Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Fundamental physics is dying? [video]

youtube.com

Post reply on HN
Print view View original

121–130 of 245 posts

Re: Fundamental physics is dying? [video]

#121

Post by zachf »

lazide wrote: post #110
farts_mckensy wrote: post #23

Earlier quoted context omitted.

The same could've been said of atomic theory, neutrinos, gravitational waves, the higgs boson, cmb radiation, plate tectonics, and quantum mechanics at various points in time.

No you couldn’t. And it’s been 80 years now!! All of those things you name came directly out of attempts to create testable hypotheses from experimental observations , and all of them were tested as soon as anyone could build an experiment apparatus or gather the data to do it. Which didn’t take that long considering the extreme engineering difficulties in actually building the apparatus for some of them. String theo…

80 years? I would date its birth as 1968-9 (Veneziano), it’s hard for me to imagine calling prior work than that as “string theory”. But never mind that—the bigger problem with this (quite common) argument is that everything about quantum gravity, not just string theory, has avoided testability because our other theories are too good, and because we’re limited to doing experiments on Earth with equipment built on human scales with human budgets, and that’s just not where quantum gravity would naturally make itself known. So really this argument just suggests we shouldn’t study quantum gravity at all. Maybe that’s your actual opinion—it’s a waste of time if we can’t access the Planck scale, we should table it all and sit on our hands until we can. But string theory really is quite interesting to study, stuff like AdS/CFT is just really surprising and magical when you get what it’s about, and it would be a real pity to not pay the meager salaries of theoretical physics just because of pessimism. String theory is so far from fully understood! It’s actually…really hard!

BtW I think you got this 80 years number from looking at the earliest date on the Wikipedia page. You might want to read it more carefully. Not everything leading up to string theory is string theory.

Re: Fundamental physics is dying? [video]

#122

Post by canjobear »

ordu wrote: post #85
ants_everywhere wrote: post #40

My understanding of the situation (which may be wrong, in which case please let me know) is that physics is stuck at a local optimum. There are two obvious ways to get out (1) Surprising physical observations, or (2) Mathematical advances Way (1) is what kicked off quantum mechanics. Way (2) is what kicked off Newtonian mechanics. I see string theorists and loop quantum gravity people as working on (2). Their models…

> physics is stuck at a local optimum. I think I heard somewhere that the trouble with string theory is it can describe anything if you tune it just in a right way. It reminds me of epicycles, they also had this property, you can add more and more epicycles to describe literally any observation data. > Way (1) is what kicked off quantum mechanics. Way (2) is what kicked off Newtonian mechanics. Hmm... What was the wa…

Copernicus used the same circular-orbit-plus-epicycles system as Ptolemy, just the orbits were centered around the sun (kind of---each planet had its own circle, with the sun only approximately in the middle). The system actually had more epicycles than Ptolemy's and was less accurate. It wasn't an advance in any meaningful sense.

The real breakthrough was Kepler, who dropped the idea that planets moved in circles. It was indeed partly a mathematical breakthrough and the reason Kepler's work took a while to catch on is that people couldn't understand his math at first. But it was also empirical, as Kepler had access to new and much more precise observational data collected by his mentor Tycho Brahe.

Re: Fundamental physics is dying? [video]

#123

Post by ahazred8ta »

ordu wrote: post #85
ants_everywhere wrote: post #40

My understanding of the situation (which may be wrong, in which case please let me know) is that physics is stuck at a local optimum. There are two obvious ways to get out (1) Surprising physical observations, or (2) Mathematical advances Way (1) is what kicked off quantum mechanics. Way (2) is what kicked off Newtonian mechanics. I see string theorists and loop quantum gravity people as working on (2). Their models…

> physics is stuck at a local optimum. I think I heard somewhere that the trouble with string theory is it can describe anything if you tune it just in a right way. It reminds me of epicycles, they also had this property, you can add more and more epicycles to describe literally any observation data. > Way (1) is what kicked off quantum mechanics. Way (2) is what kicked off Newtonian mechanics. Hmm... What was the wa…

Before Newton, Kepler already figured out that orbits were ellipses. Newton figured out why orbits are ellipses.

