I'd suggest anyone with a passing knowledge of calculus, complex numbers, and vectors to sit through Leonard Suskind's lectures on quantum gravity. This one was good and wouldn't need the calc/math background, I think: https://www.youtube.com/watch?v=-OkwGDKoY0o . But YT is full of actual physics lectures and sitting in on them is pretty approachable with that calc/math background. I think they give an interesting comparison to these popular pieces on particle physics. You might not understand everything the way a physics college student should, and that's ok because you aren't one. But I bet you walk away knowing quite a bit more than you suspect and you can always replay them.
Pop-sci pieces tend to portray the universe as just a bunch of particles interacting in odd/spooky ways. It's a little reductive and sort of enshrines entanglement and similar concepts as unknowable at times. I skimmed this and it seems to spend a lot of time on spin 0 particles. Who knows, maybe that's a constraint from ER=EPR? But I didn't feel like it really conveys much about Higgs.
(Which would serve a purpose - "oh you can't know it so please come back for next installment in my series of 10 books describing it." I don't think any authors actually set out with that as a goal, explicitly, but they could do a better pointing out where to go for further, more complicated edification. That sort of thing could shoehorn new talent into science.)
Where is this series? The youtube link above seems to be to a standalone lecture. Trying the search terms from this discussion found two other standalone lectures. Is there some UI element on youtube that I'm missing that should make this obvious?
Searching for "leonard susskind lectures" returns a playlist as the first result for me (desktop web). There's also a UI element at the top to filter results to just playlists.
How do y'all organize your youtube queue, is there third party software? Looking to streamline this to make it "netflix easy" as I am inevitably feeling tired when allocating leisure time to this. I have a couch laptop, chromecast and iphone
It is not as simple as Netflix but my strategy is to add interesting videos into the "watch later" playlist. Then, during leisure time I do a quick scan and pick something.
If I find myself watching a lot of the same genre I create a "watch later" for that subject.
These are what originally got me into physics. For physics enthusiasts who have exhausted most pop physics content but aren't looking to get a full degree, there isn't much better than Susskind's lectures.
My journey with "serious" physics starts with his lectures (I was curious what I needed to know to be able to render my own black holes like in interstellar).
The discovery of the Higss boson and nothing else outside the Standard Model at the LHC is the worst-case scenario: we now have a theory of everything that predicts nothing...
The standard model is basically a list of correctly working theories, taped together like the monster of Frankenstein.
Nobody likes it. It's ugly as hell. Physicists, dreaming of some perfect symmetry driving the universe forwards all recoil in horror. Everybody thinks ot must be possible to make something better.
Problem is, the monster works. After tuning a short list of parameters, it survives everything we can throw at it. We have trouble calculating the consequences, but that's not a failing of the model
This a a pretty reaching take. The standard model has lots of short comings and definitely doesn't survive everything we throw at it, namely gravity and likewise general relativity.
If vacuum is meta-stable it is possible for entirely different set of fields to exist instead, but the gravity would be the same, I guess. This makes it outside of standard model.
It predicts things we’ve already observed, sure. But we came up with the standard model after seeing what ideas worked and which ones didn’t, and we get to amend it every time an experiment shows us something new.
The standard model isn’t some single theory that was devised and survived testing. It’s an amalgam of various ideas which have survived experimental verification. It’s a bit hollow IMO to say it “predicts” things. It’s a bit like drawing the dartboard after throwing the darts.
It predicts much more than what has been put in. The SM has 22 free parameters. I agree that if it predicted exactly 22 data points it'd be a pointless encoding of what was put in. But it predicts thousands and thousands of data points, some to twelve decimal points.
It predicts things as-yet-unseen, also, such as detailed proton structure, precision atomic matrix elements, detailed nuclear structure and decay rates, and so on.
Neutrinos were predicted and discovered long before the standard model.
Note that the standard model did NOT predict neutrino mass. Though it did predict that neutrino mass would explain the shortfall of observed neutrinos from the Sun.
The standard model is far from a 'theory of everything'. To name but a few problems:
* gravity
* massive neutrinos
* dark matter
* dark energy
It is also a highly parameterised model tuned to fit the data.
The biggest concern is whether we can realistically probe the failings of the standard model using a collider at ~TeV scale? If that is the case, then the standard model may be the best model of particle physics we will ever achieve.
But yeah, I agree that the "highly parameterized" part is a statement from fashion, and the number of parameters is really not a good reason to try to replace the Standard Model. (There are many good reasons, but this one isn't one of them.)
Also, I am yet to see any alternative proposal with fewer parameters.
There is a philosophical discussion to be had about whether 19 physical parameters is "a lot", and another discussion about fine tuning. However, I was primarily referring to the artifical parameters that arise from doing real calculations (renormalisation scale, mass factorisation scale, PDFs etc). These plague pretty much all perturbative QCD calculations, and then particle physicists play games like varying them by a factor of 1/2 and 2 to get something that looks like error bars...
