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Has Physics Gotten Something Really Important Really Wrong?

346 points by danielam 10y ago

rwmj 10y ago
That's nice. Have any falsifiable claims been made?
- RivieraKid 10y ago
  Some claims don't have to be falsifiable to be true. For example, some people say that solipsism is not falsifiable - I don't see what's wrong with that.
- sgt101 10y ago
  That if theoretical physics goes on the way that it is the funding for it will fall to 0 within 50 years?
jaggederest 10y ago
So as per usual with headlines in the form of a question, the answer from the article appears to be no. It might be more accurate to title it "Physicist and Philosopher question the empirical underpinnings of physics". There's not really anything here to disprove anything from the current standard models.
- johncolanduoni 10y ago
  Also most of the rest of physics has been chugging along pretty well. People that are working on this particular problem from any angle (string theory or any other attempts at unification) are a minority in the physics community. If the title was theoretical high energy physics was in a crisis, I'd be more inclined to agree.
- iaw 10y ago
  The word "empirical" implies that there's some evidence to back up the claims in the work on string theory and the multiverse. A more apt summary may be "Physicist and Philosopher point out lack of empirical underpinnings for esoteric branches of physics"
- alexandercrohde 10y ago
  Agreed. I'm really unclear on what is is supposed to be new about this post. As far as I know, it's considered that multiverse is highly-theoretical (potentially non-falsifiable). String theory, a dozen dimensions, etc are still speculative and treated as unproven. Nobody said any of that was proven.
Xcelerate 10y ago
I don't think the problem is string theory per se — I think the problem is that we're running up on the bounds of what we can test experimentally, and further progress is going to require some really cleverly designed experiments that can probe Planck scale events. Although the greatest physicists throughout history have for the most part been theoreticians, it may be the case that in the future, the greatest physicists will be experimentalists because of the extraordinary amount of creativity needed to design novel experiments that can probe the most obscure corners of reality. String theory isn't pseudoscience, because it does make testable, falsifiable predictions. In fact, it makes the same predictions that quantum field theory does for the phenomena that we are currently capable of testing (and arguably using a more elegant framework than QFT provides). The problem is that the predictions that string theory makes beyond QFT are currently way outside the realm of experimental assessment. This doesn't make the predictions false — if that's the way the universe really is, we just may be incapable of knowing that for a long time. There are a few hints that at least some of the predictions of string theory may be incorrect — we have yet to find any evidence of supersymmetry, and many physicists thought the LHC would turn up at least some evidence of this if it existed. Regardless, I think people get too hung up on buzz-phrases like "is time real?" or "are we in a multiverse?". A lot of these are what I consider irrelevant to science, as the goal of science is to make accurate predictions about the future. If there is another universe out there, it is by definition unreachable from our current universe, so it makes no difference to science whatsoever. Likewise, what is or isn't "real" has no bearing on how accurately one can compute the evolution of some system's state through time.
- nol13 10y ago
  But how can you make accurate predictions about the future if time isn't real? Chew on that science boy.
  - wolfgke 10y ago
    Even if time emerges from something different it is still there.
    - 10y ago
therestisgone 10y ago
Clickbait of the year. Yessss, keep feeding me more of those delicious downvotes.
- dang 10y ago
  We've banned this account for violating the HN guidelines.
Animats 10y ago
This is Smolin, making his usual, and valid, criticisms of modern physics. Smolin's basic complaint is that there is no experimental evidence for string theory. The math is pretty, and a whole generation of physicists have worked on it, but nothing is experimentally testable. Everything is too small or at too high an energy level. A practical implication is that it doesn't lead to any technology. Smolin also doesn't like many-worlds, because it talks about unreachable regions. This he considers too speculative. There's a basic problem in quantum mechanics, which leads to Schroedinger's Cat, the Copenhagen Interpretation, and, in the end, many-worlds.[1] Physics has been stuck on this problem for almost a century now. Philosophy won't help. [1] https://en.wikipedia.org/wiki/Copenhagen_interpretation https://en.wikipedia.org/wiki/Copenhagen_interpretation
- dmfdmf 10y ago
  > Physics has been stuck on this problem for almost a century now. Philosophy won't help. It sure seems to be an epistemology problem which puts it squarely in the realm of philosophy, not physics.
  - xyzzyz 10y ago
    Maybe, but sadly philosophy doesn't have a good track record when it comes to actually solving problems.
    - ohyes 10y ago
      Bullshit. How do you think your computer functions? You don't get high level programming languages without philosophy. Where do you think natural sciences came from?
      - Numberwang 10y ago
        I think of philosophers as basically being 1000 Shakespearean monkeys. The world would be better served by 1000 scientists.
mstank 10y ago
As a layman, one thing I don't understand is why we suppose there has to be dark matter and energy in the universe. I understand that dark matter is used to explain gravitational irregularities when observing galaxies. However, saying 'there is x amount of unobservable stuff there' in order to make our calculations correct seems like lazy science. Are there any theories that don't include dark matter or energy? Can gravity function differently depending on its location (space or time) in the universe?
- empath75 10y ago
  https://en.wikipedia.org/wiki/Dark_matter#Alternative_theories https://en.wikipedia.org/wiki/Dark_matter#Alternative_theori... Yes. Hardly anyone takes them seriously, though, for a variety of reasons.
- Manishearth 10y ago
  > However, saying 'there is x amount of unobservable stuff there' in order to make our calculations correct seems like lazy science. That's not how this works. Dark matter and energy are placeholders for anything that can explain the discrepancy. The most likely explanation for dark matter is just undiscovered particles, but changing the physics of it to make the calculations come out right is also something that people do. There's not really a difference between the two either. Post-QFT the concept of a particle is much blurrier than before, and "changing the physics" might just involve introducing a new background field that behaves differently in different places based on its concentration. In essence, you have introduced a new particle. Please note that while it feels like lazy science, coming up with alternate theories that have the same success and rigor as QFT is very hard. Its not that they are hanging up their pencils and declaring premature victory. It is that literally the best description of physics out there to date doesn't explain this, and within that description yet-to-be-observed particles is its best bet. They are working on better explanations, but Rome wasn't built in a day.
  - teamonkey 10y ago
    Here's an interesting theory. https://astronomynow.com/2016/06/16/did-gravitational-wave-detector-find-dark-matter/ https://astronomynow.com/2016/06/16/did-gravitational-wave-d... The gravitational waves we're detecting come from black holes, but the readings we have from LIGO suggest that they most likely come from 'primordial' black holes formed at the birth of the universe. If many of these black holes were formed they would be distributed much as MACHO theory predicts. 'Normal' black holes have very specific mass profiles so were generally ruled out as MACHOs, although obviously 'dark matter = black holes' has had a lot of consideration.
