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| LHC magnets. Image: CERN. |
I currently don’t have time to go through this in detail, but let me pick the most egregious mistake. It’s right in the opening paragraph where the authors claim that a next larger collider would tell us something about the creation of the universe:
“[P]article physics strives to push a diverse range of experimental approaches from which we may glean new answers to fundamental questions regarding the creation of the universe and the nature of the mysterious and elusive dark matter.
Such an endeavor requires a post-LHC particle collider with an energy capability significantly greater than that of previous colliders.”
We previously encountered this sales-pitch in CERN’s marketing video for theFCC, which claimed that the collider would probe the beginning of the universe.
But neither the LHC nor the FCC will tell us anything about the “beginning” or “creation” of the universe.
What these colliders can do is create nuclear matter at high density by slamming heavy atomic nuclei into each other. Such matter probably also existed in the early universe. However, even collisions of large nuclei create merely tiny blobs of such nuclear matter, and these blobs fall apart almost immediately. In case you prefer numbers over words, they last about 10-23 seconds.
This situation is nothing like the soup of plasma in the expanding space of the early universe. It is therefore highly questionable already that these experiments can tell us much about what happened back then.
Even optimistically, the nuclear matter that the FCC can produce has a density about 70 orders of magnitude below the density at the beginning of the universe.
And even if you are willing to ignore the tiny blobs and their immediate decay and the 70 orders of magnitude, then the experiments still tell us nothing about the creation of this matter, and certainly not about the creation of the universe.
The argument that large colliders can teach us anything about the beginning, origin, or creation of the universe is manifestly false. The authors of this article either knew this and decided to lie to their readers, or they didn’t know it, in which case they have begun to believe their own institution’s marketing. I’m not sure which is worse.
And as I have said many times before, there is no reason to think a next larger collider would find evidence of dark matter particles. Somewhat ironically, the authors spend the rest of their article arguing against theoretical arguments, but of course the appeal to dark matter is a bona-fide theoretical argument.
In any case, it pains me to see not only that particle physicists are still engaging in false marketing, but that Scientific American plays along with it.
How about sticking with the truth? The truth is that a next larger collider costs a shitload lot of money and will most likely not teach us much. If progress in the foundations of physics is what you want, this is not the way forward.
Note that it's not just any "particle physicists" responsible for this misleading article. If you look at the biography of the authors at the back of the article, one of them, it says that one of them, Frank Zimmermann, "is a senior accelerator scientist at CERN and the deputy leader of the Future Circular Collider (FCC) Study."
ReplyDeleteThanks for pointing out, I had missed that.
DeleteIt is I think a fair assessment that around three seconds into the existence of the observable universe that particles interacted in the TeV range and that electroweak symmetry existed. By scattering particles at comparable energy we in effect recover this symmetry for a brief time, around 10^{-26}sec. Higher energy scattering experiments do then give data on particle physics at earlier periods of the observable universe. We detect signatures of this by how these excited states of quantum fields or particles relax or decay into daughter products.
ReplyDeleteAs for finding out how the universe emerged from some vacuum state, or equivalently how spacetime and the physical vacuum of the observable universe emerged, that of course requires a Planck scale collider. That is not likely to be built. Based on current technology such an accelerator would encompass this galaxy. Also the decay of a Planck mass quantum state, such as a quantum black hole, would produce about a mole of particles. The detection of these and making inferences about quantum gravitation, and then ultimately quantum cosmology, would be daunting. However, the coalescence of black holes excites quantum modes on holographic screens, such as above horizons, and this should have consequences with gravitation. This quantum hair on black holes may result in the emission of gravitons, and in fact gravitational waves are just classical large Nħ ensembles of gravitons. Quantum information may then be carried off by gravitons in the form of BMS supertranslations.
I am somewhat undecided on this matter of the FCC. I suppose it is similar to my stance with respect to the field of candidates the Democrats have proposed to challenge the t'Rump in the 2020 election. I have made no decision on that. I ponder whether it is better to develop new methods for accelerating particles so the experimental science can continue without scaling the technology so enormously. We really do not know if there is or is not physics in the trans-LHC energy regime that ties some loss knots with the standard model.
"Big science." Its acolytes are the ones who regularly testify to governments about what investments are appropriate. Leon Lederman broke his pick on the Superconducting Supercollider, which Congress cancelled around 1992 when the price tag (then) exceeded US$10B.
ReplyDeleteFCC isn't the only example of "big science" threatening to bankrupt science in general. Look at the James Webb Space Telescope: $9B so far, 17 years in development, and still its completion is uncertain. Its possible successors are even more grandiose and use the same outmoded designs. Look it ITER--how many billions and to what end?
