what is a field physically?

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Anonymous Wed Jun 27 03:29:30 2018 No.9834000 [Reply] [Original]

what is a field physically?

>>	Anonymous Wed Jun 27 03:54:27 2018 No.9834020 That's like asking "what is a line physically". Question doesn't really make sense. A field is a model of a phenomenon.

>>	Anonymous Wed Jun 27 04:32:37 2018 No.9834062 >>9834020 aren't particles defined to be excitations in a field? what are the fields with regards to fundamental interactions?

Anonymous Wed Jun 27 04:39:32 2018 No.9834069

>>9834020
to extend my question, im asking what the strength of an interaction indicates beyond just laws or conditions things must abide by. are they merely just that, laws? is there no physical foundation for how the adherence to the proportions a field models is in fact a causal relation to some underlying physical structure or symmetry? if i'm comprised of particles adhering to laws that can be modeled by a field, and then we say they're all fields, what is a field? if you say it's just a model, that's like saying we're all just a model of the laws that must be adhered to, which makes no sense. how can we just be laws? what are the particles adhering to these laws? we treat them as reference points but is there nothing more to them than just pointillism and parameters that they must have in order to justify their interactions?

>>	Anonymous Wed Jun 27 04:58:50 2018 No.9834090 File: 512 KB, 480x270, autism.gif [View same] [iqdb] [saucenao] [google] >>9834020 sigh what is the physical phenomenon that the meme called 'field' is modeling

Anonymous Wed Jun 27 05:35:43 2018 No.9834111

>>9834090
space with added structure in every point. The structure is called 'curvature' in relativity AND 'particle' in quantum mechanics

Curvature on a point in space describes how the relationships to that point are changed according to the curvature tensor. For relativity it is about mass causing the tensor.

The main ideas of a particle is that of a collision, and mass. When two particles are forced to share the same point in space, an interaction will happen. Only after the interaction has occurred, movements can proceed. Mass of a particle can exist as a rest mass (giving unique intrinsic structure to it) or as momentum. Every particle seems to possess internal momentum called spin. Based on spin particle is fermion or boson. Fermions collide by reacting, bosons collide by interference.

Anonymous Wed Jun 27 05:43:11 2018 No.9834116

A field is just a defined region of space. A magnetic field is a region of space where magnetic effects can be observed, a gravitational field is a region of space in which gravitational effects can be observed, and a mine field is a region of space where explosive effects can be observed

>>	Anonymous Wed Jun 27 05:46:11 2018 No.9834121 >>9834116 So you are saying no field is infinite?

Anonymous Wed Jun 27 06:06:20 2018 No.9834136
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>>9834000
A map of the forces that would be present on its respective particle would it be present on a given location.
This definition can be broadened to incorporate stochastics, dynamics and effects other than forces.
One can also define structures (also called fluctuations) in a field that behave EXACTLY like particles, where after it becomes possible to describe fields without imagined particles. The field then describes the forces on a fluctuation of itself would it be present on a given location.

>>	Anonymous Wed Jun 27 06:32:16 2018 No.9834163 >>9834136 Maybe you should learn how to express yourself.

>>	Anonymous Wed Jun 27 06:43:15 2018 No.9834174 File: 2.93 MB, 826x647, Opus Magnum - Invisible Ink - 2017-11-02-12-39-58.gif [View same] [iqdb] [saucenao] [google] >>9834163 Go eat a dick

>>	Anonymous Wed Jun 27 06:47:45 2018 No.9834177 >>9834121 all fields are infinite. doesn't mean much though, it is just an easy way to help describe limiting behavior of whatever force you're dealing

>>	Anonymous Wed Jun 27 15:22:47 2018 No.9834908 >>9834111 Why/how does the internal momentum of a particle change the way it collides? And are all interactions between particles collisions?

Anonymous Wed Jun 27 15:31:43 2018 No.9834924
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>>9834000
Mathematically speaking, fields can be vector or scalar in nature. They are defined at every point in space and can change with time. There are gravitational fields, electro-magnetic fields, and potential fields.
Physically speaking idk we just pretend they exist irl even though space isn't really euclidean and mite b discrete it just werks lol do the calculations
t. engineer.

>>	Anonymous Wed Jun 27 16:21:09 2018 No.9835009 >>9834000 Commutative ring with no non-zero proper ideals.

Anonymous Wed Jun 27 16:52:14 2018 No.9835048

>>9834090
What kind of question is that? The electric field models the phenomenon of charged stuff attracting each other. The magnetic field models the dynamics of magnets, and so on.

Charged particles and magnets move around JUST AS IF they obeyed some law of motion (Lorentz) that refers to some vector field. That's what a model is. If you want to use this as evidence that, since the fields work so well, they must represent something that "really exists", go ahead, but that's not physics anymore.

>>	Anonymous Wed Jun 27 16:53:25 2018 No.9835051 thinly veiled ken wheeler thread

>>	Anonymous Wed Jun 27 16:57:32 2018 No.9835055 Any system where you can associate some number of degrees of freedom with every point in space Alternatively, any system that can be accurately described as a mapping of all of space onto some rank of tensor

>>	Anonymous Wed Jun 27 17:02:29 2018 No.9835061 >>9834121 The mine field totes isn't, although it might seem like it. Other fields can be considered "finite" in the sense that 0.999... can be considered 1

>>	Anonymous Wed Jun 27 17:07:23 2018 No.9835070 >>9834000 A small light show as it travels down the tunnel of entropy.

>>	Anonymous Wed Jun 27 17:09:50 2018 No.9835076 >>9835048 the absolute state of "science"

>>	Anonymous Wed Jun 27 17:13:22 2018 No.9835080 >>9835076 Yeah, science is about making claims that are not baseless.

Anonymous Wed Jun 27 17:16:59 2018 No.9835089

>>9835076
The fuck is wrong with developing models that fit observed phenomena without [[[[DEEP]]]] knowledge of what's [[[[REALLY THERE]]]]? It's a basic investigative technique to fit the relation between two things using statistical methods, why shouldn't it be fine to keep at it when it workscomes?

Anonymous Wed Jun 27 19:03:04 2018 No.9835259

>>9835048
This makes me feel sad - all the knowledge we have is "models". We can never really know the ultimate truth of anything, we can only build models that simulate it.

Reminds me of Walt Whitman:
"A child said What is the grass? fetching it to me with full hands;
How could I answer the child? I do not know what it is any more than he."

Anonymous Wed Jun 27 19:12:29 2018 No.9835277

>>9835089
>developing models that fit observed phenomena
Because you're pretending these models are natural science, they are not, they are not science, they are metaphysics. Yes, that includes the heliocentric model.

Real science doesn't use models, it uses reality.

>>	Anonymous Wed Jun 27 19:12:31 2018 No.9835278 >>9835259 >Walt Whitman confirmed brainlet

>>	Anonymous Wed Jun 27 19:13:34 2018 No.9835284 >>9835277 What are some examples of "real science"?

>>	Anonymous Wed Jun 27 19:20:55 2018 No.9835303 >>9835284 Observing, testing, measuring and repeating the behaviour of physical objects.

>>	Anonymous Wed Jun 27 20:02:53 2018 No.9835391 >>9835303 models of physical objects obviously.

Anonymous Wed Jun 27 21:01:40 2018 No.9835480

>>9835259
>all the knowledge we have is "models"
Models that make accurate predictions about observable phenomenon that we can test and measure.
The standard model predicted particles that must exist for the model to work, and one by one they were discovered. It works way to well to just be "people making shit up" or dumb luck.
Moreover, you personally do not observe and interact with an objective reality. Perception is, by definition, a self consistent hallucination of sensory feedback your brain feeds you to help navigate the world around you and not die horribly. It is a model. Literally the ONLY thing you can know about the world is a model. solipsism 101.

Anonymous Thu Jun 28 05:19:40 2018 No.9836016

>>9834020
if all particles are excitations of fields(waves), all the particle interactions are wave interactions, and we see on a macroscopic level that waves always propagate in a medium, then what is that medium on the quantum level?

if there is no medium, then what gets excited(transmits waves) to result in what we observe and call particles?

>>	Anonymous Thu Jun 28 05:38:04 2018 No.9836034 What IS it? No one knows. All we can do is quantize it.

Anonymous Thu Jun 28 05:45:49 2018 No.9836043

>>9836016
As I said, no one knows. Watch David Tong's talk at the Royal Institution.

But really, asking "what is a field, really?" is the same as asking "what is the universe, really?" Why does it exist. As Feynman said in that famous interview, the chain of 'why' question is almost certainly literally infinite. We must accept that we must stop our line of questioning at some point and live with simply not knowing, until technology advaces and we can go a step further. But the bigger point is that this path is potentially endless, and we will never know all the answers, because this is impossible.

Anonymous Thu Jun 28 05:58:11 2018 No.9836046

>>9836043
Thank you for the clear answer.