lolc 10y ago
I like how they see cosmologists as historians. Observe and describe the past, speculate, and muse about the future :-)
HillaryBriss 10y ago
> ... reification of mathematics can lead physicists into dangerous territory where mathematical "beauty" and "elegance" get substituted for real information about the real world. If it can happen in physics, it can happen anywhere -- maybe even your neighborhood.
vortico 10y ago
This was a pretty useless article with no real information or details to counter existing theories. I know the layman usually isn't interested in the details, but you can't just write about nothing. Are there consistent theories with those three features? What are features of existing models of cosmology which will have to be changed if the three features are assumed? The reader will never know.
empath75 10y ago
That we aren't capable of experiments that distinguish between various forms of string theories doesn't negate the fact that string theories are already compatible with all the experiments we've already done and are likely to be done in the near future. This is no small achievement. There is no other framework that is even in contention right now. Perhaps when we have some alternative theory that survives that basic hurdle, we can discuss whether we're wasting time pursuing string theory rather than some other idea.
- Xcelerate 10y ago
  > string theories are already compatible with all the experiments we've already done and are likely to be done in the near future Yeah, not enough people are aware of this in my opinion.
- vacri 10y ago
  > string theories are already compatible with all the experiments we've already done and are likely to be done in the near future So is the theory "A god did it".
- jcranmer 10y ago
  Supersymmetry is one (although it's not really a competitor to string theory, more an orthogonal theory). One of the complaints on string theory, as I understand it, is that it ends up being too general: it sort of implies that just about any phenomenon could be plausible, which makes it really hard to falsify. It's not so much that it's made predictions that turned out to be true, but rather that it can be accommodated to fit prior experiments. From a Bayesian perspective, we haven't received any evidence of its truth, only evidence of nontruth of other theories.
  - auntienomen 10y ago
    This is a complaint rooted in sociology. People thought back in the 80s & 90s that string theory might be so constrained that can only describe one universe (presumably ours). They were wrong. String theory's more constrained than quantum field theory, but it's still capable of describing a lot of different universes. Most of the people who study it at the moment study it because it's been a fruitful source of ideas about quantum field theory. These people don't give press interviews very often, though.
jwatte 10y ago
You know what's cool? If they can reach better prediction, faster, with that approach, it will strengthen. If they can't, they will be a footnote. At least, if the scientific method is alive and well.
- Manishearth 10y ago
  The scientific method has been "on hold" in theoretical physics for a while; because our experimental technology just can't cope up with it. This is one of the main criticisms of string theory, for example.
mbfg 10y ago
> There is only one universe ok, except what else just has 1 of them > Time is real ask a photon that
- Manishearth 10y ago
  The whole "time is real" part of the article read like meaningless drivel to me. I have no idea what they were trying to communicate.
  - mindcrime 10y ago
    As far as that goes, we arguably don't even know what time is.
    - Manishearth 10y ago
      That can be said of just about anything in physics.
      - mindcrime 10y ago
        Good point!
  - sgt101 10y ago
    That the block universe model is just that : a model which is useful for solving problems, not a description of reality. This is a big problem for physics; confusing the modelling for truthiness. If you go for it all the way eventually you end up in a room with very, very think wallpaper engaging Max Telmark in a shouted conversation. This is part of the maths as selectively reflective of reality conversation.
    - Manishearth 10y ago
      > This is a big problem for physics; confusing the modelling for truthiness I'm pretty sure it isn't ; ever since quantum mechanics physicists have been very good at separating the two. Popsci, not so much, but the actual physics is very clear about it being a model.
deleted 10y ago
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RivieraKid 10y ago
I'm quite surprised that there's not a consensus about the philosophical framing of physics (metaphysics). The way I see it: - Consciousness (perceptions, feelings, thought) is the only thing that really exists. - There are patterns in what we perceive, for example, when we drop a rock, we see it falls and hear the impact. - So we develop models to describe patterns in our consciousness. Physics is just a description of those patterns. So the physical world doesn't really exist, it's just an idea in our minds.
- ffwd 10y ago
  The problem is this is self evident and doesn't explain anything. Saying that consciousness is the only thing that exists is like saying God created the universe. Well then who created God? We have to try to explain what all this is through our conscious experience, and if it happens to be that it's impossible for us to do so, we'll have to re-evaluate our options then. I personally don't believe this to be the case - I think everything exists and consciousness is only one way too perceive that everything, but that's another debate I guess
  - RivieraKid 10y ago
    > The problem is this is self evident and doesn't explain anything. Definitely not self evident, vast majority of people don't see things this way. It doesn't have to explain anything, it's something akin to observation. Just a description of how things are, not an explanation. > Saying that consciousness is the only thing that exists is like saying God created the universe. I don't get this, how is this remotely similar, what does God have to do with this? The way I see it, history is just mental concept / idea. We take our physical model and similate the current state of the universe backwards - and call this history. > I personally don't believe this to be the case - I think everything exists and consciousness is only one way too perceive that everything, but that's another debate I guess Well, you only have perceptions (what you see, hear, feel, ...). It's the only thing you can be sure of. The "real world" is in its essence a thought, idea, mental model. Think about what does the statement "Eiffel tower exists" mean. It's a probabilistic statement about future perceptions - if you go to Paris, you will probably see it.
ianbicking 10y ago
If you disregard aesthetics, what are the questions we're trying to answer in physics, particularly those that involve observable phenomena? I get that string theory replicates the predictions of the theories that preceded it, the critique I'd infer is that it doesn't offer any practical advantages over the previous theories, it doesn't predict anything new that we can observe, and it does not make any problems more tractable (I think the opposite? Ie most problems are far more intractable using string theory) It seems like there's some lack of imagination here, like physics is "done", there's nothing more to answer, it's all just up to other sciences to answer the rest of the (many) questions about why the world is what it is and how it works. A reset of approaches is interesting, but it still needs to be in service of something, doesn't it?
