What arguments against the 'next LHC' say about funding Big Physics

A few days ago, a physicist (and PhD holder) named Thomas Hartsfield published a strange article in Big Think about why building a $100-billion particle physics machine like the Large Hadron Collider (LHC) is a bad idea. The article was so replete with errors things that even I – a not-physicist and not-a-PhD-holder – cringed reading them. I also wanted to blog about the piece but theoretical physicist Matthew Strassler beat me to it, with a straightforward post about the many ways in which Hartsfield’s article was just plain wrong, especially coming from a physicist. But I also think there were some things that Strassler either overlooked or left unsaid and which to my mind bear fleshing out – particularly points that have to do with the political economy of building research machines like the LHC. I also visit in the end the thing that really made me want to write this post, in response to a seemingly throwaway line in Strassler’s post. First, the problems that Hartsfield’s piece throws up and which deserve more attention:

1. One of Hartsfield’s bigger points in his article is that instead of spending $100 billion on one big physics project, we could spend it on 100,000 smaller projects. I agree with this view, sensu lato, that we need to involve more stakeholders than only physicists when contemplating the need for the next big accelerator or collider. However, in making the argument that the money can be redistributed, Hartsfield presumes that a) if a big publicly funded physics project is cancelled, the allocated money that the government doesn’t spend as a result will subsequently be diverted to other physics prohects, and b) this is all the money that we have to work with. Strassler provided the most famous example of the fallacy pertinent to (a): the Superconducting Super Collider in the US, whose eventually cancellation ‘freed’ an allocation of $4.4 billion, but the US government didn’t redirect this money back into other physics research grants. (b), on the other hand, is a more pernicious problem: a government allocating $100 billion for one project does not implicitly mean that it can’t spare $10 million for a different project, or projects. Realpolitik is important here. Politicians may contend that after having approved $100 billion for one project, it may not be politically favourable for them to return to Congress or Parliament or wherever with another proposal for $10 million. But on the flip side, both mega-projects and many physics research items are couched in arguments and aspirations to improve bilateral or multilateral ties (without vomiting on other prime ministers), ease geopolitical tensions, score or maintain research leadership, increase research output, generate opportunities for long-term technological spin-offs, spur local industries, etc. Put another way, a Big Science project is not just a science project; depending on the country, it could well be a national undertaking along the lines of the Apollo 11 mission. These arguments matter for political consensus – and axiomatically the research projects that are able to present these incentives are significantly different from those that aren’t, which in turn can help fund both Big Science and ‘Small Science’ projects at the same time. The possibility exists. For example, the Indian government has funded Gaganyaan separately from ISRO’s other activities. $100 billion isn’t all the money that’s available, and we should stop settling for such big numbers when they are presented to us.

2. These days, big machines like the one Hartsfield has erected as a “straw man” – to use Strassler words – aren’t built by individual countries. They are the product of an international collaboration, typically with dozens of governments, hundreds of universities and thousands of researchers participating. The funds allocated are also spent over many years, even decades. In this scenario, when a $100-billion particle collider is cancelled, no one entity in the whole world suddenly has that much money to give away at any given moment. Furthermore, in big collaborations, countries don’t just give money; often they add value by manufacturing various components, leasing existing facilities, sharing both human and material resources, providing loans, etc. The value of each of these contracts is added to the total value of the project. For example, India has been helping the LHC by manufacturing and supplying components related to the machine’s magnetic and cryogenic facilities. Let’s say India’s Departments of Science and Technology and of Atomic Energy had inked contracts with CERN, which hosts and maintains the LHC, worth $10 million to make and transport these components, but then the LHC had been called off just before its construction was to begin. Does this mean India would have had $10 million to give away to other science projects? Not at all! In fact, manufacturers within the country would have been bummed about losing the contracts.

