Spectacularly interesting!! I just discovered this series today and I want to watch every single episode!! I am currently reading a cosmology book (Japanese book, sorry, I currently work in Japan!) and this episode fills a lot of gaps I didn't fully understand on the book. Thanks a billion!!!
I'm mildly confused here... 1: A neutron is comprised of 2 * Down-quarks and 1 * Up-quark A Down-quark has a mass of about 4.8 MeV/c*c An Up-quark has a mass of about 2.2 MeV/c*c However, the neutron has a reported mass of around 939.57 MeV/c*c 2: A Proton is comprised of 1 * Down-quark and 2 * Up-quarks However the proton has a reported mass of around 938.28 MeV/c*c I suspect that the trailing speed of light squared term (c*c) is somehow doing my head in??? i.e. A neutron is somehow not 4.8+4.8+2.2 = 11.8 MeV/c*c My head hurts!!!
You are chatting about rest mass and not talking into account the binding energy. This is the energy lost due to falling into the potential well of the strong nuclear force.
WOW!!! I didn't expect a response from THE man himself!!! Thanx heaps Jason!!! The figures in my example (along with your response) has really helped to illustrate to me how STRONG the nuclear strong force actually is!!! (The ratio of the aggregated rest-masses of the individual quarks comprising a neutron versus the actual neutron itself spans orders of magnitude!)
a posh duck for mister muck - i know, i know but i watched astrum the other week and he described the pre-cambrian as earth in its 'salad days'. to me that just proves shakespeare's plays were penned by francis bacon and aided also, by the earl of sandwich - salad days is coded reference to that heavenly classic - the blt. 🥪😉😋
On the quark excess at freeze-out. You know how the expectation values for heads and tails, when you toss a coin 1000 times, is 500 instances for each side landing up? In practice, it hardly ever works out that way. You'll get something like 505 heads and 495 tails, or 488 heads and 512 tails, etcetera. Well, the early universe probably had some little black holes floating around that gobbled up both quarks and antiquarks, both electrons and positrons. Statistically, you'd expect that the same numbers of particles and of antiparticles would get removed from circulation by the black holes, but there's again some sloppiness in what actually happens. So you ended up with more quarks than antiquarks, and more electrons than positrons, and when all the annihilating was done the leftover stuff was matter and the antimatter was mostly gone.
That's only if you happen to have a perfectly balanced coin for the most part the heads is actually heavier so Tails is slightly more likely to up (American coins)
That analogy doesn't really work to explain the prevalence of matter vs. anti-matter. Flipping a coin a couple hundred times produces a relatively pretty wide standard deviation in the ratio of results vs. the number of flips, because it's a low number of trials. If you do it a *whole lot*, though, you will reduce the granularity of each trial, and when you do, you can see the bell curve of the expected results get narrower and narrower until it's almost completely convergent at 1:1 for huge numbers of trials. The universe is estimated to have something like 10^300 particles of matter. That's an incredibly huge number of trials. If it was really perfect 50-50 odds, at such a huge number of trials, the results would be extremely close to a perfect 1:1 ratio and most likely there would be so little matter in the universe that whatever traces are left wouldn't even be worth mentioning. But that's not what happened, instead we have a universe filled with stars and galaxies. Exactly symmetric odds don't favor that.
I don't understand neutrinos. I general principle of nature is that good emitters are good absorbers and bad emitters are bad absorbers. If you make an antenna that is very efficient at broadcasting at a certain frequency, it will be very efficient at acting as a receiving antenna at that frequency. If you have a black object, it will radiate proportionally more if it is itself hot, and in fact absorptivity=emissivity and that is required by the 2nd law of thermodynamics. SO, why then is it the case that neutrinos are SO EASILY emitted by atomic nuclei, but it is so difficult for them to absorb them? It's the only thing that violates this principle that I know of, that good emitters are good absorbers. It's nearly IMPOSSIBLE to absorb a neutrino, but every time a neutron turns into a proton or vice versa, which it does easily in a radioactive isotope, and a neutron on its own has a half life of about 10 minutes, but every time a neutron turns into a proton or vice versa, it emits a neutrino. But then that neutrino hits an atomic nucleus and it goes right through it almost 100% of the time.