- burke 10y ago
  > what are the questions we're trying to answer in physics, particularly those that involve observable phenomena? (disclaimer: I am not a physicist, etc.) Between GR and QM, we can explain most observable phenomena, but it's intuitively obvious that both are emergent properties of some deeper law. I don't suspect frontier physics is ever really studied with an eye to application. Those tend to follow, but the bleeding edge of physics is usually advanced just out of intellectual curiosity, to try to understand the universe. In this sense, String Theory is just an attempt the unify General Relativity with Quantum Mechanics. The fact that it's not apparently testable is unfortunate, We can have pedantic arguments about whether that's "Real Science", since science by definition requires testable hypotheses, but at the end of the day, I don't think it's crazy to pursue a model to encompass QM and GR, even if it can't be called "Science".
  - ianbicking 10y ago
    > I don't suspect frontier physics is ever really studied with an eye to application. Previously they did have experimental results they were trying to understand. There might be follow up experiments to confirm, but there were already experimental tensions. > I don't think it's crazy to pursue a model to encompass QM and GR, even if it can't be called "Science". I'm not so concerned about whether something is science, it just seems like vanity to pursue unification that provides no insight into the complex world around us.
tamana 10y ago
NPR is not immune to betteridge's. Physics isn't "wrong" about string theory. String theory is a currently untestable theory, a mathematical model, and that's fine but minimally useful.
lossolo 10y ago
Hm i wonder why someone thought there is some invisible, unobservable dark matter instead connecting gravitational waves with super massive black holes in center of every galactic. It seems for me like a lot better answer to question what is keeping galaxies together if observable mass is not enough.
- goodcanadian 10y ago
  I found it a bit hard to understand before I actually took the course in university, but I'll try to explain simply: You can infer the mass that is interior to an orbit by measuring the speed at which an object is orbiting. By measuring the redshift and blueshift, we can get speeds of different parts of the galaxy. It turns out that we can account for more-or-less all of the mass near the centre of galaxies, but as we get further out, orbital velocities seem to be higher than they should be implying more mass is there than we can actually see. In other words, we can tell that the missing mass is not at the centre of the galaxy, but rather spread throughout it.
  - lossolo 10y ago
    I see, it makes sense now, thank you for very clear explanation.
dc2 10y ago
I very proudly have not clicked the link, because it so such wild click bait, that it would be against my integrity.
joslin01 10y ago
Genuine confusion here -- how can you assert time is real? From my limited understanding, time is merely the measurement of change. A comet goes from point A to B, and like a screen flickering, it is in a discrete point in space every step along the way. It is time that is introduced when asking ourselves, "how long did it take?" or "when was it at X?" but how can it be woven into the fabric of the universe? If we take reality to be right here, right now, it doesn't seem to exist but rather is a human invention to help us map change.
- Koshkin 10y ago
  Thing to understand is that time is not a measurement, time is what we measure - as a phenomenon that has independent existence as part of the physical reality. More accurately (and perhaps more confusingly), time should be thought of as one of the aspects (components) of the 4-dimensional "spacetime", where spatial dimensions are, in fact, inseparable from the temporal dimension - so that the results of measurements of each component individually end up being dependent on the frame of reference.
perseusprime11 10y ago
This is like Fermat's last theorem. A whole lot of smart mathematicians spent their time solving this theorem instead of finding better things to solve that can benefit humanity.
auggierose 10y ago
They should take their own medicine. How would one test those three assumptions they make? As for Mathematics being selectively real, I agree with that totally. Mathematics is just a language we use to describe models and their properties in a most rigorous way. That's all. Can we find a model of the universe from which we can derive all its properties? Unlikely (see Gödel), if so the model would have to be pretty "primitive" and thus too large for comprehension. But so what, we can find great models for certain aspects of reality, and I don't see a limit for how far this can be taken to get better and better models for more and more areas of reality.
davesque 10y ago
To me, it's all a matter of the empirical data and the math that attempts to model that data. Those two sides of science have continually bootstrapped each other to the point we've arrived at today. Quoted from the book in the article: "Our mathematical inventions offer us no shortcut to timeless truth... They never replace the work of scientific discovery and of imagination. The effectiveness of mathematics in natural science is reasonable because it is limited and relative." I'm not sure what the authors mean by this. Are we to ultimately abandon our attempts at a consistent, logical explanation of what we see? If so, that's when we revert to un-scientific and, essentially, religious ways of thinking. I'd argue that the pursuit of a mathematical explanation of observations is the work of scientific imagination. Mathematics is merely the most reliable way we've devised of communicating what we imagine to other people. And sometimes the math, itself, sings to you and that drives advances in understanding that are totally valid.
- eli_gottlieb 10y ago
  Smolin wrote a paper on the "reasonable effectiveness" of mathematics in science. http://arxiv.org/pdf/1506.03733v1.pdf http://arxiv.org/pdf/1506.03733v1.pdf
  - davesque 10y ago
    Thanks for this. Very interesting.
tvural 10y ago
Shallow criticisms of string theory usually miss how difficult it is to come up with physical theories that don't lead to some kind of contradiction. For this reason, lots of new physics has been discovered by looking at mathematical constraints first and experiments second. The math of string theory is pretty, but more importantly it works out, and this alone makes string theory worthy of some attention. If it's getting too much attention, that's probably more a sign that there are very few interesting research directions left in physics than that all the physicists are deluding themselves.
sova 10y ago
define event
dschiptsov 10y ago
Yes, by producing disconnected from reality abstractions.
andrewflnr 10y ago
"We're tired of the un-proven assumptions underlying modern physics. Here's some un-proven assumptions to get us back on track." What? How is this helping?
jnefbebyby 10y ago
I read this book a couple of years ago. About 1/3 (Smolin's) of it is really interesting. The main point about the primacy of Time is that traditional models of physics have an implicit time dimension for the laws, in additional the the time dimension of spacetime. Smolin suggests that the the laws of Physics are dynamical, evolving as a function of the state of the system.
erikb 10y ago
And yet, that's all the point of theoretical science. To think in ways even if they are not provable at this time. And then experimental scientists come along, look at the theories and then think about how to experiment on them. That's how it works. And I think if they want to disprove any of this they need to show that this system is broken. I need to google but I'm sure everybody can remember hearing a few times in their life that there were scientists like Einstein who had ideas that could not be proven in their life time but could be proven now with modern computers and now we know they were true. We admire that and we need that. And that's the thesis they need to fight if they want to convince me of theoretical science being wrong or bad.