Having that "unknown" in mind, on a previous thread, there was a discussion of light having no medium being proven by the Michelson–Morley experiment. If this is correct, how did the experiment prove that light has no medium? Are there other examples similar to light?

>>	Anonymous Thu Jun 28 06:02:48 2018 No.9836049 >>9834000 phsics deals with objects a field is a concept answered/thread

>>	Anonymous Thu Jun 28 06:04:49 2018 No.9836052 >>9835278 Please stop with your arrogance and willful ignorance and read this entry on scientific realism vs antirealism https://www.iep.utm.edu/sci-real/

Anonymous Thu Jun 28 06:13:15 2018 No.9836061

>>9836046
Basically, the michelson-morrey experiments wanted to see how fast the earth was moving through the light medium, since Maxwell's electromagnetism predicted a constant speed of light. The TLDR of it is if the earth is orbiting the sun, that means its velocity changes with the seasons. If the speed of light is constant in a stationary medium, that means its travel time should vary slightly based on which direction the earth is moving.

They consistently found no change in the speed of light at any time of year, leading people to speculate that there was no stationary medium, and the speed of light is constant in all reference frames. So far we've found no evidence to suggest the inclusion of a physical medium is necessary for a consistent theory, so it's been dropped

>>	Anonymous Thu Jun 28 06:50:25 2018 No.9836091 >>9835009 This man gets it

>>	Anonymous Thu Jun 28 06:55:38 2018 No.9836097 >>9835009 beat me to it gdi

Anonymous Thu Jun 28 07:03:40 2018 No.9836109

>>9836061
If I understand you correctly, the Michelson-Morley expected results were for light to be faster at sunrise and slower at sunset, or something to that effect. But it`s speed turned out to be constant.

Why would constant speed mean lack of a medium, when you measure from the reference frame of the Earth, not from that of such a medium(if it exists)?

Doesn`t light propagate through the same above-mentioned "unknown"?

How would that "unknown" constitute anything different than an "aether"(i mean in non-trivial terms)?

>>	Anonymous Thu Jun 28 07:09:42 2018 No.9836113 >>9834000 Nothing

Anonymous Thu Jun 28 07:52:17 2018 No.9836159

>>9836109
Let's imagine we're in a universe where ocean waves always move at 7 mph in the water.
You're in a boat, trying to figure out how fast the boat is going. Clearly, if you're moving at 3 mph, you'd expect ocean waves going in your direction to move at 4 mph away from you, while waves approaching you move at 10

But if repeated experiments keep showing a 7 regardless of how fast the boat is going, you have to start asking what the fuck is up with this ocean, and that's where the parallel breaks down because this weird ocean is presumably made of water, while we can't directly observe what space is made of, if it's even made of anything.

Anonymous Thu Jun 28 07:55:06 2018 No.9836162

>>9834090
nobody knows and nobody can know, just like with anything else. What does "knowing" something even mean, really?

but it we pretend things like fields and electrons and shit really exist the numbers all add up so who gives a shit at the end of the day. Until someone comes up with a better fantasy model that predicts experimental results better.

>>	Anonymous Thu Jun 28 08:30:03 2018 No.9836201 >>9836159 It's a cosmic, simulated zoo. I won't call it god, but someone is watching

Anonymous Thu Jun 28 08:36:36 2018 No.9836210

>>9836159
So then what this means essentially, is that light propagates through space, which we can`t measure/observe. But then what is wrong in saying that the medium of light is space? Should the inobservability of the medium in which light travels, preclude the possibility of its existence?

Don`t the measurements of gravitational waves change that inobservability?

Again referring to the above-mentioned "unknown" that when excited is observed by us as particles, wouldn't it be a prime candidate for that very same medium through which light propagates?

Anonymous Thu Jun 28 08:38:46 2018 No.9836213

>>9836052
Einstein was a realist while Bohr was an instrumentalist, which I think is a good alternative to both. There may never be a theory of everything (outside of string theory) because of something in string theory they call landscapes, which basically just means that the laws of physics we know only apply locally. We just learned for example that the laws of physics in a black hole's singularity break down, same as in the singularity of the big bang. This place is a lot stranger than realists like Einstein are willing to accept.

>>	Anonymous Thu Jun 28 08:39:14 2018 No.9836215 >>9834924 >engineer doesn't know about spinor fields

Anonymous Thu Jun 28 08:53:57 2018 No.9836231

>>9836210
I mean you can call it a "medium" if you really want as this is now the territory of philosophy you're crossing over into, even though this "medium" shares very few peoperties in common with things that are technically referred to as a medium, like air or water. The aether was supposed to be literally like that. So that's why it's not really thought of as a medium. You can invent your own term and call it "a very special sort of medium.. that's not really like a medium.. about which we know almost nothing."

Well, at least we finally know one cool thing about it that was a mystery for a long time, and it's that it is continuous and not discreet. Obviously air and water are not, so that's one important difference.

Anonymous Thu Jun 28 09:23:59 2018 No.9836274

>>9836159
Also, if space can vibrate, and the boat, the sea and all particles are composed of vibrations, then what makes you think your example should not be applicable to light?

If you can see waves moving around your boat. And you your boat speed instruments tell you your boat is moving at 7mph. Then you decide to measure the speed of the incoming waves vs the waves going away from the boat behind it. Both readings would say the speed of the incoming and outgoing waves is 7mph. Then the sea(light) would be a standing wave. This can explain how the incoming and outgoing waves` speed could be equal, but of course cannot explain why the speed of the waves would not change with that of the boat.

Also, doesn't Romer's determination of the speed of light prove an opposite result to that of Michelson-Morley? (the periods of Jupiter's Io are shorter when the Earth is approaching Jupiter than when receding from it)

>>	Anonymous Thu Jun 28 09:28:44 2018 No.9836281 >>9836162 This. The way we talk about this can only ever be in analogies

Anonymous Thu Jun 28 09:54:36 2018 No.9836315

>>9836231
I am not into petty terminology arguments so don't want to call it a medium or not, I want to understand how "it" differs from a medium.

I also do not care for aethers, I mention them(if i even did so) inasmuch as I want to understand how the current approach differs so "vastly" from such notions, as to spark so much controversy and denial.

If one says that the Michelson-Morley experiment proves that light has no medium, then it turns out it does, but it is hard to observe, then it can be said that it does have a medium. If this medium is space and space is "nothing like any known medium", but then it turns out that vibrations can propagate through it to be detected by us as what we call particles, and we even detect gravitational waves, then it would seem even more of a medium. That is not to say an identical medium, but a medium nonetheless.

Thus if the above is true, in lieu of the annus mirabilis revolution in physics, which supposedly turned physics on its head, we see a normal Lorentz-Poincare-Einstein progression of ideas, the "miraculous" notion of which only stemming from our ignorance as to the nature of space-time, not due to some "magnificence" or uniqueness of the "discovery" itself. A similar statement would be saying that 1514 was an annus mirabilis, whereas the Heliocentric model had been formulated by Hipparchus, thus rendering the event a testament to our idiocy in forgetfulness, ignorance, and <misunderstanding> of past models, be they millennia(Hipparchus) or decades(Lorentz-Poincare) distant from us.

Wouldn't a model which balances familiarity (with existing models)with novelty be best conducive to scientific research, instead of saying "we don't know, but it is <nothing> like aether, nothing like medium", or is that mindset more akin to that of the quick realization that it is easier/safer to define something unknown as what it isn't, rather than to venture into the questions of what it is.

Anonymous Thu Jun 28 10:06:31 2018 No.9836331

>>9836281
People get so hung up on what is "real" or not when at the end of the day your view of the world comes through a couple narrow sensory channels prone to errors, and literally every abstract concept is grounded in an intuitive feeling, an unstructured pattern that you have noticed by piecing this fuzzy data together. Every attempt to define words and semantic constructs using words and semantic constructs is just futile, since they are ultimately all proxies for subjectively experienced patterns.

Where does your notion of real come from? Where do the notions you are using to reason about it do? Why do you insist on circularly reasoning yourself up your own ass rather than just embracing the fact that logic is just a tool you can use but not some sort of magic self contained answer to everything.

Anonymous Thu Jun 28 10:09:58 2018 No.9836335

>>9836315
It's just semantics, really. A parametric field through which waves propagate absolutely is a medium, but it does not exhibit all the sorts of characteristics that people would intuitively try to tack on to a medium that consists of matter. Probably an anal attempt to avoid confusion or incorrect extrapolation.

>>	Anonymous Thu Jun 28 10:15:03 2018 No.9836340 >>9836331 Great post.

Anonymous Thu Jun 28 10:21:48 2018 No.9836344

>>9836043
>"what is the universe, really?" Why does it exist. As Feynman said in that famous interview, the chain of 'why' question is almost certainly literally infinite. We must accept that we must stop our line of questioning at some point and live with simply not knowing, until technology advaces and we can go a step further. But the bigger point is that this path is potentially endless, and we will never know all the answers, because this is impossible.

