How to Tell Matter From Antimatter | CP Violation & The Ozma Problem

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Shared February 26, 2020

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This video is about the Ozma problem of distinguishing the chirality (ie left-handedness or right-handedness) of matter using weak interaction processes like beta decay (for example in uranium), or neutral kaon/k-meson decay. This is wrapped up in the phenomenon of CP violation, by which charge and parity are both violated by certain weak interaction processes - this enables antimatter to be unambiguously distinguished from matter, and left handed chirality from right handed.


The Ozma Search for Extraterrestrial Intelligence (SETI) Project

Sean Carroll on CP Symmetry (& why we shouldn’t trot out baryogenesis all the time)

Electroweak CP Violation on Scholarpedia

The Wu Experiment

Martin Gardner, The New Ambidextrous Universe

Lecture notes on CP Violation and the CKM Matrix, Cambridge (Mark Thomson)


L-glucose (vs D-glucose)

Radioactive Nucleus Decay

CP Violation in Semi-Leptonic Decays (SEE PAGE 426 for reference to definition of MATTER)

Kaon Decay Modes

Flipped bowling Jesus scene in Big Lebowski

Isotopes of Uranium

Beta Decay

The Wu Experiment


CP Violation in Symmetry Magazine

Physics Stack Exchange on CP Violation

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I guess this is how we should teach our children what is left and what is right. "Simply build an particle accelerator".

1 month ago | [YT] | 3,220

Simon T

Humans: Turn left
Anti-Alien: Turns left
Humans: no no no... the other left.

1 month ago (edited) | [YT] | 1,236

Jusnoor Dhillon

"simply, build a particle accelerator."

1 month ago | [YT] | 454

Adam Mercer

We're having a hard time finding evidence of alien life in general and MinutePhysics over here is discussing the ramifications of addressing left/right to anti-aliens.

1 month ago | [YT] | 1,444

Joshua Tahanlangit

Me: "turn to the left"
Alien: turns right
Me: Jimmy we've discussed this already. Do we have to visit a particle accelerator again?

1 month ago (edited) | [YT] | 352

Koen Bresters

minutephysics: "simply build a particle accelerator"
me: ?!

1 month ago | [YT] | 1,503

Magnus Mørkøre Johannesen

God might play dice, but he's really particular about his chirality, it seems.

1 month ago | [YT] | 1,042

matt winward

"Everything mirrors perfectly except for this one thing"




1 month ago | [YT] | 968

Caesar cch

7 year old me: Mom how to distinguish left from right?
Mom who also happens to be a physicist: Just build a particle accelerator...

4 weeks ago (edited) | [YT] | 278


"Enter the K-on."

And thus, moe was scientifically proven.

1 month ago | [YT] | 932

dataValis OFFICIAL

"So you guys just have to look at the 20.1% decay"
"Oh.. got it! 1.02% thanks!"

1 month ago | [YT] | 131


"simply build a particle accelerator"
what a flex

1 month ago | [YT] | 105


Scientist A: "Do you know what's the difference between Matter and Anti-matter?"
Scientist B: *shrugs *
Scientist A: "Neither do I, but it doesn't matter."

1 month ago (edited) | [YT] | 259


* Alien visits earth *
Alien: "Du you know the way to the White House?"
Human: "Well, do you know kaons...?"

4 weeks ago | [YT] | 171


"Simply build a particle accelerator" Can I get one at Ikea? And how many part(ticle)s does it consist of? Must be one hell of manual.

1 month ago | [YT] | 94


What i came here for: The Ozma Problem

What i understood: 🅰🅽🆃🅸 - 🅰🅻🅸🅴🅽🆂

1 month ago | [YT] | 230


1:01 I wish the text would stay longer in the window. I don't mind hit pause while watching the video, but it would be nice to have a longer timespan to actually be able to hit pause.

1 month ago | [YT] | 192


Counterpoint: I'm never going to ask someone made of antimatter to make me pie so i guess you could say this problem doesn't....


1 month ago | [YT] | 178

Arena Closer

1:18 "Not knowing left and right could impair intergalactic culinary relations"

This is of upmost importance.

1 month ago | [YT] | 18


Addendum: The aliens have an antimatter Samuel R. Jackson.

1 month ago | [YT] | 26