3 ms·

What kind of haste are we talking about here? Is it nanoseconds, or even faster?

at_a_remove 4y ago
Depends entirely on the particle. A free neutron might have a half life of around twenty minutes. These pentaquark particles, well, nanoseconds are too long to describe, by about ten orders of magnitude. Some of the heavy elements assembled in colliders are described as decaying so quickly that one side of the nucleus is coming together even as the other side is disintegrating, a sort of brief wave of existence traveling at nearly the speed of light across this thing that has been forced together and wants to fly apart.
kibwen 4y ago
Well, technically yes. 0.0000000000001 nanoseconds, to be semi-precise. :P (Or at least, that's the magnitude of a Higgs boson decay, about 160 yoctoseconds.)
- H8crilA 4y ago
  Lol, that's a lot faster than I thought. To save some googling: about 10^-22 seconds for a Higgs boson decay. Whe a nanosecond, one tick in a 1GHz clock, is 10^-9 seconds.
shagie 4y ago
An example of something considered to be "slow" is the muon. You could kind of thinking of it as a heavy electron (though that hand waves away a lot). It has a mean lifetime of 2.2 μs - which is fairly slow. Also note that they're not rare and there's a fair bit of neat science behind that too. > About 10,000 muons reach every square meter of the earth's surface a minute (from https://www.scientificamerican.com/article/muons-for-peace/ https://www.scientificamerican.com/article/muons-for-peace/ ). There's also neat stuff with time dilation and muons ( http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/muon.html http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/muon.html ) - there should be far fewer observed muons at the surface if muons didn't experience time dilation from their relativistic speeds. > The historical experiment upon which the model muon experiment is based was performed by Rossi and Hall in 1941. They measured the flux of muons at a location on Mt Washington in New Hampshire at about 2000 m altitude and also at the base of the mountain. They found the ratio of the muon flux was 1.4, whereas the ratio should have been about 22 even if the muons were traveling at the speed of light, using the muon half-life of 1.56 microseconds. When the time dilation relationship was applied, the result could be explained if the muons were traveling at 0.994 c. (note: mean lifetime and half-life are different numbers) The thing here is that 2.2 μs is slow, but even with something that is that fast (on a human scale), there's a lot of neat science that can be done with them. They've even made muonic atoms (where the electron is replaced by a muon) https://en.wikipedia.org/wiki/Exotic_atom https://en.wikipedia.org/wiki/Exotic_atom ... and that leads to possibilities on lowering fusion temperature ( https://en.wikipedia.org/wiki/Muon-catalyzed_fusion https://en.wikipedia.org/wiki/Muon-catalyzed_fusion ) because the muon is much closer to the nucleus in its ground state.

Depends entirely on the particle. A free neutron might have a half life of around twenty minutes. These pentaquark particles, well, nanoseconds are too long to describe, by about ten orders of magnitude. Some of the heavy elements assembled in colliders are described as decaying so quickly that one side of the nucleus is coming together even as the other side is disintegrating, a sort of brief wave of existence traveling at nearly the speed of light across this thing that has been forced together and wants to fly apart.

kibwen 4y ago

Well, technically yes. 0.0000000000001 nanoseconds, to be semi-precise. :P (Or at least, that's the magnitude of a Higgs boson decay, about 160 yoctoseconds.)

H8crilA 4y ago
Lol, that's a lot faster than I thought. To save some googling: about 10^-22 seconds for a Higgs boson decay. Whe a nanosecond, one tick in a 1GHz clock, is 10^-9 seconds.

shagie 4y ago

An example of something considered to be "slow" is the muon. You could kind of thinking of it as a heavy electron (though that hand waves away a lot). It has a mean lifetime of 2.2 μs - which is fairly slow. Also note that they're not rare and there's a fair bit of neat science behind that too. > About 10,000 muons reach every square meter of the earth's surface a minute (from https://www.scientificamerican.com/article/muons-for-peace/ https://www.scientificamerican.com/article/muons-for-peace/ ). There's also neat stuff with time dilation and muons ( http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/muon.html http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/muon.html ) - there should be far fewer observed muons at the surface if muons didn't experience time dilation from their relativistic speeds. > The historical experiment upon which the model muon experiment is based was performed by Rossi and Hall in 1941. They measured the flux of muons at a location on Mt Washington in New Hampshire at about 2000 m altitude and also at the base of the mountain. They found the ratio of the muon flux was 1.4, whereas the ratio should have been about 22 even if the muons were traveling at the speed of light, using the muon half-life of 1.56 microseconds. When the time dilation relationship was applied, the result could be explained if the muons were traveling at 0.994 c. (note: mean lifetime and half-life are different numbers) The thing here is that 2.2 μs is slow, but even with something that is that fast (on a human scale), there's a lot of neat science that can be done with them. They've even made muonic atoms (where the electron is replaced by a muon) https://en.wikipedia.org/wiki/Exotic_atom https://en.wikipedia.org/wiki/Exotic_atom ... and that leads to possibilities on lowering fusion temperature ( https://en.wikipedia.org/wiki/Muon-catalyzed_fusion https://en.wikipedia.org/wiki/Muon-catalyzed_fusion ) because the muon is much closer to the nucleus in its ground state.