e=mc2, does this mean that we can make atoms out of energy?

[cameron marical]

energy=mass x circumfrence squared. yes ok, and the atoms and energy are the same thing? at least thats what einstein proposed, well, if we can take the energy out of an atom{i.e. atom bomb}, can we take the atom out of the energy. well, not take out, more like make out of.? if so, this can be used for alot of things, i know that this will take alot of energy, but, if we can supply it, then we can use these things on spaceships and make food and water and elements for repairs with this, and send these things to places like africa and solve world hunger by making food out energy. i know this will take alot of energy, but this is mostly future tense{hopefully neat future} and im assuming we have other forms of getting energy wich are very efficient, like fusion, and sending probes near the sun using modified solar panels and get huge amounts of energy from gamma and solar rays.

[ydoaPs]

energy=mass x circumfrence squared.

c=speed of light.

 

E²=m²c⁴+p²c²

 

Do you have any idea how much energy you're talking about?

[cameron marical]

ya, i do, but if we can solve that problem, than this can solve alot of other problems too. this is only in theory, im not saying we can do it now.

[npts2020]

IMO what you are asking is possible in theory but well beyond current technology and unlikely to be very efficient. Wouldn't it be simpler just to convert the matter you already have to the form you wish?

[swansont]

Scientists have made antihydrogen, so it's certainly possible. But since you make as much antimatter as matter (ignoring CP violation for the moment), all that antimatter is going to annihilate, and you end up with nothing extra. There's no point to it.

 

As far as making food and water, etc, you still have the same problem of assembling the elements from the protons and neutrons, so why not just start there?

[cameron marical]

could you explane antimatter? i dont fully understand the concept.

[Baby Astronaut]

could you explane antimatter? i dont fully understand the concept.

Here ya go.

 

http://particleadventure.org/frameless/antimatter.html

 

http://www.space.com/scienceastronomy/antimatter_sun_030929.html

 

http://www.wisegeek.com/what-is-antimatter.htm

 

http://www.positron.edu.au/faq.html

 

http://www.tech-faq.com/antimatter.shtml

[cameron marical]

why would it make equal amounts of anti-and normal matter? the big bang, according to us, says differently.

[swansont]

why would it make equal amounts of anti-and normal matter? the big bang, according to us, says differently.

 

That's because of charge-parity (CP) violation. What we've investigated shows a very small effect (why the universe is matter is one of the big unanswered questions)

 

From a practical standpoint (i.e. to a first-order approximation), you create equal amounts of matter and antimatter, because that and other conservation laws hold at that level.

[cameron marical]

oh, could this charge-parity be used in something like this?

[swansont]

oh, could this charge-parity be used in something like this?

 

Not really. It's a very small effect.

[kleinwolf]

[math]e=mc^2 [/math] could be a mnemotechnic for general relativity too :

 

e=energy density

m=a constant depending on the gravitational constant and the celerity of light

c^2=curvature squared

[lakmilis]

I do like these who is GR? and circumference squared.. cameron

 

Spend some time on wiki , before trying to figure out things from a concept you don't quite grasp. However, you do have a very keen explorative mind.. that is very good to have

[cameron marical]

thanks. will do.

[Mr Skeptic]

Yes, we can make equal parts matter and antimatter from energy, which is basically what particle accelerators are for -- the accelerated particles are the energy source for making high-energy particles. In practice though, it is far more useful to convert matter to energy, as do nuclear fusion in the sun and nuclear fission power plants.

[GDG]

energy=mass x circumfrence squared. yes ok, and the atoms and energy are the same thing? at least thats what einstein proposed, well, if we can take the energy out of an atom{i.e. atom bomb}, can we take the atom out of the energy. well, not take out, more like make out of.? if so, this can be used for alot of things, i know that this will take alot of energy, but, if we can supply it, then we can use these things on spaceships and make food and water and elements for repairs with this, and send these things to places like africa and solve world hunger by making food out energy. i know this will take alot of energy, but this is mostly future tense{hopefully neat future} and im assuming we have other forms of getting energy wich are very efficient, like fusion, and sending probes near the sun using modified solar panels and get huge amounts of energy from gamma and solar rays.

 

Yes, matter and energy are different forms of the same stuff. Matter is much, much more concentrated. Take a look at the antimatter bomb thread: the amount of energy equivalent to a 1 kg mass (of anything) is the amount of energy you would get out of a 210 megaton explosion (4X the size of the largest nuclear device ever detonated). That is a lot of energy to try and stuff back into a 1 kg box. I doubt that anyone is likely to try it

 

The second problem is that we have no way right now of controlling what kind of matter we would get. Particle accelerators focus huge energies in a very small space: some of that energy gets converted to matter -- and almost instantly back into energy again. Most of the matter comes out as highly unstable particles, which decay into other particles, which may ultimately decay into protons, electrons, neutrinos, and photons. Very difficult to accumulate any mass that way...

[coke]

wait a sec...

 

i thought nucear bombs took energy due to the higher stability and nuclear binding force of products than the starting material (i.e. hydrogen > helium, uranium > thalium, lead, etc.)

 

Not because there is any change in mass (at least not before talking about the sub-neutron levels)

 

Antimatter, on the other hand, that I know releases energy destroying mass...

[GDG]

The reference to the bombs was just convenient, as a measure of the energy required to make a kg of mass. An "antimatter bomb" would convert 100% of its mass into energy: if you were to make a kg of mass, you would need that much energy. 210 megatons is about 8.8 x 10^8 gigajoules.

[coke]

By the way... i wonder

 

If you have a very strong electromagnetic field... and you pass a beam of light or gamma rays through it, can you split up the photons into matter and antimatter?

 

That would be a good example of making atoms out of energy.

[lakmilis]

coke: no... I can not see any conventinal sense of the concept

electromagnetic field' and it being so 'lewd' it can turn photons of various energies into antimatter and matter... it does nto follow the stdard model tbh. (severians field).

[swansont]

A photon splitting up into a particle/antiparticle pair does not conserve momentum (assuming it conserves energy). You need something around to recoil for the pair production to occur.

[coke]

Well ok, an electron + positron = gamma ray, right? (and electrons are attracted to positrons by magnetic attraction)

 

So cant this be done the other way around?

 

I mean there are easier ways to get positrons, I know...

[swansont]

Well ok, an electron + positron = gamma ray, right? (and electrons are attracted to positrons by magnetic attraction)

 

So cant this be done the other way around?

 

I mean there are easier ways to get positrons, I know...

 

Two gammas (or more), and the attraction is electrostatic. But yes, a gamma of at least 1.02 MeV can produce an electron/positron pair

[coke]

you can make positron + electron from gamma rays!

or can you? it also draws some nucleus, i wonder if it gets changed by the reaction...

 

check out this page...

 

but apparently it has nothing to do with electromagnetic field...rather just 1.02 MeV high energy photons, like swanston said

although i suppose you can use a field to keep electrons and positrons apart afterwards...

 

actually it seems like a very good way to generate positrons, and for that case, antimatter...

the titan laser creates huge amounts of antimatter from sheets of gold (see here)

Edited April 6, 2009 by coke

[Mr Skeptic]

Yes, however you need another particle to conserve momentum.