- dschiptsov 10y ago
  Nope. The point of science is to follow scientific method, which is, contrary to the popular opinion, not about piling up meaningless abstractions cemented by dogmas and wishful thinking, but throwing every possible objection to the hypothesis, finding controversions and inconsistencies with other aspects of reality, and only when it stands nevertheless, that hypothesis could be accepted as a current approximation to the truth. This "science" is as bad pile of nonsense as Hegelian "philosophy".
andrewclunn 10y ago
Was expecting pseudo science based on the click-baity title. Instead got a take down of the pseudo science infecting cosmology. Nice.
abpavel 10y ago
In other news: 1. Time Gravitates! Physicists discover stable wormhole configuration by accounting the effect of gravity on time! and then 2. First wormhole to another universe successfully created! The final experimental proof of multiverse theory, which grants us access to all 10^500 universes, and any place in our own corner of the world" and then 3. Now in portable format, just for $299! Stop being impatient!
DrNuke 10y ago
Problem with philosophy is that it views all anthropocentric. On the other hand, we are beyond anthropocentrism in modern physics in the sense that sensorial / bodily experience (our way to interact with the outer world) doesn't help any more and thinking / mind abstraction (our special way to represent the outer world) is unprovable because technologies and tools are not there yet. More than philosophy, it is literature to stand up when we need a change of paradigm, in particular science fiction: minds trying to carve skewed views of the universe starting from non-mainstream philosophy. Suffice to say, it will be many more misses than hits but gold is there.
- spacehome 10y ago
  I didn't understand any of that.
  - DrNuke 10y ago
    It's literature before philosophy and physics.
nsuser 10y ago
Nice clickbait title..
tim333 10y ago
While I agree with Smolin that much physics has moved away from experimental observation, especially string theory, I think the three numbered points in the article are wrong. My take - the only way the universe could have got here from nothing as it were is if it's basically maths and seems real to us. I mean what does basic particle behavior look like - a bunch of maths and not much else, and what exist without needing creating - mathematical patterns and relations and nothing else. Hence from observation it's probably all maths. Hence: 1) There is only one universe. - Nah probably all mathematically possible universes seem real to their occupants. 2) Time is real. - Sorta but more like how time exists in a DVD of a movie. Or as some guy wrote "...for us physicists believe the separation between past, present, and future is only an illusion, although a convincing one." 3) Mathematics is selectively real. - Nah it's real.
deleted 10y ago
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jokoon 10y ago
Logical and structured thinking is good tool when doing physics, because a precise model can be used as a language and communicated and taught, since it's simple. But those models are correct only in what they describe, they don't completely describe nature. They are just that, models. Every time science has progressed, it's either an "exception to the rule", or a re-understanding of an incomplete theory. I'm not a scientist, but I vividly remember how a physics professor warned us about the laws he was teaching. Those laws work well, use them, but never pretend that they're universal and that they will be for the next 20 or 100 years. You can see this problem in quantum mechanics. Quantum mechanics is being very hard on philosophy and certainty in general. Up to a point, using models might be a limit to physics.
- cmplxconjugate 10y ago
  I am a physicist and one thing that you realise, as you develop as a scientist, is the fact that the perception that "physics describes everything perfectly" is not true. When you start out, lets say as an undergraduate, you feel the pressure to be "correct". You struggle to find the correct answers or construct them. The breakthrough comes when you realise that we use mathematics as a tool to extract answers; we do our best to make the best educated guess we can and interpret the results. A great example would be with something like density functional theory (DFT), where we make extremely crude approximations for exchange and correlation functionals. By understanding the limits of our model we can use this information to improve the results; as Feynman said: "The first job of a theoretical physicist is to prove yourself wrong as fast as possible". I'm not sure I agree with your last statement: >Up to a point, using models might be a limit to physics. I argue that this is the most important thing to physics. The moment you start to leave a model, you allow for subjective speculation. I argue that this has no place in physics and is the prime reason that physics has broken away from philosophy.
  - jokoon 10y ago
    > you allow for subjective speculation Don't you need to speculate at one moment or another to improves physics? Of course you can only do that once you studied physics a lot, but if you want to be creative in physics, don't you have to "speculate" that work with the data?
williesleg 10y ago
Scientists are wrong to believe all that exists can be perceived by our senses, or envisioned in our minds. We are a small minute subset of what is out there. A pimple on the ass of the universe.
garyclarke27 10y ago
I agree with much of the sentiment such as string theory and multi universes are nonsense. Yes math is just an abstraction tool, with mutually understood/ agreed rules , the rules and representations are not exactly true in the real world, users just agree them to assist with communication between users and over time. Time is Not Real, it's an abstraction / quantification of change, but yes change is I think real i.e. the universe is always changing. However his statement- Our ability to map out the history of the universe back to a fraction of an instant after its inception is a triumph - ruined it for me - an absurd statement for a scientist - we have no idea how the universe started we are only guessing it's history, the big bang theory is just a theory, probably no more real than Lord of the Rings.
- Tyr42 10y ago
  Sounds like you haven't seen much of the evidence for big bang theory. I'm going to call your attention to the COBE mission. http://science.nasa.gov/missions/cobe/ http://science.nasa.gov/missions/cobe/ This took the predictions from the big bang theory about a small hot dense universe, and measured the cosmic background radiation, and it matched perfectly. The idea is that when the universe was young, it was so hot that all the matter was in a plasma cloud, and that photons (and other EM radiation) couldn't travel very far at all before being absorbed and re-emitted in a random direction. Then, the universe expanded and cooled enough that the cloud became transparent. But there were still those photons (etc) that now just kept going in all directions. Some of them happen to be arriving from all directions no matter where you are (unless you're on the rim of the universe or something). That's the cosmic background radiation. And we measured it, and it matched so well with the predicted numbers it was astounding. This is also the graph that shows up on the "Science, it works bitches!" xkcd shirt. https://www.explainxkcd.com/wiki/index.php/54:_Science https://www.explainxkcd.com/wiki/index.php/54:_Science
peterburkimsher 10y ago
Betteridge's law of headlines: "Any headline that ends in a question mark can be answered by the word no." Has the Hacker News upvote system gotten something really important really wrong?