Your general principle you start with applies mostly to light, and then to things with high opacity and mostly only to Blackbodies. A good analogy for neutrinos is a putting green on a golf course. If it’s a perfect absorber, then the hole into which you putt will be the size of a stadium. All golf balls go in. But for neutrinos, the joke you’re aiming for is so tiny that your chance of hitting it is really small. And all we need to do is hit the hole, but even sink it. Pretend our hole is a specific atom, or, more explicitly, the space in between two protons in the nucleus of an atom. Basically the target is very very small.
I love these videos and this is the first one that I've seen that actually helps me understand the BB theory in depth. I am confused about the timeline and expansion though, which is probably wholly due to my layman's understanding of the processes at play. If the hadrons came into existence from Quarks at one microsecond, that means that the universe could have only been about 3/8ths of a mile in diameter, because the light travels at about 1 foot per nanosecond and nothing can travel faster than light. Right? How would that not cause an immediate creation of a black hole? Was matter somehow able to expand faster than light in order to blow past the (huge!) Schwarzschild radius of a universe worth of matter compressed into a ball 2000' wide? And, how could all that matter fit into such a small space? The only thing that makes sense to me is that matter and photons must have been able to travel much faster than it does now, which is probably very wrong because that means the speed of light is inverse to the size of the universe . Like I said, I am so confused and can't wrap my head around this.
The nature of “big” is interesting here. The universe didn’t have an edge, it had a horizon. Likely outside the horizon the universe was likely non-finite or really close to that.
Please see the updated version of this video here: ruclips.net/p/PLyu4Fovbph6dSGHJOP3o171TON6rLyN6w
this is the most significant video I have ever watched!!! (a nice indication of the importance of cosmology)
of dozens or more youtubes on the topic to which I have listened, this is the best content, and so beautifully presented, thanks a lot!
Spectacularly interesting!! I just discovered this series today and I want to watch every single episode!! I am currently reading a cosmology book (Japanese book, sorry, I currently work in Japan!) and this episode fills a lot of gaps I didn't fully understand on the book. Thanks a billion!!!
You should look at my playlist for the Full College Course. That'll do what you want...
Just found you Mr. Kendall. You speak so easily! No errrrrs or ahhh or uhhhs !! I love listening to geniuses and you rock !
Love these lectures!! So grateful you did them and I hope they stay on RUclips forever for others to download and enjoy
Thanks a bunch. I wasn't aware of all the confirmation demonstrated here.
I love the thumbnail. The idea of and desire to look outside of my own existence has always inspired me!
Thank you 😊 💓 for the best content on you tube thank you for takeing the time for us it helps all science 👍 😀 move forward at the speed of lite
FYI the term "quark" seems to be from part of the James Joyce novel Finnegans Wake.
en.wikipedia.org/wiki/Quark#Etymology
How do you/they/we extrapolate back that the universe was tiny ? Why not the size of a basketball ?
How could everything "fit" into a tiny space ?
Thank you.
Another super interesting video. Much appreciated.
I'm mildly confused here...
1: A neutron is comprised of 2 * Down-quarks and 1 * Up-quark
A Down-quark has a mass of about 4.8 MeV/c*c
An Up-quark has a mass of about 2.2 MeV/c*c
However, the neutron has a reported mass of around 939.57 MeV/c*c
2: A Proton is comprised of 1 * Down-quark and 2 * Up-quarks
However the proton has a reported mass of around 938.28 MeV/c*c
I suspect that the trailing speed of light squared term (c*c) is somehow doing my head in???
i.e. A neutron is somehow not 4.8+4.8+2.2 = 11.8 MeV/c*c
My head hurts!!!
You are chatting about rest mass and not talking into account the binding energy. This is the energy lost due to falling into the potential well of the strong nuclear force.
WOW!!! I didn't expect a response from THE man himself!!! Thanx heaps Jason!!!
The figures in my example (along with your response) has really helped to illustrate to me how STRONG the nuclear strong force actually is!!!
(The ratio of the aggregated rest-masses of the individual quarks comprising a neutron versus the actual neutron itself spans orders of magnitude!)
a posh duck for mister muck - i know, i know but i watched astrum the other week and he described the pre-cambrian as earth in its 'salad days'. to me that just proves shakespeare's plays were penned by francis bacon and aided also, by the earl of sandwich - salad days is coded reference to that heavenly classic - the blt. 🥪😉😋
I like "Stir for one Microsecond". If I am in the mood, I might make some Quark Soup at some point.
