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Quantum Entanglement

Speaking very generally, there are two ways to understand that entanglement experiment. One is that nothing changed when you measured and the states always had the value you measured, you just didn't know about it. This is known as hidden variables.

The second is that not only don't we know the state of the particles, they don't fundamentally have a determined state until you measure them.

The example with red and green balls given in this thread is clearly of the first type. In fact a very primitive type of hidden variables that could easily be proven wrong. The balls are not actually quantum (it's an analogy so that's fair). Now, this is obviously the most intuitive, so why don't everyone agree on this? The problem is at the very heart of all quantum weirdness. Take the double slit experiment. If the particle really had a determined choice of slit prior to going through the slit, why are we seeing an interference pattern?

Now, you can come up with creative explanations that still have hidden variables, but then you run into something called Bell's Theorem which states that if you have hidden variables, the universe must be able communicate faster than light(non-local). In the end, there are some people who believe hidden variables is the correct way of looking at it. Since the math is exactly the same as the variables are completely hidden for us, we have no way of determining who's right. At least for the time being.

Bell's theorem says we have to give up one of three things:

  • Hidden variables
  • Locality: Local action cannot influence a system far away faster than the speed of light
  • Free will: It makes sense to talk about what would have happened if you had chosen to do something else.

It's not correct to say that hidden variables have been proven false. It's almost correct so say that local hidden variables have been proven false as we don't usually discuss free will. To further look at this let's say I have a bag of hexagons. The top three sides are all black, and the bottom are all white.

  1. If I measure any random side. I will get white half the time and black half the time.
  2. If I measure two opposite sides, I will get two opposite colors.
  3. If I measure two sides next to eachother. I will get opposite colors one out of three times.

But, For a quantum hexagon:

  1. If I measure any random side. I will get white half the time and black half the time.
  2. If I measure opposite sides, I will always get opposite colors.
  3. If I measure two sides next to eachother. I will not get opposite colors one out of three times. It will be slightly less.

Suppose you have a system of two arrows, which have to point in opposite directions, and you're guaranteed to measure one of them pointing up.

Now, let's say you disturb the system a little bit. You put in some "paint", which will paint an upwards pointing arrow red and a downwards pointing arrow blue. If the states are predetermined, one arrow will get all the red and one arrow will get all the blue. If they aren't, both arrows will get some of both colors.

In quantum systems, for certain kinds of arrows and "paint", the second result happens.

That means that some of the sides don't have a color until you actually measure it, but opposite colors always have the same color.

Planck's Constant

What is Planck's Constant and why is it significant?

Well, this is quite a difficult question. I'll try to give an answer that is not too mathematical (which I tend to do usually).

First of all (sort of historically), Planck's constant is the proportionality between light of a specific wavelength (i.e. light of a specific color) and the energy a single light particle (a photon) has. This is already quite a profound statement. Energy is usually measured in Joule, while the frequency is measured in Hertz (= 1 / seconds). That means this proportionality constant has a unit of Joule * second. This unit is what physicists call the unit of an action. For someone who does not care about the mathematics of physics, an action is quite an abstract concept. You could say it is a measure for how much dynamics a system exhibits over a time interval (precisely: It's the integral of the difference between kinetic and potential energies in a system over a time interval). An interesting fact is that your physical reality around is the one that has the minimal action that is possible.

What we can understand from that really, is that Planck's constant can be seen as being related to dynamics of a system. However, it only arises in the case of quantum mechanics. I.e. it is what separates classical physics from quantum mechanics. Planck's constant sort of restricts this action in a sense. While in classical physics the action of a system can take any value whatsoever, in quantum mechanics you are always restricted to multiples of Planck's constant. In this way physicists say that classical physics can sometimes be recovered from quantum mechanics, if we assume Planck's constant to be zero (this is really only a thought experiment, we cannot change Planck's constant of course).

