Laws clearly state matter couldn`t be destroyed

In summary, the conversation discusses the laws of conservation of energy and matter, specifically in relation to whether matter can be destroyed or created. The participants also discuss the production of neutrinos in various processes, such as electron-positron annihilation and nucleon-nucleon bremsstrahlung. It is concluded that while neutrinos can be produced in certain high-speed collisions, they cannot be produced in annihilation processes.
  • #1
fedorfan
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0
I know laws clearly state matter couldn`t be destroyed but I believe if you got a big enough explosion with enough heat then it could happen. I just want to know if it could happen and if it couldn`t, is there a way to turn matter into complete energy(no other matter produced or anything whatsoever)? I am a newb and don't know a whole lot so go easy on me please.
thanks and excuse my stupid question but please answer it
 
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  • #2
Laws also state that matter cannot be created. Why do you believe a big enough explosion will destroy matter? More specifically, what is big enough?
 
  • #3
The law you're referring to states energy cannot be created or destroyed, it can only transfer forms. And since matter is essentially energy (right?), it holds for matter.
 
  • #4
Right. The matter can be "destroyed" in the sense that it ceases to exist as matter. It becomes EM and/or some other form(s) of energy.
 
  • #5
LURCH, that's basically what I was asking. So no matter whatsoever is produced or still there or anything right?
 
  • #6
fedorfan said:
LURCH, that's basically what I was asking. So no matter whatsoever is produced or still there or anything right?

Right... take for instance the decay of the neutral pion. Its primary decay mode is into two photons (approx. 98%). See the http://pdg.lbl.gov/2006/listings/s009.pdf" listing.

This doesn't take massive amounts of energy to happen- just the amount of energy it takes to create the pion.
 
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  • #7
fedorfan said:
. . .if you got a big enough explosion with enough heat then it could happen. . . . .
Chemical explosions release the chemical energy stored in the bonds of molecules, and the energy is manifest in the gaseous products. For a given mass, the gas occupies a much greater volume than the solid or liquid phase.

In nuclear fusion or fission, the nuclear binding energy is also transformed into energy. There is a loss of mass, and the is an equivalence between the mass loss and the energy (kinetic) released.

In addition to the neutral pion decay, we have annihilation of the electron and positron, in which the two particles (matter) annihilate each other producing two photons (gamma rays), which are not matter.
 
  • #8
Alright, thanks a lot yall, that's what I wanted to know.
 
  • #9
I asked this question elsewhere and was told a neutrino was made in annihilation and was told a neutrino is matter.
 
  • #10
fedorfan said:
I asked this question elsewhere and was told a neutrino was made in annihilation and was told a neutrino is matter.
The neutrino is a very small neutral particle. Neutrinos, of which there are a few kinds, are considered to have rest mass, but no one has isolated any. Neutrinos interact so little with matter that they can pass through millions or billions of miles of matter without significant interaction. However, they are occasionally detected by virtue of certain nuclear interactions.

Here is a nice overview of neutrinos - http://hyperphysics.phy-astr.gsu.edu/Hbase/particles/neutrino.html
http://hyperphysics.phy-astr.gsu.edu/Hbase/particles/neutrino2.html

NEUTRINO DETECTION EXPERIMENTS
http://wwwlapp.in2p3.fr/neutrinos/anexp.html

Particles in general
http://hyperphysics.phy-astr.gsu.edu/Hbase/particles/parcon.html

Neutrinos arise from decay of neutrons (e.g. beta decay) and in the decay of pions and muons. See - http://hyperphysics.phy-astr.gsu.edu/Hbase/particles/lepton.html
 
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  • #11
fedorfan said:
I asked this question elsewhere and was told a neutrino was made in annihilation and was told a neutrino is matter.

Who told you this, and under what circumstances was the neutrino produced?

Zz.
 
  • #12
My friend told me this and said it was made in normal antimatter-matter annihilation. Is he correct?
 
  • #13
fedorfan said:
My friend told me this and said it was made in normal antimatter-matter annihilation. Is he correct?

Ask your friend how he/she intends to explain the non-conservation of, let's say, spin, when electron-positron collide and anhilate to produce a neutrino.

Zz.
 
  • #14
Oh, sorry yall. I misunderstood him. He says neutrino is what's left over.
 
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  • #15
fedorfan said:
Oh, sorry yall. I misunderstood him. He says neutrino is what's left over.

That still doesn't make any sense, or make it better. What does it mean as having "neutrino is what's left over"? Doesn't this mean that a neutrino is produced AFTER the collision? That still violates the conservation of spin, leftover or not.

Zz.
 
  • #16
Alright I see what youre talking about.
 
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  • #17
fedorfan said:
Yeah, I guess youre right. A neutrino is never produced.

