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Is particle physics dead, dying, or just hard?

quantamagazine.org

321–330 of 408 posts

Re: Is particle physics dead, dying, or just hard?

#321

Earlier quoted context omitted.

What would the cost of the “next machine” be? Is it going to be tens of billions or can we make progress with lesser money. If it is going to be tens of billions, then maybe we need to invest in engineering to reduce this cost, because it’s not sustainable to suspend thirty years, tens of billions for every incremental improvement.

This kind of slow, incremental improvement that costs tens of billions of dollars and takes decades gave us the microchips that ultimately enabled you to type this comment on your phone/computer. The return on that investment is obvious. But it is not just about making money: The entire field of radiation therapy for cancer exists and continues to improve because people figured out ways to control particle beams with…

Jack Kilby at Texas Instruments and Robert Noyce at Fairchild did not require tens of billions of dollars. Sherman Fairchild invested 1.3 million and the treacherous eight each put in $500. Fairchild did have the right to purchase the firm for $3 million, which of course he exercised. Similarly, Shockley's lab was funded by a $1 million grant in the 50s.

There is a lot of handwaving going on here to justify the incredibly cheap, mostly privately funded investments that launched the computer generation with the massively expensive, extremely gradual gains we are making now with particle accelerators. Part of it is that people just can't imagine how little was invested in R&D to get these stunning results, given how much we have to invest today to get much less impressive results, so they just assume that semiconductors could not have been invented without tens of billion dollars of research.

There is diminishing returns, just as a 90nm process is really all you need to get 90% of the benefits of computerization -- you can drive industrial automation just fine, all the military applications are fine, etc. But to go from a 90nm process to a 3nm process is an exponential increase in costs. In a lot of fields we are at that tail end where costs are incredibly high and gains are very low, and new fields will need to be discovered where there is low hanging fruit, and those fields will not require "tens of billions" of dollars to get that low hanging fruit.

Even with particle accelerators, SLAC cost $100 million to build and generated a massive bounty of discoveries, dwarfing the discoveries made at CERN.

To pretend that there is no such thing as a curve of diminishing returns, and to say that things have always been this way is to not paint an accurate picture of how science works. New fields are discovered, discoveries come quickly and cheaply, the field matures and discoveries become incremental and exponentially more expensive. That's how it works. For someone who is in a field on the tail end of that process, it's not good history to say "things have always been this way and have always cost this much".

Re: Is particle physics dead, dying, or just hard?

#322
post #219

Earlier quoted context omitted.

EUV lith would have absolutely been achieved if LHC wasn't ever built.

Lhc mastered high vacuum, high precision lens from zeiss, precision lasers, specialized magnets which are needed by euv lith. So would have been delayed.

EUV uses mirrors rather than lenses, and the precision surfaces on those are something that more likely came out of space programs. But honestly, I have no problem with throwing a few billion at basic science that might go nowhere. It's a drop in the ocean compared to war and corporate welfare.

Re: Is particle physics dead, dying, or just hard?

#323
post #193

Earlier quoted context omitted.

> Absolutely not Engineers not being able to fathom that by building this huge-ass and complicated machines to answer questions about the fundamentals of nature, other problems are solved or new things are invented that improve and change our life will never not be funny to me

Just as funny as armchair science enthusiasts not being able to fathom that research budgets are limited and it makes sense to redirect them into other, more promising fields when a particular avenue of research is both extremely expensive and has shown diminishing returns for decades.

Real scientists don’t call others armchair scientists, it’s just belittling. Do you resort to ad hominem because you feel like your argument is not strong enough, so you have to try to attack the person as well?

Re: Is particle physics dead, dying, or just hard?

#324
post #142

Earlier quoted context omitted.

Microchips? A lot of quantum physics is applied here from the top of my mind.

Quantum mechanics is relevant to humanity because we build things which are very small. General relativity is not, because we're more or less incapable of actually doing things on a scale where it matters.

General relativity is pretty relevant to GPS satellites.

Re: Is particle physics dead, dying, or just hard?

