PBS Spacetime has a fantastic video on the Higgs Field that explains it about one level deeper that typical pop science, and answers some of the questions I'm seeing in this thread, include "why did the field switch on suddenly?" and "Why is the Higgs Field different from other fields"
I can also add this set of articles from Matt Strassler which explains it all with surprisingly simple math. It really is quite understandable and I wish more pop-sci discussions of the subject threw in a few equations now and then to explain such stuff.
If anyone wants to dig deeper, there is an excellent lecture on YouTube by Leonard Susskind. This goes into some details on how fields in general give mass to (composite) particles, and how the Higgs field has certain properties that allow it to give mass to elementary particles. It goes only into a tiny bit of math, absolutely intelligible at the high-school or at least undergraduate level.
> Once upon a time, there came into being a universe. Searingly hot, it swarmed with elementary particles. Among its fields was a Higgs field, initially switched off. But as the universe expanded and cooled, the Higgs field suddenly switched on, developing a nonzero strength.
Any particular reason/mechanism why the Higgs field suddenly (gradually?) switched on?
> Any particular reason/mechanism why the Higgs field suddenly (gradually?) switched on?
"Switched on" is not really a good description. According to my understanding of our best current model, the Higgs field was not in its vacuum state in the very early universe--there were lots of Higgs particles around--so it was not "switched off" any more than any of the other Standard Model fields were. But in the very early universe, the electroweak interaction worked differently than it does now. As the universe cooled, there was a phase transition that changed how the electroweak interaction worked, and after that phase transition, the Higgs field acquired what is called a nonzero "vacuum expectation value", meaning that even though there were no longer any Higgs particles around-- the Higgs field was in its vacuum state--that vacuum state now corresponded to a nonzero value of the Higgs field, meaning that the field can interact with other fields, and that interaction is what we observe as mass for those other fields.
It is believed to be the cooling of the universe. At ridiculously high temperatures, such that have not existed since the first fraction of a second of the universe, the electroweak symmetry was broken and most physics we are familiar with didn't work. Unfortunately the math behind it is way over my head so that's about all I can say on it.
My understanding: The Higgs field, uniquely, has a nonzero vacuum expectation value -- so, when it's in its ground state, it's "switched on", it has an effect. In the early universe, it was in a higher energy state; for most fields, that would cause them to have an effect, but for the Higgs field that instead allowed it to take on a zero vacuum expectation value and to be "switched off". The Higgs takes on nonzero values at low energies instead of at high energies like other fields, so it "switched on" as the universe cooled.
If the higgs field did not exist, particles would not have enough mass to attract each other, and the universe as we know it would not exist.
So while I do not know if there is some particular cause of the higgs field, no reality like ours would exist without it, and realities without it would not look like anything we recognize (although maybe scientists could simulate it).
tldr is that it happened because the universe cooled down from a stupendously insanely high temperature to a merely insanely high temperature shortly after the big bang.
The Higgs field is a complex number Φ (this number can vary at different points in space, we'll come back to this, so don't worry about it for now). You can imagine it as a ball bouncing around on the landscape shown in the image. The higher the altitude of the ball, the more energy it has (just like a ball in real life). Φ = 0 corresponds to the center of the image, the point right at the top of the little hill.
At a high temperature, the ball is jostling and moving around like crazy. You can imagine constantly pelting the ball with marbles from all directions, causing it to dance eratically around the landscape. (Further, the ball doesn't experience any friction. It slows down when it happens to get hit by a marble that's heading in the opposite direction to it.) In reality, there are no marbles, of course, the jostling comes from the interactions of the Higgs field with other fields, all of which are also stupendously insanely hot.
The landscape in the picture has a rotational symmetry. You can rotate it by any angle, and it will still look the same. When the temperature is very high, the ball dances across the whole landscape. It slows down as it climbs up a slope, so it does spend less time at the bits that are at a higher altitude. But if we consider a thin ring around the center that's all at about the same altitude, the ball is equally likely to be anywhere along the ring. The average value of Φ is 0.
As the temperature decreases, the ball's motion calms down, and it spends more and more of its time in the deepest valley of the landscape. It rarely has the energy to climb high up the slopes anymore. Eventually, the ball will start to live on just the narrow ring around the center where the altitude is lowest.
