So I got the following questions from a high school English teacher this morning, and I thought, for fun, I’d put the answers here for you to enjoy. Here (slightly abridged) is what the teacher wrote, and my answers:
I’ve turned my classroom into a video game to increase student engagement. In my gamified classroom, the villain is experimenting with/on the Higgs field. Your article on what would happen if the Higgs field was turned off answered a lot of my questions, but … I was hoping you could answer a couple of questions for me. I am sure these questions probably don’t have “real” answers, and are completely ridiculous, but I’d love to hear from you.
1. I’ve gathered from your site, and others like it, that turning off the Higgs field and making particles mass-less isn’t possible.
- That’s correct. The Higgs field‘s non-zero average value is held in place by interactions of the field with itself and with other fields, and it takes an enormous amount of energy to change it. That’s reflected in the fact that the Higgs particle (i.e. Higgs boson) has a large mass compared to the particles that predominantly make up ordinary matter: electrons and up and down quarks. Even to turn off the Higgs field for an instant in your classroom alone would require taking all the energy of a supernova (the largest type of explosion we regularly observe in the universe, in which a big star blows itself to pieces), and focusing it into that one room. On top of that, it’s not enough just to have the energy; you have to find a way to make it do what you want, and that would be extremely difficult to achieve in this case. But let’s ignore that complication; we’ve got plenty of problems already.
If it were, how might my villain try to do that? What he shoot it the field with protons, or smash two Higgs bosons together? How would one try to turn off a field?
- Um, that’s a tough one. Shooting the field with protons, or smashing Higgs particles together, couldn’t change the Higgs field appreciably any more than shooting bullets into the sea, or smashing big ocean waves together, could boil away the oceans. [That’s not meant as a close analogy, but it gives the rough intuition.]
- Imagining something even semi-realistic is nigh impossible. To turn off the Higgs field across the entire earth and its vicinity would force our villain to get all the stars in our galaxy, and all of the galaxies anywhere nearby, to simultaneously explode, and to then direct their energy entirely to the earth. And then, that’s just enough to turn the Higgs field off for an instant. To turn it off and keep it off would require even more energy… Meanwhile, just the arrival of all that energy beamed at the earth would vaporize the planet even before the Higgs field turned off!
- Perhaps your villain has discovered that the universe was built by and is controlled by a supercomputer, itself created by a species of intelligent creatures that lives in a different universe; and your villain has hacked into the computer and has figured out how to use it to turn off the Higgs field without needing to gather any energy at all. Unbelievable as this scenario is, at least it allows you to imagine evading the known laws of physics without apology. Anything that I can think of that obeys those laws seems just as crazy!
2. In your article you said a world with no Higgs field would be uninhabitable. If it were, in theory, what would a world with no Higgs field be like? Would people float away? Get turned inside out? Would we all be crushed? I want to paint a picture of what would happen to the world if the villain were successful in turning off the Higgs field while we were on Earth.
- Oh no, it’s much worse than just having an uninhabitable planet. There’d be nothing around here except elementary particles. With the Higgs field turned off, all atoms in the Higgs field-less region would instantly explode! The size of an atom increases as the mass of the electron decreases; turn off the electron mass, which would drop to zero if the Higgs field were turned off, and atoms would just fall apart. Of course all physical materials are made from atoms — and all chemistry and biology is based on atoms — so there’d be no earth or people left. Just a very big BOOM! How big? The disintegration of the earth’s atoms would release roughly enough energy to heat everything in and on the earth instantly to something like 10,000 degrees. Actually it is probably a lot worse than this. More subtle effects on the nuclei of atoms would probably result in a temperature close to 1,000,000,000,000 degrees — quite a bit hotter than the interior of the sun. So imagine turning the earth into something as hot as the sun, even for a few moments. There’s not much point in discussing the details of what happens to human bodies; just like the rocks and the oceans and the air, we’d all be totally and instantaneously disintegrated into our constituent subatomic particles. You know what people say about wanting to“become one with the Earth” — well, this is more like “becoming bazillions with the Earth”…
3. Is there any possibility that the Higgs boson/field, and the future advances in science that comes with it, might one day lead to a new energy source? Similar to a Nuclear plant, could one day we collide two Higgs bosons together for energy?