That`s like saying, what`s the point in screwing a woman, when I can`t screw them all, fuck it, let`s give up. Of course Feynman cannot explain all of the why`s, but he is wasting his time explaining that he cannot explain all the why`s, instead of explaining the why`s that he can. That is the difference.

The why is crucial, as is the how and the what. It is a causal chain, of which you have to explore, prove and share as much as you can. Of course you have to ask why, of course you have to come up with wrong theories, invent enough of them and you get to the "correct" one.

>>	Anonymous Thu Jun 28 10:27:46 2018 No.9836350 >>9836344 He didn't say "you should lie down and die." He was definitely not against knowing as much as is possible. But yeah, he was famously anti-philosophy

>>	Anonymous Thu Jun 28 10:30:21 2018 No.9836352 >>9836344 What he says is you can maybe go deeper and deeper but you aren't ever going to "solve science". There isn't really way you can know that there is nothing more to know, only that your model is pretty darn good.

Anonymous Thu Jun 28 10:33:29 2018 No.9836357

>>9836331
Logic, and the tools that lie beyond its constraints, both can help us advance our notion of the "real". Who was the first western thinker to formulate logic as we know it today? Why was he, accidentally(?), the first to distinguish pre-Socratics from those who came later? Is logic the only way? Does logic preclude the use of other methods? Why shouldn't logic work well <together> with other methods?

"Where does your notion of real come from?" Even if all of this is a dream, what does it matter, it is all you and I have, so all we can do is study it and make the best of it. Suicide yourself, or prove it is a dream, neither matters, for science in all its various forms, including philosophy, represents our best explanation of reality/dream, art - our best representation of it, technology - our best use of it.

>>	Anonymous Thu Jun 28 10:33:56 2018 No.9836360 >>9835259 'Knowing' and 'truth' innately removes the possibility of any real substance or essence, any 'true reality'.

Anonymous Thu Jun 28 10:40:03 2018 No.9836363

>>9836352
Being unsolvable is the sweetest thing about it, an endless spring.

None of the great scientists ever did their effort for the ends, nothing but the addiction of asking <why> can explain their focus and tenacity. The climb is so much more enjoyable, it it is the essence of the journey to the "peak".

Anonymous Thu Jun 28 10:43:49 2018 No.9836367

>>9836315
Mind you I do not wish in the least to detract from the greatness of any of these men, of the results of their work, but I do wish to stress the equally detrimental effects of totally dismissing someone(and his or her work), and of blindly lauding them.

>>	Anonymous Thu Jun 28 10:44:56 2018 No.9836368 >>9836363 If you COULD "solve science", and then you did, what would you do after that? An hero for me. Thank god you can't.

>>	Anonymous Thu Jun 28 10:49:58 2018 No.9836374 a space where every coordinate is defined by either a scalar or vector

>>	Anonymous Thu Jun 28 11:04:36 2018 No.9836392 >>9835009 The zero ring is a field?

Anonymous Thu Jun 28 11:22:11 2018 No.9836406

>>9836061
Doesn't Romer's determination of the speed of light invalidate Michelson-Morley? If not, how so?

If light is just another excitation of space-time(medium, field whatever), isn't it a property of the space-time which interacts with its medium(for lack of a better word) in such a way that the medium limits it to the speed of c?
If all other vibrations we call particles propagate through the same medium, what makes us think that the fact that their speed limits are lower means that c is the upper speed limit, when there could be many other hitherto undetected vibrations propagating at higher speeds?

Could the speed of light invariance be partially due to light becoming a standing wave within the spacetime medium, whereas all other vibrations we measure remain travelling waves? This occurring due to the travelling light wave reflecting at some spacetime boundary at each instance of its propagation, so that it first propagates as standing, then during the next quantum of propagation, the last one reflects off some spacetime boundary, rendering the wave standing?

Am I right in saying that we abandon Galilean relativity to explain the invariance of light speed by saying it has a constant speed relative to a hitherto unknown medium - spacetime? How would that affect/explain the speed of light relative to anything else? Why would that automatically mean that light has a constant speed for all non-accelerating reference frames, or is it that we just no longer compare light to anything else <but> its medium?

Anonymous Thu Jun 28 11:34:30 2018 No.9836416

>>9836406
Romer's speed of light experiment shows changes in the observed time Io takes to orbit Jupiter, yes. This is what we'd expect no matter what kind of constant the speed of light is, because it deals with a change in the distance light has to travel over time. When Jupiter is coming closer, that means every second that passes, new light emitted at Jupiter has to travel a slightly shorter distance to reach us. We observe this as the orbit being slightly sped up. Conversely, when it's going away, the light has to travel a little bit further every time. This looks like the orbit slowing down. This result would actually apply regardless of whether the speed of light was constant relative to some absolute rest frame, or what it looks like, that it's invariant regardless of reference frame.

Anonymous Thu Jun 28 12:42:28 2018 No.9836506

>>9836416
Thank you for the clarification.

Based on the above posts, is it right to say we abandon Galilean relativity to explain the invariance of light speed by saying it has a constant speed relative to a hitherto unknown medium - spacetime? How would that affect/explain the speed of light relative to anything else? Why would that automatically mean that light has a constant speed for all non-accelerating reference frames, or is it that we just no longer compare light to anything else <but> its medium?

If I travel at the speed of light, would light pass me by at c?

Anonymous Thu Jun 28 12:49:08 2018 No.9836518

>>9836357
I'm not interested in metaphysics, my point is that however you define some semantic construct ultimately you will always end up appealing to shared sensory experience. There is no way to internally define a system of axioms. So the concern over whether it is "real" or not is ultimately just about how well it predicts what you end up actually observing, if the goal of your system is to describe the outside world.

>>	Anonymous Thu Jun 28 12:51:36 2018 No.9836525 >>9836374 what is a space? >a set with... Ok, what's a set? >a collection of things what's a thing? At the end of the day it's all stuff people made up to help explain shit and process input information.

>>	Anonymous Thu Jun 28 13:08:48 2018 No.9836543 >>9836392 Field with one element bruh, duh

>>	Anonymous Thu Jun 28 13:13:08 2018 No.9836549 >>9836506 From your point of view, the entire history of the universe, uncluding the death of all black holes a googol years in the future, would pass by instantly and you would never perceive anything due to infinite time dilation.

Anonymous Thu Jun 28 13:25:36 2018 No.9836567

A field is a way to conceptualize the idea of an interaction in terns of an underlying physical process that ocurrs instead of just two bodies interacting. That is, you could look at electric force as an interaction between charges, or in terms of fields as a charge generates a field and then that field interacts with thr other charge.

>>	Anonymous Thu Jun 28 13:26:54 2018 No.9836570 >>9834000 physicality is a product of field interactions so this question is fundamentally misguided

>>	Anonymous Thu Jun 28 13:27:57 2018 No.9836572 I think the question here is what does a field look like?

Anonymous Thu Jun 28 13:31:54 2018 No.9836578

>>9835277
>>9836518
Fuck off with your "metaphysics" and flat Earth bullshit. Just because you can't physically touch it doesn't mean it isn't physics or science. If you disagree with that and think all models are useless because theory isn't perfectly represented in experiment, then you do not belong on this board, much less in the scientific community.

Anonymous Thu Jun 28 13:50:53 2018 No.9836635

>>9835277
>>9836518
If you think the only things that aren't metaphysics are the things you can directly and consciously touch and see, then your universe is nothing more than protons, electrons, and photons. You can speak of nothing more. Of course you'll say those are just models and your keyboard is a physical thing, but to the scientific community those are the only three you have with no way for them to interact. Of course, then you'll try to come up with some way that two things can interact, but will appeal to a model to describe how they do, which, of course, is not physical and should not be used, because it is not scientific.

>>	Anonymous Thu Jun 28 13:54:24 2018 No.9836642 File: 7 KB, 275x183, water.jpg [View same] [iqdb] [saucenao] [google] >>9834000 imagine a body of water, you swimming in it, your field is the disturbance on the water cause by your act of swimming

Anonymous Thu Jun 28 14:00:21 2018 No.9836653

>>9836506
Einstein had two postulates for relativity:
1. The laws of physics are the same in all inertial frames of reference.
2. The speed of light in vacuum is constant (which comes from Maxwell's equations that the speed of light is determined by two constants).

Using these two postulates comes the rest of special relativity. Two consequences I will highlight:
1. The speed of light is the maximum speed (consequence of the postulates, not an assumption)
2. Time/space dilation to maintain the measured speed of light to be constant in all reference frames

>>	Anonymous Thu Jun 28 14:04:58 2018 No.9836658 File: 57 KB, 900x452, apada.jpg [View same] [iqdb] [saucenao] [google] >>9834000 wherever your body moves in the water, you will generate a field around you

>>	Anonymous Thu Jun 28 14:32:10 2018 No.9836687 >>9836572 Like if you could see a field what color would it be?