Re: Fundamental physics is dying? [video]

#124

Post by chii »

lamontcg wrote: post #119
jerf wrote: post #60

Earlier quoted context omitted.

Yes, there's definitely some interesting fields that are making progress that are still in the purview of "physics". Materials science, or condensed matter physics, is doing a lot of fascinating work with quasiparticles: https://en.wikipedia.org/wiki/Quasiparticle There's a number of fields you could call "quantum engineering" where physics and engineering work together on the cutting edge. Some of the output of that…

> It's particle physics that seems to be stuck in a rut. You could look at the discovery of tetraquarks and pentaquarks, and high precision tests of the standard model though as a lot of progress. What it hasn't done though is create some sexy upending of our current models of physics, we keep asking questions and mostly the responses coming back are in line with theories that we knew 40 years ago. But that's still a…

> What it hasn't done though is create some sexy upending of our current models of physics

which is fine imho. It's only been around 100 years since that happened last time! Far too short to have another one.

Re: Fundamental physics is dying? [video]

#125

Post by js8 »

hindsightbias wrote: post #111

What if String Theory is a Sophon Virus?

Then it's not really all that well made, frankly, because one of the most popular YT physicists is immune to said virus.

But - I have always dismissed cryptocurrencies thinking "people can't be that stupid". If I had not, I could have made some money. So maybe Sophons didn't expect Youtube to be a thing, either.

Re: Fundamental physics is dying? [video]

#126

Post by rapjr9 »

ManuelKiessling wrote: post #95
rapjr9 wrote: post #86

I have a pet conspiracy theory for why there has been so little progress in physics for so long. The invention of the nuclear bomb scared a lot of people, it made them scared of physics. What else might physicists turn up that could change the world in dramatic ways? Anti-gravity? Ray guns? Other dimensions? Travel to other worlds? All bad for business, no one is going to buy your airplanes or air craft carriers if t…

The theory stops working imho if you take competition into account. The world is not aligned as a single bloc of power. While it’s not completely unthinkable (but extremely unlikely, imho) that some scientists plus some decision makers from, say, the liberal west might collude to achieve this kind of suppression, their counterparts from one or multiple other blocs might not, because they want to dominate and anti-gra…

The desire to dominate can take a weird turn if using your anti-gravity guns reveals them and makes it likely others will soon invent the same. There is precedent for this, say in electronic warfare or cyberwarfare. As soon as you reveal your uber virus, anyone can take it apart and modify it for their own purposes. So you don't reveal it except as a last resort. Competition doesn't come into play then, everyone hides their secret weapons and never uses them unless they have to, and tries to make sure information in that area is suppressed. However, as I say in other comments, this may have been a bottom up conspiracy, not a top down conspiracy, though it may have moved to the top as the scientists themselves gained power. But the fear would still exist at all levels; sure your anti-gravity gun gives you an advantage, but what if it eventually causes random micro black holes to appear near where you use it, obliterating infrastructure before evaporating? We just don't know what the repercussions of new technologies will be, and while the risks have seemed low in areas like software, the risks seem higher with fundamental new physics. People are historically pretty bad at predicting how technology/science will play out in the long term. AI was a joke for a long time, until it wasn't. The internet was hailed as revolutionary, but it seems very different than it did in the year 2000. It's a lot like computer security, you can imagine the possibilities, but you probably can't imagine ALL the possibilities. It takes time and collaboration to scope out what it is that is new that can now be accomplished. That uncertainty scares some people and excites others. Seems kind of like walking through a minefield littered with Christmas presents. Some people might decide to leave the presents where they are.

Re: Fundamental physics is dying? [video]

#127

Post by Ma8ee »

killerstorm wrote: post #93
Ma8ee wrote: post #72

Earlier quoted context omitted.

