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Seems like we've got a few of these imbalances now where you'd expect 50:50 but instead it's skewed to one side where nature had a different idea

Matter-antimatter ratio

Left vs right handed molecules

Now galaxy spin directions

Maybe there are others I missed too


The fact that we have found left-handed neutrinos but not right-handed ones seems like another one.

https://en.wikipedia.org/wiki/Sterile_neutrino


Cosmic Rays May Explain Life’s Bias for Right-Handed DNA

"the rapid decay of pions is governed by the weak force — the only fundamental force with a known mirror asymmetry"

https://www.quantamagazine.org/cosmic-rays-may-explain-lifes...


For the matter-antimatter ratio, you would not expect 50:50, or would you? Because 50:50 would be a highly unstable system? In any case, you would expect that unstable states would be highly unlikely, and it would converge into a stable state.

I'm not sure about the other examples. But maybe it's a similar reason that it is not a 50:50 ratio?


A 50/50 matter/anti-matter system could still house stable local pockets of mostly matter or anti-matter. The problem is, from what I understand, that the universe seems to have sprung into existence with way more matter than anti-matter, and we don't know why.


Could it be that the observable universe is one of these stable local pockets and the antimatter to balance it out is simply not observable to us?


Mathematically possible.

If you flip 2n fair coins, you expect n+δ heads and n-δ tails, where δ is (IIRC) sqrt(n/2). Going much away from that becomes infintessimally unlikely.

Probability is a subject famously easy to get wrong, so be careful with what I'm about to suggest: I *think* you could argue that in the moment prior to the inflation epoch spreading everything out just enough that pair production stops*, any given particle in our horizon is a coin toss of matter or antimatter.

Number of observed atoms in the universe is about 6e79 (http://www.wolframalpha.com/input/?i=how%20many%20atoms%20in...), so 6e79 = sqrt(n/2) -> n = 7.2e159 due to protons, and the same again for electrons; as we don't see significant signs of antimatter, any around must have annihilated a long time ago, so in this scenario we should expect to see ~7e159 (red-shifted) photons from the supermajority of particles which have annihilated.

It's outside my field to know how that compares to cosmologist's observations.

* won't that be at different times for protons/neutrons and electrons?

I can't get good answers on the expectations for either "why are protons and electrons counts the same" or "what is the observable consequence if they're not?"


Potentially, but it seems like an untestable hypothesis by itself.


Not a physicist, but here is my understanding of the cosmology physics:

High energy can spontaneously form matter antimatter pairs. In the early universe, the heat of the universe was very high, so this was common, constantly happening.

The problem as always if fine tuning. If the early universe was 60-40, that would be understandable. If the early universe was precisely 50-50, that’s fine too. But the universe was 50.0001-49.9999 or something like that, and then all annihilated. It’s too big a difference to easily be random chance, and too small a difference to be easily explained by a starting condition what wasn’t precisely tuned by some mechanism.


Not a physicist either but pair production also occurs in "non extreme" conditions and is still quite common.

If find this question fascinating. Matter can only ever exist with respective anti-matter. Question is where has all the antimatter gone? Are there processes were it does indeed behave different from matter? So where is it? Since a photon and antiphoton are the same and do not absorb each other, we should be able to see it, shouldn't we?

I still want to believe in the antimatter universe where there is some evil twin of mine.


In all known physical processes, the baryon number is conserved. Particles with a positive baryon number are the heavy particles in matter. Think protons, neutrons, and so on. Particles with a negative number are antimatter. Think antiprotons, and antineutrons. And particles with a 0 baryon number are not made of quarks. Think leptons like electrons and neutrinos, or bosons like photons and the Higgs boson.

This means that all known ways to create or destroy matter, also creates or destroys an equal amount of antimatter.

It turns out that most attempts to extend the Standard Model allow violations of baryon conservation. This could explain the dominance of matter in our universe. However none of those attempts have been able to make any predictions that matched experiment. And so it remains true that all known physical processes perfectly conserve the baryon number.

(It is also possible that baryon number really is conserved, and dark matter is actually dark antimatter. But we lack a theory of what dark matter could be that predicts this.)


Even if in the strong, weak and electromagnetic interactions the baryon number is conserved, there is the interesting fact that for the 8 particle set composed of the 3 kinds of u quarks, 3 kinds of d quarks, 1 electron and 1 neutrino, the sum of all kinds of quantities that are expected to be conserved, like electric charge, color charges and spin sum to zero. This set of 8 particles is also equivalent with the set of the components of one proton, one neutron, one electron and one neutrino.

This property of this set of 8 particles is analogous to the similar property of the set of 2 particles composed of a particle and its anti-particle, and to the similar property of the sets of 4 particles that can be involved in a weak interaction (the intermediate weak bosons convert one 4-particle interaction into a couple of 3-particle interactions, but when looking at the overall inputs and outputs, all the weak interactions are 4-particle interactions), which ensure the conservation of various quantities over such interactions.

This means that it is possible to conceive an additional kind of interaction, which unlike electromagnetic interactions between 2 particles and weak interactions between 4 particles, involves 8 particles, so it has a much smaller probability of occurring, i.e. it is a much weaker interaction than the weak interaction, and through which, when provided with enough energy, quarks + electrons + neutrinos could be generated simultaneously without generating anti-matter.

