The Higgs boson is not dangerous and will not destroy the universe.
The Higgs boson is a type of particle, a little ripple in the Higgs field. [See here for the Higgs FAQ.] This lowly particle, if you’re lucky enough to make one (and at the world’s largest particle accelerator, the Large Hadron Collider, only one in a trillion proton-proton collisions actually does so) has a brief life, disintegrating to other particles in less than the time that it takes light to cross from one side of an atom to another. (Recall that light can travel from the Earth to the Moon in under two seconds.) Such a fragile creature is hardly more dangerous than a mayfly.
Anyone who says otherwise probably read Hawking’s book (or read about it in the press) but didn’t understand what he or she was reading, perhaps because he or she had not read the Higgs FAQ.
If you want to worry about something Higgs-related, you can try to worry about the Higgs field, which is “ON” in our universe, though not nearly as “on” as it could be. If someone were to turn the Higgs field OFF, let’s say as a practical joke, that would be a disaster: all ordinary matter across the universe would explode, because the electrons on the outskirts of atoms would lose their mass and fly off into space. This is not something to worry about, however. We know it would require an input of energy and can’t happen spontaneously. Moreover, the amount of energy required to artificially turn the Higgs field off is immense; to do so even in a small room would require energy comparable to that of a typical supernova, an explosion of a star that can outshine an entire galaxy and releases the vast majority of its energy in unseen neutrinos. No one, fortunately, has a supernova in his or her back pocket. And if someone did, we’d have more immediate problems than worrying about someone wasting a supernova trying to turn off the Higgs field in a basement somewhere.
Now it would also be a disaster if someone could turn the Higgs field WAY UP… more than when your older brother turned up the volume on your stereo or MP3 player and blew out your speakers. In this case atoms would violently collapse, or worse, and things would be just as nasty as if the Higgs field were turned OFF. Should you worry about this? Well, it’s possible this could happen spontaneously, so it’s slightly more plausible. But I do mean slightly. Very slightly.
Recently, physicists have been writing about this possibility because if (a) you ASSUME that the types of particles that we’ve discovered so far are the only ones that affect the Higgs field, and (b) you ASSUME that there are no other important forces that affect the Higgs field other than the ones we know, then you can calculate, with some degree of reliability (though there is a debate about that degree) that (1) the Higgs field could lower the energy of the universe by suddenly jumping from ON to WAY WAY SUPER-DUPER ON, and (2) that the time we’d have to wait for it to do so spontaneously isn’t infinite. It would do this in two steps: first a bubble of WAY WAY ON Higgs field would form (via the curious ability of quantum mechanics to make the improbable happen, rarely), and then that bubble would expand and sweep across the universe, destroying everything in its path.
An aside: In particle physics lingo explained here, we say that “the universe has two possible ‘vacua’, the vacuum we live in, in which the Higgs field is ON a bit, and a second vacuum in which the Higgs field is HUGELY ON.” If the second vacuum has lower energy than the first, then the first vacuum is said to be “metastable”: although it lasts a very long time, it has a very small but non-zero probability of turning into the second vacuum someday. That’s because a bubble of the second vacuum that appears by chance inside the first vacuum will expand, and take over the whole universe.
Ok. First, should you buy the original assumptions? No. It’s just humans assuming that what we currently know is all there is to know; since when has that been true? Second, even if you do buy them, should you worry about the conclusion? No. The universe has existed in its current form for about 13.7 billion years. The Higgs field may not perform this nasty jump for trillions of years, or trillions of trillions, or trillions of trillions of trillions, or more. Likely more. In any case, nobody knows, but really, nobody should care very much. The calculation is hard, the answer highly uncertain, and worse, the whole thing is profoundly dependent on the ASSUMPTIONS. In fact, if the assumptions are slightly wrong — if there are other particles and forces that affect the Higgs field, or if there is more than one Higgs-like field in nature — then the calculation could end up being way off from the truth. Also possible is that the calculational method, which is subtle, isn’t yet refined enough to give the right answer. Altogether, this means that not only might the Higgs field’s nasty jump be much more or less likely than is currently believed, it might not even be possible at all. So we don’t actually know anything for sure, despite all the loose talk that suggests that we do. But in any case, since the universe has lived 13.7 billion years already, the chance is ridiculously tiny that this Higgs field jump, even if it is possible at all, will occur in your ultra-short 100 year-ish lifetime, or even that of any of your descendants.
What about the possibility that human beings could artificially cause the Higgs field to turn WAY WAY ON? Again, the amount of energy involved in trying to do that is extremely large — not a supernova, now, but far, far beyond current human capability, and likely impossible. (The technology required to build a particle accelerator with collisions at this energy, and the financial and environmental cost of running it, are more than a little difficult to imagine.) At this point we can barely make Higgs bosons — little ripples in the Higgs field; now you want to imagine us making a bubble where the Higgs field is WAY WAY WAY MORE ON than usual? We’re scientists, not magicians. And we deal in science — i.e., reality. Current and foreseeable technology cannot turn this imaginary possibility into reality.
Some dangers actually exist in reality. Asteroidlets do sometimes hit the earth; supernovas do explode, and a nearby one would be terrible; and you should not be wandering outdoors or in a shower during a lightning storm. As for the possible spontaneous destruction of the universe? Well, if it happens some day, it may have nothing to do with the Higgs field; it may very well be due to some other field, about which we currently know nothing, making a jump of a sort that we haven’t even learned about yet. Humans tend to assume that the things they know about are much scarier than they actually are (e.g. Yellowstone, the “super”-volcano) and that the things they don’t know about are much less scary than they actually are (e.g. what people used to think about ozone-destroying chemicals before they knew they destroyed ozone.) This is worth keeping in mind.
So anyone who tells you that we know that the universe is only “meta-stable”, and that someday the Higgs field will destroy it by suddenly screaming at the top of its lungs, or that we might cause it to do so, is forgetting to tell you about all the assumptions that went into that conclusion, and about the incredible energies required which may far exceed what humans can ever manage, and about the incredible lengths of time that may be involved, by which point there may be no more stars left to keep life going anyway, and possibly not even any more protons to make atoms out of. There’s a word for this kind of wild talk: “scare-mongering”. You can safely go back to sleep.
Or not. There’s plenty to keep you awake. But by comparison with the spread of the Ebola virus, the increasing carbon dioxide in the atmosphere and acidification of the oceans, or the accelerating loss of the world’s biodiversity, not to mention the greed and violence common in our species, worrying about Higgs bosons, or even the Higgs field in which a Higgs particle is a tiny ripple, seems to me a tempest in a top quark.