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Patrick2568422

Could proton decay be caused by strings losing their vibrations?

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We know that some protons have been losing their charge, turing into neutrons, and as far as I know, we haven't worked out why. But string theory, which I am skeptical of, says that the string vibrations cause the charge of the particles. It is impossible for the strings to vibrate for ever surely, so maybe when they start to slow down in vibration, the protons lose their charge.  

Sorry if this is kind of a stupid question. 

Edited by Patrick2568422

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You are skeptic to string theory but wonder if a change in string vibration is causing proton decay?

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34 minutes ago, Juicy6 said:

You are skeptic to string theory but wonder if a change in string vibration is causing proton decay?

It is not that I am skeptic of string theory, it is more that I think loop quantum gravity is better. I am trying to be open minded and I am researching both theories before making my final decision.  

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surely any loss of vibration would be immediate since the vibration is itself quantised ? No tail off there.

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7 hours ago, Patrick2568422 said:

We know that some protons have been losing their charge, turing into neutrons, and as far as I know, we haven't worked out why. But string theory, which I am skeptical of, says that the string vibrations cause the charge of the particles. It is impossible for the strings to vibrate for ever surely, so maybe when they start to slow down in vibration, the protons lose their charge.  

Sorry if this is kind of a stupid question. 

Proton decay has not been observed (unless you know something I don't).

In string theory there are no actual vibrating bits of string - they don't run out of energy or "slow down".

I share your scepticism, though possibly for different reasons.

Edited by acey

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2 hours ago, acey said:

Proton decay has not been observed (unless you know something I don't).

In string theory there are no actual vibrating bits of string - they don't run out of energy or "slow down".

I share your scepticism, though possibly for different reasons.

I watched a documentary on string theory and they said that the vibrations within the strings caused the properties in the particles such as charge.  

I am sceptic mainly due to Occam's razor. Loop quantum gravity accepts less circumstances. Why are you sceptic?

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2 hours ago, acey said:

Proton decay has not been observed (unless you know something I don't).

In string theory there are no actual vibrating bits of string - they don't run out of energy or "slow down".

I share your scepticism, though possibly for different reasons.

Agreed proton decay has been looked for but not found. Currently neither string theory or loop quantum gravity have made any predictions that have been observed.

Regards Andrew 

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6 minutes ago, andrew s said:

Agreed proton decay has been looked for but not found. Currently neither string theory or loop quantum gravity have made any predictions that have been observed.

Regards Andrew 

I always thought that proton decay was when a proton loses its charge and turns into a neutron. 

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7 minutes ago, Patrick2568422 said:

I always thought that proton decay was when a proton loses its charge and turns into a neutron. 

What is the mass of a proton? What is the mass of a neutron?

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8 minutes ago, Patrick2568422 said:

I always thought that proton decay was when a proton loses its charge and turns into a neutron. 

Your right you can get inverse beta decay. I was thinking of a proton decaying say via an intermediate meson into gamma rays as predicted by GUT. Beta and inverse beta decay is currently explained by the standard theory.

Regards Andrew 

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1 minute ago, andrew s said:

Your right you can get inverse beta decay. I was thinking of a proton decaying say via an intermediate meson into gamma rays as predicted by GUT. Beta and inverse beta decay is currently explained by the standard theory.

Regards Andrew 

what is the explanation? 

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2 hours ago, acey said:

Proton decay has not been observed (unless you know something I don't).

In string theory there are no actual vibrating bits of string - they don't run out of energy or "slow down".

I share your scepticism, though possibly for different reasons.

 

18 minutes ago, Patrick2568422 said:

I watched a documentary on string theory and they said that the vibrations within the strings caused the properties in the particles such as charge.  

I am sceptic mainly due to Occam's razor. Loop quantum gravity accepts less circumstances. Why are you sceptic?

Will say that of the assorted talks I have managed to get to at places like RAS ans BAA and others that talks seem to fall into 2 general catagories.

1 = It is a presentation of the latest findings and situation, say Plank or Gaia.

2 = It is a persons pet theory and it is presented as complete and utterly true and correct, but there is no proof or evidence to back it up.

One on partical physics fell into (2) and sounded utterly convincing, this theory "X" was a consequence of "A", and X was explained in detail as a consequence of A. Out of interest I went and search a bit more on it to find that not only was there no evidence of X but there was no evidence of A either. People will present something as if it completely true and correct and on a program they will not keep saying "Well if this precursor is correct then what we are saying could also be right", they have to present as if 100% true, proven and correct.

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1 minute ago, Patrick2568422 said:

what is the explanation? 

Google inverse beta decay. I am not a specialist in particle physics but I know it is used in detecting electron anti neutrinos. It can also happen in heavy nuclei without an incident neutrino.

Regards Andrew 

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9 minutes ago, George Jones said:

What is the mass of a proton? What is the mass of a neutron?

Since a proton has less mass than a neutron, a free proton, on its own, cannot decay into a neutron. A free neutron, can, however, decay into a proton.

Let's do this case first. After that, proton into a neutron.

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In a certain of units, the mass of a proton is 938.3, and the mass of a neutron is 939.6. (Which units?).

Consider

neutron -> proton

in a reference frame in which the neutron is at rest.  In relativity, there can be transformations between energy and mass, so this process can conserve mass/energy if the proton is moving, and hence has mass and kinetic energy.

This process does not conserve electric charge, as the total electric charge on the left side of the above process is zero, while the electric charge on the right is +1.

Try

neutron -> proton + electron

Now, mass/energy and electric charge can be the same on both sides of this process, i.e., can be conserved.

There is still a problem, though. Lepton number is different on the two sides of the process. A lepton is a particle that does not feel the strong nuclear force, and that has a certain type of spin. Since both neutrons and protons feel the strong nuclear force, they are not leptons, and they both have lepton number zero. An electron is a lepton, because it does feel the strong nuclear force, and it has the right type of spin. The lepton number of an electron is plus one. Consequently, the lepton number on the left is 0, while lepton number on the right side of the process is 0 + 1 =1.

Try

neutron -> proton + electron + anti-neutrino

A neutrino is also a lepton with lepton number +1, so an anti-neutrino has lepton number -1. Now mass/energy, electric charge, and lepton number are all conserved, i.e., are the same on both sides of the process.

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33 minutes ago, George Jones said:

In relativity, there can be transformations between energy and mass, so this process can conserve mass/energy if the proton is moving, and hence has mass and kinetic energy.

Yes but (!) you have to conserve momentum so you can't easily get the energy this way.

Protons are common in space and stable while a free neutron decays with a half life of just over 10 minutes while the half life of the Proton is estimated at 10^34 years.

Regards Andrew

Edited by andrew s
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On 2017-05-30 at 12:14, andrew s said:

Yes but (!) you have to conserve momentum so you can't easily get the energy this way.

You're right, I also should have considered (spatial) momentum. This prohibits a single heavier free particle at rest from decaying into a single lighter free particle in motion.

 

On 2017-05-30 at 10:51, Patrick2568422 said:

what is the explanation? 

Standard quantum field theory together with the standard model of elementary particles explains how a protons can change into neutrons.

 

On 2017-05-30 at 11:41, George Jones said:

neutron -> proton + electron + anti-neutrino

Just as maths allows changing A = B + C + D into A - C = B + D, physics allows the electron to be "taken to the other side" in the above process. When this is done, the electron becomes an antimatter electron (positron) "on the other side" (the equivalent of C changing to -C in the maths example). Then,

proton + anti-neutrino -> neutron + positron

when the anti-neutrino is energetic enough. This is the inverse beta decay to which Andrew referred above.

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