B The Term "no mass" is poorly defined

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Come across the mentioning that some particles have "no mass". Is this stated by physicists because there simply isn't evidence to prove that they have mass. It doesn't seem logical to make a fact based on absence of information to the contrary.

All particles must have some form of mass in order to have validity in interaction with other particles and establish a boundary of interaction and function. If it had no mass, then it would have no container for its influence and function.
 

Orodruin

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Come across the mentioning
This is not a valid reference. Please provide a valid source.

some particles have "no mass". Is this stated by physicists because there simply isn't evidence to prove that they have mass. It doesn't seem logical to make a fact based on absence of information to the contrary.
This depends on context, which you have not provided. The photon is treated as massless because there is only a (very stringent) upper bound on its mass. Therefore, in the standard model of particle physics, it is treated as being massless. Being a gauge theory, it is also required from the theory itself that the photon is massless. So far, all experimental evidence is consistent with this prediction.

All particles must have some form of mass in order to have validity in interaction with other particles and establish a boundary of interaction and function. If it had no mass, then it would have no container for its influence and function.
Sorry, but this is just word sallad and has nothing to do with actual physics. Mass is a property of a system, nothing else. It has nothing whatsoever to do with being any form of "container".
 
An example I am referring to is this Link here. Perhaps not the best source as it comes straight from the internet, in which case I would appreciate any direction towards reliable sources which can provide core understanding and context to the behaviour of particles.

They state that the neutrino might have "no mass". How does this compute in the grand scheme of things? If it has no mass, then where does the influence of a single neutrino "meet its border" as they participate in the weak force.

Word *salad is the best way to express ones opinion IMO.
 

Orodruin

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They state that the neutrino might have "no mass". How does this compute in the grand scheme of things? If it has no mass, then where does the influence of a single neutrino "meet its border" as they participate in the weak force.

Word *salad is the best way to express ones opinion IMO.
It is, however, an awful way of doing physics. Your description has absolutely nothing to do with how the weak interaction is modelled. The description of the electroweak and strong forces in the standard model of particle physics is based on a precise mathematical model. According to this model, there is absolutely nothing wrong with having interactions with massless particles. As long as appropriate conservation laws are satisfied (such as energy and momentum conservation), there is nothing wrong with those processes involving massless particles. The photon is a massless particle and it interacts quite readily with charged particles.

Your reference also shows no publication date, but Art McDonald won (half) the Nobel prize 2015 for his contributions to the SNO experiment showing that neutrinos do have mass. (The other half of the prize going to T Kajita for his role in the Super-K experiment.)
 
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Is this stated by physicists because there simply isn't evidence to prove that they have mass. It doesn't seem logical to make a fact based on absence of information to the contrary.
On the contrary we have very good information on, for example, the 0 mass of a photon. That has been measured with a variety of exquisitely precise measurements, all of which have been 0 to within the experimental error.

Of course no measurement of any quantity has infinite precision, so there is a small range of values around 0 that would also be consistent with the data. But that small uncertainty doesn’t imply an absence of information. The information that we do have is quite strong and provides strong support for 0 mass.
All particles must have some form of mass in order to have validity in interaction with other particles and establish a boundary of interaction and function. If it had no mass, then it would have no container for its influence and function.
None of this is correct.
 

Vanadium 50

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Your reference also shows no publication date
It's from 1999. The OP is using a 20-year old article that doesn't even say what he says it says (it says the mass is small and might be zero) to defend his opinion that scientists are all doing it wrong.
 
It is, however, an awful way of doing physics. Your description has absolutely nothing to do with how the weak interaction is modelled. The description of the electroweak and strong forces in the standard model of particle physics is based on a precise mathematical model. According to this model, there is absolutely nothing wrong with having interactions with massless particles. As long as appropriate conservation laws are satisfied (such as energy and momentum conservation), there is nothing wrong with those processes involving massless particles. The photon is a massless particle and it interacts quite readily with charged particles.

Your reference also shows no publication date, but Art McDonald won (half) the Nobel prize 2015 for his contributions to the SNO experiment showing that neutrinos do have mass. (The other half of the prize going to T Kajita for his role in the Super-K experiment.)
Could you advise me of some possible sources of reliable information that provide some more in depth explanations of quantum mechanics for beginners?
 
It's from 1999. The OP is using a 20-year old article that doesn't even say what he says it says (it says the mass is small and might be zero) to defend his opinion that scientists are all doing it wrong.
So passive forum slandering aside, could you gentlemen perhaps point me in the direction of some reliable sources of information that can give a breakdown of quantum mechanics for someone who is just starting out?

Cheers
 
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The issues you've raised in your OP belongs to quantum field theory rather than quantum mechanics, but to understand QFT you have to understand QM... And you can start with this one:
 

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Orodruin

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So passive forum slandering aside, could you gentlemen perhaps point me in the direction of some reliable sources of information that can give a breakdown of quantum mechanics for someone who is just starting out?

Cheers
Your OP started out by making a claim, not making a question. Your title suggests that you are promoting an idea that is strongly misguided, not making a question, and the rest of the OP is in the same vein. If you are just starting out, this is not a constructive way to learn.
 
The issues you've raised in your OP belongs to quantum field theory rather than quantum mechanics, but to understand QFT you have to understand QM... And you can start with this one:
Much appreciated, cheers
 
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Coming late to topic, may I caution that claiming 'no mass' is dangerously inadequate, especially if 'No Rest Mass' was intended ?

There's some very sloppy 'popular' presentations about, and a surfeit of woo, at best due misunderstanding. IMHO, any claim of 'no mass' is too-often a red flag that worse errors may lie ahead...
YMMV.
 
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Coming late to topic, may I caution that claiming 'no mass' is dangerously inadequate, especially if 'No Rest Mass' was intended ?

There's some very sloppy 'popular' presentations about, and a surfeit of woo, at best due misunderstanding. IMHO, any claim of 'no mass' is too-often a red flag that worse errors may lie ahead...
YMMV.
I disagree with this. While it doesn't hurt to clarify, the standard scientific meaning of the term "mass" is the invariant mass. The other type of mass, "relativistic mass", is rather strongly deprecated by the professional scientific community.

So "no mass" is both adequate and standard usage. While it does no harm to say "no invariant mass", but it is cumbersome and typically unnecessary.

Btw, I prefer the term "invariant mass" instead of "rest mass"
 
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