FactReactor
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Corrections and clarifications
A one-minute video has to leave things out. This is what each one simplified or had no room for, and where the popular version of a topic gets it wrong, newest first. Each one is also the pinned comment under its video.
Your Center Of Gravity Leaves Your Body
Yes - center of mass. Same point, two names. They only come apart in a gravitational field that changes across the object, and at human scale on Earth they agree to parts per million, so "center of gravity" is the honest word for it down here.
Your Lungs Have Never Been Empty
No, you are not still carrying the air from the day you were born. The air in your lungs is swapped with every breath - what has never been empty is the space. And that leftover litre is not dead weight: it holds your air sacs open and keeps gas exchange running in the gap between one breath and the next.
Your Body Is Diamagnetic
The question this video is going to get, so here it is up front: the frogs were fine. Berry and Geim measured the field induced inside the levitating frog at roughly 1.5 gauss - about the strength of a fridge magnet's stray field, nowhere near enough to do anything to a nervous system - and they put it in the paper in as many words: the animals were not electrocuted, and they emerged from their ordeal in the solenoid none the worse. Nothing was being forced. Every water molecule in the animal was simply being pushed, very gently and all at once, and the sum of those pushes happened to equal its weight.
Your Body Is A Cosmic Ray Detector
The beat there was no room for, and it is the correction a physicist would leave anyway: saying "its clock runs slow" is only half the picture. From where you are standing, yes - the muon's clock is crawling and that is why it survives the trip. But from where the muon is standing nothing about its life is stretched at all. It gets the ordinary 2.2 microseconds. What changes in its frame is the distance: the fifteen kilometres of atmosphere contract to a few hundred metres, and the fall is simply short. Same particle, same arrival, two ways of writing it down, and neither one is more true than the other.
You Are Made Of One Chirality
One correction before somebody else makes it, because it is a first-year chemistry fact: it is NOT true that every molecule in you is left-handed. D-amino acids are real and they are in you - D-alanine and D-glutamate in bacterial cell walls, D-amino acids acting as signalling molecules in your brain. The airtight version is the one the video actually says: every *protein* you have ever built was assembled from the left-handed set, because your ribosome will not take the other one. Narrower, and stranger.
You Have Never Felt Gravity, Only Your Chair
Before the physics-literate comment arrives — yes, gravity IS detectable over an extended body, through tidal gradients, and the equivalence principle is explicitly a local statement. That is exactly why every line in this video says "no nerve you own" rather than "undetectable, full stop." Here is the number it costs to be precise: across a 1.8 m body standing on Earth the tidal difference works out to roughly 5.5 x 10^-6 m/s2 — about 0.6 millionths of g, around one part in 1.8 million of your body weight. Real, measurable, and hundreds of thousands of times below anything you can sense.
You Are The Only One Who Hears Your Own Voice
Before anyone says it: no, this is not "bone conduction adds bass, that's why you sound deeper to yourself." That line is in almost every video on this topic and the primary measurements run against it — Reinfeldt et al. found the bone component leading in the 1-2 kHz mid-range, and Porschmann found air conduction dominating below 0.7 kHz. The bass-boost story is the one thing I left out on purpose.
Your Nasal Cycle Narrowed One Nostril On Purpose
Which side was open for you — and did you have to think about it, or did you already know? Roughly one adult in four or five has no clearly measurable cycle at all, so "both feel the same" is a real answer, not a failed test.
You Might Not Have A Palmaris Longus Muscle
Two cords or one? Post your count — and add where your family is from, because this number moves by population more than almost anything else in anatomy: about 3 % in parts of East Africa, over 40 % in the Arab Middle East. The comments on this one are genuinely more informative than the video.
Your Brain Won't Let You Tickle Yourself
The part I had no room for: this prediction is not universal equipment. People with passivity experiences — the sense that your own movements are being made for you — show no attenuation at all. In Blakemore et al. 2000 (Psychological Medicine 30:1131-1139) self-produced and externally produced touch rated the same for them. They can tickle themselves.
You Have Never Touched Anything
No, there is no gap — that is the part almost every version of this video gets wrong. The electron clouds DO overlap. The overlap is exactly what creates the push, and pushed further it is what a chemical bond is.