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How Richard Feynman's Diagrams Almost Saved Space (quantamagazine.org)
An anonymous Slashdot reader shares a fond remembrance of Richard Feynman written by Nobel prize-winner Frank Wilczek, describing not only the history of dark energy and field theory, but how Feynman's influential diagrams "embody a deep shift in thinking about how the universe is put together... a beautiful new way to think about fundamental processes".
Richard Feynman looked tired when he wandered into my office. It was the end of a long, exhausting day in Santa Barbara, sometime around 1982... I described to Feynman what I thought were exciting if speculative new ideas such as fractional spin and anyons. Feynman was unimpressed, saying: "Wilczek, you should work on something real..."
Looking to break the awkward silence that followed, I asked Feynman the most disturbing question in physics, then as now: "There's something else I've been thinking a lot about: Why doesn't empty space weigh anything?"
Feynman replied "I once thought I had that one figured out. It was beautiful..." then launched into a "surreal" monologue about how "there's nothing there!" But Wilczek remembers that "The calculations that eventually got me a Nobel Prize in 2004 would have been literally unthinkable without Feynman diagrams, as would my calculations that established a route to production and observation of the Higgs particle." His article culminates with a truly beautiful supercomputer-generated picture showing gluon field fluctuations as we now understand them today, and demonstrating the kind of computer-assisted calculations which in coming years "will revolutionize our quantitative understanding of nuclear physics over a broad front."
Looking to break the awkward silence that followed, I asked Feynman the most disturbing question in physics, then as now: "There's something else I've been thinking a lot about: Why doesn't empty space weigh anything?"
Feynman replied "I once thought I had that one figured out. It was beautiful..." then launched into a "surreal" monologue about how "there's nothing there!" But Wilczek remembers that "The calculations that eventually got me a Nobel Prize in 2004 would have been literally unthinkable without Feynman diagrams, as would my calculations that established a route to production and observation of the Higgs particle." His article culminates with a truly beautiful supercomputer-generated picture showing gluon field fluctuations as we now understand them today, and demonstrating the kind of computer-assisted calculations which in coming years "will revolutionize our quantitative understanding of nuclear physics over a broad front."
... that it's an awesome article and a totally cool picture. Saves me some reading. Next!
What evidence do you have of this ?
Perhaps he'll finally be able to answer the question about whether hell is exothermic or endothermic.
"Go to Heaven for the climate, Hell for the company..." -- Mark Twain
When it says 'almost saved space' I don't think they are refering to the 'saving' thtat Jesus does
Look the big issue with particle physics is time going backwards. Feyman put a nice diagram on it, but its just wrong. The niceness of the diagram causes you to fail to question the underlying assumption.
We have lots of systems where time *appears* to go backwards, and they are *observational* effects, not real effects.
So for example, lightning appears to travel from ground to sky often. Yet the sky is discharging to the ground, not the ground to the sky. Is this lightning going backwards in time? No. We understand this, because we realize that visible lightning is the plasma created as the discharge heats the air. The discharge is already happening before the plasma is created, and the plasma can begin from any hot point in the discharge. The ground and sky are usually quite fixed points, so the discharge starts from one or other.
i.e. the observation appears to go backwards in time but because we understand what's going on, we realize its an observation not real.
Now we know particle physics cannot send particles backwards in time. A simple logic test tells you that. For example if a particle splits in two, one going backwards in time, we can detect that, kick away the original particle, so it could not have split, so its subparticle could not have gone back in time to be detected.... i.e. a paradox.
So any effects you view in the cloud chamber that appear to go backwards in time do not, they are observation effects only.
Now certain 'proofs' are cited as proof of time travel. e.g. Entanglement. And you can realize this yourself by CRITICALLY looking at the various entanglement experiments. For entanglement to be real it needs time travelling particles/waves. When you measure a photon and it behaves like a wave, the photon needs to have gone back in time and change its properties so that every earlier split photon from it, is also correctly behaving like a wave.
So for example you examine the Delft entanglement 'proof': Electron A makes Photon AP, Electron B makes Photon BP, the Photons AP and BP are 'entangled'. The the spin of Electron A is measured and the spin of Electron B is measured. Is there correlation between the two? i.e. is entanglement real? No, they behave totally independently. The experimenters then filter the experimental set. Now they measure AP and BP and determine they are "the same in all possible ways". If they're not, they discard the result and only keep results where they are the same.
Is Electron A spinning like Electron B? Yep... hurrah... we've 'proved' entanglement.... except that comes from this experimenter filtering.
So entanglement isn't real, the photon really has no idea whether the matter its interacting with is a test of wave or particle, and has no way of going backwards in time to change it's behavior.
So, no time travelling entanglement, and you can't cite it as proof of time travelling particles.
So laud Feyman all you like, but don't try to canonize his work as some sort of insightful fundamental truth, it's not. It's a continuation of the basic Niels Bohr flawed thinking.
I.....*almost* saved..?
It saves a lot of space too. Just so you know it isn't just Feynman doing all the cool stuff.
Mr Feynman's diagrams are of course an extremely useful tool, but space existed well before the diagrams and well before Richard himself did. Space will continue to exist for quite some time after his passing too.
Space never cared about any of this. It just was.
Stupid headlines are stupid.
Aww, that was our Dick
You do?
Why should my soul care what the temperature is when it seems less worried about the lack of oxygen.
Nullius in verba
From the summary, you could be excused for thinking that the article it's talking about is rubbish. You'd be wrong. The subject of the mass density of space is a lot deeper than you might think if you're not a theoretical physicist. The article is actually remarkably good at laying out and discussing the problem. In fact, the subject is a bit like Feynman diagrams themselves: initially they look like simple cartoons (which they are) that can't have any deep meaning ... but they can. Definitely worth a read if you have an interest in, and basic understanding of, the modern ideas regarding particles and fields.
I'm really looking forward to joining Feynman, but how can we burn for eternity? Wouldn't that require us to be of infinite mass and produce an infinite amount of heat? Show your math.
At the end of the paper, we realize that decades after Feynman, we still not know why empty space does not weight anything, while at the same time it is full of particles created by quantum fluctuation.
I don't know how much space Feynman diagrams saved but that's certainly nothing compared to Huffman coding.
Better to be a free man (or woman) in hell than a slave in heaven.. :) baaa... baaa....
Below the speed of light Special Relativity is one of the most accurate theories in physics - above the speed of light..