Obviously the roll-eyes would indicate you don’t agree with the statement you made, however it is pretty much true that they were unified long ago.
In 1926 Schrodinger published his equation and also in 1926 year various physicists published the relativistic version of it which is now known as the Klein-Gordon equation. The Klein-Gordon equation places space and time on the equal footing that is required for special relativity and in fact Schrodinger himself had also arrived at the relativistic version in 1925 before he arrived at the actual Schrodinger equation, but opted to use the latter. One reason he probably choose to use the latter is that it’s solutions aren’t the wavefunctions of the Schrodinger picture.
However in order to arrive at a relativistic equation whose solutions were the wavefunctions of the Schrodinger picture, didn’t take much longer and in 1928 Dirac published the Dirac equation, the equivalent of the Schrodinger equation in relativistic quantum theory. As the predictions of the Dirac equation require careful interpretation it took an additional few years for it’s implications to be fully understood, however the prediction of the positron (1931), for example, was inherently a prediction of relativistic quantum mechanics rather than its non-relativistic counterpart.
It’s the marriage between quantum theory and the general theory of relativity where the actual problems start to occur.
I find it really humorous when people get all pompous and think that they’re impressing the peasants. But in spite of the fact that I’m not trained in any of these topics, I just have graduate degrees in law and finance, I still follow the literature more closely than you obviously do, especially if you could make the comment you did above about a cover article in New Scientist.
But I’ll let you go back to that warm glow of feeling superior. Hope I didn’t harsh your buzz dude.
Yeah. I’ll take YOUR word for it. As someone who’s been an avid reader of lay science publications for a few decades, New Scientist is second only to Science News. They do tend to be a bit more sensationalist, but they ARE accurate if you’re not the weak minded sort who’s swayed by that.
Eh, I’m a practising physicist, for what it’s worth. And not exactly the only one who thinks New Scientist has gotten silly.
But more generally, I think publications like that do a real disservice to lay-people who are interested in physics. There are a lot of people who are willing to spend a lot of their free time and effort learning about physics, and the community really should put forward a lot more material that makes such people able to understand concepts in a real way. Instead crap like New Scientist and Michio Kaku type babblers fill the void, and pump people full of a bunch of vague handwaving about time-and-space that not only are impossible for their audience to understand, but in a lot of cases, don’t really have anything behind them to understand.
By all accounts Leonard Susskind’s new book is pretty good and attempts to explain actual physics to the lay-person. I suggest your time would be better spent tackling stuff like that then reading New Scientist. Things like Lagrangians might seem less sexy on the surface, but there’s far more there then in the “timey wimey” handwaving that makes up a lot of physics pop-science.
You couldn’t do any better than a quote from 2006 huh? Like I said, I have a better handle on what constitutes a good lay science publication than you do obviously - regardless of your qualifications.
You might be interested to know that I do read other sources as well. I know that must be shocking, but it’s true. For example I read Physics World and Fermilab’s newsletter which is quite good. I could go on but I don’t want to tucker you out - you know, with the unsolicited advice.
I appreciate the consideration and I will try to be less snarky, however I have little doubt as to the motivations behind the post I responded to and while I will not claim I was responding strictly in kind, I think I’ve said enough that you understand the sentiment I’m trying to convey. Again, thank you.
Boys, boys, boys, this is MY thread and it’s about ME. Take your petty squabble to the “Letters to the Editor” column in Proceedings of the Royal Society, where such things have belonged for hundreds of years. Or you could write each other intemperate letters, which has gone on for millennia.
Now, these “field” things. They’re just “there,” a part of an object with a charge, just like the object’s color? It helps me to understand things by visualizing them, and I’m seeing that the field extends, theoretically, to the limits of the universe, though it gets weaker due to the Inverse Square Law (which is something I learned about after high school, maybe at the SDMB), right? So the soft caress of that field going past an antenna creates a current in the antenna? (Let’s put Quantum Mechanics aside for the moment. I’d rather understand things wrong for now than get completely confused. Not that I have a horse in the Relativity vs QM race. I’m an innocent and both seem reasonable and not mutually exclusive. String Theory, OTOH, sounds like bullshit.)
I also visualize things tactilely (I tactilize?), and the field around a bar magnet in my head is fuzzy, but that may because I played with my Wooly Willy too much as a kid.
Oh my. I guess I really should STFU. I didn’t mean for you to walk away thinking several of those things so I’m really sorry about that. The thing is, and this is pretty much what I think everybody does on some level, is they pick some level of abstraction where things make enough sense that they feel comfortable and anything that is “below” that gets "black boxed’. I’m guessing you know what that means, but if not, you just accept it as gospel and don’t think much about it - turtles the rest of the way down so to say.
As for the relativity - QM business, they are both wildly successful theories which had remarkable predictive value as we’ve seen over the decades. The issue I believe has to do with the fact that relativity makes time a “physical” dimension whereas time is handled completely differently in QM. I think this is also related to another issue having to do with spacetime being smooth an things in the quantum universe tending to be discrete or precisely what relativity says they can’t be - but I’m pretty sure I did a good job of butchering that bit. The point is that the problems come when you try to create a unified field theory that can account for all of the known forces - electro-weak, strong (nuclear and color) and gravity. Again, apologies.