Planck's constant being related to dynamics of a system, it has a say in what kind of positions and momenta (that is velocities) particles in quantum mechanics can be.

Planck theorized that there is a minimum "resolution" to frequencies and energy. Through both experimentation and theory, he realized that all the frequencies and energies radiated were multiples of a single number, which came to be called Planck's constant. To simplify, you could emit at say, 10000 Planck's constants, and at 10001, but not at 10000.5.

In fact, Heisenberg's uncertainty principle says that position and momentum of a particle are related such that one cannot measure both at the same time better than Planck's constant, i.e. the product of the momentum uncertainty and position uncertainty needs to be larger than Planck's constant. This in effect means that if you measure one of the two very well, the other needs becomes more uncertain (as in actually will take values of a larger range). It kind of means if you try to trap a particle in a very small volume, it's uncertainty in velocity and direction will become huge and vice versa, because the product of the two needs to be larger than Planck's constant.

So, in a way one can argue that Planck's constant really is a fundamental unit of our Universe; our Universe is not continuous, but rather grid like on extremely small scales (heck, Planck's constant has a value of 6.63 * 10-34 Js, which is so ridiculously small I don't even know how to give a proper example). And the size of these blocks is directly proportional to Planck's constant.

Well, I hope this was somehow understandable or even answers what you want to know. This really is at the core of most of physics, so a proper explanation is always going to be lacking in some respects. Here's a video by PBS Space Time. If you have more specific questions, just ask. :)

A Seconds Time

Days/months/years are kind of standard, but the concepts of seconds, minutes, and hours has a varied history. Sit back, I got home from work early and the adderall is flowin' so I wrote up a nice history of units of time:Early man tracked time day by day using apparent time, or time based on sundials and other observations of nature. I can't find too much info right now but as far as I can tell there was no standard unit of time shorter than a day among any major civilization for a while.

  1. The Egyptians defined hours as 1/12th of either day or night, and had seasonal variations on the length of their hour.
  2. Greek astronomers were the first to establish the modern hour, by dividing the day into six parts and then dividing those parts into four more. They also had an early version of the minute, which was how long it took for the sun to travel one degree along the sky, or about four minutes.
  3. The Babylonians went a little nuts, also dividing the day into six parts, but then divided each part by sixty for their sub-units, up to at least six subdivisions, the smallest individual units being as accurate as two microseconds. However, instead of using a 1/24th of a day hour like the Greeks, they had a 1/12th day hour (120 min), but did use the 1/360th day minute, and something resembling a second called the barelycorn, about 3.5 modern seconds and still used in the hebrew calendar today as the helek.

In 1000, a Persian scholar named al-Biruni first termed the word second when he defined the period of time between two new moons as a figure of days, hours, minutes, seconds, thirds, and fourths. The minute was the first subdivision of the hour by 60, then the second, and so on. Roger Bacon did this again in the 1200's, but started with hours, giving a more accurate figure. The term third still exists in some languages, such as Polish, but fourths were apparently too small for any practical use and fell out of style with the general population.

The late 1500s what the first time a true standard second came to being with the advent of mechanical clocks, so that the time could be measured objectively from mean-time instead of deriving it from the apparent-time. The first clock with a second hand was built between 1560-70and 1579 saw the first clock with actual markings denoting the seconds. However, they weren't very accurate, and the second remained arbitrary from machine to machine and unable to be reliably measured. In 1644 it was realized that a pendulum of a specific length would have an oscillation period of exactly two seconds, and by 1670 William Clement had tinkered with the physics enough to build a clock precise enough that the second was now an established unit of time.

By 1862 it was established that the second would be the base unit of time for all scientific research, along with the millimeter and milligram, by The British Association for the Advancement of Science (BAAS), defining the second as 1/86,400th of a solar day by the 1940s.

