TIL: ELI5

Think about your closet for a moment - how many of your clothes do you wear often? You may notice that you wear about 20% of your clothes 80% of the time. This idea of a small proportion making up a significant part is called the Pareto Principle, also known as the 80/20 rule. It's named after an Italian economist, Vilfredo Pareto, who in the 1900s, observed that 80% of Italy's land was owned by 2...

The Anthropic Principle is a mind-boggling idea that tries to explain why certain features of our universe, like the precise balance of forces and conditions, are perfectly suited for the existence of life, and specifically, human life. Even a small change in some of these factors could have made life impossible! To put it simply, imagine you and your friends just finished playing a game of "Cosmi...

Unlike the straightforward idea of life originating on Earth, Panspermia suggests that life might not actually be local. It's the idea that life could have been seeded on Earth (and potentially other planets) by hitching a ride on meteoroids, asteroids, or comets. This might seem like quite a leap, but let's break it down a bit. So imagine life, in its most simple form, just like a seed. Now, for...

Now, let's delve into a world where things get a bit weird - quantum physics. We will talk about the Delayed Choice Quantum Eraser Experiment, a concept that puzzled many smart heads. Don't be scared by its fancy-schmancy name - we'll break it down in a way that anyone can grasp. Imagine, as an example, you're having a game of hide-and-seek with a clever child. Now, this kid is so cunning that onc...

Now, let's dive into a complex, yet fascinating realm of theoretical physics called the Penrose-Hawking Singularity Theorems. These theorems are about black holes, the mysterious regions of space where gravity is so strong that nothing, not even light, can escape. The theorems are named after two brilliant minds: Roger Penrose, a mathematical physicist, and Stephen Hawking, one of the most famous...

Let's imagine that you are taking a road trip. You'll likely plan out your route to minimize the time it takes to reach your destination. You want to get there as quickly as possible. In a similar manner, light operates on a principle known as Fermat's Principle or the Principle of Least Time. This principle is a fundamental concept in physics that helps to explain how light behaves. According to...

In the world of mathematical logic and philosophy, there's an interesting concept called the Munchausen Trilemma. It's named after the fictional Baron von Munchausen, who allegedly pulled himself out of a swamp by his own hair: an impossible task, just like resolving this trilemma! The Munchausen Trilemma suggests that our efforts to validate any truth claim or belief can only land in one of three...

Now, consider cleaning up your room. You put every single toy, clothes, book, in its rightful place. It's clean, beautiful and orderly. Now, imagine if you kept on tidying and untidying your room, an infinite number of times. After a (surprisingly) finite amount of time, an interesting thing would happen- your room will be in the exact same state it was in after you first tidied it up! This though...

Let's imagine playing a guitar. When you strike a string, you hear a distinct sound. Each string has a particular pitch or frequency associated with it. The scientific property determining the pitch of a string is called its 'eigenfrequency,' and the sound you hear is the 'eigenmode' of that frequency. These concepts highlight the basics of what's known as the Eigenvalue problem, a significant ele...

The Möbius Strip is an interesting concept in mathematics and geometry, named after the German mathematician August Ferdinand Möbius. It’s quite a curious thing, not unlike a paper ring, but with a twist that makes it entirely different. Imagine taking a strip of paper. If you were to mark one side with a pen and then join the two ends together to make a loop, you could definitely tell the marked...

The Arrow-Debreu Model is like a massive international swap meet, but for goods and services, and well into the future. In this big worldwide marketplace, instead of meeting only on the weekends, people commit to exchanges years, even decades, into the future, assuring each other that what they're promising will actually happen. Here's an example to better understand it: Imagine a farmer who grows...

Imagine that you are given a map, and your job is to color each region in such a way that no two adjoining regions have the same color. How many different colors would you need to successfully complete this task without any two adjacent regions being the same color? The Four Color Theorem answers that question. Introduced in the mid-19th century, the Four Color Theorem states that any geographical...

Neuroplasticity is a term that sounds complicated, but it's really quite a simple, though amazing idea once you get the hang of it. This concept is rooted deeply in neuroscience, the study of the brain. In simple terms, neuroplasticity is the brain's ability to change, adapt and rewire itself throughout a person's lifetime. Yes, it's like your brain is a software that's constantly updating! This h...