Now we come back to the fact that the Higgs field is a field, which means it has a value at every point in space, and these values can differ from each other. It turns out that all fields in physics "prefer" to have similar values at nearby points in space. There is an energy penalty for fields that change rapidly in space. At high temperature, this didn't matter too much. The Higgs field had lots of energy to pay this penalty, just like it had lots of energy to climb up the slopes of the landscape. So the field here and the field 1nm to the left could have wildly different values. At cold temperatures, it matters a lot. So the Higgs field has the lowest energy if it has the same value everywhere in space. Anything else comes with an energy penalty. If we pick a point in space, and try to move the field clockwise or counterclockwise around the center, the neighbouring points in space pull the field back towards the average of the surrounding values.
So at any point in space, Φ is just equal it its average value, which is not 0. It's not zero because we have to randomly pick a point somewhere along the ring of lowest altitude, which is some distance from the central 0. The universe has randomly selected a direction in this landscape to be "special".
This is the situation from when the universe was insanely hot all the way up until the present. Incidentally, if you vibrate the ball radially, towards and away from the center of the landscape, this vibration corresponds to the Higgs boson.
If we could somehow heat the universe up to a stupendously insanely high temperature again, then the special direction would disappear, and the average of Φ would be 0 again. This is kind of similar to how magnets lose their magnetization if heated past a certain critical temperature, the Curie point. [1] If we let it cool down again, it would choose a different random special direction.
Imagine some preindustrial scientist being awakened in the modern era to find that the aether has been first debunked for more than a century and then rediscovered, but with different rules.
Rule #1 of talking about the aether is "don't call it aether".
Nowadays it's "spacetime this" and "mass-energy tensor that" and "properties of vacuum something else".... and we still end up with empty space behaving like a funky fluid.
It's not an aether... I mean, aether was a crutch, but the mathematics that Lorentz developed simplified and you just don't need aether -- it's enough to assume that there's a maximum speed of light and the relativity principle.
(Well, that's only true if you assume there's no as-yet undiscovered fields and particles with FTL that we could eventually interact with -- then we would be able to get something like measurements of speeds of everyday particles and photons relative to such fields, and if they were much faster than light then those measurements would look like "absolute speed" to us. But that's sci-fi fantasy.)
Higgs is not aether for electromagnetic waves. It's only a wee bit like aether for matter if you squint real hard, but still, it's not a medium of travel for matter, so it's not an aether.
As a lay person, I found that a clear and understandable explanation, which in my experience suggests it is a wild wild over simplification - but enjoyable nonetheless
A question for the more expert amongst you. Is the Higgs field unique in its interaction with other fields, or are there other similar fields which similarly change the way that other fields (and associated particles) behave?
I’m not a qft-ist, but from the top my head the Higgs field wouldn’t explain the (likely positive) mass of neutrinos. So there could potentially be another mass creation mechanism. But someone else more informed could clarify.
Layman trying to wrap my head around this: the Higgs field causes other fields to stiffen by giving them a resonant frequency, with higher frequencies meaning more mass.
Hmm, now this is making me think, does the Higgs field act like an additional degree of freedom for energy to be dumped into? I mean like a photon is massless, so any amount of energy, it will already be going the speed of light so the only place where additional energy to go into is the frequency. Perhaps with massive particles, a portion of this additional energy now gets dumped into this resonant frequency rather than translating into motion? So the energy stored in this resonant frequency would be like the kinetic energy...? or maybe totally wrong :)
So to conceptualize the difference between fields with and without restoring forces, I imagine that, for a field that doesn't have a restoring force, the medium itself can move permanently. For example if you have just a bunch of ball bearings lying on the surface of a table, you can cause a wave to go through the balls by hitting one. One bumps into the next, which bumps into the next, etc. There's no restoring force, so the wave is moving through the balls, and the balls are actually moving into a new position and they stay there.
Compare that to a water wave, where gravity is trying to restore the particles to a "flat" position in space. If you cause a wave in water, the medium will return to the space it occupied before through the restoring force, even as the wave travels through it.
Is this really how it works, so that e.g. the EM field itself can move in space, whereas e.g. the electron field cannot move in space, it's "pinned" in some sense by the Higgs field?
