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Scientists Propose Collider That Could Turn Light Into Matter
An anonymous reader writes "Imperial College London physicists have discovered how to create matter from light — a feat thought impossible when the idea was first theorized 80 years ago. From the article: 'A pair of researchers predicted a method for turning light into matter 80 years ago, and now a new team of scientists are proposing a technique that could make that method happen in the purest way yet. The proposed method involves colliding two photons — the massless particles of light — that have extremely high energies to transform them into two particles with mass, and researchers in the past have been able to prove that it works. But in replicating that old method, known as Breit–Wheeler pair production, they had to introduce particles that did have mass into the process. Imperial College London researchers, however, say that it's now possible to create a collider that only includes photons.'"
Aren't you supposed to "make light of the matter", and not the other way around?
Being bosons just means you can pack multiple quanta into the same state.
All particles interact (otherwise, how would we even know they "exist"?), and photons interact electromagnetically. That means that they can induce the vacuum to produce pairs of electrically charged particles: say, an electron and a positron. Usually, those particles are just quantum fluctuations or "virtual particles", living for a tiny fraction of a second due to Heisenberg uncertainty. However, if two photons have enough energy between them (at least equal to the mass-energy of the pair), they can give their energy to the electron and positron and turn them into real particles. That's what they want to do here: get two photons to give their energy to a virtual particle pair, making it real.
I believe the summary is confusing concepts. A 'proposal' for how to do something, but not actually having implemented the proposal to see if it actually works IS NOT the same as 'discovering how to do something'.
There is a huge, fundamental gap between
I suggest we try doing X to accomplish Y
and
I did X and accomplished Y
Sleep your way to a whiter smile...date a dentist!
But that wont happen because they'll ban the thing over irrational fear before the technology reach the point it can print a cup of earl grey.
Okay, let's say you want to make a cup of earl grey tea from energy alone. For simplicity's sake, let's pretend you are providing the cup and the only thing you need to create is 250 mL (~8 fl oz for those of us in the benighted US) of pure water at 100 C. I chose 0.95835 g/cm3 as the density of H2O @ 100 C.
Synthesizing that water from pure energy in a 100% efficient process that magically created only the appropriate molecules would require approximately 6,000 gigawatt-hours of energy, aka 2.15E16 J (hooray for e=m*c^2 being on-topic for once in forever). FWIW, the absolute minimum amount of energy required is equivalent to over 5 megatons of TNT .
For reference, the generating capacity of the entire United States is approximately 1,000 gigawatts . So, uh, in some mythical 100% efficient conversion of electricity to matter it would require the entire generating capacity of the United States for over 6 hours (line losses, oh my!) to produce the water for one cup of earl grey. If you want to stay true to concept, let's say your tea needs to be ready in 5 seconds. Okay, that represents 4.3 petawatts .
So, no, I doubt a ban will be what stands in the way of you getting your replicated earl grey.
Besides, anything that created that much power would be instantly weaponized.
If you assume we have a way to convert energy into matter with 100% efficiency, then it's not far fetched to assume we'd also have a way to convert matter into energy. So, you can save yourself all the calculations, and just grab 250 grams of waste products from the ship's waste disposal system, and turn them into a cup of Earl Grey tea.
So, uh, at that point why are you even bothering with a matter/energy conversion? Just use the cleaned, recycled water directly. I already have a machine that can "3D print" a cup of 95 C water, and all it requires is a water reservoir and a 1300 W heating element. I have to bring my own cup, but that was already stipulated.
What? How can you link a paper like that and completely not understand its contents? No, they did not create matter out of light. The important thing from that paper is that the light was frozen in place while it was traveling through the material. It's a nice experiment, but has absolutely nothing whatsoever to do with photon-photon interactions and creating of particle-antiparticle pairs. The word "mass" doesn't even appear in the paper, for example. The photon energies are eV level in that paper, and photon-photon interactions require billions times more. Like, gamma rays, not visible light.
You might argue, pedantically, that while the light was trapped in the sodium in that paper, the kinetic energy of the sodium atoms increased. And due to relativity, increase the kinetic energy of something also increases its mass. Well, you would be right, and that happens every time the sun shines on something and warms it up. But when you talk about creating matter from photons, they mean making brand new particles-- that is, making even the *rest mass* portion of their energy out of the photons-- not just speeding up existing particles. And that just cannot be done with light near the visible spectrum.
Good to see. The analogy to theoretical physics I use is, it's the difference between Imagining you are getting laid to getting laid.
I don't really use that analogy, it just occured to me and now i am sad.
Saying that they're publishing in an attempt to secure funding is the least insightful comment you could possibly make, because that’s precisely how expensive “serious science” gets done: you put your theory up for peer review in a publication like Nature Photonics, and if it’s sound then you go into the contest for funding an experiment. Using your logic we should’ve built the Large Hadron Collider before the theoretical merit in building it was confirmed; if you can’t see why that's a phenomenally stupid way to allocate finite resources then sorry, but I have to doubt you're clever enough to prove a conjecture theoretically, let alone practically.
Blank until
Or do you want to be stuck on earth where 50% of the population are morons?
Fixed that for you.
Regards,
The other 50%
Not at all. In science, there is just as much validity to "we did X but didn't get Y" as there is to "when we did X, Y was accomplished." In fact, Michelson and Morley are a prime example of "we did X but didn't get Y" in 1887, and they won the Nobel prize for it in 1907.
- W. Blaine Dowler
http://www.bureau42.com
I'm afraid that we've already got everything we need to make a much more comfortable society even with "just" the technology and resources we have now. That fact that we don't shows that something else is hard-wired into our biology: how to be complete and utter assholes.
I suspect even with completely free everything we'll still find ways to have taxes and rich and poor people.
Mostly random stuff.