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I'm really fascinated by the idea that physics might be completed in my lifetime. I know it's a naive point of view - people thought the same around 1900, just

I'm really fascinated by the idea that physics might be completed in my lifetime. I know it's a naive point of view - people thought the same around 1900, just before quantum mechanics and special relativity were discovered. I also realise that CERN hasn't made the breakthrough researchers hoped for. But what if the idea of long-lived particles, or another theory, comes good? It reconciles the standard model with relativity and explains dark matter, and then... it's all over. The rest is tidying up details. Wouldn't that be the strangest time to be alive? I think some people would be disappointed, but I'd be thrilled.

renox 10y ago
>I'm really fascinated by the idea that physics might be completed in my lifetime. ? Unlikely, given the current situation where there isn't much real progress toward unification of QM and gravity..
chriswarbo 10y ago
I think it depends on how 'chaotic' new discoveries are. For example, discovering relativity helped us to explain the world as it already was; e.g. it explained the precession of Mercury's orbit, but Mercury's orbit was already precessing. On the other hand, since we discovered quantum mechanics, it's affected many aspects of the world. Many quantum effects only cause small deviations in measurements, similar to those of relativity, and naturally "average out" on the macro scale. Yet once we noticed them, we were able to amplify these effects, and now quantum devices like semiconductors are all over the place; even something mundane like the postal service now involves computers, and hence to be explained fully requires quantum mechanics. I can imagine a future where all of our discoveries are of the relativity kind; i.e. making more precise predictions of some measurements, and having little effect outside of those measurements (although relativity has certainly changed our perspective and interpretation of the universe!) I can also imagine a future where we discover some minor correction to a measurement, say a slight shift in the spectral lines of novae, which is explained via an effect we can harness and which will affect all manner of things in the way quantum physics has. For example, maybe the discrepancy is explained as a weak gravitational repulsion; or due to matter making short jumps through time; or some other phenomenon which affects natural systems in subtle ways, but which we can amplify artificially to have far reaching effects.
- XorNot 10y ago
  http://www.nature.com/nature/journal/v436/n7047/full/436150a.html http://www.nature.com/nature/journal/v436/n7047/full/436150a... Nature publishes short sci-fi stories in each issue. This one is kind of amazing.
  - chriswarbo 10y ago
    Well, it's a little amusing I suppose, but I don't see what makes it 'kind of amazing'. I never understood claims like "if there's no free will, why do anything?"; it doesn't matter whether something's deterministic or not, only whether it's predictable or not. The only non-BS form of "free will" I've come across is Wolfram's approach of computational irreducibility, where "I" am the computational process which calculates my behaviour. From that perspective, even if someone can predict my behaviour and choices with 100% accuracy, it's still "me" making those choices, since their model of me is just another instance of me. Everything else is just geocentric fairytales.
    - AnimalMuppet 10y ago
      If there's no free will, why do anything? Because I can't not do it, because I have no free will...
    - XorNot 10y ago
      I like the hook of 1 second negative-time circuits being mass produced. So much so you can put them on keychains, buy them at a dollar shop, whatever. That's the thing you really need to imagine: a world filled with gadgets more common then iPhones, that do a very trivial bit of future prediction that massively undermines our entire perception of reality.
  - teraflop 10y ago
    There's a similar idea in Greg Egan's recent Orthogonal trilogy [1]. It's a fascinating series that explores a universe with different law of physics from our own, with the physical implications worked out in considerable detail. One of the more intriguing (although hand-wavy) ideas is that in this universe, it's fairly straightforward to construct a device to send information backwards in time -- but if you actually do so, social and technological progress will immediately grind to a halt, on purely thermodynamic grounds. The idea is that any information that you send back seems to "appear from nowhere" as part of a stable causal loop, and so the entropically-favored outcomes are the ones where as much of the information as possible is uninteresting. [1] http://www.gregegan.net/ORTHOGONAL/ORTHOGONAL.html http://www.gregegan.net/ORTHOGONAL/ORTHOGONAL.html
saiya-jin 10y ago
we might also find out that there is no real way to travel faster than light, bounding us to colonizing few nearby star systems at best (which might be utterly inhabitable without massive terraforming), a rather depressing thought.
- maze-le 10y ago
  > we might also find out that there is no real way to travel faster than light We don't need to find that out, we already know that
  - bbctol 10y ago
    Well, there certainly seems to be no way for anything to move faster than light through spacetime. It's harder to rule out exotic matter or negative energy that could warp spacetime to (relatively) move an object faster than light.