346 points by danielam 10y ago

rwmj 10y ago

That's nice. Have any falsifiable claims been made?

RivieraKid 10y ago
Some claims don't have to be falsifiable to be true. For example, some people say that solipsism is not falsifiable - I don't see what's wrong with that.
sgt101 10y ago
That if theoretical physics goes on the way that it is the funding for it will fall to 0 within 50 years?

jaggederest 10y ago

So as per usual with headlines in the form of a question, the answer from the article appears to be no. It might be more accurate to title it "Physicist and Philosopher question the empirical underpinnings of physics". There's not really anything here to disprove anything from the current standard models.

johncolanduoni 10y ago
Also most of the rest of physics has been chugging along pretty well. People that are working on this particular problem from any angle (string theory or any other attempts at unification) are a minority in the physics community. If the title was theoretical high energy physics was in a crisis, I'd be more inclined to agree.
iaw 10y ago
The word "empirical" implies that there's some evidence to back up the claims in the work on string theory and the multiverse. A more apt summary may be "Physicist and Philosopher point out lack of empirical underpinnings for esoteric branches of physics"
alexandercrohde 10y ago
Agreed. I'm really unclear on what is is supposed to be new about this post. As far as I know, it's considered that multiverse is highly-theoretical (potentially non-falsifiable). String theory, a dozen dimensions, etc are still speculative and treated as unproven. Nobody said any of that was proven.

Xcelerate 10y ago

I don't think the problem is string theory per se — I think the problem is that we're running up on the bounds of what we can test experimentally, and further progress is going to require some really cleverly designed experiments that can probe Planck scale events. Although the greatest physicists throughout history have for the most part been theoreticians, it may be the case that in the future, the greatest physicists will be experimentalists because of the extraordinary amount of creativity needed to design novel experiments that can probe the most obscure corners of reality. String theory isn't pseudoscience, because it does make testable, falsifiable predictions. In fact, it makes the same predictions that quantum field theory does for the phenomena that we are currently capable of testing (and arguably using a more elegant framework than QFT provides). The problem is that the predictions that string theory makes beyond QFT are currently way outside the realm of experimental assessment. This doesn't make the predictions false — if that's the way the universe really is, we just may be incapable of knowing that for a long time. There are a few hints that at least some of the predictions of string theory may be incorrect — we have yet to find any evidence of supersymmetry, and many physicists thought the LHC would turn up at least some evidence of this if it existed. Regardless, I think people get too hung up on buzz-phrases like "is time real?" or "are we in a multiverse?". A lot of these are what I consider irrelevant to science, as the goal of science is to make accurate predictions about the future. If there is another universe out there, it is by definition unreachable from our current universe, so it makes no difference to science whatsoever. Likewise, what is or isn't "real" has no bearing on how accurately one can compute the evolution of some system's state through time.

nol13 10y ago
But how can you make accurate predictions about the future if time isn't real? Chew on that science boy.
- wolfgke 10y ago
  Even if time emerges from something different it is still there.
  - 10y ago

therestisgone 10y ago

Clickbait of the year. Yessss, keep feeding me more of those delicious downvotes.

dang 10y ago
We've banned this account for violating the HN guidelines.

Animats 10y ago

This is Smolin, making his usual, and valid, criticisms of modern physics. Smolin's basic complaint is that there is no experimental evidence for string theory. The math is pretty, and a whole generation of physicists have worked on it, but nothing is experimentally testable. Everything is too small or at too high an energy level. A practical implication is that it doesn't lead to any technology. Smolin also doesn't like many-worlds, because it talks about unreachable regions. This he considers too speculative. There's a basic problem in quantum mechanics, which leads to Schroedinger's Cat, the Copenhagen Interpretation, and, in the end, many-worlds.[1] Physics has been stuck on this problem for almost a century now. Philosophy won't help. [1] https://en.wikipedia.org/wiki/Copenhagen_interpretation https://en.wikipedia.org/wiki/Copenhagen_interpretation

dmfdmf 10y ago
> Physics has been stuck on this problem for almost a century now. Philosophy won't help. It sure seems to be an epistemology problem which puts it squarely in the realm of philosophy, not physics.
- xyzzyz 10y ago
  Maybe, but sadly philosophy doesn't have a good track record when it comes to actually solving problems.
  - ohyes 10y ago
    Bullshit. How do you think your computer functions? You don't get high level programming languages without philosophy. Where do you think natural sciences came from?
    - Numberwang 10y ago
      I think of philosophers as basically being 1000 Shakespearean monkeys. The world would be better served by 1000 scientists.

mstank 10y ago

As a layman, one thing I don't understand is why we suppose there has to be dark matter and energy in the universe. I understand that dark matter is used to explain gravitational irregularities when observing galaxies. However, saying 'there is x amount of unobservable stuff there' in order to make our calculations correct seems like lazy science. Are there any theories that don't include dark matter or energy? Can gravity function differently depending on its location (space or time) in the universe?

empath75 10y ago
https://en.wikipedia.org/wiki/Dark_matter#Alternative_theories https://en.wikipedia.org/wiki/Dark_matter#Alternative_theori... Yes. Hardly anyone takes them seriously, though, for a variety of reasons.
Manishearth 10y ago
> However, saying 'there is x amount of unobservable stuff there' in order to make our calculations correct seems like lazy science. That's not how this works. Dark matter and energy are placeholders for anything that can explain the discrepancy. The most likely explanation for dark matter is just undiscovered particles, but changing the physics of it to make the calculations come out right is also something that people do. There's not really a difference between the two either. Post-QFT the concept of a particle is much blurrier than before, and "changing the physics" might just involve introducing a new background field that behaves differently in different places based on its concentration. In essence, you have introduced a new particle. Please note that while it feels like lazy science, coming up with alternate theories that have the same success and rigor as QFT is very hard. Its not that they are hanging up their pencils and declaring premature victory. It is that literally the best description of physics out there to date doesn't explain this, and within that description yet-to-be-observed particles is its best bet. They are working on better explanations, but Rome wasn't built in a day.
- teamonkey 10y ago
  Here's an interesting theory. https://astronomynow.com/2016/06/16/did-gravitational-wave-detector-find-dark-matter/ https://astronomynow.com/2016/06/16/did-gravitational-wave-d... The gravitational waves we're detecting come from black holes, but the readings we have from LIGO suggest that they most likely come from 'primordial' black holes formed at the birth of the universe. If many of these black holes were formed they would be distributed much as MACHO theory predicts. 'Normal' black holes have very specific mass profiles so were generally ruled out as MACHOs, although obviously 'dark matter = black holes' has had a lot of consideration.