You're going to pull your hair over this, but this isn't correct either! Notice what I asked you the first time you said this:

ZapperZ said:
Who told you this, and under what circumstances was the neutrino produced?

I specifically asked under what circumstances would such a thing produce a neutrino. This is because while a typical electron-positron anhilation would not produce one, an electron-positron high energy collision could, along with other particles. This is what you get at the old LEP collider at CERN. When you produce a lot of "crap" during the collision, then a number of things can occur that can produce neutrinos and still preserve these conservation laws.

What cannot happen is electron-positron anhilation that produces JUST a neutrino.

Zz.
 
  • #18
Alright I see what youre talking about.
 
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  • #19
I give up.

Zz.
 
  • #20
Sorry, we posted at the same time. I see what youre saying now. Youre saying that a neutrino can be produced in a high speed collision and nothing but photons is produced in normal annihilation right? If youre not, then I give up too.
 
  • #21
fedorfan, it would help in the discussion if you would ask your friend to identify the annihiliation process he believes creates neutrinos, and also from what reference the friend obtained the information.

fedorfan said:
Sorry, we posted at the same time. I see what youre saying now. Youre saying that a neutrino can be produced in a high speed collision and nothing but photons is produced in normal annihilation right? If youre not, then I give up too.
That appears to be what Zz is saying. In 'normal' electron-positron annihilation, the two combine and produce 2 gamma-rays of approximately 0.511 MeV (equivalent to the rest mass of either electron or positron).

However, apparently under some circumstances, electron-positron annihilation may produce neutrinos, but as Zz pointed out conservation laws require a neutrino-antineutrino pair.
Nucleon-nucleon bremsstrahlung has recently been recognized as an important neutrino production mechanism in supernovae. Other neutrino production processes include the charged-current reactions, which produce electron and anti-electron neutrinos, plasmon decay, and electron-positron annihilation. The latter two processes, like bremsstrahlung, produce neutrinos of all species. Bremsstrahlung has been ignored as a production mechanism in fully dynamical supernova calculations to date as it has been assumed sub-dominant in comparison with electron/positron annihilation.
ref: http://zenith.as.arizona.edu/~burrows/eos.wind.thermal/thermal.html
Thermalization and Production of Neutrinos in Dense Nuclear Matter
Todd A. Thompson

See also - Todd A. Thompson, Adam Burrows, and Jorge E. Horvath,
http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PRVCAN000062000003035802000001&idtype=cvips&gifs=yes&jsessionid=217215988820896317

Other neutrino sources are discussed in post #10, and see also -
http://hyperphysics.phy-astr.gsu.edu/Hbase/astro/procyc.html
 
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  • #22
My friend said a neutrino is what wasnt turned into energy in normal annihilation. But yall are saying he is wrong right? That in normal annihilation(not high speed) nothing but photons is produced. Or are yall saying he's right?
 
  • #23
fedorfan said:
My friend said a neutrino is what wasnt turned into energy in normal annihilation. But yall are saying he is wrong right? That in normal annihilation(not high speed) nothing but photons is produced. Or are yall saying he's right?
Annihilation of what. We've discussed annihilation involving electron-positron, but we haven't yet discussed proton-antiproton annihilation. In that case, one gets a number of possibilities depending on the total energy involved, but usually some type of hyperon pair is produced, and these decay into pions and protons.

It would appear we contradict your friend. A nice comment from a text states "Leptons, like baryons, can be created or destroyed only in particle-antiparticle pairs".

It would help us to know to what annihiliation reaction your friend is referring.
 
  • #24
fedorfan: energy is a property. This means that something has energy, in the same way that something has colour. Think of a color, like red. It can't exist on its own. Something has to be red. In the same vein energy can't exist on its own. So you can turn something that has mass into something that has energy, but you can't "turn it into energy".

And as to what the somethings really are, I'm none too sure myself.
 
  • #25
He was talking about electron-positron annihilation. So yall are saying he's wrong?
 
  • #26
As far as I know, the only "direct" way to get neutrinos out of an e+e- collision is to produce a neutrino-antineutrino pair via a virtual Z0. A virtual photon won't do it because photons couple only to charged particles.

What you can do is produce other kinds of particles (along with their antiparticles of course) which in turn decay into neutrinos. For example, with enough energy you could get a tau-antitau pair, each of which can decay into other leptons plus neutrinos, e.g. tau -> muon + antineutrino.
 
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  • #27
fedorfan said:
He was talking about electron-positron annihilation. So yall are saying he's wrong?
If your friend is saying the e- - e+ annihilation produces a single neutrino, then yes we are saying he is wrong.

As ZapperZ mentioned, annihilation produces particle-antiparticle pairs. Normal electron-positron annihilation produces two gamma rays (a photon is its own antiparticle, but photons do not annihilate each other - which is not the same as destructive interference).

