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Can matter be destroyed?

DangerousBeliefs

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DangerousBeliefs
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Kumar said:


"There is no proof. There is only assumption and dedication by its various followers, but no proof that a deity ever existed, or created the universe, or is currently influencing our reality."

Then, how universe is created? What is the basis of its creation, or tion of earth orcreation of livings?
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Kumar got me thinking...

Has anyone in science been able to destroy matter/energy?

Is there any observable effect that destroys anything in the Universe?

If there is no real destruction of matter/energy, then why do people think there must be a creation of said matter/energy?
 
DangerousBeliefs said:


Kumar got me thinking...

Has anyone in science been able to destroy matter/energy?

Is there any observable effect that destroys anything in the Universe?

If there is no real destruction of matter/energy, then why do people think there must be a creation of said matter/energy?
Click to expand...
Thanks DB. It is highly relevant topic. Basically, We should always try to research role of matter & energy in the first place for any unclear aspect. It is our first BASIC to know.
 
Short answer no. Long answer possibly, with a but, and a better set of definitions.
 
DangerousBeliefs said:


Kumar got me thinking...

Has anyone in science been able to destroy matter/energy?

Is there any observable effect that destroys anything in the Universe?

If there is no real destruction of matter/energy, then why do people think there must be a creation of said matter/energy?
Click to expand...

What is anti-matter (I have heard the term) - maybe this destroys matter?
More than likely, matter transforms, and this transformation is seen as a destructive\creative process.
While the subject of 'what made the big bang happen' is interesting, the subject of what the result of that event has done is doing and will continue to do, is perhaps more interesting.
Your question is interesting and I think that if the universe had just always been, then there would be less problems for people in understanding what it is.
The fact that there was an apparent beginning, tends to get the intelligent mind wondering what mighty thing was able to effect this unimaginably awesome thing we call the universe, into existence.
If there were no intelligence around which could appreciate the universe, would it exist?
 
Upper half of big bang cycle may represent creation phase & lower half as destruction phase. But it is a creation or destruction of basic matter/energy, is bit doubtful. It can be a conversion from matter to energy or opposite. It can also be a conversion from basic(micro) to gross(macro) & opposite.
 
I seem to remember being told during a A-level chemistry class that a very small amount of matter is destroyed during a nuclear explosion. Don't know whether that is really the truth of the matter, though. It seems to me that it's more likely a mathematical error, but I'm no expert.
 
richardm said:
I seem to remember being told during a A-level chemistry class that a very small amount of matter is destroyed during a nuclear explosion. Don't know whether that is really the truth of the matter, though. It seems to me that it's more likely a mathematical error, but I'm no expert.
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It is destoryed. It is ceonverted to energy. The forumlar for working out the amount of energy released by the destruction of mater is E=mc^2.
 
geni said:


It is destoryed. It is ceonverted to energy. The forumlar for working out the amount of energy released by the destruction of mater is E=mc^2.
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Ah, yes, it was in the context of conversion to other forms that it came up. The matter is destroyed and converted to energy, but the amount of energy produced is slightly smaller than you'd expect from the amount of matter destroyed. A tiny amount of it is lost.

Don't quote me on any of this; it was a long time ago, and I may be remembering wrongly (or, indeed, the lecturer might have been mistaken).
 
richardm said:
Don't quote me on any of this; it was a long time ago, and I may be remembering wrongly (or, indeed, the lecturer might have been mistaken).
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Sounds to me like you are talking about the sums that made phyercists decide that nutrinos exist (without them you do get the error that you are talking about).
 
Re: Re: Can matter be destroyed?

Navigator said:


What is anti-matter (I have heard the term) - maybe this destroys matter?

*snip* to remove irrelavant ramblings
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From my understanding, when anti-matter mets matter, vast amounts of energy are released... so nothing is destroyed.

Again, I have to say, if we cannot destroy matter/energy then why must we think there is a creation of it?
 
Re: Re: Can matter be destroyed?

Navigator said:
What is anti-matter (I have heard the term) - maybe this destroys matter?
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Matter, at least the matter we are made of, consists of atoms made of protons, neutrons and electrons. Antimatter consists of atoms made of particles with equal masses but opposite charges to matter. Interestingly, this means that there is no such thing as an anti-neutron.

When matter and antimatter meet they annihilate giving out huge amounts of energy.
 
Wrath of the Swarm said:
Yes, there are antineutrons. They can be made by combining an antiproton and a positron.
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In exactly the same way that you make a neutron from a proton and an electron, yes, but surely you end up with a neutrally charged particle with the same mass as a neutron, ie a neutron!
 
wollery said:
In exactly the same way that you make a neutron from a proton and an electron, yes, but surely you end up with a neutrally charged particle with the same mass as a neutron, ie a neutron!
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Nope.

A neutron consists of three quarks: up, down, down. All have mass 1/3. Up quarks have charge 2e/3 and down quarks -e/3 giving a charge of 0 for a neutron.

An antinuetron consists of three anti-quarks: anti-up, anti-down and anti-down. All have mass 1/3. The anti-up quark has charge -2e/3 and the anti down quarks each have charge e/3 giving a charge of 0 for an anti-neutron.

Charge and mass are not the only properties of particles. The anti-neutron is identifiable through a different quantum number called the baryon number. Neutrons have baryon number 1 and anti-neutrons have baryon number -1.

Basically, this means that while they look similar on the outside, if you break the two particles up you get two sets of oppositely charged particles and anti-particles.


Edited to add: or you could just follow the link from scotth above.
 
Huntsman said:
Just to add my 2 cents, don't anti-particles also have an opposite spin? Or is this the smae thing as saying it's baryon number is -1? I seem to recall baryon number having something to do with spin, but it's been a while for me.
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No, particles have the same spin as their corresponding anti-particles. The baryon number was brought in when it was noticed that certain decays (proton decay) are never observed. Conservation of baryon number was therefore postulated to basically say that certain particles can't change into other particles.

Or something like that.
 
Okay, now I have to ask for clarification.

I KNOW I've heard that bit about spin being opposite. Here, I found a link from Lawrence Radiation Laboratory about anit-matter with the following quote:
In the 1950's, physicists at the Lawrence Radiation Laboratory used the Bevatron accelerator to produce the anti-proton, that is a particle with the same mass and spin as the proton, but with negative charge and opposite magnetic moment to that of the proton.
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Source at LRL

Aren't magnetic moment and spin the same thing? Is there new information that spin is identical in both, or that it is immaterial? Since particles and anti-particles must be produced in pairs (Link to CERN information site ) it would seem that spins must be opposite due to conservation laws. Is the spin differnt from one proton to the next, and only opposite for members of a pair?

Hmm, okay, I found
this link to Scientific American that seems to support what you said...linear and angular momentum (including spin and energy) are identical, everything else is opposite. Now I'm completely confused. And my high school physics book, and the physics book for my sophmore physics class, were apparantly wrong. Or maybe I'm just getting senile a bit early.

Nevermind. Heh. I'll go ahead and post this, though, just for the links if anyone else is interested :)
 
Thanks guys, particle physics was never one of my strong subjects. How I passed the undergrad course in it I'll never know (although it might have had something to do with the amount of work I put into it!).
 
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