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Posted

One of our number having been banned for sockpuppetry I was wondering about the  interpretation(?) introduced into his recent kinetic energy/classical vs quantum spin thread by Mordred  .

He seems to have come down very firmly on the interpretation of reality (that 7 letter word ;) ) being made up of fields  and solidity being the great illusion (if I paraphrase correctly)

Can we put more meat on the bone perhaps? (esp the idea that  fields trump particles and knock them out of the park)

Are there thought to be whole families of fields? Can  they all interact with each   other ?

 

Is  the gravitational field a very special kind of field (a field of fields perhaps) ?

 

There seem to be lots of questions queuing up in my mind  so I had better stop there as I  have probably introduced misunderstandings  based on "little knowledge" already.

Posted (edited)

Not quite, Physics is never about defining reality. We leave that task to philosophers lol. One thing I always stress is a field is an abstract device. A field is precisely a treatment under geometric basis, where every coordinate is assigned a function. That function will provide either a scalar or vector/spinor quantity.  Now that is clarified onto particle themselves. Its no mystery that everyday objects are comprised of particles. The coupling strength of the EM force provides us our sense of solid. Everyone pretty much understands this. However most people run into difficulty letting this "solid thinking" go when it comes to the quantum realm.  They look for that solidity in particles.

The wave particle duality teaches us that a particle has both wavelike and pointlike characteristics. However they tend to confuse two key aspects.

The wavelike characteristic in this instance is not the probability waves. The probability waves simply provide the probability of locating said particle in point of detail the probability wave can have any number of particles. The particle excitation defined by the Compton wavelength for force particles and the Debroglie wavelength for the matter particles.  For the matter particles when the pointlike characteristic becomes meaningful, the region of said particle is DeBroglie wavelength.  Now each of these two waveforms have distinctive cutoff points except the HUP makes it tricky to pin down as it will always be inherently fuzzy due to the HUP. These two wave are akin to physical waves not  probability

 So lets ask some questions.

1) the electron is a fundamental particle, it is not made of smaller particles. Yet has no internal structure. So lets think about that for a minute. How can a solid electron not be made up of smaller particles if it is solid ?

2) How does a solid particle pop in and out of existence, from where and how ? the novice tends to think quantum tunneling but that is wrong.

3) if you supercool an electron to a Bose Einstein state, why does it no longer appear spherical but becomes squiggly lines ?

4) How can a neutrino pass through a 1000 lightyears of lead without being deflected. It should hit another solid particle at some point. Simple statistics tells is that.

Now lets borrow a passage from a condensate state article.

"When this happens, the sample undergoes a phase transition: a Bose Einstein condensate forms. Because the particles in the BEC are all in a single quantum state (i.e. the ground state), they can be described by a single wavefunction. The constituent particles in a BEC can thus be likened to a ‘superatom,’ a system in which thousands or even millions of atoms behave like a single particle. The phase transition can be understood in terms of the particles’ thermal de Broglie wavelength."

 Now this indicates that particles can and do alter their waveforms and become indistinguishable from one another. This condition is thermal equilibrium.

How would that be possible if different particle types are solid?

When you start examining the body of evidence it becomes more and more clear that particles are precisely that "Excitations" and not solid.

With excitations particle production answers all the above questions. The pointlike characteristic is indeed the DeBroglie wavelength. This is what any QM related field teaches us and experiments reflect. Nor are they made of Strings, that is not what String theory teaches.

Here is the random grab BEC paper I borrowed that quote from.

https://www.google.ca/url?sa=t&source=web&rct=j&url=http://massey.dur.ac.uk/resources/mlharris/Chapter2.pdf&ved=0ahUKEwiVt4vUw_HXAhUQyWMKHQ91DtMQFggkMAE&usg=AOvVaw1DHUh-BTAMS7yr-2lNfTFf

A little sidenote you will be amazed how much easier physics becomes to understand when you can discard looking for "solid" or a fundamental cause where everything starts. Though by understanding potential differences between regions (anistropy is an immense help). As well as thinking of charge (attraction/repulsion) of any type as vectors. 

Edited by Mordred
Posted
13 minutes ago, Mordred said:

However they tend to confuse two key aspects.

The wavelike characteristic in this instance is not the probability waves. The probability waves simply provide the probability of locating said particle in point of detail the probability wave can have any number of particles. The particle excitation defined by the Compton wavelength for force particles and the Debroglie wavelength for the matter particles.  For the matter particles when the pointlike characteristic becomes meaningful, the region of said particle is DeBroglie wavelength.  Now each of these two waveforms have distinctive cutoff points except the HUP makes it tricky to pin down as it will always be inherently fuzzy due to the HUP.

 

13 minutes ago, Mordred said:

With excitations particle production answers all the above questions. The pointlike characteristic is indeed the DeBroglie wavelength. This is what any QM related field teaches us and experiments reflect. Nor are they made of Strings, that is not what String theory teaches.

 

Some very good kitchen table descriptions here to take note of.

I particularly liked the two above

+1

Posted

Guys, have to say from an interested (non expert) bystander point of view - fascinating discussion.

Thanks

Posted

Thanks Mordred, really loved your explanation. 

+1

I would like some more context on this, though:

On 12/5/2017 at 7:52 AM, Mordred said:

3) if you supercool an electron to a Bose Einstein state, why does it no longer appear spherical but becomes squiggly lines ?

What becomes squiggly lines?