Small science is excellent science. The problem is that politicians can relate to big projects but not to broad programs of smaller ones. And to keep them onboard, the big science acolytes have to cook up explanations that the politicians can use for their self-aggrandizement, such as "we're learning about the beginning of the universe." This problem is bigger than just the high-energy physics community.
I guess that it also will not tell us anything about how the universe has come into being naturally or how the universe has no need for a beginning after all.
ReplyDeleteA muon collider may be worth the money:
ReplyDeletehttps://arxiv.org/abs/1901.06150
The starting premise in this blog post is wrong. Breaking of electroweak symmetry is essential for formation of long-lived matter, hence creation of the observed universe. A major goal of collider physics is to study detailed properties of Higgs field(s) responsible for electroweak symmetry breaking. This has direct implications for the early history of the universe. See, e.g., Quigg and Shrock, arXiv:0901.3958.
ReplyDeleteFrom https://blogs.scientificamerican.com/observations/why-do-physicists-care-so-much-about-finding-the-higgs-boson/:
Quigg has written extensively on the consequences of a Higgs-free universe. He points out that when Salam and Weinberg were working out how the Higgs mechanism might help unify electromagnetism and the weak force, they realized that in addition to giving mass to the heavy force-carriers, the Higgs might also give mass to other fundamental particles.* The electron, therefore, would owe its mass to the Higgs field. Without that mass, electrons wouldn’t hook up with nuclei to form atoms. "That would mean no valence bonding, so much of chemistry, essentially all, would vanish," Quigg says. "Therefore no solid structures and no template for life."
Pavel,
DeleteThe "formation of long lived matter" is not the same as the "creation of the observed universe". It's manifestly false and I do not know why you would possibly make such a statement. Look up the word "universe" if you do not understand what I say. If particle physicists would replace "creation of universe" with "creation of long-lived matter", I would have no reason to complain.
Sabine,
DeleteI collegially agree with your first and last sentences. "Universe" can mean lots of things, especially the lowercase one. Until the word "universe" is universally defined to carry a very narrow meaning, I think it is possible to include "formation of long-lived matter" within the first microsecond after the Big Bang as a stage in the "formation of the observable universe" -- certainly so for a popular-science article.
Pavel,
DeleteWhat is your experience writing for the general public? I just checked your CV and it contains nothing.
So please allow me to draw on my experience writing for non-physicists for 12+ years. No one who doesn't already know what this sentence refers to would think that "creation of the universe" is supposed to mean "formation of long-lived matter sometime in the early universe and at densities 70 orders of magnitude below what we think the matter had at the big bang, in case there was a big bang".
This sentence is obviously PR speak. It is intended to mislead people. And the only reason I can think of that it passed the SciAm editor is that the editor themselves probably didn't know what this refers to, which is a problem in and by itself.
Go ask anyone in the street what they think "creation of the universe" means if you cannot follow.
Dear Sabine,
Delete...but this is a silly excuse, isn't it? You could do better. There is no universal agreement "in the street" about what "creation", "beginning", or "origin" of the "universe" means. Or else, you would have to write to Stephen Weinberg about the title of his "The First Three Minutes: A Modern View Of The Origin Of The Universe"; or tell David Christian that his "Origin Story: A Big History of Everything" must be super-careful to limit the origin of the universe to the first picosecond that a small group of cosmologists is concerned about.
I think, as a responsible blogger, you make a dedicated effort to minimize the possible misunderstandings that your omnifarious readership may have when interpreting your writings in the context of their preexisting backgrounds.
Maybe you could take a fresh look at this post and see what can be changed. In particular, the remark in bold is either wrong or not even wrong. I am guessing that this post can be partly traced to your valid critical remarks from ten years ago about the excessive references to "recreating the Big Bang" in the collider experiments that study the quark-gluon plasma. The quote that you criticize now, in the context in which it was presented and understood, does not refer to the quark-gluon plasma.
Pavel,
DeleteWhat I wrote is correct and it is obvious that you are trying to making excuses for your particle physics friends. The people whose books you mention certainly did not claim that the FCC can probe the origin of the universe, or else you must have misread their books.
I suggest you ask particle physicists to be more "responsible" with their writing and to avoid misunderstandings rather than complaining if I clarify what their advertisements really mean, thanks.
Dear Sabine,
Deletethe SciAm quote is carefully phrased and is consistent with the common view that creation/formation/beginning of the universe is a process that lasts, depending on its definition, between a fraction of a second to hundreds of thousands years:
"[P]article physics strives to push a diverse range of experimental approaches from which we may glean new answers to fundamental questions regarding the creation of the universe and the nature of the mysterious and elusive dark matter."
I am sorry that it does not conform to the definition of the "instantaneous creation" that you seem to wish everyone to follow.
