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Gravity: We might have been getting it wrong
- mindcrime 7y agoHuh, interesting. We know there are (or were) some fundamental asymmetries in the universe, leading to, for example, the imbalance in matter vs anti-matter. I wonder if this research will lead to anything in terms of understanding why these kinds of asymmetries exist?
- Ididntdothis 7y agoAn interesting question is also why the universe has any kind of structure and is not uniform.
- greesil 7y agoThis part is fun: "Their result has several important consequences. In particular, it predicts that the protons are unstable against decaying into other elementary particles, and that magnetic monopoles exist."
- alextingle 7y agoThat caught my eye too. Magnetic monopoles would be very useful, if we could find them.
- greesil 7y agoWhat would you do with a magnetic monopole? I might make this an interview question at work. Hmmm
- hnuser123456 7y agoMake an infinite energy machine by having magnets on a rotor, surrounded by monopoles on a stator (or vice versa), so the rotor is infinitely accelerated with no external input energy. Hook it up to an alternator and harness the free power.
- jcranmer 7y agoI'm pretty sure that doesn't work for the same reason that replacing monopoles with charged objects (which we can actually build!) doesn't produce a perpetual motion machine.
- deleted 7y ago[deleted]
- paulpauper 7y agothis article is way to vague. Do they means symmetry as it relates to string theory or some other theory for quantum gravity? I was hoping for more info.
- xhkkffbf 7y agoIf we can't figure out gravity, what hope have we of doing ANY science? I mean stuff falls. Everything falls. The orbits of the planets aren't that complex, but gravity pretty much predicts them close to perfectly.
- gumby 7y agothis pop sci article does address that: we have a good theory of gravity at macroscopic scale but none at the quantum level.
- jdkee 7y ago"Science is magic that works." -K. Vonnegut
- Koshkin 7y agoThere'also Clarke's Third Law.
- hannob 7y agoI don't understand a lot about how the computer in front of me works (ok, I know more than the average person, but still I don't know a whole lot). Yet I'm still able to use it. We understand enough of the effects gravity to describe most phenomena that are relevant for most other parts of science. From my lay understanding what physicists are missing is how to tie in gravity with all the other theories they believe are true. However the effects, whatever they are, are so small that we can in most cases just ignore them.
- dwaltrip 7y agoWe have a working model of gravity that is very accurate in an incredibly broad array of circumstances. You acknowledge this in your comment. This is a scientific result. What are you trying to say?
- empath75 7y agoHow does gravity impact photons and quarks? That’s the part that’s missing.
- tiborsaas 7y agoEven the title is wrong, we know for a fact that we are getting gravity wrong. A better article with actual content: https://www.ipmu.jp/en/20190619-symmetry https://www.ipmu.jp/en/20190619-symmetry
- glofish 7y agoTLDR: [...] the holographic principle allows physicists to study gravitational systems by projecting them on a boundary [...] proved that symmetry is not possible in a gravitational theory if it obeys the holographic principle. [...] meaning that symmetry would not be possible in quantum gravity.
- deleted 7y ago[deleted]
- Khaine 7y agoPBS Space Time have done a number of episodes on the holographic principle[1] I strongly recommend anyone interested in physics check out the channel [1] https://www.youtube.com/watch?v=klpDHn8viX8 https://www.youtube.com/watch?v=klpDHn8viX8
- RandomBacon 7y agoFor people on a mobile device: > TLDR: > the holographic principle allows physicists to study gravitational systems by projecting them on a boundary > proved that symmetry is not possible in a gravitational theory if it obeys the holographic principle. > meaning that symmetry would not be possible in quantum gravity.
- foobar1962 7y ago... if it obeys the holographic principle.
- hinkley 7y agoBy inference. this means we trust the holographic principle so thoroughly that we don't even consider that it could be the unbalanced part of this equation. Is that true?