#325
post #38

Earlier quoted context omitted.

Even better, there are the "nightmare" scenarios where dark matter can only interact gravitationally with Standard Model particles.

Personally—and this is where I expect to lose the materialists that I imagine predominate HN—I think we are already in a nightmare scenario with regard to another area: the science of consciousness. The following seem likely to me: (1) Consciousness exists, and is not an illusion that doesn't need explaining (a la Daniel Dennett), nor does it drop out of some magical part of physical theory we've somehow overlooked u…

Yeah - the nightmare situation doesn't exist if you take a materialist approach. Maybe that's evidence for it?

Re: Is particle physics dead, dying, or just hard?

#326

It's basically the opposite situation from 150 years ago. Back then, we thought our theory was more or less complete while having experimental data which disproved it (Michelson-Morley experiment, Mercury perihelion, I am sure there are others). Right now, we know our theories are incomplete (since GR and QFT are incompatible) while having no experimental data which contradicts them.

>GR and QFT are incompatible

I did physics at uni and kind of dropped out when it got too hard.

I've long guessed the incompatibility is because the maths is just too hard for human brains, though I'm probably biased there, and we'll get a breakthrough when AI can handle much more complex maths than us. Probably not so long till we find out on that one.

I once tried to write a simplified explanation for why a spin-2 quantum theory naturally results in something like general relativity and totally failed - man that stuff's hard.

Re: Is particle physics dead, dying, or just hard?

#327
post #189
post #185

Earlier quoted context omitted.

> The latest ones cost billions and have confirmed a few things we already thought to be true. Yes, but we had hopes that it would lead to more. And had lead to more, something only known to be false in hindsight, who knows where that would have ended us up? What if it upended the standard model instead of reinforcing it? > Absolutely not. What are we supposed to do then? As humans, I mean. No one knows why we're her…

>I'm not arguing for mindlessly building bigger accelerators, and I don't think anyone is But you are and they are. Just by the comments here its clear that even suggesting not to use untold billions on maybe pushing theoretical physics a little forward is meet with scorn. The value proposition either, in knowledge or technology, is just not well argued anymore besides hand waving.

Or, you know, we have read the physics case and are of the opinion that it's worth it. Have you?

Re: Is particle physics dead, dying, or just hard?

#329

Earlier quoted context omitted.

I don't understand what is wrong with pessimism. That's not a valid critique. If someone is pessimistic but his description of the world matches REALITY, then there's nothing wrong with his view point. Either way this is also opinion based. There hasn't been a revolutionary change in technology in the last 20 years. I don't consider smart phones to be revolutionary. I consider going to the moon revolutionary and catc…

My critique is not due to pessimism, it is due to afactuality. Breakthroughs in science are plenty in the modern era and there is no reason to expect them to slow or halt. However, from your later comments, it sounds as though you feel the only operating definition of a "breakthrough" is a change inducing a rapid rise in labor extraction / conventional productivity. I could not disagree more strongly with this opinio…

That’s only one dimension. The step function is multidimensional. My critique is more about the Euclidean distance between the initial point and the end point.

To which AI is the only technology that has enough distance to be classified as a “breakthrough”.

Re: Is particle physics dead, dying, or just hard?

#330

Here is one fact that seems, to me, pretty convincing that there is another layer underneath what we know. The charge of electrons is -1 and protons +1. It has been experimentally measured out to 12 digits or so to be the same magnitude, just opposite charge. However, there are no theories why this is -- they are simply measured and that is it. It beggars belief that these just happen to be exactly (as far as we can…

The hint from quantum field theory (and things like lattice gauge theory) is that charge emerges from interesting topological states/defects of the underlying field (by "interesting topological shapes" I mean - imagine a vortex in the shape of a ring/doughnut). It's kind of a topological property of a state of the photonic field, if you will - something like a winding number (which has to be an integer). Electric cha…

Is this the same idea behind Williamson & Van der Mark's electron model?

https://www.youtube.com/watch?v=hYyrgDEJLOA

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