I like the reference to the Woodie Allen movie.
On the quark excess at freeze-out. You know how the expectation values for heads and tails, when you toss a coin 1000 times, is 500 instances for each side landing up? In practice, it hardly ever works out that way. You'll get something like 505 heads and 495 tails, or 488 heads and 512 tails, etcetera. Well, the early universe probably had some little black holes floating around that gobbled up both quarks and antiquarks, both electrons and positrons. Statistically, you'd expect that the same numbers of particles and of antiparticles would get removed from circulation by the black holes, but there's again some sloppiness in what actually happens. So you ended up with more quarks than antiquarks, and more electrons than positrons, and when all the annihilating was done the leftover stuff was matter and the antimatter was mostly gone.
That's only if you happen to have a perfectly balanced coin for the most part the heads is actually heavier so Tails is slightly more likely to up (American coins)
That analogy doesn't really work to explain the prevalence of matter vs. anti-matter. Flipping a coin a couple hundred times produces a relatively pretty wide standard deviation in the ratio of results vs. the number of flips, because it's a low number of trials. If you do it a *whole lot*, though, you will reduce the granularity of each trial, and when you do, you can see the bell curve of the expected results get narrower and narrower until it's almost completely convergent at 1:1 for huge numbers of trials. The universe is estimated to have something like 10^300 particles of matter.
That's an incredibly huge number of trials.
If it was really perfect 50-50 odds, at such a huge number of trials, the results would be extremely close to a perfect 1:1 ratio and most likely there would be so little matter in the universe that whatever traces are left wouldn't even be worth mentioning. But that's not what happened, instead we have a universe filled with stars and galaxies. Exactly symmetric odds don't favor that.
A 53 minutes long video about the first 3 minutes of the Universe.
Takes a lot of words, doesn't it?
I don't understand neutrinos. I general principle of nature is that good emitters are good absorbers and bad emitters are bad absorbers. If you make an antenna that is very efficient at broadcasting at a certain frequency, it will be very efficient at acting as a receiving antenna at that frequency. If you have a black object, it will radiate proportionally more if it is itself hot, and in fact absorptivity=emissivity and that is required by the 2nd law of thermodynamics. SO, why then is it the case that neutrinos are SO EASILY emitted by atomic nuclei, but it is so difficult for them to absorb them? It's the only thing that violates this principle that I know of, that good emitters are good absorbers. It's nearly IMPOSSIBLE to absorb a neutrino, but every time a neutron turns into a proton or vice versa, which it does easily in a radioactive isotope, and a neutron on its own has a half life of about 10 minutes, but every time a neutron turns into a proton or vice versa, it emits a neutrino. But then that neutrino hits an atomic nucleus and it goes right through it almost 100% of the time.
Your general principle you start with applies mostly to light, and then to things with high opacity and mostly only to Blackbodies. A good analogy for neutrinos is a putting green on a golf course. If it’s a perfect absorber, then the hole into which you putt will be the size of a stadium. All golf balls go in. But for neutrinos, the joke you’re aiming for is so tiny that your chance of hitting it is really small. And all we need to do is hit the hole, but even sink it. Pretend our hole is a specific atom, or, more explicitly, the space in between two protons in the nucleus of an atom.
Basically the target is very very small.
I love these videos and this is the first one that I've seen that actually helps me understand the BB theory in depth. I am confused about the timeline and expansion though, which is probably wholly due to my layman's understanding of the processes at play.
If the hadrons came into existence from Quarks at one microsecond, that means that the universe could have only been about 3/8ths of a mile in diameter, because the light travels at about 1 foot per nanosecond and nothing can travel faster than light. Right? How would that not cause an immediate creation of a black hole? Was matter somehow able to expand faster than light in order to blow past the (huge!) Schwarzschild radius of a universe worth of matter compressed into a ball 2000' wide? And, how could all that matter fit into such a small space?
The only thing that makes sense to me is that matter and photons must have been able to travel much faster than it does now, which is probably very wrong because that means the speed of light is inverse to the size of the universe . Like I said, I am so confused and can't wrap my head around this.
The nature of “big” is interesting here. The universe didn’t have an edge, it had a horizon. Likely outside the horizon the universe was likely non-finite or really close to that.
Careful, quark shaves the latinum.