- wrycoder 7y agoMuch more information from a previous phys.org: https://phys.org/news/2019-05-constraints-symmetries-holography.html https://phys.org/news/2019-05-constraints-symmetries-hologra... Their work assumes the AdS/CFT correspondence. "Our new paper provides a rigorous proof of this claim in the context of the AdS/CFT correspondence, where quantum gravity is defined in a mathematically precise way, and we have done so in the most general way, excluding all possible global symmetries from quantum gravity,"
- scrumper 7y agoAgh, mildly infuriating (enfrustrating?) article. A little tease about the result and then several paragraphs about how science is serendipitous and face to face interactions are better than email and video conferencing.
- pdonis 7y ago> mildly infuriating (enfrustrating?) article Par for the course for phys.org.
- reggieband 7y agoInteresting ... another time holography in the context of physics has come up. Youtube recommended the Wired series where some expert explains some concept at different levels and one recent one was on Gravity [1]. In the expert section they talk briefly about holography and how a two dimensional surface seems to be able to encode all of the information of a three dimensional volume. They go on to speculate how this might relate to the event horizon of black holes. I get a bit lost since it is heavily edited and they are clearly talking about things beyond my ken. My takeaway was that there is a possibility the information we thought was getting lost within blackholes is actually still present within the surface of the event horizon. There was also a brief mention of holography in this interview with String Theorist Jim Gates on Lex Fridman's Youtube channel [2]. I can't remember the exact context of how holography is related to strings but I believe he was talking about how it could impact some of the maths behind the multiple dimensions some string theories required. [1] https://www.youtube.com/watch?v=QcUey-DVYjk https://www.youtube.com/watch?v=QcUey-DVYjk [2] https://www.youtube.com/watch?v=vGQ3q4dO_9s https://www.youtube.com/watch?v=vGQ3q4dO_9s
- sebow 7y agoMaybe when the scientific community will abandon the arrogance and piggy-backing mentality upon theories are built and upon which ideas are accepted into testing, we will actually get more results as a species. Then again, history has shown that real work is done by the outliers, people who think outside of the norm of stupid masses.
- tus88 7y agoHuh. We said the same thing a bit over a century ago.
- foxes 7y agoSee [0] for the actual paper mentioned in the article. [0] https://arxiv.org/abs/1810.05338 https://arxiv.org/abs/1810.05338
- rubyn00bie 7y agoBecause like every article I tried to find was pretty much the exact same rubbish overview, here's a link to the pre-print paper: https://arxiv.org/pdf/1810.05337.pdf https://arxiv.org/pdf/1810.05337.pdf As someone very not versed in physics, the paper is actually... really readable so far and short (I'm almost done). At the very least, there is more information than anything mentioned in the links/summaries I could find.
- s1dev 7y agoThe real paper is https://arxiv.org/pdf/1810.05338.pdf https://arxiv.org/pdf/1810.05338.pdf 1810.05337 is a summary of results for PRL Both are very good
- JadeNB 7y agoEternal plea: for those of us who want to see what the paper's about before downloading it, it's better to link to the abstract at http://arxiv.org/abs/1810.05338 http://arxiv.org/abs/1810.05338 .
- ksaj 7y agoModeling, even if incorrect, is important for at least 2 reasons. The most obvious one is that we can refine the theory as new results come out of the experiments. The second is that a successful model, even if wrong for the experiment it was devised, will eventually shed light on a similar problem elsewhere.
- rehasu 7y agoIf you talk to physicists and they tell you we've got something right, stop talking to them. Every good(!) one knows that we got it wrong. Just a little less wrong than in the previous model. You cannot get it right. It wouldn't be a model but reality as a whole if you got it right. So the only questions are how you can get it less wrong than the last model, and which of the available models is most useful for the problem you are currently tackling. So yes, sometimes you even want to use a more-wrong model because it fits your problem better. edit: thought about bringing in an example, but honestly it would need too much googling to be precise enough.
- edem 7y ago> sometimes you even want to use a more-wrong model because it fits your problem better. Or they are equal in fit, but the more wrong is easier to use.