DO NEUTRONS, OR NEUTRON STARS, ACTUALLY EXIST?

I'd like to ask this strange question because I can find no reference to anyone actually seeing a neutron. We can identify they exist from spectral scattering patterns, but does this mean the neutrons actually exist? We assume they exist from our atomic and subatomic modelling, useful in chemistry to balance out the electron charge against that of the proton, but they do not seem to actually exist as seperate entities that can be seen directly. We also assume that stars with immense gravity are 'neutron' stars, but what does this actually mean? Are we giving this great gravity generating star a neutron composition, though the neutron has not been found to exist outside of spectral observations? For example, a neutron accelerator is only now being built, which should be operational by 2006, at SNS in Oak Ridge, TN, so it is at least theoretically possible to identify a neutron particle seperate from the nucleus. Will this accelerator finally identify a neutron? Or could a neutron be a 'filler' for our atomic modelling, though it may not actually exist? I've searched for where a neutron was 'seen', but have come up empty.

So my question, strange that it is since it doubts the validity of atomic science of more than a century, is that perhaps we had 'assumed' a neutron exist, but never actually seen one, and from this assumption 'imagined' neutron stars based on this assumption. Here's a paper by Harold Aspden, 1994, on Cold Fusion that may be interesting on this matter: POWER FROM WATER: COLD FUSION: PART I
So could we be wrong about what is a neutron star, or even perhaps whatis a neutron?

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Caveat Lector. Experimentum summus judex...

There is a lot of research out there on both neutrons and neutron stars, namely pulsars. They are "seen" by their rotations and large magnetic fields due to their incredibly fast angular velocity. Neutrons themselves have most certainly been used, specifically for atomic chain reactions. So if they don't exist, those reactions shouldn't work. But they do, and so someone got something right.

If neutrons didn't exist, nuclear reactors and weapons wouldn't work, and there would be no such thing as different isotopes of an element. They're as real as electrons.

There's no better explanation for pulsars than that they are rotating neutron stars.

I do not see a neutron star as a collection neutrons in "free state".

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papageno


"Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes)

"It's all about context!" - Vince Noir (The Mighty Boosh)

"I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama)

"...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation)

Agreed, there is ample evidence for neutrons, though as Papageno says, they may not be in 'free state' in a neutron star.

My specific interest in this is whether neutrons can be directly detected in some form other than 'scattering patterns', per the Oak Ridge link above:

"The SNS will produce 1.4 million watts of short proton pulses that strike the target to produce pulses of neutrons every 17 milliseconds."

Neutrons may be particles as real as electrons and protons, but why can't we see them? I realize many forces of physics are invisible, such as Gamma rays for example, or gravity, but particles should have some physical properties, I would think, that go beyond a short half-life of a few minutes. Neutrons are real in the sense we use them in our chemistry models, or how in the elements chart they are necessary for balancing out the mass with electron charge. What intriques me is that because they are invisible, other than in scattering patterns, we are assuming we understand their existence, and then inpute them into the composition of neutron stars.

A competing idea is perhaps so-called neutron stars have nothing to do with neutrons... but are just very dense gravity conditions instead. But for this to be true, it would force us to invoke a gravity-variability, which is not assumed in today's physics, where gravity is a universal constant.

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Caveat Lector. Experimentum summus judex...

Here is the Particle Data group listing for the properties of the neutron. At 17 pages I'd say that's a lot of knowledge about a particle your "source" claims doesn't exist. We most certainly have seen "bare" neutrons. When U-235 fissions it releases two neutrons in the process. If these then hit another nucleus, that will then fission. If you get enough capture, then a chain reaction occurs as in a bomb or a reactor. You can also use a reactor to create a beam of neutrons. Many such research reactors are in use around the world.

Bare neutrons decay via the beta decay channel n - > p + e- + neutrino with a mean life of about 885 seconds. When bound in nuclei, however, neutrons are more stable. Occasionally, they will undergo beta decay as in the case of Cobalt-60, the classic beta source that has a half-life of 5.3 years. The stability of bound neutrons is is a well understood process, although I need to go back to my old nuclear physics text to get a pithy quote on that.

As to your source, he's waving his hands. For one thing, his "proposal" that the deuteron is two anti-protons plus three positrons is ludicrous. Even leaving aside the issues of matter-anti-matter annihilation, the mass is wrong. Can he do the stability calculations that show that this combination is stable. How about for a nuclues like Cobalt-60. Can he account for the electrons it produces? I think not. I leave the last word to Wolfgang.