From there we've just been refining the accuracy of what we call a second, accounting for the Earth's axis and ever-so slowly declining rotational velocity, to the point where it's not even measured by observations based on the earth and sun, but by the distance light travels in a vacuum or how many vibrations a cesium atom makes.

We've divided time so hard that to do so any further wouldn't make sense; events in subatomic physics just don't happen quickly enough for smaller units of time to be measured.

But yeah, that's where we got our units of time. It's such a ubiquitous thing that we've had literally our entire existence to hash it all out, and while today we're all in agreement about the standard subdivisions and have been for a long time, there were discrepancies in the past and in the context of your post it must have been a special kind of frustrating trying to figure out what two people mean by "hour". However, while we all agree on the day/hour/second situation, the annual calendar is still pretty sporadic in it's appearance. The lunar month may seem standard, but there are many South-East Asian cultures that have their own unique way of dividing the year.

I won't get into that, because it's mostly a headache and I'm kinda losing steam on this anyway, but long story short we're far from having a universal system here.

In the end we picked that number based on the previous definition, so the second is still derived from the Earth's rotation, even if it is no longer actually tied to it.

Climate Change Is Real And There Is Proof

I don't want to get into the politics of climate change. Instead I want to present you with an analogy that would explain the process and tipping point.

Imagine the climate of the earth is a huge, complicated, Mouse Trap Game/Rube Goldberg Machine designed to water your plants, feed your pet fish and hamsters and turn your thermostat up and down so the room stays a comfortable temperature.

Now imagine the whole machine is powered by the heat from burning candles, like one of those German Christmas toys.

The whole intricate system is running beautifully, your plants and pets are thriving and the room is nice and comfy. It's like this most of your life. But one day, one of the candles gets blown out, so the machine starts to malfunction. Maybe the plants don't get watered as often and the pets don't get fed so often. You don't really notice because the machine has always worked, and even though the room doesn't always feel quite as comfortable as it used to, you chalk it up to other reasons like what you cooked or hormones or something.

Meanwhile, since the hamsters aren't getting fed as often, their energy level is off, and since the hamster wheel was powering the part of the machine that replaces candles, another candle goes out and now the machine really isn't working well.

The fish aren't getting fed, the plants are wilting noticeably and the hamsters are entirely inactive. On top of this, the room is getting uncomfortably warm because the machine can no longer adjust the thermostat properly and now the few candles that remain lit are melting just because the room is so damn hot.

Soon the machine isn't working at all and you're busy putting out the small fires that have started from the melted candles.

Some little cactus plants survive and there are no doubt microorganisms eating your dead fish and hamsters, and live mold is growing too and some flies have gathered. So life hasn't been wiped out entirely. It's just a different form life that's thriving because of the new, unintended environment. You try to fix the machine, but can't because you're not the one who built it and it's really complicated. Intricacies upon intricacies down to the microscopic level. Fixing it is completely beyond your pay scale. So now this place you lived your entire life in is uncomfortably hot, has bugs and mold and a funky smell.

You can't live there anymore, so you pack up your things to move to a new place.

When you open the door to leave, there is nothing there but an inconceivably vast and dark expanse that has no oxygen or heat. There is nowhere else you can go.

But this analogy doesn't leave room for a solution, which is really depressing, so here's more:

At this moment, we're at the point where the second candle has just gone out. The hamsters are still fairly active, the fish are still swimming and only the most sensitive plants are showing signs of wilt. You still aren't paying much attention, but you are noticing a strange noise you haven't heard before.

You search for the source of the noise and it's a phone.

On the other end of the phone is a person telling you something is very wrong with your machine. They tell you your pets and plants are dying and if you don't do something now you won't be able to save them.

You look over at your pets and plants and they seem fine.

This person says there's a huge team of top scientists working hard around the clock to find a work-around to the malfunction, but he needs you to buy them some time by changing the way you live.