lolc 10y ago

I like how they see cosmologists as historians. Observe and describe the past, speculate, and muse about the future :-)

HillaryBriss 10y ago

> ... reification of mathematics can lead physicists into dangerous territory where mathematical "beauty" and "elegance" get substituted for real information about the real world. If it can happen in physics, it can happen anywhere -- maybe even your neighborhood.

vortico 10y ago

This was a pretty useless article with no real information or details to counter existing theories. I know the layman usually isn't interested in the details, but you can't just write about nothing. Are there consistent theories with those three features? What are features of existing models of cosmology which will have to be changed if the three features are assumed? The reader will never know.

empath75 10y ago

That we aren't capable of experiments that distinguish between various forms of string theories doesn't negate the fact that string theories are already compatible with all the experiments we've already done and are likely to be done in the near future. This is no small achievement. There is no other framework that is even in contention right now. Perhaps when we have some alternative theory that survives that basic hurdle, we can discuss whether we're wasting time pursuing string theory rather than some other idea.

Xcelerate 10y ago
> string theories are already compatible with all the experiments we've already done and are likely to be done in the near future Yeah, not enough people are aware of this in my opinion.
vacri 10y ago
> string theories are already compatible with all the experiments we've already done and are likely to be done in the near future So is the theory "A god did it".
jcranmer 10y ago
Supersymmetry is one (although it's not really a competitor to string theory, more an orthogonal theory). One of the complaints on string theory, as I understand it, is that it ends up being too general: it sort of implies that just about any phenomenon could be plausible, which makes it really hard to falsify. It's not so much that it's made predictions that turned out to be true, but rather that it can be accommodated to fit prior experiments. From a Bayesian perspective, we haven't received any evidence of its truth, only evidence of nontruth of other theories.
- auntienomen 10y ago
  This is a complaint rooted in sociology. People thought back in the 80s & 90s that string theory might be so constrained that can only describe one universe (presumably ours). They were wrong. String theory's more constrained than quantum field theory, but it's still capable of describing a lot of different universes. Most of the people who study it at the moment study it because it's been a fruitful source of ideas about quantum field theory. These people don't give press interviews very often, though.

jwatte 10y ago

You know what's cool? If they can reach better prediction, faster, with that approach, it will strengthen. If they can't, they will be a footnote. At least, if the scientific method is alive and well.

Manishearth 10y ago
The scientific method has been "on hold" in theoretical physics for a while; because our experimental technology just can't cope up with it. This is one of the main criticisms of string theory, for example.

mbfg 10y ago

> There is only one universe ok, except what else just has 1 of them > Time is real ask a photon that

Manishearth 10y ago
The whole "time is real" part of the article read like meaningless drivel to me. I have no idea what they were trying to communicate.
- mindcrime 10y ago
  As far as that goes, we arguably don't even know what time is.
  - Manishearth 10y ago
    That can be said of just about anything in physics.
    - mindcrime 10y ago
      Good point!
- sgt101 10y ago
  That the block universe model is just that : a model which is useful for solving problems, not a description of reality. This is a big problem for physics; confusing the modelling for truthiness. If you go for it all the way eventually you end up in a room with very, very think wallpaper engaging Max Telmark in a shouted conversation. This is part of the maths as selectively reflective of reality conversation.
  - Manishearth 10y ago
    > This is a big problem for physics; confusing the modelling for truthiness I'm pretty sure it isn't ; ever since quantum mechanics physicists have been very good at separating the two. Popsci, not so much, but the actual physics is very clear about it being a model.

deleted 10y ago

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RivieraKid 10y ago

I'm quite surprised that there's not a consensus about the philosophical framing of physics (metaphysics). The way I see it: - Consciousness (perceptions, feelings, thought) is the only thing that really exists. - There are patterns in what we perceive, for example, when we drop a rock, we see it falls and hear the impact. - So we develop models to describe patterns in our consciousness. Physics is just a description of those patterns. So the physical world doesn't really exist, it's just an idea in our minds.

ffwd 10y ago
The problem is this is self evident and doesn't explain anything. Saying that consciousness is the only thing that exists is like saying God created the universe. Well then who created God? We have to try to explain what all this is through our conscious experience, and if it happens to be that it's impossible for us to do so, we'll have to re-evaluate our options then. I personally don't believe this to be the case - I think everything exists and consciousness is only one way too perceive that everything, but that's another debate I guess
- RivieraKid 10y ago
  > The problem is this is self evident and doesn't explain anything. Definitely not self evident, vast majority of people don't see things this way. It doesn't have to explain anything, it's something akin to observation. Just a description of how things are, not an explanation. > Saying that consciousness is the only thing that exists is like saying God created the universe. I don't get this, how is this remotely similar, what does God have to do with this? The way I see it, history is just mental concept / idea. We take our physical model and similate the current state of the universe backwards - and call this history. > I personally don't believe this to be the case - I think everything exists and consciousness is only one way too perceive that everything, but that's another debate I guess Well, you only have perceptions (what you see, hear, feel, ...). It's the only thing you can be sure of. The "real world" is in its essence a thought, idea, mental model. Think about what does the statement "Eiffel tower exists" mean. It's a probabilistic statement about future perceptions - if you go to Paris, you will probably see it.

ianbicking 10y ago

If you disregard aesthetics, what are the questions we're trying to answer in physics, particularly those that involve observable phenomena? I get that string theory replicates the predictions of the theories that preceded it, the critique I'd infer is that it doesn't offer any practical advantages over the previous theories, it doesn't predict anything new that we can observe, and it does not make any problems more tractable (I think the opposite? Ie most problems are far more intractable using string theory) It seems like there's some lack of imagination here, like physics is "done", there's nothing more to answer, it's all just up to other sciences to answer the rest of the (many) questions about why the world is what it is and how it works. A reset of approaches is interesting, but it still needs to be in service of something, doesn't it?