- It’s very difficult to predict the future; the first person who created radio waves didn’t see any use for them, and the first people who thought about nuclear fusion (the source of energy in the sun) were confident it would never be considered potentially useful on earth. So I’ll be cautious here. Still, most experts (including me) would guess that the answer is that we won’t get a new energy source, at least not in any direct way. You can get energy if you have it stored somewhere and you can release it, but (for the reasons just discussed) you have to put energy in to make the Higgs field do something other than just sit there, and there’s no known or imaginable way to draw energy from it. Certainly we won’t collide Higgs particle together for energy; it takes lots of energy to make them, they last only a tiny tiny tiny fraction of a second, and whatever energy is released in their collisions or decays will be less than you put in. [This is in contrast to coal or gasoline or atomic nuclei, which are just found lying around, waiting for us to find ways to release their stored energy by burning the coal or gas, or breaking apart the nuclei.] But there could, of course, be indirect impacts. Perhaps what we learn from the Higgs boson will in turn allow us to discover some other source of stored energy… ahhh, fine, but now we’re just speculating wildly.
- So if you want to speculate wildly, here’s a way. Suppose it turns out that dark matter has energy stored in it that it gradually releases, and that what we learn from the studies of the Higgs boson indirectly teaches us where to detect clumps of dark matter in distant orbits around the sun; then you can imagine we might someday put space stations near those clumps that power themselves off of the energy that the dark matter is slowly emitting from its storehouse. Almost totally unbelievable. But you’re making up a game. Go for it.
31 Responses
A follow up question from a lay person if I may:
How do we know, or why do we believe, that the Higgs field is uniform at very large scale?
Is it possible that electrons gigaparsecs away may have a slightly different mass than those near earth?
BYW: I want to thank you for your excellent explanations of particle decay and electron spin. 🙂
See this post: http://profmattstrassler.com/2012/12/18/the-constancy-of-the-heavens-verified-anew/
While the mechanism for turning off the Higgs field is unknown/doesn’t exist you mentioned scales of energies needed to disable it for fairly large regions like a class room or the earth. If it was restricted to a region that was much smaller, i.e. a cubic planck length or the ‘volume’ of a quark or other particle. Would these energy amounts even be within the realm of possibility?
Nice post, Bravo also to the teacher and her/his students to open the door to a fantastic odyssey in Higgs technology or could I say zeptotechnology ?! To paraphrase Feynman :
There is plenty of fun and imagination at the high school level 😉
As far as zeptotechnology is concerned, similar questions have also been asked at Physics.Stack.Exchange with at least one simple answer : crudely speaking: zeptotechnology = teraelectronvolt energy= petakelvin temperature
(http://physics.stackexchange.com/questions/55468/is-it-possible-to-remove-the-higgs-field-from-an-object-to-make-it-have-no-mass).
Of course, it could be there is a finer answer once the naturalness issue raised by the Higgs boson without supersymmetric particles at zeptoscale is better understood but could it be a high-school teacher hypothesis ?.Who knows…
This video game controversy was very educational for many of us!!
Do I understand that no matter what happens to Higgs field, baryon masses will remain about same or am I reading too much into this? Of course that will be disaster for the universe in any case!
You actually have to calculate carefully and decide what you are holding fixed. I haven’t checked this in a while, but I believe you find — accounting for several different effects — that the proton and neutron masses drop by about 1/2. But to prove this is not trivial. I plan to write an article about it, but the ones I’m writing now have to come first, along with an article about how the proton mass gets set in the first place.
I know the guy who asked you this question. I also work in science communication in DC. I wanted to thank you for answering his question in such an enlightening and creative way and for devoting some of your time to public education around your work. It’s incredibly valuable. For his purposes, I really like your “simulation” idea.