>>	Anonymous Thu Jun 28 14:38:07 2018 No.9836690 >>9836687 Depends on the frequency of the vibrations in the electro-magnetic field

>>	Anonymous Thu Jun 28 15:23:53 2018 No.9836744 >>9836635 >Of course you'll say those are just models and your keyboard is a physical thing Strawman. Any "physical thing" is an abstraction created by the brain as far as I can tell.

Anonymous Thu Jun 28 15:28:39 2018 No.9836748

>>9836744
Then how is natural science different from metaphysics if you rely on abstractions for everything? How is an abstraction different from a model?

Also, due to your lack of a comment on your science limited to protons, electrons, and photons with no interactions, does that imply you agree with that statement?

Anonymous Thu Jun 28 15:42:15 2018 No.9836765

>>9836549
So if all particles are vibrations in spacetime, and fields are but regions of vibrationally excited spacetime, then how will the high speed of propagation of my vibration through spacetime, render the whole field of spacetime around me(the rest of the universe) to evolve instantly?

>>	Anonymous Thu Jun 28 15:56:38 2018 No.9836793 It's like a field of wheat.

>>	Anonymous Thu Jun 28 16:03:51 2018 No.9836804 >>9836793 The amber waves of grain?

Anonymous Thu Jun 28 16:15:22 2018 No.9836814

>>9835277
you need to change your definition of "model" not your definition of "science". A model, like anything else we can discuss, is something that exists in reality. Models aren't astrology, they give real, verifiable results and have consequences. One of those consequences is you ignorantly shitposting here on /sci/.

Anonymous Thu Jun 28 16:15:26 2018 No.9836815

>>9836653
>1. The speed of light is the maximum speed (consequence of the postulates, not an assumption)
By postulates, do you mean that the speed of light as a limit is arrived at purely mathematically, and then later on proven experimentally? Does this mean that we do not know the logical causes behind the speed of light being the limit? That we know the mathematical logic behind it being considered a limit, but not the logical causal links that render it to be so?

>2. Time/space dilation to maintain the measured speed of light to be constant in all reference frames
Again dilation is arrived at mathematically and then proven experimentally. Does this mean that we expect and prove that
speeds cause dilation but we do not know what causes this dilation, or rather how the speed causes the dilation?

If in both cases we calculate a prediction and then prove it, then isn't this like a black box, like opening the machine code of self-learning AI? Aren't we then like magicians, we make a prediction and see if it works, and when it works we still cannot explain its underlying principles and causations?

One might argue that such an endeavour would be useless, but to discover and prove a principle is useless because it doesn't allow you to practically use the principle to its fullest extent(gps compared to a steam engine). I can mathematically construct for you a steam engine and prove to you the principles i discovered are sound, say using a geyser, but i can only build a steam engine and start an industrial revolution with it by understanding the underlying principles of its operation. I cannot build anything based on mathematical theory + proof, until I know how the causal links by which the principle works, the same links that will allow me to use the principle practically. I remember a scientist saying that science only tells us how something works and not why, which is ok. But if the above examples are true, then science no longer even tells us how things work.

Anonymous Thu Jun 28 16:35:13 2018 No.9836853

>>9836815
You might also argue that the currently explored principles of science require such high energies to utilize/manipulate that it is impossible at the current technological level or ever to learn how these principles actually operate. Yet, this line of thinking is void, since it is always a matter of scale.

If I told Henry Cavendish we would be using electricity to power cities using dams, he would hardly be able to understand how. But between the first electrical discoveries and the AC motor lie 200 years of not just math and observational proofs, but constant experiments which aim to bridge the gap and utilize the same ingenuity that crossed the distances in maths and observational proofs, to cross the bridge of causal links that leads to the phenomenon already proven, to <how> it practically happens.

In other words being right doesn't matter, so long as you cannot say how and why you are right. Does anyone even realize this? Being right doesn't matter. Is it acceptable to give Nobel prizes to people who are right?

Anonymous Thu Jun 28 16:35:58 2018 No.9836856

>>9836815
Yes, the speed of light being the limit comes out naturally. The cause is assuming the speed of light is a constant in vacuum. The speed of light in vacuum is constant for all observers in all frames. It is because of this consistency that it is the maximum speed limit. Perhaps you can convince yourself of that by going through the thought experiment used to derive time dilation with the spaceship (http://www.emc2-explained.info/The-Light-Clock/#.WzVEj3D9gy4).). Basically, time slows down for the observer on the spaceship in order to keep the speed of light constant. I'm sure there is a good way to conceptually conclude that c is the fastest, but I can't think of it right now beyond the basic mathematics.

> Aren't we then like magicians, we make a prediction and see if it works, and when it works we still cannot explain its underlying principles and causations?

That is how science works. We make models to explain how the world works and if we cannot verify (wouldn't ever use the word prove with experiments) then we toss out the model. Our knowledge of physics is an accumulation of the models that were not tossed out yet. Furthermore, there are some models that are known to be wrong that we keep around because they are useful in certain situations, but I digress. When it comes to theoretical physics, a question I often ask myself is "Does this actually make conceptual sense or have I just heard it enough times that I accepted it?" It is difficult to say what makes intuitive or conceptual sense, because you currently think that speeds are independent of the coordinate system you use and SR says transformations to frames with other speeds will change the coordinate system. Which is more conceptual of an understanding? Clearly we do not have personal understanding of traveling near the speed of light, but if we did, then SR concepts would be much more intuitive.

Anonymous Thu Jun 28 16:41:16 2018 No.9836870

>>9836815
>>9836856
Hit character limit...

Basically my point is that when you look for a deeper cause or understanding of why something is how it is (as I often have done and still do), you find yourself outside of physics and into philosophy with many ideas and no way to test or distinguish them.

I'm not sure exactly where your struggle is though, it seems like you are searching for a conceptual understanding, then saying that theory is useless unless you know what causes it (engineers would disagree as they use concepts and not where they come from). You can trace the speed limit to the frame independent speed of light, which comes from Maxwell's equations, which come from fundamental physics and experiments with magnets and coils, but I don't think saying light speed is the speed limit because I can generate a current by inserting a magnet into a coil is the answer you are looking for. So can you give an example of another bit of information you know and the causal link by which the principle works? Maybe asking in other words would help to clarify my confusion?

Anonymous Thu Jun 28 16:41:37 2018 No.9836871

>>9836572
>>9836687
Fields themselves are not measurable.
We only keep fields around because they are convenient.

The analog to this in qm is wave function. Theres no physicality to them. It's the sources of the field which are measurable and considered to be the actors.

>>	Anonymous Thu Jun 28 16:41:53 2018 No.9836873 >>9834000 The minimum space required to hold your mother.

Anonymous Thu Jun 28 16:46:16 2018 No.9836880

>>9836853
If the above is correct
a) why don`t we focus almost all of our research and funding experiments that can allow us to bridge the above-mentioned gap. The idea being to have a majority of scientists performing experiments, instead of theorizing to such extent that almost nothing practical can catch up with their theories. When the objection is given that "the energy levels(environmental conditions) required are too high we can`t do it" the natural answer would be for the experimenters to focus all their efforts on means(energy generation etc) to reach the conditions required, so that experimenting can become ever easier.
b) shouldn't all scientists preface their textbooks, articles and Nobel prize speeches with this HUGE CAVEAT
<We don't know how this works and why it works, but we found that it works mathematically and proved it to 99.9% accuracy!>? First off this seems far more honest; secondly it reduces the chance of misunderstanding since it immediately shows the limits reached in the research; thirdly it prevents the public from making false claims or misinterpreting scientific conclusions. Think of how many cooks and conspiracy theories would have been prevented if scientists just clearly mentioned the above.

Some of the anons mentioned reality. There is a big difference between reality and dreams. In reality you have causality, and although you can mimic that in a dream, in reality we have "consequences". What is the difference between the consequences of a mathematical theory, of someone being proven right, and the consequences of using those two to manipulate gravity, or build an AC motor? Time dilation is a phenomenon that is the consequence of something. We cannot use that phenomenon in any way until we can find out all the things whose consequences lead to the phenomenon. Like the AC motor is build piece by piece in many garages, so a gravity engine might be built too, but it will surely not start with someone holding a prize for being right.

