Just tacking some detail onto "promote open science".
CERN was/is a large early user and supporter of the open source KiCAD electronics CAD tooling. The downstream impact of improved accessibility to solid ECAD tooling has been a large contributing factor to the growing ecosystem of open electronics.
A lot of really impressive test and measurement equipment to support their research is developed in the open (see https://ohwr.org/project). People on HN are probably most likely to have heard of the White Rabbit timing project, but there's fantastic voltmeter designs, a lot of FPGA projects for carriers, gateware, fun RF designs.
There's a lot of use for the acceleration and sensor knowledge in the medical sector. Technology first developed for high-energy research can be used to improve CT scans[1], better cancer treatment[2] and so on. This goes way back.
But if Berners-Lee hadn't started the WWW, someone else probably would have within a few years: the hard part was the development of the internet, i.e., a flexible low-cost wide-area network where anyone could start a new service (look in /etc/services to see all the services that people have defined over the years) without the need to get permission from anyone.
IIRC the first WWW server went live in 1990. By then there was already WAIS, Archie and Veronica (search engines for anonymous-FTP sites). In 1991, the first Gopher server went live. Gopher grew rapidly till the late 1990s.
The US government's Advanced Research Projects Agency started funding research into "packet-switched networks" in 1960 which would eventually lead to the internet, which went live in 1969 (under the name ARPAnet, but only a pedant would say that ARPAnet is not the early verion of the internet). Then the USG continued to fund the internet every year till it no longer needed funding in the early 1990s.
So, CERN and Berners-Lee (mostly the latter because no one at CERN other than Berners-Lee cared much about the WWW in its early days before it became a big hit) get some credit for the WWW, but in my reckoning it is a small amount of credit.
A lot of the benefit has come from learning expertise in applications.
Tons of the data science tools have roots in CERN. Tons of interesting statistical methods, tons of experience R&D with superconductors and all manners of sensors.
Tons of math/ computation techniques / modeling, etc would not be here without for CERN.
It would be sort of silly to expect that any of their actual discoveries or tests of the SM would have any actual application, but the ancillary benefits are there.
> practical social and economic benefits to humanity as a whole?
Why does it have to be practical? Scientific discovery is a perfectly valid end in its own even if it only ever means that we understand the universe better
The fact that almost always scientific discovery turns out to have practical purposes in the long run (centuries, not decades) is an added bonus.
It's not like it's a huge expense either. If switzerland decided to it could cover the yearly budget of cern, by itself at the cost of a fraction of a percentage of its gdp alone
High energy physics research has contributed some technology with social and economic benefits. Some of that has been direct results coming from pure research into fundamental properties of matter and electromagnetic radiation, some are indirect results that came about because when you build an institute like CERN, it spontaneously generates advances in other areas that solve more general problems (this is known as the "collect a bunch of smart people in a single place, with a lot of resources, to solve a unique problem" strategy). But no, most of the research, pure or applied, has not really had direct practical social and economic benefits to humanity as a whole.
That's entirely missing the point. We, as a society, have decided that we will balance our economic productivity into several different areas- welfare, infrastructure, military, industry, science/research, technology. We believe that investments in areas of research which have no direct benefit still can have positive outcomes- partly through fundamental discoveries, but also enriching us as a species. We also believe these investments will ensure that we have the freedom to be productive in the future.
A cynic might even say that CERN has played a critical role in keeping people from working on military applications, or working for the enemy.
If your criticism (it's hard not to read your comment as an implicit criticism) is that we should invest the results of our productivity more directly into areas which maximize social and economic benefits- sure, this is argued about all the time. The SSC was cancelled, at least partly because people failed to see the value in having a world-class HEP facility in the US.
No, but had cynicism? Off the member states the highest cost per used payer is still less than a bag of peanuts each year and most people with throw that at the TV over whatever upsets them without thinking. It's collective science not big pharma which is soaks tax payer money and then sells the discoveries back to you with 1000x markup.
And yes CERN has played an important part in the scientific conversation of where we are in the universe and what is looks like. If you don't think that's important I think flat earth cults are working just as hard to derail conversations they don't want to join in good faith...
