Not a physicist or a scientist, but I do follow the news, and I think there's a lot happening 'under the surface' with people working on mathematical foundations (category theory, complexity theory, homotopy type theory) that are going to surface into physics in unexpected ways in the fairly near future.
Ask HN: Is physics moving forward?
31–40 of 75 posts
Re: Ask HN: Is physics moving forward?
#32As someone who's been in physics for much of the last twenty years, I'd guess that things are going at about the same rate. I don't think that the rate is "crawling", though. If you look on log plots of parametrized experimental progress, progress remains linear, so it's a Moore's law like improvement on many fronts. The emergence of precision cosmology has really transformed astrophysics in the last twenty years. Th…
What's EDM?
electric dipole movement or maybe electronic dance music
http://www.int.washington.edu/talks/WorkShops/int_08_3/Peopl...
Re: Ask HN: Is physics moving forward?
#33As someone who's been in physics for much of the last twenty years, I'd guess that things are going at about the same rate. I don't think that the rate is "crawling", though. If you look on log plots of parametrized experimental progress, progress remains linear, so it's a Moore's law like improvement on many fronts. The emergence of precision cosmology has really transformed astrophysics in the last twenty years. Th…
Given your perspective, what do you make of stuff like Umbral Moonshine http://arxiv.org/abs/1204.2779 and ER=EPR http://arxiv.org/abs/1306.0533 ?
Re: Ask HN: Is physics moving forward?
#34I really like these diagrams, as an answer to your question: http://matt.might.net/articles/phd-school-in-pictures/
You can't predict breakthroughs. A scientist might spend their entire career following their research to a dead end. That's not a failure, in my opinion. It just shows how much we already know, and I think we should honour those scientists just as much as the lucky ones.
Re: Ask HN: Is physics moving forward?
#35That depends, how do you quantify progress or rate of progress in physics? To compare directly to technology, Moore's law seems to indicate a accelerating pace of technology. On the other hand looking back to the 90ies progress in computer games, where you could expect a never seen before breakthrough each year, it seems that computers have hit a point of diminishing returns and probably the important metric is something like the log of computing power or something similar. So quantifying rate of progress is not well defined and it seems that it is possible to argue that the rate of progress has slowed down, even for computing power. The counter example would be digital video, where there was very little progress, for the average user, until divX and since the early two thousands, we went from cut scenes at 320x240, to Youtube and 4K video.
Putting the measurement problems aside, progress in physics seems to be a lot less smooth and the big jump occurred in the first three decades of the last century with the discovery of special relativity and quantum mechanics plus the ongoing project of formalizing physics. That one was a complete paradigm shift towards mathematical models and towards an entirely different picture of reality. Since then the development of quantum field theories is basically just using the same trick as for quantum mechanics. ( Not trying to belittle the development of QFT, that is one of the monumental achievements of the human mind, it just pales in comparison to the development of QM. ) So, in this view the next big jump may be just around the corner or not possible for a human brain, but we will only know the answer after progress happened. ( I should cite one of the famous philosophers of science here, unfortunately I forgot which one.)
As an example, string theory is currently not even wrong, because we can not build the known experiments that would enable us to test string theory. However a lot of brain power and ink was expended on its development over the last thirty years, and we simply do not have a good idea if it was worthwhile. If someone suggests a experiment that can distinguish between string theory and other models of quantum gravity, and if a string theory passes this test, then it was probably worthwhile to spend all that effort.
In conclusion, I would argue that the question is ill defined and runs furthermore in epistemological problems, that is even if we would find a good definition we can not really know the answer. However, I am actually quite optimistic that a breakthrough is just around the corner. For example, I think that the connection of information theory and physics is not really understood, but concepts like entropy and information seem to crop up everywhere one looks.
Re: Ask HN: Is physics moving forward?
#36As someone who's been in physics for much of the last twenty years, I'd guess that things are going at about the same rate. I don't think that the rate is "crawling", though. If you look on log plots of parametrized experimental progress, progress remains linear, so it's a Moore's law like improvement on many fronts. The emergence of precision cosmology has really transformed astrophysics in the last twenty years. Th…
In terms of progress on fundamental physics (i.e., ignoring things like material science), this is a very slow crawl on any sensible absolute scale, and certainly vastly slower than progress was made up until the 1970s. With respect, I think you're just renormalizing to the glacial pace we've come to expect.
The Standard Model (including the yet-to-be discovered Higgs and top quark) was completed in the mid '70s around when the bottom and charm quark were found. The pace of discovery of new fundamental particles has clearly slowed dramatically; the top quark was in 1994 and Higgs was just a couple of years ago, with serious pessimism that anything else will come out of the LHC (even with the luminosity upgrades). The existence of an LHC successor is uncertain, and even if it is built it is unlikely to find anything new.
