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Have fluffy kittens or puppies ever made you think, “I want to squeeze it until it bursts,” or even, “I want to sit on it and squash it”? Before you start wondering whether you’re antisocial, this feeling actually has a proper name: cute aggression. Why do cuter things make us more inclined to “bully” them? This article explores how the brain handles “cuteness overload.” Author: Einstein.？ Reviewed by: 星海中的蓝玫瑰 When you scroll past videos of adorable “hakimi” cats or “hakiwoof” dogs, do you ever want to squeeze them—or even swallow them in one bite? Then you realize how cruel that sounds and start to panic: “Do I have violent tendencies? Is something psychologically wrong with me?” Don’t worry~ This is actually a very common psychological phenomenon. Psychologists call it cute aggression ...

“The Moon of the fifteenth is full on the sixteenth.” Is this really just a catchy old saying? Why does this year’s Mid-Autumn full moon actually fall on the seventeenth? Through the Moon’s orbit, the synodic month, the Chinese calendar, and Mid-Autumn customs, this article explores the astronomy and millennia of calendar-making behind a full moon. Author: Einstein.？ Reviewed by: 星海中的蓝玫瑰 Introduction: A question behind an old saying The Mid-Autumn Festival is approaching: a time to gather with family and admire the bright full moon overhead. But wait—is it really a full moon? Looking it up, we find that the Moon on the fifteenth day of the eighth lunar month this year is waxing gibbous, with 98% illumination. It is full on the seventeenth, with 100% illumination. It seems that this yea ...

You may have come across a conclusion claiming that “there are as many natural numbers as even numbers.” But is that really so? From Galileo’s paradox to Cantor’s principle, this article takes you into a philosophical debate about infinity. Author: silverxz Reviewer: ΔδDelta\Delta\delta DeltaΔδDelta   How should we compare the sizes of infinite sets? For example, are there more natural numbers or more even numbers?   You may already have encountered the “conclusion” in many popular accounts: there are as many natural numbers as even numbers. The proof goes like this: consider the map n↦2nn\mapsto 2nn↦2n from the natural numbers to the even numbers. It establishes a one-to-one correspondence between all natural numbers and all even numbers: every natural number corresponds to an even num ...

Must a mathematical proof reach its answer step by step? The mathematician Erdős offered a wonderfully indirect idea: if we can prove that “a random choice has some chance of success,” then we have proved that a solution exists. Pour yourself a coffee and enjoy these proofs as works of art. Author: silverxz Reviewed by: phy东西 Paul Erdős Image source: zbMATH   Paul Erdős may not be a household name, but nearly everyone in mathematics knows who he was. A prolific and wide-ranging mathematician, he produced remarkable results in number theory, set theory, analysis, geometry, and many other fields. His place in combinatorics is beyond dispute.   There is no shortage of stories about Erdős: his unusual way of living and doing mathematics, the many forms his brilliance took, and much more. Y ...

This summer, the annual Perseid meteor shower has arrived right on schedule. Why do meteor showers return at the same time every year? And why are they named after constellations? Let us start with a speck of space dust and trace the cosmic paths behind meteors. Author: emmm Reviewed by: Situ Mo   A meteor may be the briefest and most brilliant “firework” in the night sky. A streak of light tears through the darkness without warning, vanishes an instant later, and leaves only startled cries behind. Right now, the Perseid meteor shower is approaching its peak, making this the best time of year to “run into” a meteor. But before you marvel at the sky, have you ever wondered what lies behind that flash of light? What is a meteor?   Before discussing meteors in detail, let us distinguish t ...

⚠️ This science article comes with a certain aroma! Why is poop usually yellowish brown no matter what we eat? Does the color come from food, or from an epic journey through the body? By the end of this article, you will know where the familiar color comes from—and what other stool colors may be trying to tell you. Authors: 阿氯 and 时光 Reviewer: 司徒陌   You probably do not study your poop closely after using the bathroom. Take an occasional look, though, and you will notice that it is usually yellowish brown. Braised pork and leafy greens generally end up producing the same color, although a few foods—notably dragon fruit—can tint your stool. That normal yellow-brown color comes mainly from stercobilin, a product of the reactions that bilirubin undergoes in the body.   So bilirubin appears ...

After rain, mysterious rings of mushrooms can appear in grass—and even in the game Sky: Children of the Light. Some have been growing for decades or even centuries. How do these strange rings form? Why do some make the grass greener while others are classified as turf diseases? Let us uncover the secrets behind mushroom rings. Authors: 阿氯、时光 Reviewed by: 星海中的蓝玫瑰   After the rain has cleared, have you ever seen clusters of mushrooms arranged in a circle on a lawn, as though someone had deliberately planted a ring of tiny umbrellas? In folklore, the phenomenon is often called a fairy ring or mushroom ring; in Chinese scientific usage, it is usually known as a xùn ring. What you may not know is that some large mushroom rings have been growing underground for more than a century.   What we ...

Can the digit string 1145141919810 be turned into an equation? Astonishingly, every integer with at least eight digits can become a true equation if we insert addition, subtraction, multiplication, division, parentheses, and an equals sign. From counterexamples and constructive arguments to a computer search, this article proves a mathematical claim that sounds absurd at first. Author: 硅基·飙尘葆光 Reviewer: ΔδDelta\Delta\delta DeltaΔδDelta The Silicon–Silence Balance Integer Theorem: A Brief Introduction and Proof   In everyday life, sophon interference from the Trisolarans often disrupts the numbers we try to transmit. Humanity has therefore devised many ways to disguise digit strings and thwart this evil plan. One method inserts arithmetic operators into a string until it becomes a true ...

Can we generate electricity without “boiling water,” using only a temperature difference? Why would a temperature difference set electric charges in motion? And how can such a seemingly weak effect power deep-space probes? Meet the Seebeck effect: one way that “heat” becomes electricity. Author: ST Reviewer: Shiguang   People often reduce power generation to “boiling water”: heat water, use the steam to turn a turbine, and convert that mechanical energy into electricity. The clearest example is fossil-fuel power generation, which burns coal, natural gas, oil, or another fuel to heat the water. Nuclear, geothermal, biomass, and even waste-to-energy plants often follow the same basic route. Wind turbines, photovoltaic cells, hydropower, and fuel cells, by contrast, do not “boil water” at ...