What's inside a proton?(physics.stackexchange.com)
physics.stackexchange.com
What's inside a proton?
http://physics.stackexchange.com/q/81190/25561
23 comments
I've been having discussions about this with my brother about this recently (who is a million times smarter than me) and it's remarkable to me that all throughout school we think of matter at real, solid stuff we see around us while subatomic particles are virtual abstractions used to describe the solid, real stuff. I never could've understood quantum field theory in those days (and still probably don't for the most part), but from what I do understand it's turned my previous "knowledge" upside down - EVERYTHING is made up of fields or pure mathematical structures, even the empty space around us, and it's the matter and particles which we can see and feel that is a virtual abstraction made up of those fields.
I recently came to this point of view. What surprised me is how much more natural and organic fields feel to me. Much much closer to our perception of the world than some geometrical abstraction you start with. Almost wish school taught that first.
The best answer is from David Z, which is still not the top one.
The deleted answer was actually a great point, it was basically a nitpick on the first sentence of David Z's answer.
A proton is really made of quantum fields.
A proton is described as made of quantum fields.
I think it depends on which philosophical school of though you subscribe to. One could just as well argue that the concept of a "proton" is just a useful abstraction and the quantum field is not just a mathematical tool but a more fundamental model of the underlying reality - that ontologically, the field is what actually exists.
Actually I am a Kantian idealist, who experienced QFT calculations. On the other hand, I have no first hand experience of a proton. So yes, I stand corrected.
But empiricism dictates, that the experiment is correct and the theory is just a description of the experiment. And if we discard empiricism, then we can not really talk about physics anymore.
But empiricism dictates, that the experiment is correct and the theory is just a description of the experiment. And if we discard empiricism, then we can not really talk about physics anymore.
I love the idea of someone having "no first hand experience of a proton" :-)
So you also effectively acknowledge the content of the whole David's answer. The nitpicking point is just the very first sentence, not anything material in the answer, and only that he wrote "is really made of" instead of "is currently best described as made of." Nitpicking indeed, and irrelevant to anybody reading the whole answer and comparing it with the rest. Because he explicitly shows what and how we are now able to observe, compute and predict. It's the others that present the topic in absolutes.
Once we accept the basic staring point that physics is the loop in which we do the experiments, refine the models, then refine the experiments, etc, we simply don't need to insist on disclaimers that we do it that that way in every our statement.
Most of the other answers come from the previous iterations of the described loop, David's from the more recent.
Once we accept the basic staring point that physics is the loop in which we do the experiments, refine the models, then refine the experiments, etc, we simply don't need to insist on disclaimers that we do it that that way in every our statement.
Most of the other answers come from the previous iterations of the described loop, David's from the more recent.
Yes, it is a great answer. But someone did make this point, and deleted his comment. And I thought, that this is a interesting detail, which should not be lost for the discussion.
Edit:Grammar.
Edit:Grammar.
sorry for deleting the comment, liked David Z's answer but got downvoted heavily, so i didn't want to bother this thread with philosophical discussions. But now after seeing further discussions half a day later, I think I did wrong. So thanks for great discussions.
i was pointing out a problem you may read in feynman's and gerard 't hooft's writings and early quantum physicists, when it comes to interpreting quantum phenomena. What is is? do Mathematical entities have outside existence? Kant, Brentano, Frege, Heidegger, empiricists also touched this issue.
ps: I'm a physics graduate and studied/did lab work with CERN neutrino oscillation researchers, so I like such discussions wherever they pop up.
i was pointing out a problem you may read in feynman's and gerard 't hooft's writings and early quantum physicists, when it comes to interpreting quantum phenomena. What is is? do Mathematical entities have outside existence? Kant, Brentano, Frege, Heidegger, empiricists also touched this issue.
ps: I'm a physics graduate and studied/did lab work with CERN neutrino oscillation researchers, so I like such discussions wherever they pop up.
The more correct analogy is not to C but to binary executable code. But that weakens the analogy because it's much less comprehensible.
Anyway, this is a rabbit hole that one can go down however far one desires. Even time and space are just theoretical constructions. At some point you have to draw a line and talk about "reality" rather than drowning in a depthless sea of metaphysical hedges.
Anyway, this is a rabbit hole that one can go down however far one desires. Even time and space are just theoretical constructions. At some point you have to draw a line and talk about "reality" rather than drowning in a depthless sea of metaphysical hedges.