The solar neutrino, compared to just about any other fundamental physics question in the 20th century, is boring. It was solved by adding a few additional free parameters to the SM with little conceptual insight and few implications for further post-SM physics. As you and I commented elsewhere, pentaquarks are a neat window into low-energy QCD, but they aren't new fundamental physics.
Precision cosmology's biggest result was to confirm the ad hoc and simplest inflationary models from the 1980's, with little hope in the near-term future to do anything besides rule out poorly motivated variations designed explicitly to be testable. What is the inflaton like, and what does it do besides adjust a couple of parameters in the CMB? No one knows, and know one has a serious expectation of finding out anytime soon.
None of this, obviously, means that these meager accomplishments weren't hard or that the people who made them aren't extremely clever. But they are undeniably less exciting then what was see before I was born in 1985, and pale in comparison to the absolute revolutions of the first half of the 20th century (quantum mechanics, relativity, GR, field theory).
I really want to call this out:
> huge swaths of parameter space (i.e. possible theories) have been ruled out.
This is the sort of comment that only us physicists can say with a straight face. Parameter space is bounded only by one's cleverness and stamina. Ruling it out says very little about reality because most proposals have very little a priori probability. The entire industry of constructing complicated models and then ruling them out is the lamest kind of progress I can imagine. Perhaps the open questions have really just gotten so hard that this is the best that can be hoped for. But we should be honest that this is essentially like hitting a brick wall and digging into it with spoons.
Re: Ask HN: Is physics moving forward?
#37I just finished a PhD in Transformation Optics and Metamaterials. Metamaterials are a real novel breakthrough in physics which have wide ranging applications for antennas and electromagnetic materials. Not to mention the recent confirmation of the Higgs Boson. Physics is moving along at a similar pace.
Re: Ask HN: Is physics moving forward?
#38It seems to me that ground-breaking discoveries in physics are generally getting more expensive.
Up till about the early 20th century, ground breaking physics was largely "two guys in a garage" territory -- single individuals such as Newton or Cavendish tinkering in their own private laboratories using fairly modest equipment. Teenagers replicate their experiments in school physics lessons with equipment costing no more than a few hundred pounds today.
Throughout the mid-twentieth century, ground-breaking discoveries were increasingly made by teams of researchers, which seem to have grown larger over time, with equipment that has become increasingly large and expensive, and sponsored by universities, companies and governments.
Nowadays it seems that most ground-breaking discoveries are made by large, national or multinational teams working with equipment costing billions of dollars and processing petabytes of data. I couldn't see two guys in a garage producing their own space telescope or particle accelerator any time soon.
Re: Ask HN: Is physics moving forward?
#39I really like these diagrams, as an answer to your question: http://matt.might.net/articles/phd-school-in-pictures/ You can't predict breakthroughs. A scientist might spend their entire career following their research to a dead end. That's not a failure, in my opinion. It just shows how much we already know, and I think we should honour those scientists just as much as the lucky ones.
The trouble with that diagram is that it implies that everything after that initial boundary traversal is a completely new and original contribution to human knowledge. Sadly this is not the case.
Re: Ask HN: Is physics moving forward?
#40As a PhD in physics - progress in pure physics is slowing down (or at least progress per scientist). The delay between a discovery in physics and a Nobel prize is getting bigger and bigger [1]. It's true for all fields, but the effect is particularly strong for physics. '''It is safe to say that late 1920s and early 1930s were the “Golden Age” of 20th century physics, when the progress was lightning-fast and new disc…
Do you think there's a limit on how much we can understand in physics/any field?
My reasoning on this is that since everyone has a finite lifespan, understanding/work will be lost as the researcher retire, move to a different field, or die, unless this information is transmitted to someone else during their life time. However, as we understand more, we have to teach people more. This brings in two problems that I see:
- It takes longer for people to learn up to the frontier of science, which means they might be in their 30s, 40s, and that number may keep getting larger. - We might be able to teach these things in the same amount of time, but the understand of these topics by the younger generation might be less overall, which makes it difficult for them to make certain connections, as they might not have the deep enough understanding to see a connection.
My worry is the eventually we will reach a stage where the amount of knowledge we have is so much that no one can feasibly master a field. We can subdivide the fields, but no one will know enough general knowledge to make insightful connections that simplifies our models, or something to that effect.
As an example: my fluid dynamics professor said that the fluids mechanics I course we take in second year undergrad is what people worked on as their masters/phd thesis 100 years ago, whereas we don't even derive the formulas anymore now simply because we do not have the time to do so.