>>	Anonymous Thu Jun 28 16:47:03 2018 No.9836882 >>9836052 Take it easy fella, I posted the Whitman excerpt, then samefagged to make the "whitman is a brainlet" joke. I am partially familiar with the realism/anti-realism split but that looks like an interesting read

Anonymous Thu Jun 28 16:49:38 2018 No.9836887

>>9836853
We value knowledge not for being right, but for expanding the known amount of information. Just because something isn't useful to the common man doesn't mean it is not useful. Take particle physics for example. At CERN in Switzerland, they build a particle accelerator to make new particles and observe their interactions for purely physics sake. As time went on, more physicists became interested in particle accelerators for various reasons, but many wanted to be part of the collaboration with CERN and use their data since they could not afford their own machine. Since this was before commonly known ways of sending digital information, and as it would be too costly to write it all to floppy disks and ship them everywhere, the solution to the problem was to create the world wide web to share information. Through this, the internet came about.

There are many offshoots from science that are not anticipated, and many that are never come about. The more important thing is striving for new ideas, since with new ideas, new possibilities are available. Einstein got a Nobel prize not for his work with relativity, but for the photoelectric effect. This knowledge, along with advancements in materials science and a necessity for better and cleaner energy, led to photo voltaic cells (solar).

Reasons such as these are why we value knowledge and the truly unique ideas that are independent of the ones already known.

Anonymous Thu Jun 28 16:54:41 2018 No.9836893

>>9836880
It seems you are confusing science and engineering. Engineering isn't concerned with pure science, but with practicality and how to use the ideas to make a useful product to make life more efficient and solve problems with more ease. Science is trying to discover unique models and expand our raw knowledge so that others with different interest (such as engineers) can take the ideas and do what they do. It is similar between math and physics. There is so much useless math and I don't know why someone thought of doing, but they did. As time goes on, I learn the usefulness of fractional (not partial, but non-integer) derivatives and integrals, Grassmann variables (object that is not 0, but whose square is 0). The more you look, the more you find uses. If it wasn't for mathematicians doing the "useless" math that they do, physicists would run into problems where it would be useful and have to do it on their own. At this point, I never say any math is useless, just as I would never say any concept in physics cannot be applied to make devices for the layman, but that is not the goal of science.

Anonymous Thu Jun 28 17:01:56 2018 No.9836905

>>9836880
As for part b)
> First
This is understood if you are in the scientific community

> secondly
If you are relying on prizes and honors to interpret science (and articles from non-peer reviewed sources) then you are going to misinterpret science anyway. Go directly to the source. If you cannot handle reading the material directly, you should not be working with the material to do something more or applying it. I'm not saying you're not good enough to do anything, but you should take the time to get up to speed to interpret it form the source instead of relying on others.

> thirdly
Same as before, the public gets their information from facebook, online journals, news, etc. All secondary sources. As I have been in the news in high school for a simple community matter, I know how easily they gets facts wrong and cannot report a simple story, much less something about a topic they are not experts. This is true of every field that tries to say something. Always be careful and we should put stronger constraints on reporters to check facts and specialize in a topic or field before reporting.

Typically you can see through cooks and conspiracy theories easily, as well as falsified or misrepresented data, and poor scientific practices when you are familiar with some basic things to be aware of. Being in the field and doing some research yourself helps build bullshit smelling skills.

Anonymous Thu Jun 28 17:21:32 2018 No.9836942

>>9836880
Any scientist should be able to understand, that it would be natural for the public to be incredulous and hostile to any science which expects and needs to be heavily funded for only making predictions and then proving them to be true. Any scientist should be able to understand what a non-scientist means when he speaks of "reality". Because you can compare the reality of Maxwell - observations - AC motor. What makes Maxwell`s principles more "real", if there had been invented an AC motor, or if there had never been invented one? Of course anyone would be more willing to assume his principles are real when he holds the motor in his hand, because the consequence is not just your prediction turning out to be right(you have knowledge of the principle) but that you have mastery over it, you can play with it and it still holds true. You have the why and the how which allows you to work with the science you have discovered, because you didn't just do it to be proven right, you discovered the necessary steps to push scientists beyond knowledge of the matter(forces) at hand, but <mastery> over them. Knowledge that is not applied is futile, right?

In short, we gain knowledge about a phenomenon, but not the workings of it. The first natural philosophers in Greece were called "physiologoi" from phusis(to grow, to become), from whence comes physics. Thus why don`t physicists ask "what does a field grow out of", "how does it become what we measure it to be". If we are all vibration in one and the same field what should we be able to do physically, if we obtain some control of it?

Newton discovered calculus not as some chair of theoretical physics, but because he <needed> it to explain his observations, and it is since then <practically> applied in almost all fields of science.

Some people say no government would fund us blah-blah. But we have a new Republic of Letters, we can fund and organize ourselves. Our children would have only us to blame for not researching.

Anonymous Thu Jun 28 17:28:17 2018 No.9836966

>>9836893
I do not mean to say one science is useless or another. I mean to say that:
a) knowledge not applied is useless, i.e. the less certain knowledge is applied the less useful it is
b) wasn't great science constantly supplied with great engineering, the two complementing each other? weren`t many of the great scientists also engineers?(not necessarily building with their hands, but providing the necessary theoretical <steps> to building, allowing the building of the tools both testing and utilizing the newly discovered principles)

>>	Anonymous Thu Jun 28 17:30:17 2018 No.9836978 >>9836887 Thank you for taking the time to respond.

Anonymous Thu Jun 28 17:36:23 2018 No.9836987

>>9836942
A first model is simple model what is seen. From there, speculation will be done to see if there are new predictions that arise directly from the model. As the model becomes ever more robust, more insight is gained into the connections with other phenomena. A model isn't simply a statement of an equation. Take General Relativity for example. Einstein didn't just write down a few equations and try to find an experiment to show the equation was true. There are numerous metrics that have more accuracy in situations. Research is constantly going on to solving the equations and including more features. The expertise you are looking for is saying that now that we know gravity, we should be able to make gravitons and a device which alters the gravitational field in a local region and not outside of that. Once we have our "gravity intensifier" built, then we can talk to someone about our model and how it is useful. That takes decades of work, and if work is not funded and published, there will be no collaboration. Nobody thought of quantum mechanics before finding strange events in the lab and if it were not for pure science searching for models and vast efforts into developing quantum theory simply for knowledge sake, we would not have most of our modern world.

Anonymous Thu Jun 28 17:36:40 2018 No.9836988

>>9836856
Thank you for the link.

One example,
"Basically, time slows down for the observer on the spaceship in order to keep the speed of light constant."
I understand how mathematics can come up with an explanation for time dilation, but could I ask you <what> causes time dilation when I reach the given speed?

Anonymous Thu Jun 28 17:43:59 2018 No.9836995

>>9836942
> "what does a field grow out of"
> "how does it become what we measure it to be"
> what should we be able to do physically, if we obtain some control of it?

Scientists do this. We know what causes fields, we know how they permeate space, we know how they propagate, we know how they interact. Much research has gone into these questions. Because of that, through QFT and particle physics, we have seen evidence of particles too small to see with the naked eye and are only measurable because the particles that created them were traveling near the speed of light. The new particles don't live as long as a micro second, some much shorter. Because of our expanding knowledge, we are able to predict new particles and develop new theories. We have a handle of the strong nuclear interactions, but I don't see any engineer trying to develop a battery that works off the strong nuclear interactions instead of the electro-magnetic ones; go ask them why (most likely because a company will not fund them and will take to long to develop independently and see any rewards financially).

Long story short, if you cannot see the purpose of doing pure science for knowledge sake and only want some financial gain or cool new toy, go talk to the engineers. If you think we shouldn't be doing research in science, go figure out what things you lose by not having quantum mechanics.

Anonymous Thu Jun 28 17:45:58 2018 No.9836998

>>9836871
If you can measure waves, why wouldn't you be able to measure fields?

Let us say, in short, that the Maxwell equations describe <how currents of particles produce fields> and the Lorentz force describes <how fields act upon particles>.

Well, we already mentioned that particles are waves(excitations of the spacetime field). So then Maxwell describes how currents of waves produce regions of multiple waves of excited spacetime. And Lorentz would be describing how a region of excited waves interacts with incoming waves. Naturally fields and "particles" would interact directly because both of them are waves, the only difference being that particles are singular waves while fields(including as per OP's question) are nothing but collections(and/or currents) of waves.

Is this correct?

Anonymous Thu Jun 28 17:50:33 2018 No.9837008

>>9836966
a) Yes, I didn't mean to imply you think science is useless, but not applying it to build something new is useless.

b) Newton, Gauss, Euler, etc. They were all mathemiticians, physicists, philosophers (Newton was an alchemist). Back in the say, there was such little knowledge one could be knowledgeable in multiple fields. Now it is rare for a person to be a complete expert in their own field. There is too much to learn and catch up on, which is why you specialize in one thing and as you grow, you learn more about other subfields. Take an engineer for example. I'm sure he is a poor mathematician. He does not need to know about abstract algebra, topology, differential geometry, etc. He specializes in calculus, linear algebra, differential equations, as those are an engineer's every day life. Often times they cannot even solve the more interesting integrals by hand, but look up everything in a book or run a computer program to do it. This is not because they are lazy, but because they are specialized and need to get the simulations complete and numerical solutions. They are not interested in the various transformations and methods, they are interested in the results and how to use them for their problem. this doesn't mean we should all be this way, as that would be a very bad idea.