3. Hartsfield doesn’t seem to acknowledge incremental results, results that improve the precision of prior measurements and results that narrow the range in which we can find a particle. Instead, he counts only singularly positive, and sensational, results – of which the LHC has had only one: the discovery of the Higgs boson in 2012. Take all of them together and the LHC will suddenly seem more productive. Simply put, precision-improving results are important because even a minute difference between the theoretically predicted value and the observed value could be a significant discovery that opens the door to ‘new physics’. We recently saw this with the mass of a subatomic particle called the W boson. Based on the data collected by a detector mounted on the Tevatron particle accelerator in Illinois, physicists found that the mass of the W boson differed from the predicted value by around 0.12%. This was sufficient to set off a tsunami of excitement and speculation in the particle physics community. (Hartsfield also overlooked an important fact and which Strassler caught: that the LHC collects a lot more data than physicists can process in a single year, which means that when the LHC winds down, physicists will still have many years of work left before they are done with the LHC altogether. This is evidently still happening with the Tevatron, which was shut down in 2011, so Hartsfield missing it is quite weird. Another thing that happened to Tevatron and is still happening with the LHC is that these machines are upgraded over time to produce better results.) Similarly, results that exclude the energy ranges in which a particle can be found are important because they tell us what kind of instruments we should build in future to detect the same particle. We obviously won’t need instruments that sweep the same energy range (nor will we have a guarantee that the particle will be found outside the excluded energy range – that’s a separate problem). There is another point to be made but which may not apply to CERN as much as to Big Science projects in other countries: one country’s research community building and operating a very large research facility signals to other countries that the researchers know what they’re doing and that they might be more deserving of future investments than other candidates with similar proposals. This is one of the things that India lost with the scuttling of the India-based Neutrino Observatory (the loss itself was deserved, to be sure).

Finally, the statement in Strassler’s post that piqued me the most:

My impression, from his writing and from what I can find online, is that most of what he knows about particle physics comes from reading people like Ethan Siegel and Sabine Hossenfelder. I think Dr. Hartsfield would have done better to leave the argument to them.

Thomas Hartsfield has clearly done a shoddy job in his article in the course of arguing against a Big Physics machine like LHC in the future, but his screwing up doesn’t mean discussions on the need for the next big collider should be left to physicists. I admit that Strassler’s point here was probably limited to the people whose articles and videos were apparently Hartsfield’s primary sources of information – but it also seemed to imply that instead of helping those who get things wrong do better next time, it’s okay to ask them to not try again and instead leave the communication efforts to their primary sources. That’s Ethan Siegel and Sabine Hossenfelder in this case – both prolific communicators – but in many instances, bad articles are written by writers who bothered to try while their sources weren’t doing more or better to communicate to the people at large. This is also why it bears repeating that when it comes to determining the need for a Big Physics project of the likes of the LHC, physics is decidedly one non-majority part of it and that – importantly – science communicators also have an equally vital role to play. Let me quote here from an article by physicist Nirmalya Kajuri, published in The Wire Science in February 2019:

… the few who communicate science can have a lopsided influence on the public perception of an entire field – even if they’re not from that field. The distinction between a particle physicist and, say, a condensed-matter physicist is not as meaningful to most people reading the New York Times or any other mainstream publication as it is to physicists. There’s no reason among readers to exclude [one physicist] as an expert.

However, very few physicists engage in science communication. The extreme ‘publish or perish’ culture that prevails in sciences means that spending time in any activity other than research carries a large risk. In some places, in fact, junior scientists spending time popularising science are frowned upon because they’re seen to be spending time on something unproductive.

…

All physicists agree that we can’t keep building colliders ad infinitum. They differ on when to quit. Now would be a good time, according to Hossenfelder. Most particle physicists don’t think so. But how will we know when we’ve reached that point? What are the objective parameters here? These are complex questions, and the final call will be made by our ultimate sponsors: the people.

So it’s a good thing that this debate is playing out before the public eye. In the days to come, physicists and non-physicists must continue this dialogue and find mutually agreeable answers. Extensive, honest science communication will be key.

So more physicists should join in the fray, as should science journalists, writers, bloggers and communicators in general. Just that they should also do better than Thomas Hartsfield to get the details right.