Annihilation of high energy electron-positron pairs can produce some exotic particles, and if one refers to post #21, I cite a paper that discusses the production of neutrinos in electron-positron annhiliation - which is more or less normal in a supernovae, but not normal on earth. I have not read the paper which is cited, but based on jtbell's post, I have to imagine some intermediate particles which decay (with extremely short lifetimes) into neutrinos.
 
  • #28
I think the dominant process in high-energy e+e- collisions is to produce a single virtual photon or Z0 which "decays" into a particle-antiparticle pair. That pair can be anything that there's enough energy to produce: e+e-, mu+mu-, quark-antiquark (which then gets "dressed" with more quark-antiquark pairs which recombine to produce mesons and baryons), etc.

By "tuning" the collision energy to match the mass of a desired kind of particle-antiparticle pair, you get a resonance which enhances the production of that kind of pair. This is one thing that makes e+e- colliders so useful. They can be efficient "factories" for other kinds of particles.
 
  • #29
So in electron-positron annihilation no matter what a neutrino-antineutrino is produced? Is there any reaction at all where all the matter is turned to energy and there is no matter produced whatsoever? Like nothing decays into something else that is matter or does matter always show up in one form or another? Also, is there anything in the universe that is say...heat proof(cant be melted and boiled)? One other question, could you take a solid, then melt it to liquid, then boil it to make a gas, then burn the gas all up? If you could do that, would you be able to turn the stuff all into energy with no other matter showing up? I know its a lot of stupid matter questions but I am just debating with someone.
 
  • #30
So in electron-positron annihilation no matter what a neutrino-antineutrino is produced? Is there any reaction at all where all the matter is turned to energy and there is no matter produced whatsoever?
Well, normally an electron-positron annihilate into two photons (gamma-rays). This we have previously stated. IF an electron-positron annihilation produces neutrinos, it MUST do so according to several conservation laws (of which mass-energy is one) and any neutrino must be accompanied by an anti-neutrino.

Also, the neutral pion decays into photons (gamma-rays), most of the time, but could also decay into a gamma and an electron-positron pair, and very rarely into three gammas, or two electron-positron pairs.

Like nothing decays into something else that is matter or does matter always show up in one form or another?
In a decay, matter and energy are transformed!

In pair production, a high energy gamma ray (E > 1.022 MeV) interacts within the nuclear field and produces an electron-positron pair. Eventually, in matter, the positron slows down and annihilates with an electron. Then electrons in the matter migrate to achieve charge neutrality, i.e. the atoms balance the number (Z) of nuclear protons with the same number of electrons in the atom.

Also, is there anything in the universe that is say...heat proof(cant be melted and boiled)? One other question, could you take a solid, then melt it to liquid, then boil it to make a gas, then burn the gas all up? If you could do that, would you be able to turn the stuff all into energy with no other matter showing up?
In short, NO! Solid to liquid, and liquid to gas, are phase transformations. Any thermal energy goes into disrupting the attractive bonds between atoms/molecules. In a gas, the atoms/molcules are free more or less. 'Burning' as gas involves a chemical reaction - but then noble gases (He, Ne, Ar, Kr, Xe, Rn) do not burn, although Kr can form fluorides and Xe can form fluroides and oxides under special conditions. A chemical reaction simply involves rearraging atoms - not 'destroying' them. The energy released is effectively the stored chemcial potential energy, which is transformed into thermal or kintetic (molecular or atomic (not nuclear)) energy.
 
  • #31
So there is a reaction where nothing but energy is produced? Normal low energy electron-positron annihilation, right?
 
  • #32
fedorfan said:
So there is a reaction where nothing but energy is produced? Normal low energy electron-positron annihilation, right?

If the energy of the electron positron annihilation is too low to support massive particles, it produces photons. No lower limit on the amount of energy that photons can carry, just make the wave lengths longer.

There is no such thing as pure energy.
 
  • #33
Thats what I've been asking, ok, so you can't turn matter into pure energy. It always shows up on the subatomic scale or somewhere else. Thanks
 
  • #34
fedorfan said:
Thats what I've been asking, ok, so you can't turn matter into pure energy. It always shows up on the subatomic scale or somewhere else. Thanks
Well photons have no rest mass (but they do have momentum (p = E/c), so in one sense, they are pure energy. Sorry if that makes some physicists cringe.
 
  • #35
Astronuc said:
Well photons have no rest mass (but they do have momentum (p = E/c), so in one sense, they are pure energy. Sorry if that makes some physicists cringe.

Nah, the photon has chirality, it has this complicated relationship with the Z and W particles, and pretty generally its lack of mass doesn't keep it from having properties; gee, look at the way the photons behave in the delayed choice quantum eraser! For starters you have to be able to entangle them. Pure energy? Are you kidding?
 

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