Anonymous Thu Jun 28 17:58:46 2018 No.9837017

>>9836988
I'm not sure it is known what causes it. The best answer I can really give is perspective. The coordinate system you are using in GR (space-time) becomes warped. SR is similar with having transformations between reference frames. This link briefly talks about (and shows the coordinates) for two reference frames and compares them:
https://www.quora.com/How-does-speed-cause-time-dilation
I may be mis-speaking when I say it is a perspective issue, but that is the best I have. Perhaps google would have a better answer.

Anonymous Thu Jun 28 17:59:39 2018 No.9837018

>>9836988
If one cannot answer the given question, you cannot expect any ordinary man to accept a ten page mathematical equation as an answer, even together with the experimental verification of the results. Do you understand what I mean?

"If you can't explain it simply, you don't understand it well enough." No need to specify where that comes from.

I do not even want a simple explanation, give me your most complex explanation, I will be thankful for any, as long as it is <causally logical>, because that is the only thing an ordinary man can be expected to understand. Every man builds logical constructs, this is how our brains work work, this is how we understand, you start from an apple hitting your head and reach a logical explanation of gravity. How would you go from running in the park to time dilation? How would you go from riding a car at 200mph and measuring light speed at c, driving at 2000mph and still measuring light speed at c?

The disconnect between the above and (math+observational evidence) is what I fear leads to dark ages.

Anonymous Thu Jun 28 18:02:30 2018 No.9837023

>>9836998
I'm not >>9836871 so I'll be brief. Each particle has its own field. An excitation of that field is the particle. Particles are not all excitations of space-time. The particle that would be an excitation of space-time is the graviton (particle associated with gravity that hasn't been scientifically found yet). I'll leave any further explanation to >>9836871

Anonymous Thu Jun 28 18:04:38 2018 No.9837027

>>9834000
Nobody has the first fucking idea and you'll find a couple of ways people have of coping with this:
(1) Ignore it and calculate and pretend the question of "what is it really" doesn't make sense eg >>9834020
(2) Pretend that we actually do have an idea and picture fields as some sort of star trek energy membrane eg >>9836567
We have no idea how anything works except at the most surface level and almost all of our physics so far is models. They're not bad models but not great and they get contradictory. Maybe when we become superintelligent AIs we'll have a better understanding.

>>	Anonymous Thu Jun 28 18:17:41 2018 No.9837042 >>9837023 I mentioned spacetime specifically because in a previous thread an "unknown" field whose excitations are our observable particles was mentioned. Then I asked why wouldn't we equate that field to the spacetime field?, but no answer was given.

Anonymous Thu Jun 28 18:19:16 2018 No.9837045

>>9836942
><mastery>
If you haven't played the board game Alchemists, I would recommend it. It is a summary of what it is like to do research in science (of course in a simplified way so the analogy and feeling only goes so far, but still worth playing). It is a fun game, even for non-researchers.

>>	Anonymous Thu Jun 28 18:20:42 2018 No.9837047 >>9837042 Not accusing, just straightening something before it goes too far or a misconception is built that all particles are excitations of the same field.

>>	Anonymous Thu Jun 28 18:22:29 2018 No.9837050 >>9834020 okay. what is the phenomenon being modeled

Anonymous Thu Jun 28 18:30:44 2018 No.9837059

>>9836856
from: http://www.emc2-explained.info/The-Light-Clock/#.WzVEj3D9gy4
"The mathematics are correct but the actual result is wrong! If it was correct it would mean that the pulse of light was travelling a total distance of 2 x 104,145 miles = 208,290 miles per second. It's a pulse of light, however, and can’t travel faster than 186,300 miles in a single second, nothing can"
What makes Einstein disregard the mathematically reached result in favor of the constant? Why doesn't he say, "Well the uppermost speed we have calculated with the moving light clock experiment is 208,290mps."?

Anonymous Thu Jun 28 18:34:41 2018 No.9837066

My favorite analogy is to think of fields as sheets, and to think of particles as places where those sheets have bunched up and created little mounds. When this happens, the area of a sheet around a cluster of mounds gets stretched (explaining relativity). In this sense, the mound IS the sheet just as the particle IS the field. But what is the field? Well, it's sort of like a sheet. But 3 or 4 or more-dimensional. Anyway that's my brainlet way of thinking about it. Please correct if it's just wrong

Anonymous Thu Jun 28 18:46:35 2018 No.9837092

>>9837059
Maxwell's equations. The speed of light is a constant value. The link below shows Maxwell's equations without any sources (no charge density or current density). I'm not sure of your level of mathematics, but you may be able to follow a bit of it at least to get to the expression for c (top boxed equation page 2)

http://srjcstaff.santarosa.edu/~lwillia2/42/WaveEquationDerivation.pdf

In order to keep it a constant in both reference frames (since the other postulate is that the laws of physics are the same in all reference frames) there must be dilation. If he decided to toss out the constant value for speed of light, then he would have to have rationalized why not to trust Maxwell's equations and come up with something else. Because of how fundamental Maxwell's equations are, he held them true. Similar reason to why we hold true the concepts of conservation of energy and momentum.

>>	Anonymous Thu Jun 28 18:47:22 2018 No.9837093 >>9836995 >QFT >We know what causes fields ooh I know I know. The answer is 'the multiverse!' What did I win?

Anonymous Thu Jun 28 18:52:34 2018 No.9837100

>>9837093
Admittedly, when I said we know what causes fields, I had in mind classical fields like electric fields caused by charges or magnetic fields caused by dipoles or currents. If you are looking for what causes the Higgs field or another field in which the excitation is the particle, yes, then we do not know for the same reason we do not know what causes an electron to exist or any matter to exist. It is, we model it and its interactions, may be able to provide a mechanism of how it was partially generated, but that is all.

If you are going to go have an existential crisis, that will never end.

>>	Anonymous Thu Jun 28 18:59:30 2018 No.9837110 >>9836642 >field of water >field of _______ (what)

>>	Anonymous Thu Jun 28 19:03:40 2018 No.9837114 >>9834000 What is distance physically?

Anonymous Thu Jun 28 19:09:03 2018 No.9837122

>>9837100
The clearest explanation of all the confusion around this that I've read was the Stanford Encyclopedia of Philosophy entry on Nothingness and the silliness of asking "why is there something rather than nothing."

The simple answer is that it is just not possible for there to be nothing, as evidenced by the existence of something. Our abstract notion of Nothingness creates the confusion. Infinity is more concrete "in reality" than Nothingness is.

https://plato.stanford.edu/entries/nothingness/

>>	Anonymous Thu Jun 28 19:10:06 2018 No.9837124 >>9837114 What is the thing being measured?

>>	Anonymous Thu Jun 28 19:10:41 2018 No.9837126 >>9837124 Distance. What is it?

Anonymous Thu Jun 28 19:12:16 2018 No.9837129

>>9837122
Yeah, that's just an ex post facto answer of we see something so we have to have something. Since there is something, we should be able to have a mechanism though. That's like asking why we have 4chan. It's a non-sense questions because we do, it just skirts the question.

>>	Anonymous Thu Jun 28 19:17:03 2018 No.9837138 >>9837129 Well, it goes much more in depth than that. I was just giving a microsummary and highly recommend reading it

Anonymous Thu Jun 28 19:18:00 2018 No.9837142

>>9837124

It doesn't matter. The point I'm trying to make is that distance is an abstract quantity just like a field, but we happen to grow up with an intuitive notion of it. It's not on firmer logical ground.

If some alien came from a universe with no spacetime and asked you, 'what is a distance?' or 'what is a length?', how would you explain it without using self-referencing examples?
Fields are sort of in that same predicament...

>>	Anonymous Thu Jun 28 19:21:49 2018 No.9837147 >>9837142 It matters to me. I understand the knowledge I want is inaccesible, and mechanisms, distances and models is all we can ever glean. But I still can't help wanting to know

Anonymous Thu Jun 28 19:35:55 2018 No.9837162

>>9837147
I meant it doesn't matter what you're measuring. Asking 'what a field is?' is a question that should be asked and does matter.

The best answer I can give though is that quantities are defined by how you measure them.

If I wrote down Maxwell's equations and didn't tell you how electric or magnetic fields act on particles, then my theory and the fields I told you about are completely meaningless. I could make up something called a super-duper field and give you all this cool complex dynamics it has, but until I define this field through how it effects measuring devices or relates to some already well defined quantity, it also has no predictions and is meaningless.

Distance is meaningless until I introduce a ruler as a standard of measure and use it to start declaring lengths of things. Force and mass don't mean anything until I introduce newton's laws.
Fields are just another abstraction like these.