Posted (edited)

watch what happens to the images of the atom in transition to the Bose condensate state from this video

Notice how the atoms appear to deform as it undergoes the phase transitions to the Bose condensate state? a lot of pop media articles mislead this loss of information phase transition under the descriptive squiggly lines. Keep in mind this is a graphic animation of the process including the images of the atoms etc in the first place. Not actual images of the atom in the first place lol. The mere act of trying to measure a condensate state heats up that state thus causing further phase transitions. In condensate state one cannot identify individual particles as per the article I attached above.

Edited by Mordred
Posted (edited)

Your welcome and excellent valid question. The details is the first section of the article I linked where all the constituents of the sodium atoms become describable under a single wavefunction via equation 2.2 De-Broglie wavelength. LOL if you look at that article the visual aid also has the squiggly lines in figure 2.1. That's what that image is trying to describe

Edited by Mordred
Posted
On 12/5/2017 at 12:52 AM, Mordred said:

the electron is a fundamental particle, it is not made of smaller particles. Yet has no internal structure. So lets think about that for a minute. How can a solid electron not be made up of smaller particles if it is solid ?

Mordred, if an electron (assuming it is a point particle) doesn't have an internal structure where does it get it's mass from?

Posted
1 hour ago, Silvestru said:

Mordred, if an electron (assuming it is a point particle) doesn't have an internal structure where does it get it's mass from?

Another excellent question and one deserving an equivalent answer.

What is mass? well the correct way to thinking of mass is resistance to inertia change. Which is the definition of mass under physics. Under particle physics treatments the mass term arises from the coupling constant [math]\alpha=\frac{e^2}{4\pi \epsilon_0 \hbar c}[/math]

https://en.wikipedia.org/wiki/Coupling_constant

 

Posted
45 minutes ago, Mordred said:

Another excellent question and one deserving an equivalent answer.

What is mass? well the correct way to thinking of mass is resistance to inertia change. Which is the definition of mass under physics. Under particle physics treatments the mass term arises from the coupling constant α=e24πϵ0c

https://en.wikipedia.org/wiki/Coupling_constant

 

Thank you very much Mordred. I also found a paper related to this, maybe you can check it out as I am unsure about some conclusions that it draws. (I'm mathematically limited)

https://arxiv.org/PS_cache/arxiv/pdf/0704/0704.2232v2.pdf

Quote

“Does the inertia of a body depend upon its energy content?” and his powerful conclusion, “The mass of a body is a measure of its energy content; if the energy changes by L, the mass changes in the same sense by [L/c2 , where c is the speed of light].” Mass is rest-energy §. Among the virtues of identifying mass as m = E0/c2 , where E0 designates the body’s rest energy, is that mass, so understood, is a Lorentz-invariant quantity, given in any frame as m = (1/c2 ) p E2 − p 2c 2 . But not only is Einstein’s a precise definition of mass, it invites us to consider the origins of mass by coming to terms with a body’s rest energy.

 

Posted (edited)

Yes that is a very good paper and quite detailed on the process of mass. In greater detail the process in the paper can also help understand particle generations of the SM model via the symmetry breaking process and the Higg's field interactions. Though keep in mind the paper is rather out of date on the Higg's research itself since the paper was published we have identified the Higg's boson and the mass term of the Higg's so many of the numbers the paper provides will change as a result.

Edited by Mordred
Posted

Something to remember when discussing mass and other parameters.

It is called renormalisation.

http://www.volkerschatz.com/science/renorm.html

In regards to mass it involves replacing the mass one would measure for a free isolated particle by what is called the 'effective mass' in formulae such as QM or Newton's second law.

The effective mass is based on the free mass but modified by the environment.
The environment inclues the self interaction by the particle particularly in quantum field theory.

The QFT version is difficult.

 

The original proposal by Green in 1830 in regards to replacing mo in Newton's second law by me = (mo + 0.5M) in hydrodynamics.

M is the mass of the water displaced by the particle and Newton's second law works properly using me.

Posted (edited)
On 12/7/2017 at 4:31 AM, Mordred said:

watch what happens to the images of the atom in transition to the Bose condensate state from this video

Notice how the atoms appear to deform as it undergoes the phase transitions to the Bose condensate state? a lot of pop media articles mislead this loss of information phase transition under the descriptive squiggly lines. Keep in mind this is a graphic animation of the process including the images of the atoms etc in the first place. Not actual images of the atom in the first place lol. The mere act of trying to measure a condensate state heats up that state thus causing further phase transitions. In condensate state one cannot identify individual particles as per the article I attached above.

What would happen if one attempted to make  a similar simulation at comparable degrees of definition  with the two slit experiment.?

 

When a photon lands on the screen behind the two slits  the  region where it lands (and leaves a distinctive bounded record when viewed macroscopically) is presumably and usually  a seething  hive of activity  as atoms on the physical screen bounce around ....

Is it possible ,in theory if not in practice with a surface that exhibits complete  rigidity ? If for example the screen was cooled to absolute zero.

Can the arrival of a particle on such a screen be shown in a similar way to that in which the BE condensate is shown above.?

 

As a general question , when  decoherence occurs is it accompanied by a transfer of energy? (Can this transfer be shown graphically in a simulation?)    

 

One last general question :is it possible to view  the   general relationship between wave and particle manifestations/presentations  as an "emergence"  or a "phase  transition" ?

Edited by geordief

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