Give me a false premise and a place to stand, and I can prove the world.
Hello!
Teacher in question here!
I’d like to thank everyone, especially Professor Strassler, for taking the time to respond to my completely ridiculous questions. This was way more than I ever expected.
It’ll probably take me days to even begin to understand the high level science here, but I can’t wait to try. This discussion will go a long way to help me fill in the plot holes in my game.
My students and I thank you!
Chris Aviles
http://www.techedupteacher.com
You’re welcome. I viewed it as an opportunity to engage a wider audience in the enormously large and small numbers that come up in particle physics, and in how flimsy ordinary matter is compared to the powerful forces of nature. I’m writing about even larger numbers right now…
Your students are indeed fortunate to have such a thoughtful and innovative teacher as you. Many, if not most, are content to conform to a uninspired curriculum that fails *miserably* to keep pace with current trends, especially within the sciences. Kudos to you, Mr. Aviles. You Sir, are special.
Postscript to Matt: Where do you find the time? And the energy? I am simply awed by you.
Time is the hard part. I get my energy from the Higgs field.
Actually, Matt, most of your energy comes from the QCD condensate….it’s mostly nucleons.
Of course; I always make this point very clearly in public talks and articles, see for example http://profmattstrassler.com/2013/03/20/why-the-higgs-matters-in-a-few-sentences/ , http://profmattstrassler.com/2012/10/15/why-the-higgs-and-gravity-are-unrelated/ , http://profmattstrassler.com/articles-and-posts/the-higgs-particle/why-the-higgs-particle-matters/ , http://grassrootstv.org/Show.aspx?ShowID=11527
However, if you calculate carefully — and this is a point I don’t make often, and I haven’t yet got enough stuff on this website to explain it properly to the public — actually the QCD condensate scale goes down by about a factor of close to 2 if you set the Higgs field’s value to zero. It’s purely an accident that it’s a factor of 2 rather than a factor of 10 or 1.3 — it’s a consequence of the way the strength of the strong nuclear force is changed when the top and bottom and charm quarks lose their large masses.
People!
Matt refers above to a talk he gave, link here:
http://grassrootstv.org/Show.aspx?ShowID=11527
It’s an absolute GEM. I watched it twice. Don’t miss it.
As a former high school physics teacher, I appreciate the questions and answers. I wouldn’t have expected these from an english teacher, though. I’m glad to see them regardless of the source.
Thanks, Matt.
wow!! I like that professor already!!! and of course, you played nicely Dr. Strassler 🙂
I second the proposal of Marc Sher — a conceivable scenario for a video game could be based on the false vacuum assumption (which is not a part of the Standard Model, but could be true in principle). You can read some details about it on Wikipedia:
http://en.wikipedia.org/wiki/False_vacuum
Basically, the assumption is that the Higgs field is in the metastable vacuum — the “false” minimum on the diagram in the Wikipedia article. By concentrating enough energy in some critical volume, the evil scientist could raise the energy of the Higgs field above the maximum between the “true” and “false” minima. If that happens, the Higgs field would drop back into the “true”, lower minimum with very high probability (instead of going back to the “false” one). If the evil scientist makes this happen in some volume of critical size (called the “bubble”), he would start a chain reaction of sorts — the bubble would start to expand in all directions, with the speed of light and no way to stop it.
The effect of the bubble on matter is twofold. In short-term, as the matter crosses the boundary and enters the bubble, it would be heated up to enormous temperature — all atoms would be completely ionized into plasma (or maybe even quark-gluon plasma if the energy output is high enough). The expansion of the bubble happens with the enormous release of energy (the “true” vacuum has lower energy than the “false” vacuum, and this energy difference gets released from every point of space within the bubble — or something to that extent). Therefore, in short term, the Earth would be instantly destroyed, the Sun within 8 minutes, and the Solar system after a couple of hours or so. The bubble expands with the speed of light, so it would take some time to reach other stars, and you’d have to wait quite a long time for it to engulf our galaxy, not to mention reach other galaxies.
