Energy

[Qfwfq]

To show a more prominent example (and less connected with the day-to-day life) we can look at Uranium-235, it's mass added to a neutron which hits it, and compare it with the masses of the fission products. A difference in mass (called mass defect) is seen.

The trouble with this is that it's not easy to reverse, so it doesn't quite reach the goal Mercedes Benzene had in mind: that of changing other forms of energy into mass. It's much easier to heat something up and photosynthesis occurs all the time.

 

If you target iron nuclei in a particle accelerator, you could succeed in splitting it into smaller ones but many of the products could be unstable and it's hard to predict the final sum of masses. However, in hadronic diffraction at high incident energy, there are often so many products that some stable ones may occur and perhaps you're likely to get an outcome with less kinetic and more rest energy.

[ronthepon]

Ok, so to make weighable mass easily, we need to get something to move fast. Then the kinetic energy that is in it will increase it's mass. (verifiable if you use the relativity equations in a reverse direction)

[CraigD]

As several posters have noted, transforming energy into “virtual” relativistic mass is pretty easy - just accelerate ordinary matter, and let the consequences of Relativity do the rest. A large particle accelerator can do an impressive job of this, accelerating a stream of charged particles with a rest mass of micrograms until it masses over a hundred times that at a speed approaching the speed of light. Once these particles return to relative rest, however, all that “artificial mass” is transformed back into energy.

 

As near as I can tell, there are a couple of practical ways to transform energy of various kinds into “genuine” rest mass – the sort you could make into a paperweight, etc.

 

One way is to utilize electron capture, a process by which an electron and a proton combine to form a neutron. Since a neutron masses slightly (about 1.4*10^-30 kg) more than a proton and electron combined, and as long as you make sure to stick it in the right sort of atomic nucleus with some protons, is regular, stable matter, a technique that causes electron capture can be used to “manufacture” matter from energy.

 

Though you could, in principle, do this by just colliding electrons and protons, I’m unaware if this has ever actually been accomplished. Usually such collisions result in the proton disintegrating into its component quarks, which, unable to exist unpair with others in protons and neutrons, become a “jet” of exotic and ordinary hadrons (not much good for making paperweights)

 

A more promising way to cause electron capture is to use energy to accelerate a convenient particle (protons are stable, easy to move with magnets, and have plenty of mass), and collide it with some appropriate nuclei in such a way that you create an unstable, heavy element. If you do this just right, you can cause a condition where the only way the unstable atom can transmute into a stable one involves electron capture. Though I’ve never read of this actually being done, in principle, one could use such a technique to, for example, slightly increase the mass of a lump of lead by increasing it’s porportion of heavier isotopes from the usual (1% 204Pb, 24% 206Pb, 22% 207Pb, 53% 208Pb) to something like (1% 204Pb, 18% 206Pb, 18% 207Pb, 63% 208Pb). Do this to about 1,500,000 paperweights, and you could shave off enough from each to make another identical paperweight. You have manufactured matter using electron capture!

 

The other way is to utilize pair production, where a particle of energy (usually a gamma ray photon) changes into a particle of matter and its antiparticle (usually an electron and a positron). Quantum theory predicts that this happens constantly, but that the particle pairs recombine into the original photon so quickly that only extraordinary methods (such as Casimir effect experiments) can show it happened at all.

 

To use pair production in a practical matter manufacturing, you need a way to make sure the particle doesn’t get together with its antiparticle. To the best of my knowledge, the only people who’ve succeeded at this are some researchers at SLAC and CERN, who, since the mid 1990s, have succeeded in doing it by accelerating antiprotons to close to lightspeed, and shooting them past atomic nuclei to create electron/positron pairs, with a few of the positrons forming antihydrogen with the passing antiproton, rather than annihilating with the electron. They’ve managed to produce about 1/1,000,000,000,000 kgs of matter that way (actually, antimatter, since it’s way more interesting and useful than matter - though not for making paperweights!)

 

A better pair-production-utilizing energy-to-matter manufacturing technique might involve gravity instead of magnetic and nuclear force. In this scheme, just aim a stream of gamma photons close by something massive, and count on the slight difference in their initial velocity vectors and gravity to keep them apart. However, for this scheme to work well, “close by something massive” means something really massive, at least a neutron star, better yet a black hole. If you have a tame black hole available for engineering and manufacturing, though, making photons into ordinary matter begins to look pretty easy.

 

All said, the bottom line on energy-to-rest mass conversion is that, while theoretically and, to some extent, practically possible, it’s not of much practical use. There seems to be enought matter around for any practical need. Mass-to-energy conversion is very useful, and the focus of lots of research, but energy-to-matter conversion is more of a scientific curiosity.

[hallenrm]

So energy is the potential to bring about energy. We can't include energy in the genre of free existing things.

 

That is new for me.

 

No energy is the potential to bring about a change!

 

It is not a thing, free existing or otherwise, it is a concept, an idea, a mental construct of scientists!

 

If it is new for you, its good education you are getting at Hypography!!!

[sebbysteiny]

"Mass and Energy are concepts, and scientific concepts are created only once, in the mass conciousness of scientists!!"

 

Erm, I don't think we need to go into new age philosophical thinking and argue that nothing really exists to explain this. Mass and energy are physical things. If you don't believe me, just stand on the scales. You might tell yourself that mass is just a ficticious concept, but: the scales never lie :hammer:.

 

 

The answer to the question is quite simple. Yes. Anything in which energy is absorbed increases the rest mass: photosynthasis, electron capture, heating something, partical accellerators, hitting someone over the head with a baseball bat to name but a few.

[ronthepon]

No energy is the potential to bring about a change!

 

It is not a thing, free existing or otherwise, it is a concept, an idea, a mental construct of scientists!

 

If it is new for you, its good education you are getting at Hypography!!!

Oh sorry, that must have been a typing mistake! Sorry!