4 ms·

I imagine they can't improve upon the standard model if everything they find never contradicts what they already know. Or rather what they can already conclude

I imagine they can't improve upon the standard model if everything they find never contradicts what they already know. Or rather what they can already conclude by the standard model.

k__ 8y ago
Are there so many parts that could be wrong?
- proaralyst 8y ago
  Crucially: it really doesn't work with gravity or relativity.
  - jcranmer 8y ago
    The standard model incorporates special relativity, but you're right in that general relativity doesn't mesh with the standard model.
  - danbruc 8y ago
    To avoid confusion, relativity must be read as general relativity, the standard model is a relativistic quantum field theory and hence takes special relativity into account.
    - evanb 8y ago
      You can even formulate the standard model on a curved background metric that arises from GR. Just don't try to make the metric itself dynamical.
- chriswarbo 8y ago
  As well as ignoring gravity, the standard model also doesn't predict or explain any of those observations labelled "dark matter" and "dark energy". We can add an extra parameter to general relativity (known as the "cosmological constant") to describe "dark energy" observations via a kind of 'anti gravity'; although we still don't fully understand what that means, or whether it's a correct description. It's also unclear whether this would have anything to do with quantum theories (like the standard model). General relativity can explain "dark matter" observations by assuming there is more mass/matter than we can see (i.e. it's electrically neutral and doesn't interact with light). Since the standard model tries to describe all of the fundamental constituents of matter, and forces including electromagnetism (light), having nothing to say about such a seemingly large amount of stuff is a rather large discrepancy in the standard model. AFAIK the standard model also says that neutrinos have zero mass; yet we've observed them undergoing radioactive decay ("neutrino oscillation", where each sort of neutrino can decay into the others). Particles which decay require some amount of time to do so. Particles with zero mass always travel at the speed of light (like photons, and hypothetical gravitons) and hence don't experience any time passing (this sentence is a consequence of special relativity). So particles with zero mass can't decay, so neutrinos can't have zero mass. I don't think we've measured their mass very accurately yet; we know it's very small, but it cannot be zero.
- nategri 8y ago
  A big one is that the SM straight up does not account for neutrino mass, which we know they must have due to oscillations in flavor from sources such as the Sun. [1] [1] https://en.wikipedia.org/wiki/Solar_neutrino_problem https://en.wikipedia.org/wiki/Solar_neutrino_problem OOPS: I see a sibling comment also covers this. Oh well, I'll keep this one up since it's slightly more eye-catching.

I imagine they can't improve upon the standard model if everything they find never contradicts what they already know. Or rather what they can already conclude by the standard model.

k__ 8y ago

Are there so many parts that could be wrong?

proaralyst 8y ago
Crucially: it really doesn't work with gravity or relativity.
- jcranmer 8y ago
  The standard model incorporates special relativity, but you're right in that general relativity doesn't mesh with the standard model.
- danbruc 8y ago
  To avoid confusion, relativity must be read as general relativity, the standard model is a relativistic quantum field theory and hence takes special relativity into account.
  - evanb 8y ago
    You can even formulate the standard model on a curved background metric that arises from GR. Just don't try to make the metric itself dynamical.
chriswarbo 8y ago
As well as ignoring gravity, the standard model also doesn't predict or explain any of those observations labelled "dark matter" and "dark energy". We can add an extra parameter to general relativity (known as the "cosmological constant") to describe "dark energy" observations via a kind of 'anti gravity'; although we still don't fully understand what that means, or whether it's a correct description. It's also unclear whether this would have anything to do with quantum theories (like the standard model). General relativity can explain "dark matter" observations by assuming there is more mass/matter than we can see (i.e. it's electrically neutral and doesn't interact with light). Since the standard model tries to describe all of the fundamental constituents of matter, and forces including electromagnetism (light), having nothing to say about such a seemingly large amount of stuff is a rather large discrepancy in the standard model. AFAIK the standard model also says that neutrinos have zero mass; yet we've observed them undergoing radioactive decay ("neutrino oscillation", where each sort of neutrino can decay into the others). Particles which decay require some amount of time to do so. Particles with zero mass always travel at the speed of light (like photons, and hypothetical gravitons) and hence don't experience any time passing (this sentence is a consequence of special relativity). So particles with zero mass can't decay, so neutrinos can't have zero mass. I don't think we've measured their mass very accurately yet; we know it's very small, but it cannot be zero.
nategri 8y ago
A big one is that the SM straight up does not account for neutrino mass, which we know they must have due to oscillations in flavor from sources such as the Sun. [1] [1] https://en.wikipedia.org/wiki/Solar_neutrino_problem https://en.wikipedia.org/wiki/Solar_neutrino_problem OOPS: I see a sibling comment also covers this. Oh well, I'll keep this one up since it's slightly more eye-catching.