- XorNot 10y ago
  Of course if computing power proceeds to its logical bounds, we'll have more then enough capacity to sustain thousands of personalities in substrate the same size as the human head. And once we're all immortal infomorphs, "time" - and thus distance, may end up having very different meanings to us. EDIT: Basically just go read Accelerando for a pretty good take on this whole idea (it's free online).
  - nitrogen 10y ago
    Also read Permutation City, Diaspora, and Schild's Ladder by Greg Egan. If you only read one, read Schild's Ladder.
throwaway000002 10y ago
> I'm really fascinated by the idea that physics might be completed in my lifetime. That's an unfortunate thought to be fascinated by. You should study some physics, instead of reading popular articles about it, or even what pre-eminent physicists say about their work. I can simply illustrate the situation by saying if a question Q eventually provides answer A, the a new question Q' arises: why A? You can tell yourself "it doesn't matter" but quite frankly, at the human scale, physics is already a done deal. Which only further illustrates why your thought is a bit naïve.
- jimmytidey 10y ago
  I certainly could read more, but I do have a degree in physics and philosophy. Certainly there will always be questions like: why something rather than nothing? However, if you have a (relatively) simple set of rules, like the standard model, which work in every context and (in principle) predicts all observable phenomena, it does seem like you've crossed some kind of threshold. An intellectual threshold - as you say it has limited practical implications. It would be a watershed like observing alien bacteria. You're not going to do much with it, but it seems to put you in touch with the cosmic. There might still be lots of emergent phenomena we don't fully understand, but we could still be confident that the underlying physics is totally understood. An example of this might be the Navier–Stokes equation - we don't fully understand it, but I don't think many people think that a complete understanding of why nature obeys this law will lead to any fundamentally new physics. It's certainly possible it's just questions all the way down, perhaps smaller and smaller structures will be observable at higher energies, but it's an open question. Another option is that we're close to bottoming out all of the complexity - and that's the possibility I find fascinating. I'm not envisioning a time when every possible question has been answered, instead I'm thinking of a time when any questions about fundamental physics will either have been answered or we can be satisfied that no empirical evidence will answer them. QM may already have hit this knowledge barrier. We know from Bell inequities there are no hidden variables, there is simply no empirical way to predict with certainty the state of a quantum system. We've hit the edge of the knowable. "Whereof one cannot speak, thereof one must be silent" - as Wittgenstein might have said about the situation. In defence of throwaway000002, when I talk with physicists about the idea that physics might be completed they mostly don't think it's likely. I don't think they subscribe to the questions all the way down model, instead they think we have a long way to go yet - though I think most researchers don't have clearly formed views on the subject.
ISL 10y ago
It's questions all the way down. Even if we knew the complete theory of everything, the immediate question would become, "Why is the theory of everything the exact theory of everything?"
- deleted 10y ago
  [deleted]
- hleszek 10y ago
  Because of the Anthropic principle !
  - jimmytidey 10y ago
    Conceivably, you could have empirical evidence for multiple universes, at which point the anthropic principle becomes a normal explanation. Until then, obvious it remains a bit of a non-explanation.
    - platz 10y ago
      I hate the Anthropic principle.. it appears to be able to justify anything
      - M_Grey 10y ago
        You should hate anything that isn't testable and falsifiable, that's good hatred.
        platz 10y ago
        Thanks!
        bertiewhykovich 10y ago
        Why? What fundamental reason is there to reject the untestable and the unfalsifiable? At worst, these claims fall into an epistemological netherworld where they can neither be ascribed truth nor falsity -- at best they may be useful tools.
M_Grey 10y ago
We're not even remotely close, but if it makes you feel any better, people have been speculating about an end to physics for... well... you're in centuries of good company at least.
beevai142 10y ago
Condensed-matter physics and chemistry have been "complete" in this sense since forever. You can write down on a small piece of paper the Hamiltonian of electrons interacting via electromagnetic forces with themselves and the atom nuclei. And that's pretty much it.
Razengan 10y ago
As a complete layman trying to grok the physics of our reality's fundamentals, now and then during the occasional Wikipedia excursions, I get the feeling that there is no way there are only 3 physical dimensions, and that we as beings rooted in 3D may never be able to see the full picture first-hand. I think having visual eyesight also makes us heavily biased towards picturing everything as ultimately made up of discrete "particles," and as far as I can tell, our instruments are also limited by trying to distill the results of our experiments into visual images, which results in things like the "wave-particle duality" conundrum.