In the long-term, the plasma created from the Earth, Sun and other planets would eventually cool down and form a new Solar system, with matter settling down into atoms etc, as usual. Laws of physics would be actually quite similar to what they were before — the only difference would be that everything would be proportionally “lighter”, i.e. everything would have smaller mass. From the perspective of the creatures that would maybe eventually evolve on the “new” planet Earth, the laws of physics would be the same as they appear to us. The only difference they would see is that gravity is much weaker. In particular, they would be able to observe that the gravitational constant appears to be smaller in their Solar system then in other places in the Universe. In addition, they could track the expansion of the bubble, whose boundary would induce large explosions of stars as they enter the bubble.
When you think about it, the evil scientist might have a typical Hollywood motivation — the current world is too “bad”, and he wants to destroy everything and let our Solar system start from a blank slate. While at it, it would be convenient to reduce the strength of gravitation along the way, so that it would be easier for the eventual new intelligent races to travel into space and explore the Solar system. It’s all for a noble cause, in the end… 😉
In order to achieve his goal, the evil scientist would need a carefully crafted, and most importantly VERY BIG particle accelerator, which would be able to concentrate the energy necessary to excite the Higgs field beyond the local maximum within the critical bubble. That would take quite a lot of energy, but could be doable in principle (given enough resources). The accelerator ring would most probably have to be in the orbit around the Sun, and powered by nuclear fusion, solar energy, and anything else available. The fuel for fusion could come from the “ice” planets like Jupiter’s Europa, Uranus, Neptun, etc., where one could find hydrogen in large quantities.
If the evil scientist has enough resources to build all that, only James Bond could save the Earth from imminent — and the Universe from a long-term — destruction… 😉
HTH, 🙂
Marko
Marko — although the basic notion you list here is largely reasonable, I believe you have made a few significant errors.
You say : “In the long-term, the plasma created from the Earth, Sun and other planets would eventually cool down and form a new Solar system, with matter settling down into atoms etc, as usual. Laws of physics would be actually quite similar to what they were before — the only difference would be that everything would be proportionally “lighter”, i.e. everything would have smaller mass. ”
I am afraid this is profoundly wrong, in at least three senses that I can think of at the moment.
First, unless there are other fields playing a significant role, we know the potential for the Higgs at small values of the Higgs mass in the Standard Model (or anything sufficiently similar) so after the transition, the Higgs field’s expectation value will be larger, and typically much, much larger. If there are indeed other fields, then we have to consider their effects upon the world, which might be significant.
Second, your statement that everything will be proportionally lighter (or heavier) is wrong. Proton and neutron masses will not proportionally decrease or increase because their masses are not proportional to the Higgs expectation value. This is the largest effect among several subtleties with the notion that everything will be proportionally lighter or heavier. Another subtlety is that the pion mass will shift like the square root of the Higgs field, and that has a non-trivial effect on nuclear physics. Even if there are atoms, the relative changes in the electron mass and the nuclear masses will have significant effects on chemistry.
Third, with the change in the various masses away from strict proportionality, it isn’t clear which nuclei will still be stable; we can’t calculate this reliably. Certainly there will be major changes, and the triple alpha resonance which is crucial for carbon formation may not occur. There may only be hydrogen after this shift, and so there may be no rocky planets. Nuclear physics will certainly be different and the sun may not resemble what it does today.
Finally, I think you will not be able to do this even with a big accelerator. The probability of getting a critical bubble of sufficient size from a pointlike ultra-high-energy collision is extremely small. You need something more dramatic than this, in order to obtain a sufficiently large bubble. This is what Marc Sher alluded to.