>>	Anonymous Thu Jun 28 20:00:21 2018 No.9837193 >>9837092 Thank you! Imma have to go to bed now, but will investigate the link, till later!

>>	Anonymous Thu Jun 28 20:01:06 2018 No.9837195 >>9837110 not field of water field of (You)

>>	Anonymous Thu Jun 28 20:10:09 2018 No.9837204 >>9836518 >There is no way to internally define a system of axioms Someone here gets it

Anonymous Thu Jun 28 21:43:09 2018 No.9837332

>>9837162
You are claiming some pretty strong philosophical points. You have to consider exactly how are you understanding "physics". Theorettical models can be developed through math, and so you can define shit by using mathematical definitions. For many objects it's clear that that just pure mathematical models are too abstract to understand the underlying physics. This is clear with problems of inerpreting models in quantum theory and relativity. But the notion of "distance" while it may be inspired by our intuitive notion of euclidean geometry, we still have definitions that supersede those ideas, or at least in other philosophical positions. A more platonic view makes the idea of defining everything as "the universe is a four dimensional affine space which has an euclidean structure" more easy to state as some unviersal notion.

>>	Anonymous Thu Jun 28 21:48:09 2018 No.9837339 >>9834062 The area of influence that is created by mediator particles.

Anonymous Thu Jun 28 23:36:39 2018 No.9837471

OP here. so from what i'm gathering the notion of a field is an abstraction, but if particles are excitations in a field, then what ARE these particles not from a modelling standpoint but from a causal standpoint? what makes a particle an excitation in a field? what makes us a collection of fields and their interactions, and what makes this whole notion of fields something that is physical and capable of producing forces, ATP, life, etc. it's odd to me. am i just a big group of nothing that happens to produce conditions to absorb and emit field excitations?

>>	Anonymous Thu Jun 28 23:45:47 2018 No.9837487 >>9837471 String theory senpai

>>	Anonymous Thu Jun 28 23:49:11 2018 No.9837493 >>9834000 http://www.ehu.eus/aitor/irakas/mes/Reference/mermin.pdf

Anonymous Fri Jun 29 00:02:59 2018 No.9837510

I can get behind a philosophical debate about what is real, what is a construct or abstraction, and what is a representation or approximation. Whatever words you'd like to use to show the meaning of what is actual compared to what is imposed. My question is, at the end of the day, what does that knowledge change? If nothing, fine, then let's just continue for the pleasure of exercising our minds; but if for something more, then what?

Anonymous Fri Jun 29 08:15:12 2018 No.9838023

>>9837332
>A more platonic view makes the idea of defining everything as "the universe is a four dimensional affine space which has an euclidean structure" more easy to state as some unviersal notion.

Even when you have a structure that tells you relationships between quantities, these quantities still mean nothing until you tell me how to measure them.

When you measure an object with a ruler and declare it to be a certain length, you are only comparing those two objects and defining the length in terms of each-other. How do you know that both objects aren't shrinking, or both objects aren't growing? Or that both objects are the same size in one location v.s. another location? We don't have to worry about all these considerations once we DEFINE a measure of length by saying "something is such and such long if bring up a ruler and see that it covers such and such tic marks", and perhaps of observe that the resulting space is Euclidean.

>>	Anonymous Fri Jun 29 08:17:40 2018 No.9838029 >>9838023 The idea of a "metric" or "riemannian metric" has no meaning unless you have an apriori way to measure them?

>>	Anonymous Fri Jun 29 08:21:36 2018 No.9838032 >>9837471 Tsk tsk tsk. Don't listen to these turds on here. Listen to Sean Carroll. Particles are more the abstraction, not fields. These backward Neanderthals are undoing years of study. Don't listen to them. They're just regurgitating 1950s popsci.

Anonymous Fri Jun 29 08:27:08 2018 No.9838038

>>9837471

Do you know any quantum mechanics? If so you'd know that for bounded potentials, you'll have a discrete energy spectra v.s. classical where particles have a continuous spectra (can have any energy lower than the energy to escape the potential)

In non-relativistic quantum, usually you are given potential energies that depend on the position of the particle. In QFT, you are typically given potential energy in terms of the fields. Particles are like your energy spectra existing in this more abstract field space. Classical field theory wouldn't have particles, just blobs of field that could take on any value.

>>	Anonymous Fri Jun 29 08:28:58 2018 No.9838045 >>9838029 Mathematically? Yes. Physically? No.

>>	Anonymous Fri Jun 29 08:37:34 2018 No.9838050 Why is science so hard?

>>	Anonymous Fri Jun 29 08:40:25 2018 No.9838054 >>9838045 Why? Physics uses math to express what could potentially handwavy ideas. Are you saying that units of measurements are arbitrary? Well no shit.

Anonymous Fri Jun 29 08:58:48 2018 No.9838076

>>9838054
No, not just units. The idea of the physical quantities themselves are just words unless you tell me how to measure them.

Mathematics doesn't automatically make things more precise. Writing down a bunch of equations is also 'just words' until you tell me what the variables in each equation means. It's only the union of the definition of these variables and their relation to each-other in the equations that I impart non-trivial information about the physical world to you.

>>	Anonymous Fri Jun 29 09:45:49 2018 No.9838127 >>9838076 Out of curiosity, how old are you?

Anonymous Fri Jun 29 10:01:35 2018 No.9838148

>>9838076
The idea of length dimensions are based on basic empirical information we get from our sight and movment in 3D space. Time is based on causality and movement also. Mass on the motion of stellar bodies and on the fact that pushing shit is hard etc... No, the physical measurments define the empirical process as "scientific" in some sense, but these ideas have existed even before newton.

Anonymous Fri Jun 29 10:52:05 2018 No.9838201

>>9838127
Why?
25

>>9838148
>The idea of length dimensions are based on basic empirical information we get from our sight and movment in 3D space
Agreed.

>No, the physical measurments define the empirical process as "scientific" in some sense, but these ideas have existed even before newton.

Sure, but just because a concept has been around awhile doesn't mean it's precise or that everyone has a strict consensus on what you're saying.

Yes, science is when you empirically test the relationship between quantities that are defined by a measurement. You can't test a definition.

If I define quantity A by the number of dashes that show up on a screen, and I define quantity B as a number of tic marks on some device, then I could hypothesis a functional relationship between A and B, f(A)=g(B). The science would come in me testing if f(A)=g(B) holds, but it doesn't make sense to ask "is A really the number of dashes on the screen?", because I said it was by definition.

Anonymous Fri Jun 29 15:40:13 2018 No.9838693

>>9838201
then you're setting up a model using an axiom by stating that the means of which you measure is done using a dash. but in this case suppose someone asks you not if it really is measured using dashes, but what a dash is. if you say it's just an abstraction, that's fine if it bears no influence, but for something like a field, it isn't that simple.

Anonymous Fri Jun 29 17:13:21 2018 No.9838842

>>9838693
>then you're setting up a model using an axiom by stating that the means of which you measure is done using a dash.

The quantity "A" is more than just a "means to measure using a dash." It IS the number of dashes.

> but in this case suppose someone asks you not if it really is measured using dashes, but what a dash is

What is a dash? A dash might look like "/" on the computer screen, and it terms of the model it's one unit of quantity "A". There is no explanation for what a dash is, although if my hypothesis was correct (f(A)=g(B)) and I happened to have a more intuitive notion of what quantity "B" is I could content myself by saying that a dash is one unit of f^-1(g(B)).

>if you say it's just an abstraction, that's fine if it bears no influence, but for something like a field, it isn't that simple.

Not sure what you're getting at here. In a certain sense QFT is formulated using quantities that we have much less intuitive notions of, yet at every step can be defined and related to more pedestrian quantities we might dare to call "observables". There's nothing more intrinsically fundamental about time or length than fields or actions, but we all apparently have more consistent and shared delusions of what a distance is. It's apparently a quantity that we all have standardized notions and measures of, and is often simply accepted as a final answer without the same scrutiny and questioning given to quantities like fields.

Anonymous Fri Jun 29 17:29:45 2018 No.9838876

>>9837018
Everyone looks for different answers to the same questions. I often find people cannot explain concepts well then when I understand it I have a quick analogy that makes sense, but it's good for me and not others. If you want a proper answer to your question, study the and understand the mathematics. When you do, then you can go back through looking at only the concepts used and keep breaking it down into as simple terms as you'd like. Other people will not explain relativity in your language and terminology, especially if your terminology differs drastically from common science.

Anonymous Fri Jun 29 17:31:59 2018 No.9838882

>>9834090
>sigh
>what is the physical phenomenon
>that the meme called 'field' is modeling

I'll answer this honest question.

The energy mechanics are directed by local photonic spin interactions.
The meme called 'field' is a model of the affects of certain coherent photon spin locations.