The analogy I was thinking of, is the situation where we find a alien computer, running a twisted raytracing doom. In which a Imp is hunted by hordes of humans with chainsaws. At some point we would probably have a bug compatible C version of this program. But does this mean that the original program consists of C?
But I agree, this is a rabbit hole. ( I am not as sure, that it is depthless. ) And of course, if we would need to carry all this meta physical baggage always, then we could not do anything of practical importance.
But I agree, this is a rabbit hole. ( I am not as sure, that it is depthless. ) And of course, if we would need to carry all this meta physical baggage always, then we could not do anything of practical importance.
>>So in a way, this is saying that a raytracer is made of C?
Yes, but isn't it?
>>The problem with this statement is, that a observed object is said to be made of a mathematical abstraction.
These fields are very real, it is our understanding of them that is perhaps inaccurate!
Yes, but isn't it?
>>The problem with this statement is, that a observed object is said to be made of a mathematical abstraction.
These fields are very real, it is our understanding of them that is perhaps inaccurate!
>>>So in a way, this is saying that a raytracer is made of C?
>Yes, but isn't it?
If you understand 'made of' as: a program that produces identical output from the same input can be expressed in C, then absolutely.
> These fields are very real, it is our understanding of them that is perhaps inaccurate!
Again, this depends on the precise meaning of the words. To start with a analogy, at some point the gravitational force was understood as a instantaneous action over some distance, nowadays it is understood as curvature of the space-time. So if you say that 'the fields are real,' then you implicitly claim that they are fields. And as our understanding evolves, perhaps we will call them something else entirely, we may not even describe them as fields anymore than today gravity is described as a action at a distance.
So you may argue, that this is just semantics. But semantics become important, when you have a theory which predicts that the fundamental particles of the theory can not be observed in isolation. If the only thing that you actually observe is the response of a 100-ton detector, and where you heavily post process the data you gain from observing the detector.
>Yes, but isn't it?
If you understand 'made of' as: a program that produces identical output from the same input can be expressed in C, then absolutely.
> These fields are very real, it is our understanding of them that is perhaps inaccurate!
Again, this depends on the precise meaning of the words. To start with a analogy, at some point the gravitational force was understood as a instantaneous action over some distance, nowadays it is understood as curvature of the space-time. So if you say that 'the fields are real,' then you implicitly claim that they are fields. And as our understanding evolves, perhaps we will call them something else entirely, we may not even describe them as fields anymore than today gravity is described as a action at a distance.
So you may argue, that this is just semantics. But semantics become important, when you have a theory which predicts that the fundamental particles of the theory can not be observed in isolation. If the only thing that you actually observe is the response of a 100-ton detector, and where you heavily post process the data you gain from observing the detector.
I think analogies that are supposed to make things easier to understand end up making things more confusing when you never get the straight answer. Even if I don't really know quantum mechanics, I can relate to the fact that the proton is really made of mathematical models plus whatever it looks like in a collider -- that's all we have to work with, and it defies any simple description. I can understand that.
Off topic, but I wanted to clear up a misunderstanding you seem to have. An ELF binary contains machine code. "Shell code", in the sense that I think you're using it, is specific machine code that spawns a Unix shell process, as used in exploits. (Its other meaning is code that is interpreted by a shell, but I don't think you meant that.)
Wait, shell code does not mean "here we inject machine code, that arbitrarily happens to spawn a shell" and instead means "here we launch a shell"? How did I miss that.
I didn't realize the inside of a proton was so complicated. we usually just say "2 top quarks, 1 bottom quark", etc.
And yet QCD is much more complicated than this... we never go back and reconcile it with the simplified version we saw in high school science class.
And yet QCD is much more complicated than this... we never go back and reconcile it with the simplified version we saw in high school science class.
[deleted](1)
One of my professors was fond of saying, "the proton is a garbage dump," to emphasize the mess of gluons and virtual quarks that you see when you start to probe the proton.
It's also worth noting that the in the LHC, which collides protons, most of the interesting collisions are due to gluons interacting, rather than the quarks.
It's also worth noting that the in the LHC, which collides protons, most of the interesting collisions are due to gluons interacting, rather than the quarks.
http://profmattstrassler.com/articles-and-posts/largehadronc...