renox 10y ago

>I'm really fascinated by the idea that physics might be completed in my lifetime. ? Unlikely, given the current situation where there isn't much real progress toward unification of QM and gravity..

chriswarbo 10y ago

I think it depends on how 'chaotic' new discoveries are. For example, discovering relativity helped us to explain the world as it already was; e.g. it explained the precession of Mercury's orbit, but Mercury's orbit was already precessing. On the other hand, since we discovered quantum mechanics, it's affected many aspects of the world. Many quantum effects only cause small deviations in measurements, similar to those of relativity, and naturally "average out" on the macro scale. Yet once we noticed them, we were able to amplify these effects, and now quantum devices like semiconductors are all over the place; even something mundane like the postal service now involves computers, and hence to be explained fully requires quantum mechanics. I can imagine a future where all of our discoveries are of the relativity kind; i.e. making more precise predictions of some measurements, and having little effect outside of those measurements (although relativity has certainly changed our perspective and interpretation of the universe!) I can also imagine a future where we discover some minor correction to a measurement, say a slight shift in the spectral lines of novae, which is explained via an effect we can harness and which will affect all manner of things in the way quantum physics has. For example, maybe the discrepancy is explained as a weak gravitational repulsion; or due to matter making short jumps through time; or some other phenomenon which affects natural systems in subtle ways, but which we can amplify artificially to have far reaching effects.

XorNot 10y ago
http://www.nature.com/nature/journal/v436/n7047/full/436150a.html http://www.nature.com/nature/journal/v436/n7047/full/436150a... Nature publishes short sci-fi stories in each issue. This one is kind of amazing.
- chriswarbo 10y ago
  Well, it's a little amusing I suppose, but I don't see what makes it 'kind of amazing'. I never understood claims like "if there's no free will, why do anything?"; it doesn't matter whether something's deterministic or not, only whether it's predictable or not. The only non-BS form of "free will" I've come across is Wolfram's approach of computational irreducibility, where "I" am the computational process which calculates my behaviour. From that perspective, even if someone can predict my behaviour and choices with 100% accuracy, it's still "me" making those choices, since their model of me is just another instance of me. Everything else is just geocentric fairytales.
  - AnimalMuppet 10y ago
    If there's no free will, why do anything? Because I can't not do it, because I have no free will...
  - XorNot 10y ago
    I like the hook of 1 second negative-time circuits being mass produced. So much so you can put them on keychains, buy them at a dollar shop, whatever. That's the thing you really need to imagine: a world filled with gadgets more common then iPhones, that do a very trivial bit of future prediction that massively undermines our entire perception of reality.
- teraflop 10y ago
  There's a similar idea in Greg Egan's recent Orthogonal trilogy [1]. It's a fascinating series that explores a universe with different law of physics from our own, with the physical implications worked out in considerable detail. One of the more intriguing (although hand-wavy) ideas is that in this universe, it's fairly straightforward to construct a device to send information backwards in time -- but if you actually do so, social and technological progress will immediately grind to a halt, on purely thermodynamic grounds. The idea is that any information that you send back seems to "appear from nowhere" as part of a stable causal loop, and so the entropically-favored outcomes are the ones where as much of the information as possible is uninteresting. [1] http://www.gregegan.net/ORTHOGONAL/ORTHOGONAL.html http://www.gregegan.net/ORTHOGONAL/ORTHOGONAL.html

saiya-jin 10y ago

we might also find out that there is no real way to travel faster than light, bounding us to colonizing few nearby star systems at best (which might be utterly inhabitable without massive terraforming), a rather depressing thought.

maze-le 10y ago
> we might also find out that there is no real way to travel faster than light We don't need to find that out, we already know that
- bbctol 10y ago
  Well, there certainly seems to be no way for anything to move faster than light through spacetime. It's harder to rule out exotic matter or negative energy that could warp spacetime to (relatively) move an object faster than light.
XorNot 10y ago
Of course if computing power proceeds to its logical bounds, we'll have more then enough capacity to sustain thousands of personalities in substrate the same size as the human head. And once we're all immortal infomorphs, "time" - and thus distance, may end up having very different meanings to us. EDIT: Basically just go read Accelerando for a pretty good take on this whole idea (it's free online).
- nitrogen 10y ago
  Also read Permutation City, Diaspora, and Schild's Ladder by Greg Egan. If you only read one, read Schild's Ladder.