In any case, though, the teacher asked about turning the Higgs field off — so I answered that question. The question of getting the Higgs field to shift to another non-zero value is different. What I logically left out was the possibility that you could turn off the Higgs field while turning on something else — i.e., a non-minimal model of scalar fields — at which point we have no idea what would happen after the transition occurred. But, as you and Marc are suggesting, perhaps I should add this possibility in.
Ok, let’s assume the simplest possible scenario — the ordinary SM minimally coupled to Einstein-Hilbert gravity, with the Higgs potential as in the diagram on the Wikipedia article I quoted. Therefore, no extra fields or any other exotica. In that case…
“we know the potential for the Higgs at small values of the Higgs mass in the Standard Model (or anything sufficiently similar) so after the transition, the Higgs field’s expectation value will be larger”
What we know is the neighbourhood around the “false” minimum of the potential in the picture. The “true” minimum can be either on the left (smaller vev, as in the picture) or on the right (larger vev, not depicted). You seem to claim that the true minimum must be on the right of the false one, so that it has a larger vev. In other words, the potential from the picture is forbidden for some reason, and only its “mirror-image” is allowed. Why must that be? (I’m not arguing against your statement, I just don’t see why…)
“Proton and neutron masses will not proportionally decrease or increase because their masses are not proportional to the Higgs expectation value.”
I think they must be proportional, on purely dimensional-analysis grounds. The only pieces of the SM Lagrangian that are not conformally invariant are the Higgs mass/vev, and the gravitational constant. Moreover, you can express the Higgs mass/vev as proportional to the Planck mass, which is then the only dimensionful parameter in the theory. After changing the vev from the false to the true one, you can always multiply the whole Lagrangian with an appropriate constant (this is unobservable!) to rescale back the vev to its “false” value. The constant can be reabsorbed everywhere else by rescaling the fields, and due to conformal invariance the whole matter-part of the Lagrangian will look the same as it was in the “false” case. The only thing which will rescale observably is the gravitational constant. After these transformations (try it out?), you end up with the original Lagrangian, with the only change being in the value of G. Consequently, all nongravitational predictions remain the same. So am I missing something?
“Third, with the change in the various masses away from strict proportionality…”
This relies on me being wrong somewhere in the dimensional analysis above. 🙂
“Finally, I think you will not be able to do this even with a big accelerator.”
This is most probably true, I guess. But hey, we are discussing a video-game here. Moreover, mere laws of physics never stopped James Bond before… 😀
“In any case, though, the teacher asked about turning the Higgs field off — so I answered that question.”
Sure, your answer was very complete, nothing to add there. It’s just that Marc inspired me to discuss a somewhat alternative scenario, which sounds more interesting… 😉
Best, 🙂
Marko
1) We know there’s no minimum at smaller values of the Higgs field’s value because of renormalizability of the Standard Model. To get what you’re suggesting (in particular, to have a potential like the one in the Wikipedia article) there would have to be a immense Higgs^6 interaction along with the Higgs^2 and Higgs^4 interactions of the Standard Model. This is surely not allowed by the excellent agreement of the Standard Model with data.
Beyond the Standard Model, where there might be additional scalar fields, you could modify this, because then there are other terms in the potential and the possibility of additional minima. But not within the Standard Model.
2,3) Your dimensional analysis is profoundly wrong, because you’re leaving out one of the most important discoveries of the 20th century… so it is good that you’re getting a chance to learn about that now. You need to study “dimensional transmutation” and “asymptotic freedom”. As applied to quarks and gluons, you need to read Politzer and Gross & Wilczek 1973, Nobel Prize 2004, who were following people like Callan and Symanzik, who in turn were following Wilson and Kadanoff, who were the people who most deeply understood how quantum field theory works. The scale-invariance you are trying to use is true classically, but it is not true quantum mechanically; and if this weren’t true, there’d be no “confinement” of quarks, no protons, and no atomic nuclei. [This failure of scale invariance is often called a “scale anomaly”.] The proton mass (along with the mass of most hadrons) is set not by the Higgs field but by the scale of confinement, in turn set by dimensional transmutation. If you turned the Higgs field off completely, the proton would NOT be massless (you can check this in both toy theoretical examples and in computer simulations of QCD with varying quark masses). Similarly, although the pion would be massless, it is a famous calculation of the 1970s that its mass is not proportional to the quark masses and the Higgs field but to their square root, thus again violating dimensional analysis. See equation 1 of http://cds.cern.ch/record/295740/files/9602240.pdf, for instance.