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"I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind." - William Thompson, 1st Baron Lord Kelvin

"If it was so, it might be, and if it were so, it would be, but as it isn't, it ain't. That's logic!" - Tweedledee

This isn't right. This isn't even wrong. - Wolfgang Pauli

The spin would be wrong, too. A proton and a neutron are two spin 1/2 particles, so if you have two of them, they can either be aligned, giving a net spin of +1 or -1, or anti-aligned giving a net spin 0. Two anti-protons and three positrons are five spin 1/2 particles, so the composite particle would have a spin of 5/2, 3/2, 1/2, -1/2, -3/2, or -5/2 (you can work that out: just assume each particle can be either "up" or "down", and add up the spins to see what combinations are possible). Why go with anti-particles, though? You could also get two units of mass and one of charge from two protons and one electron. Of course, that would be three spin 1/2 particles, which would have a net spin of 3/2, 1/2, -1/2, or -3/2. We know from scattering experiments that neither of these latter two compositions can be correct for the the deuteron, but if it's a single proton and neutron, that fits nicely with the data.

Can you quantify and explain this? Just what is a very dense gravity condition? Are you talking about a large gravity or a dense object's gravity?

Current theory has a neutron star is formed because gravity overcomes electron degeneracy pressure, but can't overcome Neutron degeneracy. These objects contain the mass of 1.4-~3 suns. Less mass, you have a white dwarf, more than about 3 (some say 8 solar masses) you have a black hole. These pressure's are a result of the Pauli exclusion principle.

Whose current competing idea? Could you explain how that new process works and why exactly the current process (involving GR and QM) is wrong?

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Some try to tell me, thoughts they cannot defend,... - Moody Blues.

Neptune- The original Dark Matter.

The author feels that this technique of deliberately lying will actually make it easier for you to learn the ideas. - Donald Knuth

A new theory of gravity does not exist yet, at least not in any recognizable form outside of woo-woo electrogravity possibles. Variable gravity might be a possibility, however, if astrophysical observations are considered: i.e., dark matter influenced galaxy spin, neutron star spin of hundreds of revolutions per second, galactic blackhole mystery, etc. so there could be room for some new theory in the future.

If I were to imagine a theory, it would go something like this:

The universe is a dual force function, one passive, of gravity, and the other active, of electromagnetic energy. Gravity in its pure form is of blackhole proportions, when modified by electromagnetic energy it becomes a very weak force, so what we experience on Earth, the G constant (ie, g = GMm/r^2), is a very dilluted force of the original. To find gravity greater than here, we would need to go outside the star system, or galaxy system, where the modfying effect of energy is much weakened by distance. So the interaction between this passive force and active force would give us variable gravity readings in deep space. In effect, if a star was too weak in its electromagnetic output to modify raw gravity, it would act as if there was a very great gravity there.

However, this is an imaginary theory only, so meaningless in and of itself unless there was evidence that gravity has a different value for matter away from a hot star. As of yet, this has not been detected, so not to be considered seriously.

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Caveat Lector. Experimentum summus judex...

Well, I don't think we've "seen" protons and electrons either, yet we know that they exist. If you should be able to see neutrons, you should at least be able to see them too.

So maybe protons and electrons don't exist. Maybe everything we know about atomic physics is all wrong.

It's all about seeing the effects of these things. Beta decay, chain reactions, and virtually all of particle physics have demonstrated the existence of neutrons and other particles. Using basic principles of physics their existence can be inferrerd from experiments. I see no reason to question their physical existence, though the reason for their existence might be a lot more difficult to answer.

I am sure they exist, and possibly a very powerful electron/gamma ray microscope will reveal them, but I am not certain we totally understand the neutron... If we are getting the neutron wrong somehow, can we be sure of so-called neutron stars? This is what puzzles me.

Here is a link given by a friend which may cast some light on it:
Neutron & Proton

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Caveat Lector. Experimentum summus judex...

Are you claiming we are getting the neutron wrong? If not, do you have any reason why you would think we are getting it wrong? Did you look at the link Eta C provided? The link you provided just shows why and how the neutron was detected. How does that apply to your thinking we may not understand the neutron?

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Some try to tell me, thoughts they cannot defend,... - Moody Blues.

Neptune- The original Dark Matter.

The author feels that this technique of deliberately lying will actually make it easier for you to learn the ideas. - Donald Knuth

Of course neutrons exist. And we're not getting them wrong. Just because they have a half-life of around 15 minutes doesn't mean they don't exist. We can detect them through their decay products from collision products as well as their free state decay. In fact I worked at an ion accelerator lab where they had three different neutron detector types. Most of the science in that place based their research around collision byproducts of neutrons and various isotopes.