Pavel,
DeleteThis has nothing to do with the time scale. I have already asked you this on facebook, but here we go once again. Please explain what you think a particle collider tells us about the creation of the universe. Look up the definition of "creation" if you do not know it. I have already posted this on facebook.
You are defending an indefensible position. The only reason I can think of why you would do this is that you actually believe that particle colliders can tell us how the universe was created. Please go and look at the facts. This is incorrect.
Dear Sabine,
DeleteI am afraid the statement
"The argument that large colliders can teach us anything about the beginning, origin, or creation of the universe is manifestly false."
is manifestly false. "Cosmology is a branch of astronomy concerned with the studies of the _origin_ and evolution of the universe, from the Big Bang to today and on into the future." [https://en.wikipedia.org/wiki/Cosmology] This is a common definition. The phrase "origin of something" is widely used in the scientific context (cf. Darwin), as well as the "beginning". Particle physics provides inputs to cosmological models of the period widely called "the origin of the observable universe".
Yes, I agree with you that the cosmology science prefers not to use "creation of the universe" to avoid sliding into metaphysics.
Pavel,
DeleteAre you now trying to tell us that particle physics is cosmology?
You also seem to mistake nuclear matter for the universe. These are not the same.
No, particle physics and cosmology aren't the same thing, and nuclear matter is not the same thing as the universe That's silly reductionism. The point is that many questions in particle physics are integral to cosmology. That's not even debatable, so what this post accomplishes is a mystery.
DeleteIs particle physics cosmology? Or maybe better asked is what is the relationship between elementary particles and cosmology? This is after all a facet of the unknown in quantum gravitation. Will the FCC tell us anything about that? I make no predictions with any certainty. If the sphaleron exists at the 10Tev range then maybe there is some cosmic-particle relationship we can study directly. I make no certain claim on this though.
DeleteWhen I see these repeated comments about more and more powerful accelerators it somewhat frustrating. I was for five years Chairman of the Road Development Authority and I never imagined any important people will lengthily discuss a multibillion dollar project in the absence of a detailed project proposal sufficiently detailed to make sense. Are we believing a decision to go ahead with a brand new collider will depend on what these article comments say. If not then either we have a brief proposal intelligently drafted so that everyone knows what is it that is intended.
ReplyDeleteAbed,
DeleteProposal is here. Google will bring up several shorter summaries in press releases/media reports.
Big Science now markets direct to the public. I guess we're supposed to let our elected representatives know that we want that big collider. Next will come appeals to national pride and "staying ahead" of the Chinese.
ReplyDeleteAgreed, and even worse, Big Science(BS) markets to politicians! What EU leader would want to miss out on the reflected glory from one of 'their' machines finally understanding the origin of the universe (yes politicians will simplify and exaggerate whatever they read even further).
DeleteIt's ironic that the FCC is being proposed on the 30th anniversary of the death of the SSC (superconducting super collider), which was stillborn after raging funding battles in Congress. I can only surmise that the FCC will face a similar fate, because congressional politics and big science are less and less on the same page these days and because international collaborations seem unlikely in the current isolationist climate. Even though HEP and other science funding is up, the price tag of the FCC is a special item that's likely to be DOA with so many agencies suggesting better ways to spend a single request of 20 - 30 billion.
ReplyDeleteWhat TeV is the FCC hoping to achieve? Is it really enough to significantly distinguish it from any existing colliders?
ReplyDeleteabout 100 in pp. That's about 6 times higher than the currently highest (hadron) collision energies, which is that of the LHC and about 14 TeV.
DeleteNobody believes that larger particle colliders mean a clear knowledge of the creation of the universe (of the big bang theory).
ReplyDeleteI think that people supporting >10TeV colliders are seeking a better understanding of physics at that energetic scales (supersymmetry, symmetry breaks, ...). It is also a question of who is leading scientific research (between China, USA and the EU).
Anyhow, I would think it twice before spending such a huge amount of money in supercolliders. Notice that Europe is already spending a lot of money in many huge scientific/technological (long term) projects at: ITER, ESA, ... and when you spend a lot of money, you want to see some return.
If nobody believes it then why do the authors of the article claim it does?
DeleteHello Sabine, I think that the authors wrote that phrase "regarding the creation of the universe" in the sense of what they write later: "the unknowns regarding dark matter, neutrino masses and the observed imbalance between matter and antimatter". Anyhow, I believe that the probability of discovering new fundamental physics at 100 TeV is pretty low.
ReplyDeleteAs a tax payer I want for each euro spent by the EU in science & technology to provide the widest possible return. But I have my concerns about: ITER, some ESA missions as eLISA and (of course) this FCC.
Well, of course th FCC will tell us about the creation of the universe, as the LHC already did... just watch Michio Kaku explaining it on Fox News :-) https://www.youtube.com/watch?v=2ivjsNmxs1E
ReplyDelete