The number of SM parameters is not a lot, given the reach of the model, which is literally every physical phenomenon ever observed on Earth with enough detail, but gravity. Thousands of independent experiments, and observational data on a scale so absurdly large it's hard to state plainly. Any philosopher who wants to claim nineteen parameters is large is out of their minds!
Fine tuning, I agree, is a philosophical issue. I'm a physicist, and I don't buy it. Why does everything have to be perturbatively pleasant? Nobody promised us that.
The issue of artificial parameters is a red herring, I think. Properly computed, of course, well-defined observables are renormalization scale independent. You might have to pick a scheme/scale to do the calculation, but whatever scale dependence remains is an indication of some perturbative truncation. The continuum limit of LQCD, for example, produces real observables with no renormalization scale dependence. Hell, renormalization is not even mysterious in a computational approach.
> The standard model is far from a 'theory of everything'. To name but a few problems...
You missed a bit of detail: Reality, and The Hard Problem of Consciousness.
Granted, this is often not a popular topic of discussion (if not ~taboo), but it's actually rather important imho.
The best thing I've ever come across that illustrates the gap/difference between how materialists think about reality vs (some) "non-materialists" (in this case Tibetan Buddhist Alan Wallace) is this video....seeing the way two highly competent but very different thinkers approach the problem space is enlightening, although it might require some background in both domains to appreciate (so Alan's case doesn't appear as "woo woo").
The Nature of Reality: A Dialogue Between a Buddhist Scholar and a Theoretical Physicist (Sean Carroll)
I think you have it exactly backwards. The standard model is astonishingly good at predictions. It's just not a theory of everything. And the output from LHC has discounted some approaches to a TofE but hasn't helped to point the way to a strong candidate.
From my understanding (/me not a physicist), it is rare. It's created only in high-energy situations, and decays extremely quickly. In the very beginning, there were a lot of them, but not for long.
I gleaned from the article that the field is everywhere; I think it's correct to say that all fields are everywhere, but according to the article the Higgs field is distinctive: "The Higgs field has a nonzero vacuum expectation value throughout all of spacetime, meaning there is always some value associated with it, even when no Higgs particles are present."
I guess, FSVO "present". If there were no Higgs particles anywhere, would the Higgs field disappear? I have no idea.
There are two equivalent ways to represent the universe:
1) The average value of the Higgs field is zero and there is a HUGE amount of Higgs bosons everywhere, but all the calculations are horribly^1000000 difficult.
2) The average value of the Higgs field is a constant that is not zero and there are very few Higgs bosons here and there, and the calculations are easy [1].
Obviously physicist prefer the second description, in spite both are equivalent.
There are some technical problems if you imagine that there is a constant everywhere in the universe, and has exactly the same value [2]. So the solution is that it has the "constant" has an average value and allow local variations. The local variations are the Higgs bosons, because the field is quantized.
In a universe where the average value of the Higgs boson is not zero, but there are no Higgs bosons, you get the same technical problems that were solved with the idea of Higgs.
[1] It's easy if you have a PhD in physics, a few years of specialization. I can't do them, but I know people that can.
[2] There are other constants anyway, but they are different... I have no better way to explain it :(.
...which is counterfactual, if you mean "anywhere in spacetime", because there were a lot of Higgs particles, at the very beginning; and those particles exist in spacetime. If there are no Higgs particles in spacetime, that's a different Universe. I guess (/me not a physicist).
This is a good summary. Only thing to add is that the Higgs particles are basically oscillations on top of the background value of the Higgs field, just like photons are oscillations of an EM field. In both cases, the field is the more fundamental object, so your question at the end is backwards :)
Those fields are a mathematical tool to describe what is going on in a specific way - for example making the local character of particle interactions obvious - but there is no evidence that there are actually any fields. Quite the opposite, a good reason to doubt that those fields are real is that they have Gauge redundancies, i.e. one physical state has several different mathematical representations.
So basically a certain energy allows to bring forth certain particles into being through laws of physics. How does the universe know the laws, how is it encoded? Sorry if I am vague!
The universe simply is, and “laws” is what we know about what/how it is. For example, the law: “Things consist of atoms.” The universe does not “know” this law, we do.
Interesting article, I think I actually understand a lot more than I usually do with physics articles. This quote stood out though. I lol’d:
“The Higgs field, on the other hand, is just as spinless as the Higgs boson. Like a college senior sitting forlorn in a career counselor’s office, it has no direction”.
Pop-sci pieces tend to portray the universe as just a bunch of particles interacting in odd/spooky ways. It's a little reductive and sort of enshrines entanglement and similar concepts as unknowable at times. I skimmed this and it seems to spend a lot of time on spin 0 particles. Who knows, maybe that's a constraint from ER=EPR? But I didn't feel like it really conveys much about Higgs.
(Which would serve a purpose - "oh you can't know it so please come back for next installment in my series of 10 books describing it." I don't think any authors actually set out with that as a goal, explicitly, but they could do a better pointing out where to go for further, more complicated edification. That sort of thing could shoehorn new talent into science.)