First, worth noting that "the EM field" (the thing that shows up in the wave equation) in this case is specifically the EM 4-potential. This doesn't work if you try to treat "the EM field" as the strength of the E and B fields or something - it has to be the 4-potential. I got tripped up by this at one point
Second, this isn't pinning the field in space, it's pinning the magnitude of the field to be close to some value (probably you can call that value 0)
So if the field locally gets "too high" or "too low", there's a restoring force accelerating it back towards the "normal" value, like a spring attached to the normal value.
It's not pinning it in the sense of stopping translation through space or time
In the water wave analogy, we're using the vertical dimension to represent the magnitude of the water wave, but translating that to other contexts, we're not literally talking about a physical height, just the magnitude of the field. (Which, for all I know, maybe you can formulate that as a position in some higher-dimensional space or something)
> A common approach has been to tell a tall tale. Here’s one version: There’s this substance, like a soup, that fills the universe; that’s the Higgs field. As particles move through it, the soup slows them down, and that’s how particles get mass.
Is that really so? I've never heard this analogy, so the whole premise seems a bit of a straw man...
> By suggesting that the Higgs field creates mass by exerting drag, they violate both Newton’s first and second laws of motion.
Personally, I've wondered why theoretical physicists don't dive into Newton's laws more. Ever since I was a kid and first learned about the Voyager probes continuing to move through space forever, my question was why??
All matter is energy, and energy is vibrations in quantum fields, and that vibration never stops (you can never reach absolute zero). From the smallest gluon bouncing between quarks to galaxies to the expansion of the universe itself, matter never stops moving. Where does this infinite source of energy come from?
I understand that physics simply describes how reality works, not why, but I think it'd be valuable to know the reason fields continue to vibrate forever.
I studied wave mechanics in college, but the origin of mass didn't click for me until several years later (and in fact I don't believe it was every brought up in the context of wave mechanics, which seems like a problem in retrospect). The conceptualization that worked for me is this:
The normal wave equation is (ignoring constant factors like mass and propagation velocity):
d^2/dt^2 f(x,t) = d^2/dx^2 f(x,t)
<acceleration> = <pulled towards neighbors>
This says "if a point in the field is lower than its neighbors, it will be accelerated upwards. If a point in the field is higher than its neighbors, it will be accelerated downwards." This equation is the lowest-order description of most wave phenomena like sound waves, water surface waves, EM waves, etc. and it's usually pretty accurate.
If you look for solutions to this differential equation, you can get
f(x,t) = exp(i * w * (x±t))
w is the frequency of the wave
This tells you that the frequency and wavenumber of waves is determined by the same parameter (w), so they are proportional to each other
Now, what if we add a restoring force to this equation? This is a force that pulls the value of the field towards zero.
d^2/dt^2 f(x,t) = d^2/dx^2 f(x,t) - M^2 f(x,t)
M is just a parameter that tells you the strength of the restoring force. The force increases as the field gets farther from zero, like a spring.
Now, solutions to the equation look instead like
f(x,t) = exp(i*k*x ± i*w*t)
Where w^2 = k^2 + M^2
(or something like that, I need to re-derive this on paper, just going off memory, but I think if you plug it in it should work)
Notice that now, if you have a spacial frequency k, your temporal frequency is actually higher. In fact, if your spacial frequency k is 0 (corresponding to a stationary wave), your temporal frequency is still M!
This is what mass is. Having a non-zero frequency even if the wave is the same everywhere in space (which corresponds to no movement)
A field with no restoring force is e.g. the EM field, so photons are massless. The rate at which they oscillate in time is the same rate at which they oscillate in space. A massive particle has a restoring force, so its temporal frequency is higher than its spacial frequency.
In physics, this equation is often reordered like this:
d^2/dt^2 f(x,t) - d^2/dx^2 f(x,t) = - M^2 f(x,t)
(d^2/dt^2 - d^2/dx^2) f(x,t) = - M^2 f(x,t)
(d^2/dt^2 - d^2/dx^2) f(x,t) + M^2 f(x,t) = 0
◻ f(x,t) + M^2 f(x,t) = 0
(the d'alembert operator)
(◻ + M^2) f(x,t) = 0
Again, this is ignoring constant factors like c, h, etc.
