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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.'"
Dudes, you are solving the problem, in reverse: we want instant energy from dirt.
Table-ized A.I.
Aren't you supposed to "make light of the matter", and not the other way around?
I preface this with an admission that my serious physics studies were like 25 years ago now, but - photons are bosons, how can they "collide"?
Perfectly Normal Industries
These scientist haven't discovered how to create matter from light. That's already standard theory. What they have done is devised a clever experiment to test this.
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!
My first thought was 3d printer. Imagine deposing one atom tick layers of any element in any shape. eg; The Star Trek synthesiser.
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.
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.
No matter the result, they'll surely be able to make grant money go poof at the speed of light.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
The goal is to verify our understanding of quantum physics, not to create matter.
You have forgotten that no process will be perfectly efficient unless someone invents some new thermodynamics. You are talking about "waste" of a few hundred grams of easily-recycled organic matter (or water) by channeling megatons worth of energy. What's a few percent of waste heat generated on a process that is pumping quadrillions of joules around? Entropy always gets its pound of flesh.
But hey! We *saved* some water we could have, you know, could have distilled into purity using today's technology by using an infinitesimal amount of that waste heat that would be inescapably generated by pumping around those megatons of energy for pointless matter/energy conversions!
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%
Back in 1997 at Stanford green laser light was smashed into gamma rays to produce matter.
Scientists Use Light to Create Particles
Photons of light from the green laser were allowed to collide almost head-on with 47-billion-electronvolt electrons shot from the Stanford particle accelerator. These collisions transferred some of the electrons' energy to the photons they hit, boosting the photons from green visible light to gamma-ray photons, and forcing the freshly spawned gamma photons to recoil into the oncoming laser beam. The violent collisions that ensued between the gamma photons and the green laser photons created an enormous electromagnetic field.
This field, Melissinos said, "was so high that the vacuum within the experiment spontaneously broke down, creating real particles of matter and antimatter."
This breakdown of the vacuum by an ultrastrong electromagnetic field was hypothesized in 1950 by Dr. Julian S. Schwinger, who was awarded a Nobel Prize in physics in 1965.
Emphasis mine.
Thus, we do know that we can create matter by colliding photons already. The new experiment proposed could be useful because it does not require the electron-photon collision near the detector in order to produce the gamma photons and subsequent light on light reaction. They'll be firing gamma rays through a cylinder full of black body radiation. A gamma-gamma collision would be more interesting, IMO. The new gamma or black-body radiation collision experiment should be of even lower energy than the gamma and green laser collisions which produced matter in 1997.
Why even go for a lower energy apparatus than what has been demonstrated at all? Simple: To verify the minimal energy level required to make the vacuum puke.
Total energy output of the sun per second: 3.8×10^26 J (source: wikipedia)
This amounts to 4.22×10^9 grams per second,
or about 18 million cups of tea per second.
If Pandora's box is destined to be opened, *I* want to be the one to open it.
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
Current thermodynamics works fine enough for what is suggested. Thermodynamics allows for next to ideal conversion.
Gotcha. So, in order to avoid boiling some water to distill it to purity, you're going to be doing a matter/energy/matter conversion. In order to come out ahead of using a simple boiler, your ~9 petawatt (two conversions in the requisite time doubles the power) process is going to need to be 99.99999999% efficient or so.
Even a 99% efficient process would dump 90 terawatts of waste heat. The waste heat of your process would represent approximately 1/10 of the power of an average hurricane. Remember, you're claiming we would do this in order to "save energy" by not distilling a quarter liter of wastewater.
In summary: just because science develops a method that allows something to be done does not imply it will ever be the favored technology. We developed the means to create gold via atomic bombardment a long time ago, and that process will never supplant gold mining.
And it's cool to think that, maybe, when you have a warp core that powers a space ship going FTL with many millions of petawatts of energy, some star trek technology like replicators might come true :)
True, but somehow I doubt that anyone will ever be glib while wielding the power of the entire generating output of the Sun, for example (call that 100 billion petawatts). The power at that scale could destroy entire solar systems if a mishap or violent use were to occur.
If you weren't aware of the Kardishev scale, you might find it intriguing to consider the implications of a Type II civilization wielding the power of the entire Sun or to think about what a Type III civilization could accomplish.
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.
Not entirely devoid, no, but in my experience (as a former researcher; still have the CERN employee ID card) there is still some that is free of politics. The fact that results need to be reproducible to be accepted helps. The main concern is funding. As long as you can confidently tell your backers that there is money to be made either way, or find different backers with vested interests in different results, there is no pressure to fudge results. In fact, the project I worked on (ATLAS) had no outside input asking for bias in results that I could see in any way, shape or form. Of course, if that was the case universally nobody would question vaccines, but it still happens often, especially in fields like particle physics (which this article is talking about) in which application is so far down the road that most financial backers really are looking for the spinoff technology it takes to produce the result moreso than the result itself.
- W. Blaine Dowler
http://www.bureau42.com