burke 10y ago
> what are the questions we're trying to answer in physics, particularly those that involve observable phenomena? (disclaimer: I am not a physicist, etc.) Between GR and QM, we can explain most observable phenomena, but it's intuitively obvious that both are emergent properties of some deeper law. I don't suspect frontier physics is ever really studied with an eye to application. Those tend to follow, but the bleeding edge of physics is usually advanced just out of intellectual curiosity, to try to understand the universe. In this sense, String Theory is just an attempt the unify General Relativity with Quantum Mechanics. The fact that it's not apparently testable is unfortunate, We can have pedantic arguments about whether that's "Real Science", since science by definition requires testable hypotheses, but at the end of the day, I don't think it's crazy to pursue a model to encompass QM and GR, even if it can't be called "Science".
- ianbicking 10y ago
  > I don't suspect frontier physics is ever really studied with an eye to application. Previously they did have experimental results they were trying to understand. There might be follow up experiments to confirm, but there were already experimental tensions. > I don't think it's crazy to pursue a model to encompass QM and GR, even if it can't be called "Science". I'm not so concerned about whether something is science, it just seems like vanity to pursue unification that provides no insight into the complex world around us.

tamana 10y ago

NPR is not immune to betteridge's. Physics isn't "wrong" about string theory. String theory is a currently untestable theory, a mathematical model, and that's fine but minimally useful.

lossolo 10y ago

Hm i wonder why someone thought there is some invisible, unobservable dark matter instead connecting gravitational waves with super massive black holes in center of every galactic. It seems for me like a lot better answer to question what is keeping galaxies together if observable mass is not enough.

goodcanadian 10y ago
I found it a bit hard to understand before I actually took the course in university, but I'll try to explain simply: You can infer the mass that is interior to an orbit by measuring the speed at which an object is orbiting. By measuring the redshift and blueshift, we can get speeds of different parts of the galaxy. It turns out that we can account for more-or-less all of the mass near the centre of galaxies, but as we get further out, orbital velocities seem to be higher than they should be implying more mass is there than we can actually see. In other words, we can tell that the missing mass is not at the centre of the galaxy, but rather spread throughout it.
- lossolo 10y ago
  I see, it makes sense now, thank you for very clear explanation.

dc2 10y ago

I very proudly have not clicked the link, because it so such wild click bait, that it would be against my integrity.

joslin01 10y ago

Genuine confusion here -- how can you assert time is real? From my limited understanding, time is merely the measurement of change. A comet goes from point A to B, and like a screen flickering, it is in a discrete point in space every step along the way. It is time that is introduced when asking ourselves, "how long did it take?" or "when was it at X?" but how can it be woven into the fabric of the universe? If we take reality to be right here, right now, it doesn't seem to exist but rather is a human invention to help us map change.

Koshkin 10y ago
Thing to understand is that time is not a measurement, time is what we measure - as a phenomenon that has independent existence as part of the physical reality. More accurately (and perhaps more confusingly), time should be thought of as one of the aspects (components) of the 4-dimensional "spacetime", where spatial dimensions are, in fact, inseparable from the temporal dimension - so that the results of measurements of each component individually end up being dependent on the frame of reference.

perseusprime11 10y ago

This is like Fermat's last theorem. A whole lot of smart mathematicians spent their time solving this theorem instead of finding better things to solve that can benefit humanity.

auggierose 10y ago

They should take their own medicine. How would one test those three assumptions they make? As for Mathematics being selectively real, I agree with that totally. Mathematics is just a language we use to describe models and their properties in a most rigorous way. That's all. Can we find a model of the universe from which we can derive all its properties? Unlikely (see Gödel), if so the model would have to be pretty "primitive" and thus too large for comprehension. But so what, we can find great models for certain aspects of reality, and I don't see a limit for how far this can be taken to get better and better models for more and more areas of reality.

davesque 10y ago

To me, it's all a matter of the empirical data and the math that attempts to model that data. Those two sides of science have continually bootstrapped each other to the point we've arrived at today. Quoted from the book in the article: "Our mathematical inventions offer us no shortcut to timeless truth... They never replace the work of scientific discovery and of imagination. The effectiveness of mathematics in natural science is reasonable because it is limited and relative." I'm not sure what the authors mean by this. Are we to ultimately abandon our attempts at a consistent, logical explanation of what we see? If so, that's when we revert to un-scientific and, essentially, religious ways of thinking. I'd argue that the pursuit of a mathematical explanation of observations is the work of scientific imagination. Mathematics is merely the most reliable way we've devised of communicating what we imagine to other people. And sometimes the math, itself, sings to you and that drives advances in understanding that are totally valid.

eli_gottlieb 10y ago
Smolin wrote a paper on the "reasonable effectiveness" of mathematics in science. http://arxiv.org/pdf/1506.03733v1.pdf http://arxiv.org/pdf/1506.03733v1.pdf
- davesque 10y ago
  Thanks for this. Very interesting.

tvural 10y ago

Shallow criticisms of string theory usually miss how difficult it is to come up with physical theories that don't lead to some kind of contradiction. For this reason, lots of new physics has been discovered by looking at mathematical constraints first and experiments second. The math of string theory is pretty, but more importantly it works out, and this alone makes string theory worthy of some attention. If it's getting too much attention, that's probably more a sign that there are very few interesting research directions left in physics than that all the physicists are deluding themselves.

sova 10y ago

define event

dschiptsov 10y ago

Yes, by producing disconnected from reality abstractions.

andrewflnr 10y ago

"We're tired of the un-proven assumptions underlying modern physics. Here's some un-proven assumptions to get us back on track." What? How is this helping?

jnefbebyby 10y ago

I read this book a couple of years ago. About 1/3 (Smolin's) of it is really interesting. The main point about the primacy of Time is that traditional models of physics have an implicit time dimension for the laws, in additional the the time dimension of spacetime. Smolin suggests that the the laws of Physics are dynamical, evolving as a function of the state of the system.

erikb 10y ago

And yet, that's all the point of theoretical science. To think in ways even if they are not provable at this time. And then experimental scientists come along, look at the theories and then think about how to experiment on them. That's how it works. And I think if they want to disprove any of this they need to show that this system is broken. I need to google but I'm sure everybody can remember hearing a few times in their life that there were scientists like Einstein who had ideas that could not be proven in their life time but could be proven now with modern computers and now we know they were true. We admire that and we need that. And that's the thesis they need to fight if they want to convince me of theoretical science being wrong or bad.

