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Is particle physics dead, dying, or just hard?

quantamagazine.org

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

#161

Post by indymike »

raincole wrote: post #153
benreesman wrote: post #141

It is almost always the case that when progress stops for some meaningful period of time that a parochial taboo would need violating to move forwards. The best known example is the pre- and post-Copernican conceptions of our relationship to the sun. But long before and ever since: if you show me physics with its wheels slipping in mud I'll show you a culture not yet ready for a new frame. We are so very attached to t…

It's easy to give up existing concepts. It's called being a crackpot and you can find thousands of papers doing that online.

I'm not sure the crackpot is what we're talking about here. We're talking about something tht violates the prevailing opinion in a way that can be verified, and results a change in what we know to be true. The crackpot is mostly the result of a very aspirational world view, and usually under the hood has bias and error that is often quite obvious.

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

#162

Post by gary_0 »

jacquesm wrote: post #134
tariky wrote: post #115

To my uneducated eye it looks like they are stuck in limbo for 120 years. Nothing practical has been create based on those theories. It is just words and calculations spinning in circles. I wish those people focus on practical real world physics. So we all can enjoy new innovations.

> Nothing practical has been create based on those theories. Ever used GPS? A CD player? A laser? Semiconductors?

Einstein laid the theoretical foundations for lasers in 1917, and it took over 40 years of "impractical" scientific work before the first functioning laser was built. It took decades more for them to become a cheap, ubiquitous technological building-block. The research is still continuing, and there's no reason to assume it will stop eventually bearing fruit (for the societies that haven't decimated their scientific workforce, anyways). Look at the insanity required to design and build the EUV lasers in ASML's machines, which were used to fabricate the CPU I'm using right now, over a century after Einstein first scribbled down those obscure equations!

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

#163

Post by dgfl »

jacquesm wrote: post #124
galaxyLogic wrote: post #112

Earlier quoted context omitted.

I don't think there is any mystery to what we call "consciousness". Our senses and brain have evolved so we can "sense" the external world, so we can live in it and react to it. So why couldn''t we also sense what is happening inside our brains? Our brain needs to sense our "inner talk" so we can let it guide our decision-making and actions. If we couldn't remember sentences, we couldn't remember "facts" and would be…

This is not nearly as profound as you make it out to be: a computer program also doesn't sense the hardware that it runs on, from its point of view it is invisible until it is made explicit: peripherals.

You also don’t consciously use your senses until you actively think about them. Same as “you are now aware of your breathing”. Sudden changes in a sensation may trigger them to be conscious without “you” taking action, but that’s not so different. You’re still directing your attention to something that’s always been there.

I agree with the poster (and Daniel Dennet and others) that there isn’t anything that needs explaining. It’s just a question framing problem, much like the measurement problem in quantum mechanics.

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

#164

Post by krzat »

libraryofbabel wrote: post #40
rjh29 wrote: post #22

Earlier quoted context omitted.

One argument (while unsatisfying) is there are trillions of possible configurations, but ours is the one that happened to work which is why we're here to observe it. Changing any of them even a little bit would result in an empty universe.

There’s a name for that: the Anthropic principle. And it is deeply unsatisfying as an explanation. And does it even apply here? If the charge on the electron differed from the charge on the proton at just the 12th decimal place, would that actually prevent complex life from forming. Citation needed for that one. I agree with OP. The unexplained symmetry points to a deeper level.

I find the anthropic principle fascinating.

I was born to this world at a certain point in time. I look around, and I see environment compatible with me: air, water, food, gravity, time, space. How deep does this go? Why I am not an ant or bacteria?

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

#165

Post by dgfl »

tehjoker wrote: post #119
galaxyLogic wrote: post #112

Earlier quoted context omitted.