While there is no evidence yet for such an interaction, it is conceivable that at least during the circumstances of the Big Bang, such an interaction could have existed, so all the quarks and leptons could have been generated from some unknown bosons, just with enough initial energy and with conservation of all quantities for which there are solid reasons to believe that they must always be conserved, like energy, linear momentum, angular momentum, electric charge and color charges. (Unlike for the baryon number, for which there is no other reason to believe that it must be conserved, except that the strong, weak and electromagnetic interactions happen to have this behavior.)


You would expect a 50/50 ratio because when energy is converted into matter, it's typically in the form of matter/antimatter pairs.

There's nothing special about matter or antimatter. Same energy, just opposite charge. All else being equal, they should be created in equal amounts. As far as we're aware, there is no special property that would make the universe preferentially create more matter than antimatter.

There's also no requirement that the configuration of matter and antimatter be "stable" for whatever definition you want to apply. The only rule is that conserved quantities stay conserved.


but I was under the impression that equal parts of matter and antimatter annihilate, which would make a 50:50 system remain as such, which is why its such a mystery?


Isn’t there a different observation for why planets tend to orbit in the same direction in a solar system?


It's easily provable that any matter rotating other way gets expelled or thrown to center (Sun). So majority wins.


> Left vs right handed molecules

Organic chemistry found on meteors shows that non-terrestrial sources are equally left vs right-handed.

However, the rest might be caused by one or more errors in our premise. The most likely culprit being cosmological principle.


I honestly start thinking that the idea "everything should be symmetric in some way..." is completely wrong, and an example of wishful thinking "...because it would be cool if it did". Even if nature is in some way balanced on a scale large enough, it's extremely unlikely for us not to be in some local pocket. Most likely we're a part of some bigger structure that has certain properties, and this affects our perception of the laws of physics.


> Most likely we're a part of some bigger structure that has certain properties, and this affects our perception of the laws of physics.

Which would also be the reason we have the laws of physics we do in general.

Anything seemingly ad hoc in our universal (from our vantage) viewpoint is potentially explainable as a pocket among all other possible distributions/combinations of relations.


there's also that famous experiment by Chien-Shiung Wu, veritasium did a video on it somewhere


Dark matter / regular matter


I really don't agree. People behave differently when they know they are being recorded. They are less likely to admit mistakes or ask dumb questions.

There's just this odd formal air about them and I get annoyed when certain people try to record everything. Sometimes people just need to be able to speak freely.

There's a time and place for recording stuff - technical walk throughs, bug reports, demos, meetings where attendees are employed by different companies etc. Having your standup recorded just encourages one sentence answers (and yes, that's a bad thing if you want people to actually tell you if they have a problem)


PhD should never be considered a sign of intelligence. Anyone can get one if they pay enough and don't have any better prospects


They paid me (poorly). As to better prospects, meh. I graduated with an engineering degree in the naughts.


Anyone can get one if they pay enough and don't have any better prospects.

Not true at all (in terms of STEM degrees from legitimate schools).


Skip Crossroads of Twilight. Read the summary on Wikipedia. It's a gimmick that covers the same day and events from lots of different perspectives. None of them are good. That book serves as a slap in the face for the author who made a course correction for book 11 and got it back on track. Then Sanderson naturally has a faster pace than Jordan and brings it home strong. 11-14 are great again for those who survive 7-10.


Because 'line go up' is the only globally shared value left in modern society


> Humans need a world where being lazy causes their standard of living to deteriorate in a very noticable way, where working hard causes their standard of living to improve

The opposite of capitalism then? Right now, as soon your absolute asset gains equal your expenses, you can coast along doing nothing forever. You'll probably get richer too if you can live below that level. The whole goal of society is to retire and literally stop working hard (minus a few workaholic CEOs who will die alone at their desks).


Once you learn that online outrage doesn't actually impact your life that much, its easy to ignore. Gone are the days of public apologies and now we just sweep criticism under the rug and carry on.


I think trump taught us that very few people will stop you physically if you just ignore what they have to say.


Jira now makes your requirements for you. They all seem perfectly logical and not connected to anything your actual customers need.


So no difference to the real thing? ;)


I hope it can figure out story points for me, as I never understand what they mean and what value to put there.

I think AI will be better at story point estimation than me.


You joke but the drive to increase profits at any cost is having pretty insidious impacts on the world. Enshittification is everywhere now with companies being forced to degrade customer experience to appease shareholders. Nothing wrong with making a profit but making additional profit every single quarter is making the western world hostile to most people on average wages. It's too expensive to even live here with only a small percentage of people doing well under these circumstances.


The median US household income has increased significantly above inflation in the last few years and the lowest-income households have done significantly better than that because we reached "full employment" and that allows more job changes.

The largest price issue left is housing costs and that has nothing to do with "corporate profits", it's about bad land use regulations.

(Another funny thing about the "ever increasing corporate profits" argument is that it's literally anti-Marxist, as Marxism says the problem with capitalism is its profits continually /decline/ due to over-production.)


I think we might be seeing the end of hyper specialisation. The need for pure coders will decrease in the same way pure scrum masters, business analysts or project managers did. The skills are still there and used but they are aspects of roles rather than the whole role.

That is my optimistic read on AI. Return of the generalists (note - don't read that as a 'jack of all trades' but rather someone who is very good at 2-5 things rather than an expert at 1-2). Have a broader base and know how to use AI tools to do the prescriptive parts.


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