Anonymous at Mon, 21 Oct 2024 12:48:55 UTC No. 16442466

>>16442025
We don't know. The Sakharov conditions require CP violation ie matter-antimatter disbalance. The known sources of CP violation, CKM and PMNS phases, aren't enough. The strong CP term not being there is also a big theoretical problem.

EBOK at Mon, 21 Oct 2024 12:52:54 UTC No. 16442470

It's actually called metal, not matter. There's no such thing as anti matter, but there is anti metal. It can be considered anti matter full

EBOK at Mon, 21 Oct 2024 12:54:08 UTC No. 16442471

>>16442470
Matter includes energy.

EBOK at Mon, 21 Oct 2024 13:01:36 UTC No. 16442476

Where's the anit matter? It's concealed behind a wall of technological advancement and exists in the core of the planet. Inducing gravitational sleep.

Anonymous at Mon, 21 Oct 2024 13:30:39 UTC No. 16442508

>>16442466
Sabine says it's a silly assumption.

Anonymous at Mon, 21 Oct 2024 13:50:13 UTC No. 16442532

>>16442508
Cool. And I say it's not. Going to use actual arguments instead of appealing to authority?

Anonymous at Mon, 21 Oct 2024 13:58:29 UTC No. 16442547

>>16442532
What's the motivation behind assuming there should have been equal amounts?

Anonymous at Mon, 21 Oct 2024 14:06:11 UTC No. 16442556

>>16442547
Because particles don't just exist on their own. They're field excitations. So any imbalance must indicate different field dynamics. Our current models don't.

I watched the video and she claims the imbalance is somehow an initial condition to the Dirac equation. This is plainly wrong. One can always transform between the Dirac equation for matter to the Dirac equation for antimatter via CP transformations regardless of boundary. The boundary must be the same for both.

Anonymous at Mon, 21 Oct 2024 15:11:17 UTC No. 16442624

>>16442556
>The boundary must be the same for both.
Why though? Why can't particles exist on their own without anti particles? Is it some symmetry condition in the lagrangian?

Anonymous at Mon, 21 Oct 2024 17:57:24 UTC No. 16442838

>>16442624
Because it’s the same equation. Let’s say we have the Ampere-Maxwell law (see pic). Curl is an orientation-dependent parameter, so if we would have picked a left-handed coordinate system for whatever reason then we would need a minus sign on the LHS. Clearly, this is just a choice of coordinates and not a physical change. The CP transformation is a similar “orientation-changing” transformation, except on coordinates in Minkowski space. So it’s the same equation up to a transformation.

Anonymous at Mon, 21 Oct 2024 17:58:26 UTC No. 16442841

>>16442838
*orientation-dependent operator
forgot pic lol

Anonymous at Mon, 21 Oct 2024 18:04:26 UTC No. 16442846

>>16442624
Oh and to answer your question on particles and antiparticles. Spinor representations (fermions) are complex. Antiparticles are Hermitian conjugates of particles. You need both to have a purely real term in the action. All this is talking about Dirac fermions. It gets much more complicated with Weyl fermions, which is where we get CKM and PMNS CP violation.