I don't think there is any mystery to what we call "consciousness". Our senses and brain have evolved so we can "sense" the external world, so we can live in it and react to it. So why couldn''t we also sense what is happening inside our brains? Our brain needs to sense our "inner talk" so we can let it guide our decision-making and actions. If we couldn't remember sentences, we couldn't remember "facts" and would be…

another one that thinks they solved the hard problem of consciousness by addressing the easy problem. how on earth does a feedback system cause matter to "wake up"? we are making lots of progress on the easy problem though

This is not as good a refusal as you think it is. To me (and I imagine, the parent poster) there is no extra logical step needed. The problem IS solved in this sense.

If it’s completely impossible to even imagine what the answer to a question is, as is the case here, it’s probably the wrong question to pose. Is there any answer you’d be satisfied by?

To me the hard problem is more or less akin to looking for the true boundaries of a cloud: a seemingly valid quest, but one that can’t really be answered in a satisfactory sense, because it’s not the right one to pose to make sense of clouds.

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

#166

Post by gary_0 »

benreesman wrote: post #141

It is almost always the case that when progress stops for some meaningful period of time that a parochial taboo would need violating to move forwards. The best known example is the pre- and post-Copernican conceptions of our relationship to the sun. But long before and ever since: if you show me physics with its wheels slipping in mud I'll show you a culture not yet ready for a new frame. We are so very attached to t…

I'm pretty sure quantum mechanics already forgoes conventional causality. Attosecond interactions take place in such narrow slices of time that the uncertainty principle turns everything into a blur where events can't be described linearly. In other words, the math sometimes requires that effect precedes cause. As far as we can tell, causality and conservation of energy is only preserved on a macroscopic scale. (IANAQP, but I'm going off my recollections of books by people who are.)

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

#167

Post by sigmoid10 »

sashank_1509 wrote: post #158
mattlangston wrote: post #71

Experimental particle physicist here. It's just hard. I measured the electron's vector coupling to the Z boson at SLAC in the late 1990s, and the answer from that measurement is: we don't know yet - and that's the point. Thirty years later, the discrepancy between my experiment and LEP's hasn't been resolved. It might be nothing. It might be the first whisper of dark matter or a new force. And the only way to find ou…

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 extreme precision and in a much more economical way to study particle physics. Heck, commercial MRIs exist and continue to improve because physicists want cheaper, stronger magnets so they can build more powerful colliders. What if in the future you could do advanced screening quickly and without hassle at your GP's office instead of having to wait for an appointment (and possibly pay lots of money) at an imaging specialist center? And if they find something they could immediately nuke it without cutting you open? We're talking about the ultimate possibility of Star Trek level medbays here.

Let the physicists build the damn thing however they want and future society will be better off for sure. God knows what else they will figure out along the way, but it will definitely be better for the world than sinking another trillion dollars on wars in the middle east.

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

#168

Post by suddenlybananas »

XorNot wrote: post #25
Paracompact wrote: post #23

Earlier quoted context omitted.

What about underexplained cosmological epicycles like dark matter (in explaining long-standing divergences of gravitational theory from observation), or the Hubble tension?

This is your regular reminder that epicycles were not an incorrect theory addition until an alternative hypothesis could explain the same behavior without requiring them.

Scientific theories are not curve-fitting.

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

#169

Post by quchen »

andyferris wrote: post #114
tasty_freeze wrote: post #15

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…

(Note the post you’ve replied to mentioned electrons and _protons_, not positrons.)

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

#170

Post by tsimionescu »

throw_m239339 wrote: post #31
bananaflag wrote: post #7

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.

I find the idea that reality might be quantized fascinating, so that all information that exists could be stored in a storage medium big enough. It's also kind of interesting how causality allegedly has a speed limit and it's rather slow all things considered. Anyway, in 150 years we absolutely came a long way, we'll figure it that out eventually, but as always, figuring it out might lead even bigger questions and my…

Note that "reality" is not quantized in any existing theory. Even in QM/QFT, only certain properties are quantized, such as mass or charge. Others, like position or time, are very much not quantized - the distance between two objects can very well be 2.5pi planck lengths. And not only are they not quantized, the math of these theories does not work if you try to discretize space or time or other properties.
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