Only the abstrcat from this vedio.
Ep 01: Einstein's Nighmare
the light bulb
If you heated the filament with electricity, it glowed. The relationship between the temperature of the filament and the color of light it produces was still a complete mystery.
Max Planck: why the color of the light changes as the filament gets hotter? Why is blue so much harder to make than red? Why is ultraviolet light so hard to make? → "ultraviolet catastrophe"
a gold leaf electroscope
Charge it up with eletrons that are pushing the two gold leaves apart. First, take the red light and shine it on the metal surface and nothing happens. Even if you increase the brightness of the light still the gold leaves aren't affected. Then try the special blue light, rich in ultraviolet. Immediately, the gold leaves collapse. Light can clearly remove static electric charge from the leaves. But why is ultraviolet light so much better at doing this than red light? → "photoeletric effect"
These two problems couldn't be explained in that time. Light was a wave. Light can behave in a perfectly commom-sense wavy way. The shadow of one's hand, it's fuzzy round the edges. We understand this as the light hitting the side of one's hand and bending and smearing out slightly, just like water waves around an obstruction. But when it came to the ultraviolet catastrophe and photoelectric effect, the wheels started coming off. If light was a wave, more intensity should konck out more electrons. But that's not what happened. So thinking of light as a wave just wasn't adding up.
In 1905, Albert Einstein came up with a new theory to explain the photoelectric effect and what he suggested was revolutionary and even heretical. He argued that we have to forget all about the idea that light is a wave and think of it instead as a stream of tiny, bullet-like particles. The term he used to describe a particle of light was a quantum. A quantum was a tiny lump of energy. According to Einstein, each particle of red light carried very little energy because red light has a low frequency. So even a very bright red light with many red light particles, can't disloge any electrons from the metal plates. But each individual light particles of the ultraviolet light in the experiment carries more energy. Just a few of them are enough to kock the electrons out of the metal plate. This nifty idea also helped solve Planck's mystery of the light bulb. There was more red than ultraviolet because ultraviolet quanta took so much more energy to make, about 100 times more energy. No wonder there are so few of them.
the nature of reality itself
It began with the discovery of the weird and contradictory wave/particle nature of light.
Niels Bohr v.s. Albetr Einstein
Remember from the wave tank experiment where the signature wave only exists because each wave passes through both slits and then its two pieces interfere with each other. But every individual electron, each single particle is passing alone through the slits before it hits the screen. And yet, each single electrons is still contributing to the signature wave pattern. Each electrons has to be behaving like a wave.
Quantum mechanics says this...We can't describe what's travelling as a physical object. All we can talk about are the chances of where the electron might be. This wave of chance somehow travels through both slits producing interference just like the water wave. Then when it hits the screen, what was just the ghostly possibility of an electron mysteriously becomes real.
If I spin this coin... Then all the time it's spinning, it's a blur, I can't tell if it's heads or tails, but if I stop it, I force it to decide and it's heads. So before, it was sort of not heads or tails but a mixture of both. But as soon as I stopped it, I've forced it to make up its mind. This is what Bohr and his supporters claimed was happening with our electrons. He was effectively claiming that one can never know where the electron actually is at all until you measure it. And it's not just that you don't know where the electron is, it's weirdly as though the electron itself is everywhere at once. → the Copenhagen interpretation
But Eintein thought there should be a better underlying theory. At the heart of the Einstein's argument was an aspect of quantum mechanics called entanglement.
"Spooky action at a distance"
Bohr's cions, which only become real when we look at that and then magically communicate to each other, or Eintein's gloves, which are hidden from us, but are definitely left or right from the beginning?
In the early 1960s, John Bell decided to try and resolve the crisis at the heart of quantum physics. Bell reduced the idea into a single mathematical equation. p(a c - p(b,a) - p(b,c)≤1
Eintein's version of reality cannot be true. The two entangled photon's properties couldn't have been set from the beginning, but are summoned into existence only when we measure them. Something strange is linking them across space. Something we can't explain or even imagine other than using by mathematics. And weirder, photons do only become real when we observe them.
Ep 02: Let There Be Life
The Quantum Robin
How birds navigated with such accuracy?
Tiny variations in the Earth's magnetic field change the way electrons in the robin's eye are entangled and that's just enough to trigger her compass. If the massage changes, the chemical reaction tips a different way, changing the robin's compass reading. The robin is navigating by "Spooky" Quantum entanglement.
The Quantum Nose
The conventional theory that goes back to the 1950s, say that the scent molecule has a particular shape that allows it to fit in to the receptor molecules in our nose. In fact, it's called the lock and key mechanism. With the strong shape, it won't fit into the receptor. But with the right shape, it fits into the receptor, triggering that unique smell sensation. Different receptors are wired to different parts of our brains. But the lock and key theory has always had a problem.
Both benzaldehyde and cyanide have the same smell, but these molecules are both very different shapes, so the lock and key mechaism, as an explanation for how we smell, can' be the whole story.
The bizarre new quantum theory of smell is all about vibrating bonds. A particluar molecule will vibrate at a particular frequency. The two molecules have different shapes, but their chemical bonds just happen to vibrate at the same frequency. Different vibrations mean different smells.
The Quantum Frog
In metamorphosis, it's enzymes that dismantle the tadpole's tail. And that means breaking down an incredibly tough protein called collagen. But how do enzymes break chemcial bonds apart so incredibly fast?
To break bonds apart, it needs enough energy to get over the barrier. But this is where protons turn into ghosts. In the quantum world, protons don't have to go over barriers. They can tunnel straight through it. Tunnelling strikes at the very heart of what is most strange about quantum mechanics. A quantum particle can tunnel from one place to another even it has to pass through an impenetrable barrier. They are not solid objects like balls in our everyday world. They have spread out , fuzzy, wavelike behavior that allows them to leak through the energy barrier.
The most important advantage of tunnelling is its speed. It happens incredibly quickly, much faster than if protons go over the barrier. Quantum tunnelling turns strong knots into weak ones. So in the tadpole, the entire collagen scafford breaks apart easily.
The Quantum Tree
During the process of photosynthesis, when the proton hit the cell, it knocks an elecrton out of a middle of a chlorophyll molecule. This creates a tiny packet of energy called an exciton. The exciton then bounces its way through a forest of chlorophyll molecules until it reaches what is called the reaction centre. Now, that is where its energy is used to drive chemical processes that create the all-important biomolecules of life. The problem is, the exciton needs to find its way to the reaction centre in the first place.
The solution is that plants obey the most famous law in all of quantum mechanics, the uncertainty principle. It says you can never be certain that the exciton is in one specific place. Instead, it behaves like a quantum wave, smearing itself out across the cell. The exiton doesn't simply move from A to B. It's heading in every direction at the same time. The exciton wave isn't just going this way or that way, it's following all paths at the same time. That's what gives it such incredible efficiency.