The above equation is nice because it's relativistically invariant. The d'alembert operator is the contraction of the 4-momentup operator with itself, p^u p_u. This is a concept worth studying - tells you a lot about what mass, energy, velocity, and momentum actually are in a general sense
> The rate at which they oscillate in time is the same rate at which they oscillate in space.
Wouldn't it be the opposite, that they do not oscillate in time at all so that they oscillate in space as rapidly as possible (since, as we know, time doesn't pass for photons)? And stationary particles don't oscillate in space, so they oscillate in time as rapidly as possible. Or are you using "oscillate" in a different sense here?
> Quantum field theory, the powerful framework of modern particle physics, says the universe is filled with fields. Examples include the electromagnetic field, the gravitational field and the Higgs field itself. For each field, there’s a corresponding type of particle, best understood as a little ripple in that field. The electromagnetic field’s ripples are light waves, and its gentlest ripples are the particles of light, which we call photons.
What are these fields made of? Are all fields made of the same thing(s), or is each field made differently?
The book Waves in an Impossible Sea really goes into some depth on this (for a layman -- which I am) and tries to drive home the point that there are two perspectives one might take. There's the perspective of the medium and the perspective of the field.
Using wind, as an example, we can measure the wind speed/direction at various points in a given space. We don't need to know what wind is to feel its effects. Instead, we might view it as a force wave that propagates through space and interacts with everyday objects. The measurements of this force that we take at various points in space across a given area form what we might call the Wind Field. We don't need to know the nature of the medium these wind waves propagate through in order to study wind and how it interacts with other objects. This is the field perspective.
Of course, we know that wind is really an effect of air molecules moving through space. That is, the medium for wind is the atmosphere. This gives us deeper insight into what wind is and how it works. This is the medium perspective.
According to the book, we don't know what the media for the elementary particles are or if there even are any. Our intuition based on waves that we see in everyday life tell us that there must be some medium through which the wave can propagate, but thus far we have found no such medium for waves such as light.
We just know there are measurable properties that we can measure across points in space and we have created mathematical objects (fields) to represent this. From there, we can construct theories and make predictions based on these models.
Afaik, the official answer is that they are made of nothing because they are fundamental. That's how scientists say "we don't know". But when a fridge magnet sticks to a fridge, something holds it there and it's not nothing. It's not photons either. It's the magnetic field itself, the one that's made of "nothing". Photons are like waves in the magnetic field "water", but water isn't made of waves. Equations of magnetic field have a curious similarity with the flow of something in 4 dimensions (I mean that kaluza-klein theory), but nobody has managed to make that theory work yet, so there must be something else. Iirc, Einstein himself spent half of his life on this idea, but didn't succeed.
I think that’s a tricky question. In one sense, they aren’t made of anything since they are elementary fields. Meaning they don’t have constituent parts. But one could still argue that it’s relevant to say that they are of some kind of substance in a sense. The nature of that substance is the domain of Theories of Everything and some argue that the discussion becomes either purely mathematical or somewhat philosophical in nature, more so than a matter of physics anymore. For example, some argue that the fields are all made of math, so to speak, or likewise that their differences are like geometric variations on the same substrate.
Fields aren't made of anything. When you feel static electricity, like when you rub a balloon against your hair, and your hair then stands up, that electric charge on the balloon and your hair is somehow being made evident across the space between the hair and the balloon. That communication of force electric charge happens over the electric (really, electromagnetic) field. It happens across air and vacuum alike. Nothing need be between the charged objects and yet the charge will be "felt" by them. That "field" is just the numeric electric charge felt at each point in space, for all points in space. It's just field strength -- a bunch of scalar values, one for every point in in space. We call that a field, but it's not an object made of stuff, just a mathematical object.
I always thought the fields are just the mathematical representation of the respective force carrier particles travelling through space. Such particles (the photon is certainly the most relevant for us) are having such a big size due to their statistical nature that the fill space even though their own size when probed is tiny.
And "the Higgs field suddenly switched on" is analogous to the pendulum's random vibrations slowing down enough that they no longer overwhelm its pendulum behaviour?