Those mathematical advances weren't developed in a vacuum, but made to solve some very specific problems which came from better measurements. So even Newtonian mechanics originated in solving problems trying to explain measurements, not that someone sat in their chamber and dreamed up cool math that happened to be very useful.

Number theory and algebraic geometry were developed for their own sake (i.e. "it is cool"), but later people found practical applications in cryptography. So "useful math must be motivated by practice" is empirically false

> So "useful math must be motivated by practice" is empirically false

That was not the claim. The claim is that useful physics originates in measurements.

Re: Fundamental physics is dying? [video]

#128

Post by andsoitis »

btilly wrote: post #67
phkahler wrote: post #61

Earlier quoted context omitted.

>> I've been working on how to formulate that idea clearly for a while. It is a problem that goes well beyond physics. It's a really fundamental thing in psychology. The solution is something like the destruction of the ego, and many people who push hard enough to be a PhD tend toward larger ego to start with. Meditation and practicing martial arts can help. Apparently psychedelics can as well. It's a real pain becau…

The problem is that we need an ego to be healthy. Attempts to destroy it can wind up compromising your mental health. The first part of the solution is to be careful what's in your ego. See https://paulgraham.com/identity.html on this topic. See https://blog.codinghorror.com/the-ten-commandments-of-egoles... for how careful choices in what we value in ourselves, can lead to thinking better. This of course still leave…

> The problem is that we need an ego to be healthy. Attempts to destroy it can wind up compromising your mental health.

You only need to destroy it temporarily. When you do it using certain tools or techniques, it will reconstitute by itself once the effect of the tool or technique has passed.

This temporary ego death can open your eyes without creating a permanent void where your ego used to be.

Re: Fundamental physics is dying? [video]

#129

Post by lazide »

zachf wrote: post #121
lazide wrote: post #110

Earlier quoted context omitted.

No you couldn’t. And it’s been 80 years now!! All of those things you name came directly out of attempts to create testable hypotheses from experimental observations , and all of them were tested as soon as anyone could build an experiment apparatus or gather the data to do it. Which didn’t take that long considering the extreme engineering difficulties in actually building the apparatus for some of them. String theo…

80 years? I would date its birth as 1968-9 (Veneziano), it’s hard for me to imagine calling prior work than that as “string theory”. But never mind that—the bigger problem with this (quite common) argument is that everything about quantum gravity , not just string theory, has avoided testability because our other theories are too good, and because we’re limited to doing experiments on Earth with equipment built on hu…

Fair enough - 50 to almost 60, not counting s-field precursor work.

I’m not saying string theory isn’t potentially interesting from a mathematics perspective, I’m just saying treating it like physics (which is, explicitly about testable/falsifiable theories) is BS.

If we were honest about it, it would be a maths speciality eh?

At least until there are more clear attempts at making testable hypotheses.

But that would cause other issues with funding I imagine.

If quantum loop gravity comes up with a testable hypotheses, then hey, maybe I’m wrong. But so far, not so much yeah? And I’m not talking ‘we’d need to spend a lot of money to test it’, I mean an actual testable/falsifiable hypotheses at all.

Re: Fundamental physics is dying? [video]

#130

Post by randomNumber7 »

XorNot wrote: post #105
jerf wrote: post #60

Earlier quoted context omitted.

Yes, there's definitely some interesting fields that are making progress that are still in the purview of "physics". Materials science, or condensed matter physics, is doing a lot of fascinating work with quasiparticles: https://en.wikipedia.org/wiki/Quasiparticle There's a number of fields you could call "quantum engineering" where physics and engineering work together on the cutting edge. Some of the output of that…

> Since people on the internet frequently seem to operate on the silly theory that someone pointing out a problem has some sort of obligation to propose a solution The issue with Sabine is she tends to yell about anyone proposing any solution. CERN would like to build a bigger particle accelerator, but since it's not her favored variant of accelerator they are obviously lying to the public and wasting your tax payer…

She has reasonable arguments that the money could be invested into more promising research.

It's ok you don't agree, but your only argument is to attack her personally. Smells like you are personally invested.

Post reply on HN