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It's a problem, because we are no closer to answering questions like: - what is dark matter (the stuff which makes up 97% of the universe!) - what is dark ene

It's a problem, because we are no closer to answering questions like: - what is dark matter (the stuff which makes up 97% of the universe!) - what is dark energy (I.e. Why is the universe expanding at an accelerating rate?) - what happens inside a black hole? - what happened at the big bang? - how does gravity work at the quantum scale? The Standard Model has nothing to say on these, it is fundamentally incomplete. I fear we won't answer these questions within my lifetime, sure, we may get tantalising hints from astronomy, but not direct observation in experiment. This is troubling for theoretical physics, it needs guidance by experimental physics. But all these super-smart theories to supersede the SM cannot be verified by experiment right now.

aaaaaaaaaab 8y ago
Errata: * purported dark matter * purported dark energy * purported black holes * purported big bang
- codethief 8y ago
  I wouldn't put dark energy, black holes and the big bang on a level with dark matter. Dark energy is just a name for what's otherwise known as cosmological constant. Yes, some people might believe that it's unnatural for the cosmological constant to be as small as it is and others might believe that it should really follow from a proper quantum theory, so there are definitely a bunch of open questions. But that doesn't change the fact that it's there. The same thing goes for the Big Bang and black holes. We have absolutely no reason to believe they don't exist. (To the contrary, we have every reason to believe so.) Dark matter, however, is just one possible (and comparatively speculative) explanation for various experimental deviations from theoretical predictions, regarding among others the stellar velocity distribution within galaxies, gravitational lensing and structure formation.
- cambalache 8y ago
  * purported atoms * purported molecules * purported cells * purported persons
- rstuart4133 8y ago
  Yes, you are right, dark matter,and the big bang are just the leading theories explaining an observed feature of our universe: - What is holding the galaxies together, given they are rotating faster than gravity from observable matter can cope with? - Why is the Universe so uniform, given parts of it we can see are outside of each others light cones? I read the OP as using the names of these theories as a handle for the effects they account for, which is fairly standard practice. Even physicists investigating other explanations do this. I'm not sure dark energy or black holes fit that description. "Dark energy" is a reference to something that is causing distance objects to accelerate away from us faster than near objects. Obviously that takes energy. Dark energy is just a place holder name for that energy given we don't have a clue what it is or where it comes from. A black hole is a name for enormously heavy, small (smaller than the schwartz radius) and very dark objects whose existence is inferred from the their gravitational effects. They are found at the centre of galaxies, among other places.
guscost 8y ago
I would not be surprised if someday more than one of your first four questions are all resolved by the discovery that theoreticians have made a bad assumption, and have been chasing today’s phlogiston or aether. This might coincide with the discovery of a new theory answering (or proving unanswerable) the fifth question as well. Or, all the necessary “fixes” to the Standard Model are out there. Either way, I agree that it might be another long wait before our technology can find meaningful new constraints.
DiabloD3 8y ago
More to the point, the LHC has not answered the following questions: were we correct in thinking dark matter and dark energy exist (ie, physics did not accidentally mistake the map for the territory), that we were correct in thinking black holes actually do exist (and it isn't an entirely different phenomenon involving extremely high energy plasmoids or something even weirder), and that the big bang actually happened (and that the universe is indeed expanding).
- codethief 8y ago
  You can formulate all kinds of questions a given experiment like the LHC didn't answer but unless the experiment actually set out to answer these questions in the first place, you're mostly just talking about the empty set. Namely, the LHC was never directly concerned with black holes, the Big Bang, dark energy and dark matter. (Outside of the possibility that completely new physics would be found and that this would somehow lead to an explanation of dark matter, dark energy and/or quantum gravity down the road.) Moreover, I'm also not sure why you're casting doubt on dark energy (= the cosmological constant), the Big Bang and black holes. There are certainly many aspects about them we don't fully understand yet but their existence is generally not disputed.
cygx 8y ago
what is dark matter (the stuff which makes up 97% of the universe!) That's a ballpark figure for dark energy + dark matter combined.
iamgopal 8y ago
I was even hoping for big bang created again inside LHC.
- akvadrako 8y ago
  Maybe it happened, but it created another universe and we never noticed.
  - zyxzevn 8y ago
    Maybe .. the other universe also contained life and sentient beings. But as they were aggressive and tried to invade our world. So the scientists decided to stop the experiment and never to tell anyone about it.
User23 8y ago
> The Standard Model has nothing to say on these, it is fundamentally incomplete. I fear we won't answer these questions within my lifetime, sure, we may get tantalising hints from astronomy, but not direct observation in experiment. One of my coworkers is a trained particle physicist, and he will be the first to say that the standard model is a mess and nobody in the field actually believes it's correct, just that it's what they currently have to work with. He describes it as basically a switch statement depending on the field in question. None of this is meant to denigrate the endeavor, it's just that nuclear physics makes electrodynamics look like child's play.

