this post was submitted on 27 Sep 2023
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[–] dingleberry@discuss.tchncs.de 43 points 1 year ago (2 children)

Antimatter still has a positive mass. It's not some exotic negative mass matter.

[–] Nawor3565@lemmy.blahaj.zone 58 points 1 year ago

Well, yes, as far as our theories go. But we also "knew" that light was a wave that traveled through the luminiferous aether, which permiated all of space... Until we tested that theory with the Michelson-Morely experiment, and it turned out our theories were completely wrong and physics as we knew it was completely upended.

Point being, it's important to actually test our theories instead of assuming they're completely correct just because most of their predictions are accurate.

[–] i_love_FFT@lemmy.ml 4 points 1 year ago* (last edited 1 year ago) (1 children)

It has a positive mass, and in every other way it acts just like normal matter going backwards in time (cpt inversion).

If, despite its positive mass, it was pushed back by gravity, then it would have given even more weight to the theory that antimatter is just matter moving backwards.

Since gravity is such a wonky interaction, I'm not even sure this result disproves the time-reversal theory entirely!

[–] ryannathans@aussie.zone 10 points 1 year ago (2 children)

Why would inverting charge make particles go backwards in time? Electrons have opposite charge to protons and they don't seem to. Positrons have the opposite charge to electrons and as far as I know they don't go backwards?

I think you're misinterpreting cpt reversal symmetry, which is if you mirrored the universe in terms of charge, time and parity it would essentially evolve the same

[–] i_love_FFT@lemmy.ml 4 points 1 year ago (1 children)

It's been many years since I was invited with particle physics, so it's a bit muddled in my memory... i could be wrong on the details here. It could be the CP symmetry instead of the CPT symmetry.

It's not that positrons go back in time, but more like "if an electron went backwards in time, it would look exactly like a position". The Feynman diagram of an electron and position annihilaton is the same as that of an electron bouncing on photons, expect the angle is rotated such that the electron bounces backwards in time.

https://commons.m.wikimedia.org/wiki/File:Feynman_EP_Annihilation.svg#mw-jump-to-license

[–] ryannathans@aussie.zone 3 points 1 year ago

Ah yeah makes more sense

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[–] ShadowRam@kbin.social 28 points 1 year ago* (last edited 1 year ago) (3 children)

If an anti-gravity particle does exist (that expels both normal mass and itself), it would be incredibly hard to find.

They would push away from each other and disperse outside of the solar system.
Like 1 particle per 1000sq km kind of thing.

Which would push all the galaxies away from each other, always accelerating away from each other, but in a decreasing fashion....

It would also press inward on galaxies making it look like mass on the outer rims of galaxies having more gravity than they should.

And there would be a SHIT ton of this matter, that would be dark because it's so spread out,

..wait a minute ..

[–] BastingChemina@slrpnk.net 5 points 1 year ago (2 children)

Could it be a particle that has negative mass ?

In this case it would not appear in the CERN.

I'm way out of my field so please anyone, correct me if I'm wrong.

The CERN is creating particles from pure energy, E=mc² means that if you focus a lot of energy in a single point some of the energy is turned into matter. From my understanding the generated matter is random particles.

Now if we want to create a particle with negative mass we need negative energy. What is negative energy? I have no idea but if we manage to focus a huge amount of negative energy we will get particles with negative mass.

[–] ShadowRam@kbin.social 3 points 1 year ago

Do we need negative energy?

Don't particles appear out of thin are and then collide again and disappear?

0 = E = -mc² + mc²

You can have negative mass without requiring negative energy.

[–] ryannathans@aussie.zone 1 points 1 year ago

If you created a negative mass particle at the same time as a positive mass particle, you'd essentially be able to do so with 0 or near 0 energy because they have opposite signs and would cancel out - negative energy plus positive energy. Free energy?

[–] Tiuku@sopuli.xyz 2 points 1 year ago* (last edited 1 year ago)

This stuff would be convenient in keeping our wormholes from collapsing.

[–] someacnt@sopuli.xyz 1 points 1 year ago

Fun theory, only if it holds some water..

[–] AceQuorthon@lemmy.dbzer0.com 24 points 1 year ago (1 children)

Reading stuff like this is super funny when you have absolutely no idea how any of this stuff works.

"Wow, antimatter falls down! Gravity sure do be like that!"

[–] NattyNatty2x4 4 points 1 year ago

It confirms what pretty much everyone already assumed would happen, but it's one of those things that should be tested just in case. Plenty of times tests have been performed and unexpected results appeared, leading to advancements in science. So if (on the very off chance) it didn't interact with gravity as expected, that might have led to improvements in our understanding of general relativity and/or quantum mechanics, since gravity is one of the big problems we have in trying to marry the two theories

[–] Colorcodedresistor@lemm.ee 17 points 1 year ago* (last edited 1 year ago) (1 children)

My understanding of CERN comes explicitly from Neon Genesis Evangelion (1995) and Steins Gate (2011) ...and possibly The Backrooms (2022)

I do not have the gumption to mess with shadow companies jimmies.

[–] PeWu@lemmy.ml 8 points 1 year ago

Steins gate was introduction to CERN for me. And it scared the shit out of me. No, thank you. You do you.

[–] makeasnek@lemmy.ml 11 points 1 year ago (1 children)

If you think this is cool, there is a !boinc@sopuli.xyz project for the LHC (worlds largest particle accelerator) run by CERN. You can donate your computer's spare computational power and maybe find a new subatomic particle! I've been running it for years, very fun project to be involved in, no PhD required.

[–] MDKAOD@lemmy.ml 2 points 1 year ago

A side note, with the announcement of the raspberry pi 5, there's a lot of chatter about how the pi boards are big contributors to boinc.

[–] Omega_Haxors@lemmy.ml 3 points 1 year ago* (last edited 1 year ago)

~~Well that puts some validity in the "antimatter is matter going back in time" camp.~~

EDIT: Lol I misread. This actually disproves it.