I know you’re all following the Minute Physics videos (that we talked about here), but just in case my knowledge is somehow fallible you really should start following them. After taking care of why stones are round, and why there is no pink light, Henry Reich is now explaining the fundamental nature of our everyday world: quantum field theory and the Standard Model. It’s a multi-part series, since some things deserve more than a minute, dammit.
Two parts have been posted so far. The first is just an intro, pointing out something we’ve already heard: the Standard Model of Particle physics describes all the world we experience in our everyday lives.
The second one, just up, tackles quantum field theory and the Pauli exclusion principle, of which we’ve been recently speaking. (Admittedly it’s two minutes long, but these are big topics!)
The world is made of fields, which appear to us as particles when we look at them. Something everyone should know.
You say the Standard Model of Particle physics describes all the world we experience in our everyday lives, yet I see nothing in this model which accounts for the strange dream I had last night, in which I descended the nine circles of hell and sat upon a throne of skulls, nor Muslims rioting over burning books in Afghanistan, nor the haunting gaze of an owl at midnight, nor much else that makes up a typical day of this thing some call “reality.” I’m therefore calling utter bullshit on your standard model, Mr. physicist!
Thank you, very accessible. It would be nice to also shed light on the Lagrangian, and how it’s a ‘modest’ attempt at looking at the world under the framework of classical mechanics (Newton). To what extent is locality (co-ordinate physics, in a loose sense) a restriction when one attempts to analyze the global aspects of a system? For example, can we derive a ‘massless’ (scalar) gauge theory? For example, all finite energy field configurations approach vacuum at infinity. If asymptotic values cannot change, how are topological currents conserved at finite energy continuous fields?
I guess the main question would force us to study Arnold’s conjecture (Liouville’s theorem) more closely. On my phone, apologies for lack of clearness. I’m only slightly dissatisfied with Darboux’s interpretations.
I think Henry Reich`s Minute Physics are the most ingenious videos I have seen for those that are interested in getting into physics on a beginner level. I have been following them since he started them. I have just have to register my displeasure of interjecting Jesus as a historical figure when there is no archaeological evidence or scientific evidence to back this up. The American Institute of Archaeology and famous secular archaeologists like Katherina Galor and Dr. Robert R. Cargill have written papers illustrating this concept. Even if you dismiss the historical Jesus as a religious figure, it is questionable that he existed to have any electrons. I am not offended but considering the historical options available for a scientific video, I just find the choice extremely weird. However, kudos to the Minute Physics and I hope Henry continues to produce them for years to come.
The quantum field video is brilliant, but I think he goes too far when he compares electrons to 3s. It is sometimes (not always) possible to assign a classical trajectory to an electron, and hence to say that this electron, here, is the same electron that was over there, then. For atoms, this situation is even more common. So I think it actually is meaningful to say that you’re now inhaling some of the same molecules that Caesar exhaled in his dying breath.
“the Standard Model of Particle physics describes all the world we experience in our everyday lives.” Err, since then does the Standard Model of Particle physics include gravity…? 😉
I HATE these explanations.
Wtf is a field? How am I supposed to know this if I don’t already know the content that this video purports to explain?
And how do I “summon particles” from anything? I’m pretty sure this is an ability I don’t have.
So now that matter is defined in terms of two things that make no sense (fields and summoning), how am I better off than I was before? In the end they just tell us that matter is anything that takes up space, which is probably the most useful piece of information in the entire video.
“The Standard Model of Particle physics describes all the world we experience in our everyday lives.”
If by “we” you mean particle physicists, but in that case you should get out more 😛
Quantum Field Theory is the most beautiful and fundamental aspect of our knowledge about the physical world and I’ve always struggled with why, as far as public understanding goes- it’s nature’s best kept secret!
>>“the Standard Model of Particle physics describes all the world we experience in our >>everyday lives.” Err, since then does the Standard Model of Particle physics include >>gravity…? 😉
Exactly. I threw a stone up in the air and it came back and hit the ground; also my daughter recently built a pendulum for her science class. Two simple, everyday things not explainable by the Standard Model.
#5, Bjoern.
The Standard Model of Particle Physics do contain the three forces, gravity, electroweak forces and the strong force.
This is a perfect poster: http://www.pha.jhu.edu/~dfehling/particle.gif
Thomas, look at that chart more carefully: “Gravity is included on this chart because it is one of the fundamental interactions even though not part of the ‘Standard Model’.”
There currently exists no accepted particle theory of gravity.
M
Mr. Carroll is there any experimental evidence for the existence of fields as primary as opposed to particles. Much as I love QFT I can’t help but feel that they refer to unobservable entities as opposed to the particle tracks we actually observe in high energy experiments. Every QFT text states as you have that fields are the “real” things and particles simply manifestations of them but give no evidence to back up this statement. Granted the theoretical predictions are impressive but that doesn’t rule out a fundamental theory of particles (or strings) that at large distances (many planck lengths) resembles a field theory.
@ Mark Weitzman,
If I may add my two cents, one thing I can think of is the fact that I can collide two protons together at high energy (well, not me, but particle physicists can at the LHC) and make a variety of particles, such as the Higgs boson, or neutrinos, that definitely do not make up those protons. The only way to explain that is by saying that the energy of the collision was sufficient to excite the field of whatever particle I’m producing. Just like how I can excite a string to different modes of vibration. The string is always there, doing nothing until I pluck it (excite it).
If gravity is a manifestation of geometry, is there a reason for why we should believe there would be a particle theory of gravity?
Well, one can show that you can derive Einstein’s Equations by looking at the theory of massless, spin-2 particles, and assuming various things (like Lorentz invariance, and reasonable properties of the S-matrix). So you don’t have to approach GR from the point of view of geometry, though that is the typical (and, perhaps, easiest) way to learn it. In fact, Weinberg’s textbook on the subject is famously non-geometric.
One new class of objects appears to have been added to the inventory of what the Universe is composed of: UNBOUND, planetary-mass “nomads”.
http://groups.google.com/group/sci.space.news/browse_thread/thread/2ee3f733a8d98312#
There appears to be somewhere between 0.4 TRILLION and 2 x 10^16 nomads roaming the Galaxy.
That’s 2 to 10^5 times the number of stars. That ain’t chopped liver, or “mystery bumps”.
Only one theory known to me predicted such a wildly unexpected result: Discrete Scale Relativity.
#11 max, the Higgs field and its particle has not been proven yet either, but it’s used. Isn’t it?
Yes, but the Higgs field doesn’t have anything to do with gravity. What’s your point?
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