I am sure they exist, and possibly a very powerful electron/gamma ray microscope will reveal them, but I am not certain we totally understand the neutron...

So you think an electron microscope can reveal an electron. Please feel free to do some research on electron microscopes and discover the flaw in this logic gem. But that aside...we would be able to see electrons and protons....but not neutron? What does not having charge do with not being detectable?

Here are some links that will help you figure things out a bit better:

http://particleadventure.org/particl...tstandard.html

http://particleadventure.org/particl...icle_chart.jpg

And here's are two neutron detectors from where I worked:

http://www.nscl.msu.edu/tech/devices/mona/index.html

http://www.nscl.msu.edu/tech/devices...lls/index.html

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"The bread's hollowed out --- the veggies go on forever --- and --- oh my God! --- it's full of meat!" - Maksutov

Ill throw in my 10p and make a coment which i dont think anyone actually mentioned.

"I realize many forces of physics are invisible, such as Gamma rays for example, or gravity, but particles should have some physical properties"

Im not sure i like the use of the word Invisible being as you can 'see' Gamma rays with special detectors/camera equipment. so no1 Photons (including gamma rays) are somewhat visible.
Secondly seeing a particle usually involves a particles charge, the reason we can so freely see protons and electrons say for example is just because they are charged.
so what you are really sujesting is that...
any and all particles that are neutral in charge do not exist???? because thats how i read your post Lunatik and thats a big can of worms you open.

Yes Eros, it was this 'can of worms' that made me ask the question about whether or not our understanding of neutrons is real, hence if we really can call those very great gravity stars 'neutron stars'. I realize we can see Gamma rays, and x-rays, and that an electron microscope cannot possibly be used to see electrons, though a Gamma ray microscope could in theory see particles, etc. I also realize we cannot 'see' gravity except through the effect of its accelerating action at a distance, so it is real though invisible. But the neutron is a special case, I suspect, with which physics became too easy without digging further.

I copied EtaC's 17 page reference for my research files, so appreciate it, and I appreciate the other links provided for reference, Omicron's NSCL, etc. so have more to review for what I am looking for. I do not wish to debunk current theory on the neutron, which would be lunacy since there is so much evidence for its existence, but I am interested in thinking of it differently. Rather than accepting that what the big machines measuring cosmic rays show us in their particle trails, where we are actually looking at 'shadows' of existence, I would rather step back one and think of positive and negative charge as conditions of a dual force universe composed of gravity and electromagnetic energy. So this is a paradigm shift question, does the neutron actually exist (?), to backtrack us out of seeing the atom ONLY as positive and negative charges, with a 'neutral' charge thrown in, but perhaps as something else we had not yet considered. I know this is chancy,going up against a mountain of accepted theory, but science is questions.

Like in Eros' "any and all particles that are neutral in charge do not exist????", I would suggest that these neutral particles can exist, obviously had been photographed and measured, have been shown to collide and cause fission, the evidence is mountains of data going back to the first particle accelerators... but! Are they real? Or are they a shadow existence of how electromagnetic energy and gravity interact? Or are they (blank blank blank)... what you might imagine?

If all neutron existence is based on circumstantial evidence from machines that measure their trails, particle accelerators that collide them with other particles, and fissionable atoms to blow up with megatons of power, we of necessity are forced into interpreting this data, since we cannot see it directly with our senses. I realize this is more a question of philosophy than science, but science is a philosophical state of understanding too, where what is believed is tested against what is real. So my question, really asking about neutron stars, is whether or not neutrons are real in the sense that we understand them, or are they something else that we still do not understand? One possible is that they represent another state of interaction between electromagnetic energy and gravity.... which is not yet theorized in current physics...

Am I making any sense to anyone, or am I really talking to myself?... Not a problem, it would not be the first time.

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Caveat Lector. Experimentum summus judex...

Lunatik,

I do not understand why you do not accept the neutron as real particle, given the evidence available.

You accept the proton as real particle, but not the neutron.
Yet the difference between those two particles are not that big (to the point that it is possible to treat them as the same particle in two different states).

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papageno


"Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes)

"It's all about context!" - Vince Noir (The Mighty Boosh)

"I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama)

"...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation)

I realize we can see Gamma rays, and x-rays

No we can't. We see them through their interaction with matter in just the same way we see neutrons. Gamma rays and x-rays are light...plain and simple. They are on the far end of the electromagnetic spectrum and have a very short wavelength (in quantum mechainical terms they are high energy photons). We can't SEE them directly. We see their interaction with matter and convert that into a signal. We do the same with neutrons.