Anonymous Fri Jun 29 17:36:36 2018 No.9838894

>>9838201
Was just curious because I've heard many of these conversations from high school students, but they were never refined enough to 1. Hold the conversation beyond the first statement 2. Have an interest or ability in the deeper mathematics and 3. Be well spoken. Although it seems to have little progress on either side and much more interpreting words and meanings, it has been a worthwhile conversation contrary to first anticipated.

>>	Anonymous Fri Jun 29 17:39:12 2018 No.9838898 >>9838882 Fields apply to more than photons and spin.

>>	Anonymous Fri Jun 29 18:02:49 2018 No.9838953 >>9835089 Because it leaves our curiosity unsatisfied. People want to know what's really there almost as much as they want successful predictions.

>>	Anonymous Fri Jun 29 18:12:41 2018 No.9838983 >>9834000 A field is just a region where a force is exerted without contact. For example, the area near a massive object or a point charge is a field.

Anonymous Fri Jun 29 18:23:49 2018 No.9839006

>>9838894
Thanks, and glad you got something out of it.

I agree that these conversations are difficult, but I still think they're important to think about, especially for education. "What is a field?" is a very natural question; one that many students new to the subject often have and cannot find answers for that they consider satisfactory. Combine this question with the lack of knowledge and vocabulary needed to better articulate this confusion and you'll generate burned out students who learn that their natural thought process must be suppressed in order to solve some math problems.

Although I suppose I might be projecting and the people who can't shut up that little voice that won't stop asking "But what is a field?" even after they learn all the math end up in grad school.

Anonymous Fri Jun 29 19:16:35 2018 No.9839060

>>9839006
Yeah, I agree there is an issue with the "shut up and calculate" mentality. In my experience, people usually reword your question or say a better question is... That happen 3d when I asked what is light and the professor said a better question is how does light behave? Then shared the knowledge of that. He had a point that (not too dissimilar to yours) that abstract models and debating whether light is a wave or a vibration of a field or thought of as a particle is irrelevant. Better to know what you can actually do with it since that is where the important consequences are. It does leave the mind a bit frustrated, but at least shares some (hopefully new) knowledge. As said before, best to accumulate the knowledge yourself and answer the questions you once had. Maybe you'll come across someone with the same questions and can give them more help with their search for answers.

>>	Anonymous Fri Jun 29 19:17:59 2018 No.9839064 >>9839006 These conversations are usually best over lunch face to face, but alas, 'tis the day of the internet.

>>	Anonymous Fri Jun 29 20:00:25 2018 No.9839102 Issa blanket with legs or half-legs

Anonymous Fri Jun 29 21:35:14 2018 No.9839253

>>9839006
From what I know of quantum anything, even the most famous physicists openly say they are as confused as anyone by what the quantum world actually means. So wether you're a famous physicist or an undergrad, all you can really do is shut up and calculate

Anonymous Fri Jun 29 21:41:39 2018 No.9839269

>>9834090
>>9834069
What is the physical phenomenon that makes a herd?

I suppose in that case, the answer would be a bunch of cattle, and the social dynamics that make them form a herd.

In this case, it's a bunch of particles, and the dynamics that cause them to interact the way they do.

Assuming you're talking QM. Bit different in relativity and the colloquial - in which case it'd be what the herd is grazing on.

Anonymous Fri Jun 29 21:43:10 2018 No.9839275
File: 47 KB, 640x429, 1442387654.jpg [View same] [iqdb] [saucenao] [google]

>>9838898
magnets, like all matter, are channel energy through their atoms, sub atom particles called photons. The coherent chirality of the photons as the exit the magnet is the field.
Think about the faraday disk, the magnet is a key part of pushing the electrons yes, it's the force exert by the photonic field emitted from the magnet that excites the electrons and pushes them. Electricity is not actually electron flow, it is photon flow, (energy flow,) the photons coherency in the magnetic field catches valence electrons of the conductor and like a bunch of ping pong balls in a river, the electrons are carried away by the flow of photons.
A static field is a different beast with a different structured coherency of spinning photons being emitted.

>>	Anonymous Fri Jun 29 21:45:51 2018 No.9839279 >>9839275 channeling subatomic

>>	Anonymous Fri Jun 29 22:20:09 2018 No.9839338 >>9839275 Obvious bait is obvious.

Anonymous Fri Jun 29 22:50:25 2018 No.9839382

Disregarding all the brainlet and rp posts....

You can show with maxwell's equations the energy is carried transversely by orthogonal em waves.

Magnetism though is just a relativistic electric interaction.

Every electric field has a source charge.

Therefore, em, light, and respective fields all boil down to charge distributions. At the time, and even after sr, aether was still sought after, and fields as perturbed aether was the goal. Now that aether is not part of the standard model, fields have pretty much fallen in to disuse, except when taught in university undergrad where you literally learn 200 year old physics.

You can talk about fields insofar as to discuss their sources, but you cant interact with fields directly or measure them. They are neither necessary nor physical in describing an actual system.

>>	Anonymous Fri Jun 29 23:47:19 2018 No.9839440 >>9839275 Ignoring everything you said about those and not using them as examples, how about a general force field? Gravitational field? Any individual particle's field beyond photos?

Anonymous Sat Jun 30 00:56:05 2018 No.9839525

I think the best way to discuss this is to first understand that we will never truly know "what" something like a quantum field is, only the rules that can probabilistically reason from observation.
Therefore unless we can disturb the global properties of a field, we can only understand it from a local (internal) viewpoint and never know it in its entirety.

>>	Anonymous Sat Jun 30 00:58:16 2018 No.9839530 >>9839440 A shit ton of energy thrown into a particle accelerators (smaller old style spiral one I forget the name of) shoot a web of ion beams, maybe try to connect the dots and recycle ions between accelerators.

>>	Anonymous Sat Jun 30 01:02:08 2018 No.9839532 A bunch of mini 21st century cyclotrons.

>>	Anonymous Sat Jun 30 01:16:05 2018 No.9839553 >>9835278 kek

>>	Anonymous Sat Jun 30 01:51:18 2018 No.9839602 File: 66 KB, 900x452, apada.jpg [View same] [iqdb] [saucenao] [google] >>9834090 imagine a body of water, you swimming in it, your field is the disturbance on the water cause by your act of swimming

>>	Anonymous Sat Jun 30 03:15:45 2018 No.9839730 >>9839602 then what is the water????

>>	Anonymous Sat Jun 30 10:00:51 2018 No.9840126 >>9839730 spacetime

>>	Anonymous Sat Jun 30 10:10:36 2018 No.9840131 File: 166 KB, 400x400, thats.png [View same] [iqdb] [saucenao] [google] >>9840126

>>	Anonymous Sat Jun 30 12:47:06 2018 No.9840331 >>9839730 irrelevant

>>	Anonymous Sat Jun 30 14:24:22 2018 No.9840488 >>9839730 an electric field is just the area of disturbance caused by the electron spinning very fast

>>	Anonymous Sat Jun 30 14:35:00 2018 No.9840504 >>9840331 how is it irrelevant if you can't propagate something in nothing? wouldn't it violate conservation laws?

>>	Anonymous Sat Jun 30 15:02:32 2018 No.9840546 >>9840126 Spacetime would seem to be just one (graviton) field.

>>	Anonymous Sat Jun 30 15:03:33 2018 No.9840548 >>9840546 I.e. the one field this thread is NOT about

>>	Anonymous Sat Jun 30 15:05:27 2018 No.9840553 >>9840331 >i really don't care, do u? Science, summed up in one jacket

>>	Anonymous Sat Jun 30 15:22:35 2018 No.9840593 >>9840553 mehlania

>>	Anonymous Sat Jun 30 15:26:03 2018 No.9840601 >>9836392 Rings always have 1. All other conventions are shit.

Anonymous Sat Jun 30 15:42:17 2018 No.9840622

>>9840504
vaccuum is not void, don't confuse the two. As far as we know there is no such thing as a true void in the universe, therefore we have nothing to compare it to. Vacuum is just the least dense thing we know of, but that does not mean it does not have density.

Anonymous Sat Jun 30 17:03:45 2018 No.9840728
File: 1.99 MB, 350x189, 1529883339875.gif [View same] [iqdb] [saucenao] [google]

>>9836215
>spinor fields
Autist doesn't realize that engineers are the ones who take mathematics and physic revelations and make practical use of them rather than relegate them only to theory. . .

>>	Anonymous Sun Jul 1 09:56:23 2018 No.9841853 >>9836215 Engineers don't care, they just want to make nice bridges and set [math]\pi = 3[/math]

>>	Anonymous Sun Jul 1 12:48:47 2018 No.9842115 File: 11 KB, 509x351, Dd4eU3gVQAIAL0j.jpg large.jpg [View same] [iqdb] [saucenao] [google] >>9836215 >>9836215 >>9840728 >doesn't realize spinor is a generalization of quaternions, which is a genealization of complex numbers

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/sci/ - Science & Math