dschiptsov 10y ago
Nope. The point of science is to follow scientific method, which is, contrary to the popular opinion, not about piling up meaningless abstractions cemented by dogmas and wishful thinking, but throwing every possible objection to the hypothesis, finding controversions and inconsistencies with other aspects of reality, and only when it stands nevertheless, that hypothesis could be accepted as a current approximation to the truth. This "science" is as bad pile of nonsense as Hegelian "philosophy".

andrewclunn 10y ago

Was expecting pseudo science based on the click-baity title. Instead got a take down of the pseudo science infecting cosmology. Nice.

abpavel 10y ago

In other news: 1. Time Gravitates! Physicists discover stable wormhole configuration by accounting the effect of gravity on time! and then 2. First wormhole to another universe successfully created! The final experimental proof of multiverse theory, which grants us access to all 10^500 universes, and any place in our own corner of the world" and then 3. Now in portable format, just for $299! Stop being impatient!

DrNuke 10y ago

Problem with philosophy is that it views all anthropocentric. On the other hand, we are beyond anthropocentrism in modern physics in the sense that sensorial / bodily experience (our way to interact with the outer world) doesn't help any more and thinking / mind abstraction (our special way to represent the outer world) is unprovable because technologies and tools are not there yet. More than philosophy, it is literature to stand up when we need a change of paradigm, in particular science fiction: minds trying to carve skewed views of the universe starting from non-mainstream philosophy. Suffice to say, it will be many more misses than hits but gold is there.

spacehome 10y ago
I didn't understand any of that.
- DrNuke 10y ago
  It's literature before philosophy and physics.

nsuser 10y ago

Nice clickbait title..

tim333 10y ago

While I agree with Smolin that much physics has moved away from experimental observation, especially string theory, I think the three numbered points in the article are wrong. My take - the only way the universe could have got here from nothing as it were is if it's basically maths and seems real to us. I mean what does basic particle behavior look like - a bunch of maths and not much else, and what exist without needing creating - mathematical patterns and relations and nothing else. Hence from observation it's probably all maths. Hence: 1) There is only one universe. - Nah probably all mathematically possible universes seem real to their occupants. 2) Time is real. - Sorta but more like how time exists in a DVD of a movie. Or as some guy wrote "...for us physicists believe the separation between past, present, and future is only an illusion, although a convincing one." 3) Mathematics is selectively real. - Nah it's real.

deleted 10y ago

[deleted]

jokoon 10y ago

Logical and structured thinking is good tool when doing physics, because a precise model can be used as a language and communicated and taught, since it's simple. But those models are correct only in what they describe, they don't completely describe nature. They are just that, models. Every time science has progressed, it's either an "exception to the rule", or a re-understanding of an incomplete theory. I'm not a scientist, but I vividly remember how a physics professor warned us about the laws he was teaching. Those laws work well, use them, but never pretend that they're universal and that they will be for the next 20 or 100 years. You can see this problem in quantum mechanics. Quantum mechanics is being very hard on philosophy and certainty in general. Up to a point, using models might be a limit to physics.

cmplxconjugate 10y ago
I am a physicist and one thing that you realise, as you develop as a scientist, is the fact that the perception that "physics describes everything perfectly" is not true. When you start out, lets say as an undergraduate, you feel the pressure to be "correct". You struggle to find the correct answers or construct them. The breakthrough comes when you realise that we use mathematics as a tool to extract answers; we do our best to make the best educated guess we can and interpret the results. A great example would be with something like density functional theory (DFT), where we make extremely crude approximations for exchange and correlation functionals. By understanding the limits of our model we can use this information to improve the results; as Feynman said: "The first job of a theoretical physicist is to prove yourself wrong as fast as possible". I'm not sure I agree with your last statement: >Up to a point, using models might be a limit to physics. I argue that this is the most important thing to physics. The moment you start to leave a model, you allow for subjective speculation. I argue that this has no place in physics and is the prime reason that physics has broken away from philosophy.
- jokoon 10y ago
  > you allow for subjective speculation Don't you need to speculate at one moment or another to improves physics? Of course you can only do that once you studied physics a lot, but if you want to be creative in physics, don't you have to "speculate" that work with the data?

williesleg 10y ago

Scientists are wrong to believe all that exists can be perceived by our senses, or envisioned in our minds. We are a small minute subset of what is out there. A pimple on the ass of the universe.

garyclarke27 10y ago

I agree with much of the sentiment such as string theory and multi universes are nonsense. Yes math is just an abstraction tool, with mutually understood/ agreed rules , the rules and representations are not exactly true in the real world, users just agree them to assist with communication between users and over time. Time is Not Real, it's an abstraction / quantification of change, but yes change is I think real i.e. the universe is always changing. However his statement- Our ability to map out the history of the universe back to a fraction of an instant after its inception is a triumph - ruined it for me - an absurd statement for a scientist - we have no idea how the universe started we are only guessing it's history, the big bang theory is just a theory, probably no more real than Lord of the Rings.

Tyr42 10y ago
Sounds like you haven't seen much of the evidence for big bang theory. I'm going to call your attention to the COBE mission. http://science.nasa.gov/missions/cobe/ http://science.nasa.gov/missions/cobe/ This took the predictions from the big bang theory about a small hot dense universe, and measured the cosmic background radiation, and it matched perfectly. The idea is that when the universe was young, it was so hot that all the matter was in a plasma cloud, and that photons (and other EM radiation) couldn't travel very far at all before being absorbed and re-emitted in a random direction. Then, the universe expanded and cooled enough that the cloud became transparent. But there were still those photons (etc) that now just kept going in all directions. Some of them happen to be arriving from all directions no matter where you are (unless you're on the rim of the universe or something). That's the cosmic background radiation. And we measured it, and it matched so well with the predicted numbers it was astounding. This is also the graph that shows up on the "Science, it works bitches!" xkcd shirt. https://www.explainxkcd.com/wiki/index.php/54:_Science https://www.explainxkcd.com/wiki/index.php/54:_Science

peterburkimsher 10y ago

Betteridge's law of headlines: "Any headline that ends in a question mark can be answered by the word no." Has the Hacker News upvote system gotten something really important really wrong?