Very nice explanation by Matt Strassler. I am not sure it is possible to do better without getting into the details of quantum field theory.
For those who know quantum mechanics I would add that the oscillations mentioned in the article are just the familiar exp( i E t ) of any wave function that is an eigenfunction of the Hamiltonian. For a particle at rest in a relativistic theory (and in units where c=1), we of course have E = m.
This article is suspect as it mentions a "stationary electron". Such an electron would have precisely known momentum, and so exist throughout all of spacetime. This is a common starting point for solving the (e.g. Dirac) equations, but it's not physical.
mfworks|1 year ago
link: https://www.youtube.com/watch?v=G0Q4UAiKacw
programd|1 year ago
https://profmattstrassler.com/articles-and-posts/particle-ph...
tsimionescu|1 year ago
https://youtube.com/watch?v=JqNg819PiZY
throw0101d|1 year ago
Any particular reason/mechanism why the Higgs field suddenly (gradually?) switched on?
pdonis|1 year ago
"Switched on" is not really a good description. According to my understanding of our best current model, the Higgs field was not in its vacuum state in the very early universe--there were lots of Higgs particles around--so it was not "switched off" any more than any of the other Standard Model fields were. But in the very early universe, the electroweak interaction worked differently than it does now. As the universe cooled, there was a phase transition that changed how the electroweak interaction worked, and after that phase transition, the Higgs field acquired what is called a nonzero "vacuum expectation value", meaning that even though there were no longer any Higgs particles around-- the Higgs field was in its vacuum state--that vacuum state now corresponded to a nonzero value of the Higgs field, meaning that the field can interact with other fields, and that interaction is what we observe as mass for those other fields.
svachalek|1 year ago
Sniffnoy|1 year ago
LegitShady|1 year ago
So while I do not know if there is some particular cause of the higgs field, no reality like ours would exist without it, and realities without it would not look like anything we recognize (although maybe scientists could simulate it).
pb1729|1 year ago
First look at this picture [0]: https://en.wikipedia.org/wiki/Higgs_mechanism#/media/File:Me...
The Higgs field is a complex number Φ (this number can vary at different points in space, we'll come back to this, so don't worry about it for now). You can imagine it as a ball bouncing around on the landscape shown in the image. The higher the altitude of the ball, the more energy it has (just like a ball in real life). Φ = 0 corresponds to the center of the image, the point right at the top of the little hill.
At a high temperature, the ball is jostling and moving around like crazy. You can imagine constantly pelting the ball with marbles from all directions, causing it to dance eratically around the landscape. (Further, the ball doesn't experience any friction. It slows down when it happens to get hit by a marble that's heading in the opposite direction to it.) In reality, there are no marbles, of course, the jostling comes from the interactions of the Higgs field with other fields, all of which are also stupendously insanely hot.
The landscape in the picture has a rotational symmetry. You can rotate it by any angle, and it will still look the same. When the temperature is very high, the ball dances across the whole landscape. It slows down as it climbs up a slope, so it does spend less time at the bits that are at a higher altitude. But if we consider a thin ring around the center that's all at about the same altitude, the ball is equally likely to be anywhere along the ring. The average value of Φ is 0.
As the temperature decreases, the ball's motion calms down, and it spends more and more of its time in the deepest valley of the landscape. It rarely has the energy to climb high up the slopes anymore. Eventually, the ball will start to live on just the narrow ring around the center where the altitude is lowest.
Now we come back to the fact that the Higgs field is a field, which means it has a value at every point in space, and these values can differ from each other. It turns out that all fields in physics "prefer" to have similar values at nearby points in space. There is an energy penalty for fields that change rapidly in space. At high temperature, this didn't matter too much. The Higgs field had lots of energy to pay this penalty, just like it had lots of energy to climb up the slopes of the landscape. So the field here and the field 1nm to the left could have wildly different values. At cold temperatures, it matters a lot. So the Higgs field has the lowest energy if it has the same value everywhere in space. Anything else comes with an energy penalty. If we pick a point in space, and try to move the field clockwise or counterclockwise around the center, the neighbouring points in space pull the field back towards the average of the surrounding values.