I would suggest that these neutral particles can exist, obviously had been photographed and measured, have been shown to collide and cause fission, the evidence is mountains of data going back to the first particle accelerators... but! Are they real? Or are they a shadow existence of how electromagnetic energy and gravity interact? Or are they (blank blank blank)... what you might imagine?

Um....yes we DO have mountains of evidence. And we the have the math to back us up. If there were no neutrons then there would be no fission reactors or fusion reactions or atomic bombs....because our math and data wouldn't work to build them. But they do work because we have a good understanding of neutrons...as well as quarks (which are what neutrons and protrons are composed of).

So instead of questioning these claims with failed logic, maybe you should learn a thing or two about particle physics. Photons have no mass or charge so do they not exist? That would mean gamma rays and x-rays would'n exist either, nor visible light for that matter; you're applying the same logic in this case.

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"The bread's hollowed out --- the veggies go on forever --- and --- oh my God! --- it's full of meat!" - Maksutov

Indeed. One thing to remember, Lunatik, is that as far as the strong nuclear force is concerned, neutrons and protons are identical. That's what allows an atomic nucleus to hold together against the electromagnetic repulsion of all those protons. May I suggest you look into some real scientific sites as opposed to oddball ones. A good start is the APS's Physics Central site. It's a site for non-scientists hosted by the professional society of America's physicists.

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"I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind." - William Thompson, 1st Baron Lord Kelvin

"If it was so, it might be, and if it were so, it would be, but as it isn't, it ain't. That's logic!" - Tweedledee

This isn't right. This isn't even wrong. - Wolfgang Pauli

Thanks for reference Eta C, will examine it too, for my being a non-scientist it should help.

Papageno, it's not that I don't accept a neutron as a 'real particle', but that I have doubts as to how we simply used energy conservation calculations to derive its chargeless mass, per Chadwick, and concluded since it has the same mass as a proton, it is something like it but neutral. I realize we have lots of reasons to think we are right, but that does not mean we are right, and may have missed something by jumping to the conclusion that its mass being equal to a proton's means it is merely an electron-proton cancelation into neutrality. The real question may not be whether or not a neutron actually exists, since it is obvious it does, but whether or not we truly understand what is mass. Of course that is a complex question with many complex answers, right up to E = mc^2, but a gravitational definition of mass may yield a better understanding of so-called neutron stars, and hence redefine what really is a neutron.

Omicron, I understand Gamma/X-rays are merely higher frequency light, high energy photons, very short wavelength too small to see with the naked eye, hence we need instruments to convert their signal into something we can image. Ditto for the neutron. Atomic bombs prove we know something of how the neutron works. My real interest, however, is neutron stars, since they are supposed to be where positive/negative charge are 'neutralized' into a very massive gravitational star. If we were to call neutron stars 'gravity stars' instead, we might have a semantic reason to view them differently than we view them now. But we don't call them gravity stars, do we?

If it is a question of mass, we're back to asking exactly what is mass? We know energy conservation law requires that the mass of a neutron being identical to that of a proton, and we are exploring Zero point energy assuming mass as being something connected with gravity, so inertial mass is a function of its gravity. Now, if neutron stars have very great gravity, which they do, what is their inertial mass? Very great, of course. But if their inertial mass is very great, then can we say that a neutron, which has the same mass as a proton, have a greater inertial mass? No. The standard answer is that neutron stars are very compact, hence tremendous mass and gravity. It is at this point that my question on the actuality of a neutron, or neutron star, resurfaces: do we actually know what is a neutron, or what is mass?

I do not think asking questions like this is indicative of failed logic, though some of the responses lead me to think that the logic for what we think we already know is concluded as indisputable, so that one should never ask these questions. I disagree. Science is questions. :-? 8)

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Caveat Lector. Experimentum summus judex...

The mass of a neutron does not equal exactly the mass of a proton (charge does make a difference) .

In the current theory, both neutron and proton are made of quarks (which have electric charge).
So the problem of the mass of the neutron becomes the problem of the mass of the quarks.
If we understand the mass of the proton, we understand the mass of the neutron.

The problem of the origin of mass does exist and has not been resolved, yet.
But it does not lie at the level of the neutron: it goes deeper.

Atomic bombs are just one piece of the evidence.
We have a lot more.

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papageno


"Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes)

"It's all about context!" - Vince Noir (The Mighty Boosh)

"I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama)

"...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation)

Lunatik,

You need to read up on quarks:

http://hyperphysics.phy-astr.gsu.edu...les/quark.html

and neutron degeneracy:

http://hyperphysics.phy-astr.gsu.edu...ro/pulsar.html

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"The bread's hollowed out --- the veggies go on forever --- and --- oh my God! --- it's full of meat!" - Maksutov