Why do you keep apologizing? And, for the record, I’m not “black boxing” QFT, which must be true because of its initials. I just wanted to put aside the makeup of a field because: My original hypothesis was wrong, I decided that I had learned enough from you guys that I could continue designing my “radio” doohickey in my head ;), and that I haven’t gotten to my three Feynman audiobooks yet.
I would appreciate some discouragement from listening to books on things I don’t understand, since it took me 25 minutes the other day to read and reread a single page in a mathematical print book, only to give up and go back to my history of baseball.
Learning is such a personal thing, there’s no “good” advice. I’d even expect it to depend a lot on the subject as to what would work best. There are certainly different levels of understanding for everything and here, at some point not really grasping the math to at least some extent would probably come back to bite you in the ass. I guess the real issue though is, to what extent do you care.
edit: for example, I studied Buddhism for most of my years in college. I wasn’t enlightened when I left, but it vastly chanced my beliefs, perceptions and even how I think about things.
Have I mentioned that, for most of the past 35 years, my job titles were some variation on “engineer?” It’s amazing how long you can dummy your way through things, especially with a CAD system. Need to calculate something? Draw it and ask the computer. Not even adding columns of figures (I would do it three or more times with a calculator and go with the answer I got twice).
Given that, in recent weeks, I’ve “come out” to you people, whom I respect, about the limitations I, a professional know-it-all here and IRL, have always worked around, I think I’m starting to care a lot more than I ever expected to. Which is interesting to experience, so I appreciate your patience and help.
Particularly in light of OP’s genial and open self-deprecation–not uncommon in GQ, which is nice–I’m troubled by your response to Asymptotically fat. It seems to have shut down a thread and chased away posters.
I’ve followed your many posts because you are a layman deeply interested in physics, and you both post and elicit probing questions and answers. Hell, you’re the kind of person who posts in MPSIMS the discovery of a quark. And yes, you have graduate degrees in Law and Finance.
So surely you must be aware of who you have been talking with here for some time. The Usual Suspects. I’m not here to be a party host, but perhaps some posters in this thread haven’t picked up on others’ strengths. Not that they’re “right” in their posts, but that they respond with a distinct absence of WAGs and snark in certain areas.
I don’t understand how on Earth you could, or would want to, make the reply I quoted above to someone who, in a random cite from last month, felt it necessary to write the following, as an ETA no less:
[spoiler]…Edited to add: I see this has been pretty much covered anyway.
In its simplest quantum physics says that all the possible states that a system can be in (i.e. its quantum state) at a given time, where each state is encapsulates all the information that it is possible to know1 about the system at that time, can be represented by a state vector2 and the complete set of state vectors form a Hilbert space3.
The way I like to think of this is that each different state or ‘configuration’ of a quantum system is a pointy arrow in some abstract mathematical space.
In a Hilbert space the notion of to two vectors being “at right angles” to each other exists just as it does in the familiar real 3 dimensional vector space (indeed a 3-D real vector space is a Hilbert space), this is known as orthogonality. Of course simply saying this doesn’t tell us much about the implications of orthogonality of quantum states and what orthogonality indicates is a certain kind of independence between two states.
A quantum measurement of quantum mechanics, is represented by a self-adjoint operator4 on the Hilbert space and each self-adjoint operator has a set of characteristic real values (eigenvalues) corresponding to the different possible results of a measurement5 and each eigenvalue has an associated characteristic vector (eigenvector) corresponding to the state of the system immediately after the measurement has been made which has returned the associated eigenvalue. The eigenvectors of self-adjoint operators (when they exist) are always orthogonal to each other. In other words the different possible quantum states of a system after a measurement are orthogonal to each other.
Given a quantum system in an unknown state and you are told that the system is either in state |a> or state |b> you can make a measurement which reliably determines which state the system is in iff |a> and |b> are orthogonal.
1The notion of a quantum state can be extended somewhat to include states which do not encapsulate all the information that it is in principle possible to know about a system (mixed states), these are represented by density operators on the Hilbert space.
2Technically each quantum state corresponds to a “ray” as multiplying the state vector by a scalar can alter the state vector, but not the quantum state it corresponds to.
3A Hilbert space is just vector space where there is an inner product (i.e. a way of multiplying two vectors to produce a scalar that conforms to certain rules) and that inner product can be used to define a metric (‘distance function’) on the space which is suitably doesn’t have any holes in it (i.e. it is Cauchy-complete).
4An operator on a vector space is a function(al) that takes a vector in the space as it’s argument and maps that to a vector in the same space. Self-adjoint operators are chosen because they have real eigenvalues (when the exist) and the associated eigenvectors are orthogonal.
5 Not technically true as the set of characteristic values/eigenvalues can be empty, but this is not actually problem.
[/spoiler]