If you want the proton mass to scale the same way as the Higgs field’s value, you have to adjust the strength of the strong nuclear force up at the Planck scale at the same time as you change the Higgs field. The strength of this force is conceptually and technically independent of the Higgs potential, so this adjustment definitely would not happen automatically when the Higgs field tunnels to a new vacuum.
1) Ok, I wasn’t aware of this, I didn’t really study those ways of modifying the Higgs sector. And again Wikipedia tripped me over… 🙂
2,3) You won’t believe me, but as soon as I hit the “post comment” button I remembered about the conformal anomaly… My QFT-fu apparently stops working after midnight… 😉
So yes, you’re right, proton mass will not scale along with the Higgs vev. I got carried away with the classical picture, sorry. 🙂
Best, 🙂
Marko
All good things to learn… particle physics is full of fabulous subtleties that are very much relevant to our very existence and which determine the essential details of our world.
Suppose for a moment that a black hole is not a singularity. I cannot agree with the idea of matter collecting into one point without growing larger into something so gravitationly strong that it could not help but eat the entire universe. I predicted years ago that a black hole is at the center of each galaxy. That is why the galaxy is there.
The universe is expanding, not shrinking. Suppose that a black hole is a point is space that has punched through to somewhere else. Either in our universe or some other point in the multiverse. Such gravity would shred atoms into their lesser parts. Protons and neutrons pulled in and torn apart. (dark matter) electrons released as photons (dark energy).
If there is matter on the other side of this point, collisions occur and a star is born. If empty space? A collection of dark matter, which begins to seek itself out to begin rebuilding atoms due to the Higgs force. Your thoughts please.
LT Roberts
Entertaining questions and answers! I read recently about a speculation that the potential energy curve may have a lower minimum than the one in which Higgs field is sitting now. Then it can tunnel to the lower minimum. That would be a nice way to end the universe or a game!! What do you think of that?
This is not a new speculation; ideas like this go back at least as far as the 1970s and probably much earlier. Sure, we can consider this; but can we turn *off* the Higgs field in this way? You have to make the theory more complicated if that’s what you want to do… but maybe that should have been my answer.
Of course, if we live in a metastable vacuum, then a collision of high enough energy could touch off the transition (as cosmic rays do in a bubble chamber). I looked at this once in a paper with Ellis and Linde. Just having enough energy isn’t enough — there is a minimum size for a critical bubble, and the energy of the collision must thermalize throughout that region. It’s quite complicated.
Naturally, the LHC is not a danger because cosmic rays of much higher energy hit the earth quite often, and we are still here.
True, but this would not result in the Higgs field turning off (we know the potential energy well enough to know that) unless there’s some other field that turns on in a big way. And that could change the universe so much we have no idea what would happen after. I felt, therefore, that this was not in the spirit of the teacher’s question. But you’re right, I could have taken that route instead.
Marc – out of curiousity, can one simply estimate what, parametrically, would be the size of a critical bubble in a simple model where you have a singlet scalar and a doublet scalar, with one minimum where the doublet is zero and the singlet has a value v, and another minimum where the doublet has a value v and the singlet is zero?
Matt–a brief answer is “no”. One needs to know the shape of the potential (in this case 2-field) between the minima, and you don’t give that. Given the shape, one can solve the bounce equations and calculate the critical bubble radius. It’s messy, but doable, but certainly not simple. In many inflationary models (and the SM), the potential, to a good approximation is – lambda phi^4 for which there is an analytic solution. But with two fields, it is a lot messier.