploration of the upper atmosphere.

At this point, you might be wondering what this has to do with entropy. Well, entropy is just a fancy word for ‘number of possible arrangements’. Entropy is a count of how many ways you can rearrange the ‘insides’ of a thing (its microscopic internals), while keeping its ‘outwardly’ (macroscopic) state unchanged. (Technically it’s the log of the number of these arrangements, but that’s just a mathematical convenience and doesn’t affect our discussion.) The first human passenger was also the first victim of balloon travel. Nearly two years after this flight, Pilâtre de Rozier died on June 15, 1785, when his balloon, filled with a combination of hydrogen and hot air, exploded during an attempt to fly across the English Channel, according to the Royal Society of Chemistry. Advances in ballooning Say we’ve got three sheep. These sheep are shuffling about in a farm, pretty much at random. And this farm is split into three plots of lands. So, for example, if you gave me a balloon, I could measure certain things about the gas inside it – its pressure, volume, temperature, and so on. These numbers record the macroscopic state of the gas. Given this handful of numbers, there are umpteen ways in which the gas molecules might be arranged inside the balloon. They could have different positions, and whiz about in different directions, with different speeds. So there’s a massive number of internal, microscopic arrangements (in this case, the positions and velocities of the gas molecules) that all result in the same external state (pressure, volume, and temperature of the gas). Entropy is a count of all these arrangements. The entropy of the air inside a balloon counts all the ways that the air molecules can be arranged while maintaining the same overall temperature, pressure, and volume. The Chimney Balloon was started up by an engineer in the 1980s, although many other companies have since set up offering similar products. In 2017, The Chimney Balloon Co. was bought by Chimney Sheep Ltd and although the products they offer are different they now work together.Just as when draught proofing a front door or your windows, there are many different products on the market designed to prevent heat loss from the chimney. It is also important to choose a product that still allows for a degree of ventilation. This will prevent any damp issues from occurring. Some, such as The Chimney Balloon, feature small vents, while natural products made from wool are breathable by their very nature. Meanwhile, there are only 28 possible arrangements for the state we started off in, with all 6 sheep on the top farm (the bar to the right of the graph). So we're less likely to find the sheep in this lower entropy state. It’s important to keep in mind that there’s no special guiding force driving these sheep to spread out and increase entropy. It’s just that there are fewer ways to keep the sheep concentrated, and more ways to spread them out. There are fewer arrangements where the sheep (energy) are concentrated, and more arrangements where the sheep (energy) are spread out. When you heat a solid, you're adding energy to it. We usually think of energy as something continuous, something that flows. But when you get down to the atomic level, quantum mechanics teaches us that energy comes in discrete chunks.

About a month later, on Nov. 21, Pilâtre de Rozier and theMarquis d'Arlandes, a French military officer, made the first free ascent in a hot air balloon. The pair flew from the center of Paris to the suburbs, about 5.5 miles (9 km), in 25 minutes. Benjamin Franklinwrote in his journal about witnessing the balloon take off: It turns out, you're most likely to find the sheep more or less evenly split between the two farms (the states labelled 2, 3, or 4 on the graph). Meanwhile, states where the sheep are all in one farm (labelled 0 or 6 on the graph) aren't as likely. (If you don't see this as yet, press one of the blue buttons to speed up the simulation.) Going down this road leads us to some of the biggest unanswered questions about the cosmos: how did our universe begin, how will it end, and why is our past different from our future? Counting SheepAnd that’s just 50 atoms. When we get to an object as big as an ice cube in a glass of water, with something like 10 So when we look at really tiny solids, energy doesn’t always flow from a hot object to a cold one. It can go the other way sometimes. And entropy doesn’t always increase. This isn't just a theoretical issue, entropy decreases have actually been seen in microscopic experiments. Why Big Is Different

This isn’t just about ice cubes. Imagine you dropped an egg on the floor. Every atomic motion taking place in this messy event could have happened in reverse. The pieces of the egg could theoretically start on the floor, hurtle towards each other, reforming into an egg as it lifts off the ground, travel up through the air, and arrive gently in your hand. The movement of every atom in this time-reversed egg would still be perfectly consistent with the laws of physics. And yet, this never happens. The Origin of Irreversibility In sheep land, we’ve removed the fence between two neighboring farms, each with 3 plots of land, and 6 sheep are roaming freely between them.There’s something curious here. Although the equal energy state is the most likely, it’s still very possible to find all the energy in one solid (the left or right extremes of the graph). In fact, there's about a 1 in 8 chance of this happening. So the entropy in this system can fluctuate, sometimes going up, other times going down. How effective chimney draught excluders are depends on a couple of factors. The main thing you need to concentrate on is ensuring you buy the right sized product for your chimney. You will need to measure your flue carefully. In some cases, it will be necessary to have a draught excluder custom made to fit. You might’ve heard an explanation that goes like this: whenever you drop an egg, or melt an ice cube, or shatter a wine glass, you’ve increased the entropy of the world. You might also have heard the phrase, “ entropy always increases”. In other words, things are only allowed to happen in one direction — the direction in which entropy increases. And yet, for some reason, when we get to large collections of atoms, a one-way street emerges for the direction in which events take place, even though this wasn’t present at the microscopic level. An arrow of time emerges.