throwaway000002 10y ago

> I'm really fascinated by the idea that physics might be completed in my lifetime. That's an unfortunate thought to be fascinated by. You should study some physics, instead of reading popular articles about it, or even what pre-eminent physicists say about their work. I can simply illustrate the situation by saying if a question Q eventually provides answer A, the a new question Q' arises: why A? You can tell yourself "it doesn't matter" but quite frankly, at the human scale, physics is already a done deal. Which only further illustrates why your thought is a bit naïve.

jimmytidey 10y ago
I certainly could read more, but I do have a degree in physics and philosophy. Certainly there will always be questions like: why something rather than nothing? However, if you have a (relatively) simple set of rules, like the standard model, which work in every context and (in principle) predicts all observable phenomena, it does seem like you've crossed some kind of threshold. An intellectual threshold - as you say it has limited practical implications. It would be a watershed like observing alien bacteria. You're not going to do much with it, but it seems to put you in touch with the cosmic. There might still be lots of emergent phenomena we don't fully understand, but we could still be confident that the underlying physics is totally understood. An example of this might be the Navier–Stokes equation - we don't fully understand it, but I don't think many people think that a complete understanding of why nature obeys this law will lead to any fundamentally new physics. It's certainly possible it's just questions all the way down, perhaps smaller and smaller structures will be observable at higher energies, but it's an open question. Another option is that we're close to bottoming out all of the complexity - and that's the possibility I find fascinating. I'm not envisioning a time when every possible question has been answered, instead I'm thinking of a time when any questions about fundamental physics will either have been answered or we can be satisfied that no empirical evidence will answer them. QM may already have hit this knowledge barrier. We know from Bell inequities there are no hidden variables, there is simply no empirical way to predict with certainty the state of a quantum system. We've hit the edge of the knowable. "Whereof one cannot speak, thereof one must be silent" - as Wittgenstein might have said about the situation. In defence of throwaway000002, when I talk with physicists about the idea that physics might be completed they mostly don't think it's likely. I don't think they subscribe to the questions all the way down model, instead they think we have a long way to go yet - though I think most researchers don't have clearly formed views on the subject.

ISL 10y ago

It's questions all the way down. Even if we knew the complete theory of everything, the immediate question would become, "Why is the theory of everything the exact theory of everything?"

deleted 10y ago
[deleted]
hleszek 10y ago
Because of the Anthropic principle !
- jimmytidey 10y ago
  Conceivably, you could have empirical evidence for multiple universes, at which point the anthropic principle becomes a normal explanation. Until then, obvious it remains a bit of a non-explanation.
  - platz 10y ago
    I hate the Anthropic principle.. it appears to be able to justify anything
    - M_Grey 10y ago
      You should hate anything that isn't testable and falsifiable, that's good hatred.
      - platz 10y ago
        Thanks!
      - bertiewhykovich 10y ago
        Why? What fundamental reason is there to reject the untestable and the unfalsifiable? At worst, these claims fall into an epistemological netherworld where they can neither be ascribed truth nor falsity -- at best they may be useful tools.

M_Grey 10y ago

We're not even remotely close, but if it makes you feel any better, people have been speculating about an end to physics for... well... you're in centuries of good company at least.

beevai142 10y ago

Condensed-matter physics and chemistry have been "complete" in this sense since forever. You can write down on a small piece of paper the Hamiltonian of electrons interacting via electromagnetic forces with themselves and the atom nuclei. And that's pretty much it.

Razengan 10y ago

As a complete layman trying to grok the physics of our reality's fundamentals, now and then during the occasional Wikipedia excursions, I get the feeling that there is no way there are only 3 physical dimensions, and that we as beings rooted in 3D may never be able to see the full picture first-hand. I think having visual eyesight also makes us heavily biased towards picturing everything as ultimately made up of discrete "particles," and as far as I can tell, our instruments are also limited by trying to distill the results of our experiments into visual images, which results in things like the "wave-particle duality" conundrum.