So at any point in space, Φ is just equal it its average value, which is not 0. It's not zero because we have to randomly pick a point somewhere along the ring of lowest altitude, which is some distance from the central 0. The universe has randomly selected a direction in this landscape to be "special".
This is the situation from when the universe was insanely hot all the way up until the present. Incidentally, if you vibrate the ball radially, towards and away from the center of the landscape, this vibration corresponds to the Higgs boson.
If we could somehow heat the universe up to a stupendously insanely high temperature again, then the special direction would disappear, and the average of Φ would be 0 again. This is kind of similar to how magnets lose their magnetization if heated past a certain critical temperature, the Curie point. [1] If we let it cool down again, it would choose a different random special direction.
[0] https://en.wikipedia.org/wiki/Higgs_mechanism [1] https://en.wikipedia.org/wiki/Curie_temperature
hinkley|1 year ago
Zondartul|1 year ago
emrah|1 year ago
Aether was a substance filling all space, while QFT fields like higgs are not physical at all (but rather give rise to physical properties)
cryptonector|1 year ago
(Well, that's only true if you assume there's no as-yet undiscovered fields and particles with FTL that we could eventually interact with -- then we would be able to get something like measurements of speeds of everyday particles and photons relative to such fields, and if they were much faster than light then those measurements would look like "absolute speed" to us. But that's sci-fi fantasy.)
Higgs is not aether for electromagnetic waves. It's only a wee bit like aether for matter if you squint real hard, but still, it's not a medium of travel for matter, so it's not an aether.
Angostura|1 year ago
A question for the more expert amongst you. Is the Higgs field unique in its interaction with other fields, or are there other similar fields which similarly change the way that other fields (and associated particles) behave?
emblaegh|1 year ago
itishappy|1 year ago
bloopernova|1 year ago
seiferteric|1 year ago
fredgrott|1 year ago
tines|1 year ago
Compare that to a water wave, where gravity is trying to restore the particles to a "flat" position in space. If you cause a wave in water, the medium will return to the space it occupied before through the restoring force, even as the wave travels through it.
Is this really how it works, so that e.g. the EM field itself can move in space, whereas e.g. the electron field cannot move in space, it's "pinned" in some sense by the Higgs field?
wyager|1 year ago
Second, this isn't pinning the field in space, it's pinning the magnitude of the field to be close to some value (probably you can call that value 0)
So if the field locally gets "too high" or "too low", there's a restoring force accelerating it back towards the "normal" value, like a spring attached to the normal value.
It's not pinning it in the sense of stopping translation through space or time
In the water wave analogy, we're using the vertical dimension to represent the magnitude of the water wave, but translating that to other contexts, we're not literally talking about a physical height, just the magnitude of the field. (Which, for all I know, maybe you can formulate that as a position in some higher-dimensional space or something)
sieste|1 year ago
Is that really so? I've never heard this analogy, so the whole premise seems a bit of a straw man...
Sniffnoy|1 year ago
pdonis|1 year ago
As the article notes, no, this is not a correct description.
pests|1 year ago
russellbeattie|1 year ago
Personally, I've wondered why theoretical physicists don't dive into Newton's laws more. Ever since I was a kid and first learned about the Voyager probes continuing to move through space forever, my question was why??
All matter is energy, and energy is vibrations in quantum fields, and that vibration never stops (you can never reach absolute zero). From the smallest gluon bouncing between quarks to galaxies to the expansion of the universe itself, matter never stops moving. Where does this infinite source of energy come from?
I understand that physics simply describes how reality works, not why, but I think it'd be valuable to know the reason fields continue to vibrate forever.
unknown|1 year ago
[deleted]
wyager|1 year ago
The normal wave equation is (ignoring constant factors like mass and propagation velocity):
d^2/dt^2 f(x,t) = d^2/dx^2 f(x,t)
<acceleration> = <pulled towards neighbors>
This says "if a point in the field is lower than its neighbors, it will be accelerated upwards. If a point in the field is higher than its neighbors, it will be accelerated downwards." This equation is the lowest-order description of most wave phenomena like sound waves, water surface waves, EM waves, etc. and it's usually pretty accurate.