Zero-Point Energy (ZPE) is an intriguing concept from the realm of quantum physics, which can be a little mind-bending, so let's simplify it. Start by picturing what absolute nothingness might look like. Most of us would imagine a vacuum with no particles, no energy, and certainly no movement. Ironically enough, quantum physics tells us there's no such thing as an absolute vacuum. Even the empties...

Let's shift our attention to a fascinating concept from quantum physics: The EPR Paradox. This puzzling theory, proposed by Albert Einstein, Boris Podolsky and Nathan Rosen in 1935, revolves around the principles of "quantum entanglement" and "locality". Essentially, the EPR Paradox aims to challenge the very fundamentals of quantum theory. First, let's get to know "quantum entanglement". It basic...

Let's consider a concept drawn from the realm of mathematics, specifically from an area called 'fractal geometry.' This concept is known as the 'Mandelbrot Set.' Now, if you're starting to get nervous with the mention of complex math, breathe easy. We're going to explain everything in straightforward terms, so it's perfectly fine if your math skills are a little rusty. First of all, let's make sen...

The Fibonacci Sequence is a series of numbers in which each number is the sum of the two preceding ones. It usually starts with 0 and 1. In other words, just start at 0 and 1, add those together to get your next number, which would be 1, then you add that to the previous number to get 2, and so on and so forth. So, if we were to write it out, the sequence would look something like this: 0, 1, 1, 2...

The Pauli Exclusion Principle is a theory in the field of quantum mechanics, the branch of physics that deals with particles that are incredibly tiny - so small that even atoms seem huge in comparison. Now, this theory sounds complicated and perhaps something out of a science-fiction movie, but I assure you, it's a lot simpler than you might think. The principle was proposed by an Austrian physici...

Imagine for a moment that you're back in a time when the Earth was still formed but life didn't yet exist. The sky's filled with thunder, lightning, and the atmosphere's a toxic soup of methane, ammonia and other gases -- it certainly doesn't seem like a setting where life could blossom. That’s where scientists Stanley Miller and Harold Urey step in. In the 1950s, they set out to demonstrate a gro...

Spacetime is a concept in physics that combines space and time into a single, unified idea. It might sound complicated, but let's break it down to simpler terms. Everybody understands the idea of space. You move forward, backward, left, right, up, down. Those are your three dimensions of space. Time is the fourth dimension, something continuously progressing. We move forward in time just by existi...

The Doppler Effect, named after the Austrian physicist Christian Doppler, is something you've likely experienced without even realizing it. You know when an ambulance zips by and you suddenly notice the pitch of the siren changing as it passes you? That's the Doppler Effect in action. Let's break it down in simple terms. Imagine you're floating on a peaceful lake with your eyes closed, feeling the...

Have you ever piled up sand or soil, just to watch it cascade down as a landslide? Or observed water droplets combining to form bigger drops? Nature, in many situations, prefers things clumping together rather than scattered apart. This concept is also seen in the world of quantum physics, in the form of a peculiar state of matter called the "Bose-Einstein Condensate". Let's break this down. We le...

First off, let's establish what cryptography is. It's a method used to protect information and communications by using codes. The idea is to change data in a certain way, making it difficult for anyone except the intended recipient to understand it. Imagine you and your friend committed to a secret language that only the two of you know. For instance, you exchange "apple" for "hello" and "banana"...

The concept I’m going to explain is called the "Uncanny Valley". So the uncanny valley is a theory that comes from the field of robotics and artificial intelligence, but it's also applicable to fields like animation and digital design. Let's imagine a graph. On the vertical axis, we show how much humans emotionally accept or like an artificial figure (like a robot or animated character). On the ho...

Superstring Theory is a really cool idea from the world of physics. At its simplest, it's a theory about the tiniest bits of stuff that make up everything in the universe. You know that everything is made up of atoms, right? And those atoms are made of protons, neutrons, and electrons. But then, what are those protons, neutrons, and electrons made of? According to Superstring Theory, they are made...