World's largest particle accelerator built by the CERN (European Organization for Nuclear Research) on the Franco-Swiss border near Geneva, Switzerland. It is designed to collide beams of protons with a centre of mass energy of up to 14 TeV. It contains the large detectors ALICE, ATLAS, CMS and LHCb.
Questions tagged [large-hadron-collider]
444 questions
70
votes
5 answers
How do we know the LHC results are robust?
Nature article on reproducibility in science.
According to that article, a (surprisingly) large number of experiments aren't reproducible, or at least there have been failed attempted reproductions. In one of the figures, it's said that 70% of…
Allure
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66
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5 answers
Why isn’t CERN afraid of a fusion reaction in the LHC?
Given that they can reach terrifying energies and temperatures, why isn’t fusion of protons a concern? After all, they start with a plasma and ram protons into each other.
At some point the strong force will overcome the proton-proton electric…
aquagremlin
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51
votes
4 answers
Why does LIGO do blind data injections but not the LHC?
The LIGO group has a team that periodically produces fake data indicating a possible gravitational wave without informing the analysts. A friend of mine who works on LHC data analysis told me that none of the LHC groups do this. Why does one of…
tparker
- 51,104
50
votes
4 answers
What if the LHC doesn't see SUSY?
A question in four parts.
What are the main problems which supersymmetry purports to solve?
What would constitute lack of evidence for SUSY at the proposed LHC energy scales (e.g. certain predicted superpartners are not in fact observed)?
Are…
Nigel Seel
- 3,394
44
votes
3 answers
Why is 7 TeV considered as a big amount of energy?
Considering that $7$ TeV is more or less the same kinetic energy as a mosquito flying, why is it considered to be a great amount of energy at the LHC?
I mean, a giant particle accelerator that can only provide 7 TeV of energy? (14 in the mass…
EXVII
- 3,783
42
votes
4 answers
Will the Large Hadron Collider "explode" if the power is turned up too high?
The Large Hadron Collider, at low power, accelerates particles such that much of the total energy provided goes towards increasing their kinetic energy and their masses increase to some extent as well, and so Newton's equations are valid for this…
Michael Lee
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37
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3 answers
What is the current status of string theory (2013)?
I've seen a bunch of articles talking about how new findings from the LHC seem to disprove (super)string theory and/or supersymmetry, or at least force physicists to reformulate them and change essential predictions.
Some examples:
Did the Large…
aditsu
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34
votes
5 answers
What does CERN do with its electrons?
So to get a proton beam for the LHC, CERN prob has to make a plasma and siphon off the moving protons with a magnet. Are the electrons stored somewhere? How? I don’t mean to sound stupid but when they turn off the LHC, all those protons are going to…
aquagremlin
- 1,729
29
votes
3 answers
How can an electron fake a jet?
This is a question for experimentalists. I have seen in several ATLAS papers (see for example chapter 4 in arXiv:1602.09058, 6th paragraph), that after objects have been correctly identified, any jet close enough to a candidate electron is removed…
Dar
- 1,053
27
votes
5 answers
Is a proton collision (collisions like in the LHC) visible to the human eye?
I was curious if a proton collision is visible to the human eye.
(This might sound like a really basic question and forgive me if it is. I am very inexperienced in Physics and just wanted an answer to my curiosity)
Reagan
- 279
23
votes
2 answers
Why can't the LHC detect heavy particles?
I am reading The Elegant Universe by Brian Greene.
In many places it's directly/indirectly mentioned that the LHC may not be able to detect (with the current technology) heavy particles to prove Super-Symmetry.
What prevents such accelerators from…
Inquisitive
- 522
21
votes
1 answer
What news about the second Higgs mode (or the mysterious particle) is anticipated to be seen at LHC around 750 GeV?
A few months ago, there were press releases about a possible second Higgs mode unveiled by LHC experiments. Or perhaps a new particle even more surprising like a graviton ... There was no certainty about this new particle because experiments didn't…
FraSchelle
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21
votes
4 answers
If the LHC-calculated mass of the Higgs is wrong, how long will it take to determine this with confidence?
After I watched "Particle Fever"--the movie about Large Hadron Collider (LHC) and the successful identification of the Higgs boson--I became a bit concerned with that team's handling of various negative PR incidents. Further, with the amount of…
21
votes
4 answers
Why doesn't the LHC accelerate electrons?
Electrons
have a much bigger charge density as the protons (and especially lead nuclei),
aren't compound particles as the protons (and especially lead nuclei)
are able to get a much bigger energy with the same fields as the protons (and especially…
peterh
- 8,872
19
votes
2 answers
Why is Higgs particle detected much later than top quark when it's lighter?
The Higgs boson is lighter than the top quark. But the top quark was discovered in the mid-1990s where the Higgs boson escaped detection for two more decades. So if the energy has already been achieved to produce Higgs boson, why did it escape…
SRS
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