- #1
Alex299792458
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I know that all the quark names have a meaning and that the strange quark was named "strange quark" because it had strange properties.What are those strange properties the strange quark possess?
In summary: Charmness acquired a strangeness of minus two, and anti-charmness plus two, and so on.In summary, the strange quark was named "strange quark" because of its strange properties, which were discovered when hadrons containing them were first observed. These properties were not in line with the existing framework for particles, and a new quantum number called "strangeness" was created to explain them.Later, the concept of quarks was introduced and the strange quark was one of the original three. It was found that the strange quark could only change into a down quark through the weak interaction, which explained the longer lifetimes of strange particles.Subsequently, the charm and bottom quarks were discovered, and
- #2
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They were strange to physicists of the time when hadrons containing them were discovered. This was mainly due to such hadrons not conforming to the isospin framework in the same way as earlier hadrons had. Such hadrons were strange and associated with a quantum number called "strangeness". Quarks were discovered later if I do not misremember, and strangeness turned out to be the number of strange quarks in the hadron (so named because of this).
- #3
jtbell
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IIRC, the first-discovered strange particles (what we know now as the K and Λ) have much longer lifetimes than they "should" have had.
- #4
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Right, thanks for the reminder.jtbell said:
Naturally, this is now attributed to weak interactions being the only interaction which breaks quark flavour.
- #5
Alex299792458
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Thanks for clearing up for me because a website I used for a long time said that they where named strange quarks because they where smaller the higher generation quarks(up quark) but they where more massive which is true for all the other 3 quarks and if there where more quarks they would be even smaller than a top quark but more massive than all 6 quarks combined. So if that answer for why the strange quark are called strange then all the other quarks would also be called strange quarks and those third generation quarks would be even stranger due to their unfathomable size and there unfathomable mass for a particle. Particularly the top with a size of 1 x 10e-22 meters vs. an up quark with 1 x 10e-18 meters and 173 GeV with more than 100,000 times the mass of a up quark so it would be much stranger than a strange quark with only 50 times the mass of a up quark and a size of 4 x 10e-18.
- #6
jtbell
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The concept of "strangeness" came before the idea of the strange quark. In the early 1950s some newly-discovered particles had longer lifetimes than expected, so they were called "strange" and a new quantum number, "strangeness", was invented for them. The strong and electromagnetic interactions conserve strangeness, but the weak interaction doesn't.
In the 1960s the idea of quarks came along. Originally there were only three of them: up, down and strange. All the "strange" particles have a strange quark in them, and a strange quark can convert to a down quark only via the weak interaction, which explains the long lifetime of "strange" particles.
The charm and bottom (originally "beauty") quarks came along later, in the 1970s, to explain more newly-created particles that have properties that don't fit into the old up-down-strange scheme.
Finally, based on the pattern formed by the up, down, strange, charm and bottom quarks, it was widely assumed that a "top" quark also had to exist, but particles containing top quarks weren't actually observed until the 1990s.
In the meantime some physicists speculated that maybe top quarks weren't really necessary after all. I remember seeing in the early 1980s, towards the end of my graduate-school period, preprints about "topless bottom models" which sounded a bit, um, risqué.
In the 1960s the idea of quarks came along. Originally there were only three of them: up, down and strange. All the "strange" particles have a strange quark in them, and a strange quark can convert to a down quark only via the weak interaction, which explains the long lifetime of "strange" particles.
The charm and bottom (originally "beauty") quarks came along later, in the 1970s, to explain more newly-created particles that have properties that don't fit into the old up-down-strange scheme.
Finally, based on the pattern formed by the up, down, strange, charm and bottom quarks, it was widely assumed that a "top" quark also had to exist, but particles containing top quarks weren't actually observed until the 1990s.
In the meantime some physicists speculated that maybe top quarks weren't really necessary after all. I remember seeing in the early 1980s, towards the end of my graduate-school period, preprints about "topless bottom models" which sounded a bit, um, risqué.
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- #7
Alex299792458
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How long did those strange particles last?
- #8
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Just a wordog warning: Quarks (as well as other elementary particles) do not have an intrinsic size. Be very suspicious of any source which claims otherwise.
You can check the lifetimes of all these particles at http://pdg.lbl.gov/
You can check the lifetimes of all these particles at http://pdg.lbl.gov/
- #9
mfb
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That does not make sense at all.Alex299792458 said:
By the way: due to a historic accident (see above), strange-quarks have a strangeness of minus one, and anti-strange-quarks have a strangeness of plus one.
1. What is a strange quark?
A strange quark is a subatomic particle that is one of the six types of quarks, which are fundamental building blocks of matter. It is distinguished by its characteristics, including its electric charge, spin, and mass.
2. Why are strange quarks called "strange"?
The term "strange" was given to this type of quark because it was initially found to have unusual properties that did not fit with the known laws of physics at the time. However, it is now understood that these properties are a result of the strange quark's high mass and relatively long lifetime.
3. How are strange quarks different from other types of quarks?
Strange quarks differ from other types of quarks in their mass and lifetime. They are also the only type of quark that can decay into lighter quarks, making them important in the study of particle physics and the structure of matter.
4. What is the role of strange quarks in the Standard Model of particle physics?
The Standard Model of particle physics is a theory that describes the fundamental particles and forces that make up the universe. In this model, strange quarks play a crucial role in the formation of hadrons, such as protons and neutrons, which are the building blocks of atomic nuclei.
5. How are strange quarks studied in experiments?
Scientists study strange quarks using high-energy particle accelerators, such as the Large Hadron Collider (LHC). By colliding particles at high speeds, they can observe the behavior of strange quarks and their interactions with other particles, providing valuable insights into the fundamental laws of nature.
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