Ciro Santilli (@cirosantilli) - Newly followed articles

If we pick k elements of the set, the stabilizer subgroup of those k elements is a subgroup of the given permutation group that keeps those elements unchanged.

Note that an analogous definition can be given for non-finite groups. Also note that the case for all finite groups is covered by the permutation definition since all groups are isomorphic to a subgroup of the symmetric group

TODO existence and uniqueness. Existence is obvious for the identity permutation, but proper subgroup likely does not exist in general.

Bibliography:

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CERN by

Ciro Santilli 35  Updated 2025-01-10  +Created 1970-01-01

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How to convince teachers to use CC BY-SA by

Ciro Santilli 35  Updated 2025-01-10  +Created 1970-01-01

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A major difficulty of getting such this to work is that may university teachers want to retain closed copyright of their work because they:

want to publish a book later and get paid. Yes, the root problem is that teachers get paid way too little and have way too little job security for the incredibly important and difficult extremely difficult job they are doing, and we have to vote to change that
are afraid that if amazing material is made freely available, then they would not be needed and lose their jobs. Once again, job security issue.
believe that if anyone were allowed to touch their precious content, those people would just "screw it up" and make it worse
don't even want to publish their notes online because "someone will copy it and take their credit". What a mentality! In order to prevent a theft, you are basically guaranteeing that your work will be completely forgotten!
don't want students to read the notes and skip class, because spoken word has magic properties and imparts knowledge that cannot otherwise conveyed by a book
are afraid that mistakes will be found in their material. Reputation is of course everything in academia, since there is no money.
So it's less risky to have closed, more buggy notes, than open, more correct ones.
This can be seen clearly for example on Physics Stack Exchange, and most notably in particle physics (well, which is basically the only subject that really gets asked, since anything more experimental is going to be blocked off by patents/interlab competition), where a large proportion incredibly amazing users have anonymous profiles.
They prefer to get no reputation gains from their amazing contributions, due to the fear that a single mistake will ruin their career.
This is in stark contrast for example to Stack Overflow, where almost all top users are not anonymous:
List of top users: physics.stackexchange.com/users?tab=Reputation&filter=all and some notable anonymous ones:

Therefore the only way is to find teachers who are:

enlightened to use such licenses
forced by their organizations to use such licenses

The forced option therefore seems like a more bulk efficient starting point for searches.

No matter how much effort a single person puts into writing perfect tutorials, they will never beat 1000x people + an algorithm.

It is not simply a matter of how much time you have. The fundamental reason is that each person has a different background and different skills. Notably the young students have radically different understanding than that of the experienced teacher.

Therefore, those that refuse to contribute to such platforms, or at least license their content with open licenses, will inevitably have their work forgotten in favor of those that have contributed to the more open platform, which will eventually dominate everything.

Perhaps OurBigBook.com is not he killer platform that will make this happen. Perhaps the world is not yet ready for it. But Ciro believes that this will happen, sooner or later, inevitable, and he wants to give it a shot.

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