aaaaaaaaaab 8y ago

Errata: * purported dark matter * purported dark energy * purported black holes * purported big bang

codethief 8y ago
I wouldn't put dark energy, black holes and the big bang on a level with dark matter. Dark energy is just a name for what's otherwise known as cosmological constant. Yes, some people might believe that it's unnatural for the cosmological constant to be as small as it is and others might believe that it should really follow from a proper quantum theory, so there are definitely a bunch of open questions. But that doesn't change the fact that it's there. The same thing goes for the Big Bang and black holes. We have absolutely no reason to believe they don't exist. (To the contrary, we have every reason to believe so.) Dark matter, however, is just one possible (and comparatively speculative) explanation for various experimental deviations from theoretical predictions, regarding among others the stellar velocity distribution within galaxies, gravitational lensing and structure formation.
cambalache 8y ago
* purported atoms * purported molecules * purported cells * purported persons
rstuart4133 8y ago
Yes, you are right, dark matter,and the big bang are just the leading theories explaining an observed feature of our universe: - What is holding the galaxies together, given they are rotating faster than gravity from observable matter can cope with? - Why is the Universe so uniform, given parts of it we can see are outside of each others light cones? I read the OP as using the names of these theories as a handle for the effects they account for, which is fairly standard practice. Even physicists investigating other explanations do this. I'm not sure dark energy or black holes fit that description. "Dark energy" is a reference to something that is causing distance objects to accelerate away from us faster than near objects. Obviously that takes energy. Dark energy is just a place holder name for that energy given we don't have a clue what it is or where it comes from. A black hole is a name for enormously heavy, small (smaller than the schwartz radius) and very dark objects whose existence is inferred from the their gravitational effects. They are found at the centre of galaxies, among other places.

guscost 8y ago

I would not be surprised if someday more than one of your first four questions are all resolved by the discovery that theoreticians have made a bad assumption, and have been chasing today’s phlogiston or aether. This might coincide with the discovery of a new theory answering (or proving unanswerable) the fifth question as well. Or, all the necessary “fixes” to the Standard Model are out there. Either way, I agree that it might be another long wait before our technology can find meaningful new constraints.

DiabloD3 8y ago

More to the point, the LHC has not answered the following questions: were we correct in thinking dark matter and dark energy exist (ie, physics did not accidentally mistake the map for the territory), that we were correct in thinking black holes actually do exist (and it isn't an entirely different phenomenon involving extremely high energy plasmoids or something even weirder), and that the big bang actually happened (and that the universe is indeed expanding).

codethief 8y ago
You can formulate all kinds of questions a given experiment like the LHC didn't answer but unless the experiment actually set out to answer these questions in the first place, you're mostly just talking about the empty set. Namely, the LHC was never directly concerned with black holes, the Big Bang, dark energy and dark matter. (Outside of the possibility that completely new physics would be found and that this would somehow lead to an explanation of dark matter, dark energy and/or quantum gravity down the road.) Moreover, I'm also not sure why you're casting doubt on dark energy (= the cosmological constant), the Big Bang and black holes. There are certainly many aspects about them we don't fully understand yet but their existence is generally not disputed.

cygx 8y ago

what is dark matter (the stuff which makes up 97% of the universe!) That's a ballpark figure for dark energy + dark matter combined.

iamgopal 8y ago

I was even hoping for big bang created again inside LHC.

akvadrako 8y ago
Maybe it happened, but it created another universe and we never noticed.
- zyxzevn 8y ago
  Maybe .. the other universe also contained life and sentient beings. But as they were aggressive and tried to invade our world. So the scientists decided to stop the experiment and never to tell anyone about it.

User23 8y ago

> The Standard Model has nothing to say on these, it is fundamentally incomplete. I fear we won't answer these questions within my lifetime, sure, we may get tantalising hints from astronomy, but not direct observation in experiment. One of my coworkers is a trained particle physicist, and he will be the first to say that the standard model is a mess and nobody in the field actually believes it's correct, just that it's what they currently have to work with. He describes it as basically a switch statement depending on the field in question. None of this is meant to denigrate the endeavor, it's just that nuclear physics makes electrodynamics look like child's play.