Everything he says you have to change is incredibly inconvenient, not as comfortable and he's even telling you to stop doing some of your favorite things-- forever. If you follow his instructions, your life will never be the same, but you will adapt and live out your days in the company of your beloved hamster, colorful fish and flowering plant. There's even a chance that the scientists will call back in your lifetime and talk you through a way to patch the machine so it's functional again.

If you don't follow his instructions, one day soon the other candles will melt and it will be too much damage for the scientists to fix.

This is the moment we're at today. The scientists have made the call and are working furiously to sequester carbon, find new viable and sustainable energy sources and perhaps even repair the damage to the environment. Even though they're incredibly talented, they still aren't the one who built the machine, so they won't have a solution for a while. They're asking us to change the way we live to buy them some time. I hope this mitigates some of the gloom of the original ending. Candidly, I'm not sure how many candles have gone out.

I'm really hoping the scientists can help us and that enough of us change the way we live to buy those scientists the time they desperately need.

Tactype

Everybody is putting captions on their photos without much though into the technology that goes into making them.

But when I was growing up I was amazed when the titles of the shows would appear over the actors. I thought that they had to reproduce it for each frame.

So how did I the words "I Love Lucy" or "The Honeymooners" or screen credits would appear over the live action footage before they could just slap it on without computers?

What they would make the titles with press-on letters (I forget the brand name) and shoot them with a camera. The title camera would be combined with the live camera in a device called a "luma key" that would switch the live camera off and the title camera on everywhere that the lettering appears, based on the brightness. This was with monochrome cameras. With color cameras there was a device called a "chroma key" that would switch based on hue, usually tuned to blue. The same device was used for example to put graphics behind the weather man. You had to be careful the talent didn't wear any blue clothing.

This website on switchers shows one with built-in luma key, and explains how it works: Scroll down to "Keys - Internal, External, Matte."

The letters were called; Tactype. You can buy a sheet of it here: VINTAGE TACTYPE Lettering 12 x 8 Sheet Dry Transfer 5514 Futura Medium.

Tactype, Linopress or Letraset were just a few of the typesetting brands. There were other press on letters.

They used a special tool kinda like a solid pen to transfer the letters from a transparency like film. You would manually rub the letters off the sheet. The letters would stick, most of the time not uniformly, to the paperboard or surface you were working with. As you can imagine the whole process took some time.

Logos and special art was normally printed with block type and hot type or lithograph for full color. As you can imagine it was really hands on.

As a side note this is why closed captioning use to be so expensive.

Big Blocks

I got into a sort of an argument. Well, that isn't entirely true. Maybe a heated discussion. About the difference of big blocks and small blocks. Well, at any rate. We agreed to disagree.

I will leave you to decide.

Big blocks were typically larger displacement, though there are some oddball "big blocks" like the Ford 360 that was smaller than the larger "small blocks" like a 383/400 GM.

(American) Big Blocks (other countries use different distinctions which might be were some of the confusion comes in) used larger bore spacing along with larger thus heavier rotating assemblies which did not lend itself naturally to higher RPM operation. In the Big Blocks everything was bigger the crank journals, the cylinder bore, the crank stroke, the connection rods were longer, everything was bigger.

Basically speaking: higher mass higher speed = higher chance of failure. Big blocks tend to have a higher deck height as well, which means they can have a longer stroke.

For example a Chevy small block has a deck height of 9.025, a big block on the other hand has a deck height of 9.8.

Chevy's old engine families were the ones that started a lot of the naming convention. The 305/350/383/400 were members of the small block family, and engines like the 396/427/454 are popular examples of the GM big blocks.

I don't know my Ford engines as well as I know my Chevy but yes Mopar had Big Blocks and small blocks. There was the B block and the RB block which were the Big Blocks which came in sizes such as 361, 383 and 400 and in the B series and the RB series which had the 413, 426 and the 440. The A series was the small blocks best known as 318, 340 and 360.

What you can see is that there is also no official physical dimension that renders something a big or small block. Which was the point I tried to make.