If you look for solutions to this differential equation, you can get
f(x,t) = exp(i * w * (x±t))
w is the frequency of the wave
This tells you that the frequency and wavenumber of waves is determined by the same parameter (w), so they are proportional to each other
Now, what if we add a restoring force to this equation? This is a force that pulls the value of the field towards zero.
d^2/dt^2 f(x,t) = d^2/dx^2 f(x,t) - M^2 f(x,t)
M is just a parameter that tells you the strength of the restoring force. The force increases as the field gets farther from zero, like a spring.
Now, solutions to the equation look instead like
f(x,t) = exp(i*k*x ± i*w*t)
Where w^2 = k^2 + M^2
(or something like that, I need to re-derive this on paper, just going off memory, but I think if you plug it in it should work)
Notice that now, if you have a spacial frequency k, your temporal frequency is actually higher. In fact, if your spacial frequency k is 0 (corresponding to a stationary wave), your temporal frequency is still M!
This is what mass is. Having a non-zero frequency even if the wave is the same everywhere in space (which corresponds to no movement)
A field with no restoring force is e.g. the EM field, so photons are massless. The rate at which they oscillate in time is the same rate at which they oscillate in space. A massive particle has a restoring force, so its temporal frequency is higher than its spacial frequency.
In physics, this equation is often reordered like this:
d^2/dt^2 f(x,t) - d^2/dx^2 f(x,t) = - M^2 f(x,t)
(d^2/dt^2 - d^2/dx^2) f(x,t) = - M^2 f(x,t)
(d^2/dt^2 - d^2/dx^2) f(x,t) + M^2 f(x,t) = 0
◻ f(x,t) + M^2 f(x,t) = 0
(the d'alembert operator)
(◻ + M^2) f(x,t) = 0
Again, this is ignoring constant factors like c, h, etc.
The above equation is nice because it's relativistically invariant. The d'alembert operator is the contraction of the 4-momentup operator with itself, p^u p_u. This is a concept worth studying - tells you a lot about what mass, energy, velocity, and momentum actually are in a general sense
tines|1 year ago
Wouldn't it be the opposite, that they do not oscillate in time at all so that they oscillate in space as rapidly as possible (since, as we know, time doesn't pass for photons)? And stationary particles don't oscillate in space, so they oscillate in time as rapidly as possible. Or are you using "oscillate" in a different sense here?
cryptonector|1 year ago
oytuntez|1 year ago
throw0101d|1 year ago
What are these fields made of? Are all fields made of the same thing(s), or is each field made differently?
jmcclell|1 year ago
Using wind, as an example, we can measure the wind speed/direction at various points in a given space. We don't need to know what wind is to feel its effects. Instead, we might view it as a force wave that propagates through space and interacts with everyday objects. The measurements of this force that we take at various points in space across a given area form what we might call the Wind Field. We don't need to know the nature of the medium these wind waves propagate through in order to study wind and how it interacts with other objects. This is the field perspective.
Of course, we know that wind is really an effect of air molecules moving through space. That is, the medium for wind is the atmosphere. This gives us deeper insight into what wind is and how it works. This is the medium perspective.
According to the book, we don't know what the media for the elementary particles are or if there even are any. Our intuition based on waves that we see in everyday life tell us that there must be some medium through which the wave can propagate, but thus far we have found no such medium for waves such as light.
We just know there are measurable properties that we can measure across points in space and we have created mathematical objects (fields) to represent this. From there, we can construct theories and make predictions based on these models.
akomtu|1 year ago
cosignal|1 year ago
layer8|1 year ago
cryptonector|1 year ago
oezi|1 year ago
unknown|1 year ago
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immibis|1 year ago
prof-dr-ir|1 year ago
For those who know quantum mechanics I would add that the oscillations mentioned in the article are just the familiar exp( i E t ) of any wave function that is an eigenfunction of the Hamiltonian. For a particle at rest in a relativistic theory (and in units where c=1), we of course have E = m.
idontwantthis|1 year ago
I remember reading that since I first heard about the “God Particle” in the Science Times maybe 20 years ago.
Have journalists been using that deeply flawed analogy since Higg’s hypothesis was first published?
OgsyedIE|1 year ago
TibbityFlanders|1 year ago
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simpaticoder|1 year ago