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right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
so this is now 100 million light years away from each other . the universe is expanding . these coordinates , the space is actually spreading out .
could the universe be expanding faster than the speed of light ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
ok , this photon says , oh , in another -- let me write this . this is 80 million light years -- in another 40 million light years , maybe i 'm going to get over here . but the reality is over that next 40 million light years -- sorry , in 40 million years , i might get right over here , because this is 80 million ligh...
if the universe works the way you say it does then either you are saying that the sped of light get faster over time , is this correct ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and in fact , i 'll just make that roughly -- i wo n't make it the center just because i think it makes it easier to visualize if it 's not the center . and let 's say at that very early stage in the universe , if you were able to just take some rulers instantaneously and measure that , you would measure this distance ...
is there anany other way to measure the universe or distance between planets ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
now , what i 'm going to hesitate to do , because we 're talking over such large distances and we 're talking on such large time scales and time scales over which space itself is expanding -- we 're going to see in this video that you can not say that this object over here , this is not necessarily , this is not , i 'l...
if someone could invent such a detection device we would surely know much more ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
now , what i 'm going to hesitate to do , because we 're talking over such large distances and we 're talking on such large time scales and time scales over which space itself is expanding -- we 're going to see in this video that you can not say that this object over here , this is not necessarily , this is not , i 'l...
when he is talking about cosmological time and `` primitive states '' , could n't we relate that to alien life forms ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
it is like , wow , i was able to cover 20 million light years in only 10 million years . it looks like i 'm moving faster than the speed of light . the reality is it 's not because the space coordinates themselves are spreading out .
does the universe expand at a rate faster than the speed of light ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and that photon is traveling at the speed of light . it is light . and so that photon , says , you know what , i only got 30 million light years to travel .
is the light of big bang travelling in the space still ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
10 million years go by . the universe has expanded . this coordinate , where we 're sitting today at the present time , is now all the way over here .
sal said unless there is something weird going on we should be able to observe the universe in any direction and `` see '' about the same distance in all directions ... how can we know that in the big picture of things , our solar system and planet is not on the `` edge '' of the universe ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
if i 'm drawing the whole observable universe , the center actually should be where we are . because we can observe an equal distance . if things are n't really strange , we can observe an equal distance in any direction . so actually maybe we should put us at the center .
and , if this is so , does that mean that the coordinates for other objects we observe would be really different in terms of distance relative to their placement in the universe from the big bang ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
it is like , wow , i was able to cover 20 million light years in only 10 million years . it looks like i 'm moving faster than the speed of light . the reality is it 's not because the space coordinates themselves are spreading out .
would the universe be technically moving faster than light ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
all the coordinates have gotten further away from each other . now , what just happened here ? the universe has expanded .
was there anything inside the singularity where the `` big bang '' happened ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and we 'll see that that was the range that it was emitting in . but it emits a photon . and that photon is traveling at the speed of light . it is light .
the opening space in between the photon and the initial body is faster than the speed of light ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and i want to make it very clear . this object is now 46 billion light years away from us . when we just use light to observe it , it looks like , just based on light years , hey , this light has been traveling 13.7 billion years to reach us . that 's our only way of kind with light to kind of think about the distance ...
how does any light reach anywhere else if every thing else is expanding away ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
so let 's go 300,000 years after that initial expansion of that singularity . so we 're just 300,000 years into the universe 's history right now . so this is roughly 300,000 years into the universe 's life . i guess we could view it that way . and first of all , at that point things have n't differentiated in a meanin...
would this not make a lot more sense if viewed from a view point where god created the universe in one day approximately 6,000 years ago ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and we 'll see that that was the range that it was emitting in . but it emits a photon . and that photon is traveling at the speed of light . it is light . and so that photon , says , you know what , i only got 30 million light years to travel . that 's not too bad .
what is the difference between a photon reaching our eyes that is only one day old in comparison to a photon that is thousands of light years ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
so this is now 100 million light years away from each other . the universe is expanding . these coordinates , the space is actually spreading out .
do scientists know how fast the universe is expanding ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
so you ca n't just multiply a rate times time on these cosmological scales , especially when the coordinates themselves , the distance coordinates are actually moving away from each other . but i think you see , or maybe you might see , where this is going . ok , this photon says , oh , in another -- let me write this ...
put a probe on a planet close to ours and see how much the distance between them grows ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and we 'll see that that was the range that it was emitting in . but it emits a photon . and that photon is traveling at the speed of light . it is light .
if you say that while the photon is traveling , will it ever get there ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and in future videos , i 'm actually going to talk about the time scale . so we can really appreciate how long , or even start to appreciate , or appreciate that we ca n't appreciate how long 13.7 billion years is . and i also want to emphasize that this is the current best estimate .
how long until the sun burns out ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
but it emits a photon . and that photon is traveling at the speed of light . it is light .
speed of light is still more than the speed of expansion of universe ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when this occurred is 13.7 billion years ago . and even though we 're used to dealing with numbers in the billions , especially when we talk about large amounts of money an...
is its about 3.7 billion years ago how does the vibrations still exist ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
but the reality is after 40 million years -- so another 40 million years go by -- now , all of a sudden , the universe has expanded even more . i wo n't even draw the whole bubble . but the place where the photon was emitted from might be over here .
does n't all vibration s also die out even if it 's a big explosion ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
it is like , wow , i was able to cover 20 million light years in only 10 million years . it looks like i 'm moving faster than the speed of light . the reality is it 's not because the space coordinates themselves are spreading out .
if the universe is expanding at a faster and faster rate , will the rate of expansion eventually reach the speed of light ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
still on a cosmological time scale , still almost at kind of the infancy of the universe because we 're talking about 13.7 billion years . so let 's say 10 million years . 10 million years go by .
so if we are observing an object through photons that were emitted 3 million years ago , could we say ( from a scientific viewpoint ) that that object is 3 million years old because we have no way of knowing otherwise ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
10 million years go by . the universe has expanded . this coordinate , where we 're sitting today at the present time , is now all the way over here .
how many alaxys are in th universe ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
10 million years go by . the universe has expanded . this coordinate , where we 're sitting today at the present time , is now all the way over here .
how dos the universe `` end '' is there just a wall ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and now our current position is over here . where the light got after 10 million years is now over here . and now , where the light is after 40 million years , maybe it 's over here .
what was the temperature of the universe when the big bang occurred ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
10 million years go by . the universe has expanded . this coordinate , where we 're sitting today at the present time , is now all the way over here .
how big is the entire universe anyway ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and we 'll see that that was the range that it was emitting in . but it emits a photon . and that photon is traveling at the speed of light .
would not the photon have no concept of time ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and we 'll see that that was the range that it was emitting in . but it emits a photon . and that photon is traveling at the speed of light .
will that photon ever reach us ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
but the distance that it reversed , maybe this distance right here is now 20 million light years because it got there . every time it moved some distance , the space that it had traversed is now stretched . so even though its traveled for 10 million years , the space that it traversed is no longer just 10 million light...
what does `` traversed '' mean ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
so what we 're going to see is this white-hot haze . so we 're going to see this kind of white-hot plasma , white hot , undifferentiated not differentiated into proper stable atoms , much less stars and galaxies , but white hot . we 're going to see this white-hot plasma . the reality today is that point in space that ...
a question poped up : so without the expansion we would be able to see that white hot plasma ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
maybe now , it 's on the order of -- i do n't know -- maybe it 's a billion light years . maybe now it 's a billion light years . and maybe this distance over here -- and i 'm just making up these numbers .
and a few billion years ago every light could have been seen ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
so maybe it 's 13.4 or whatever -- i keep changing the decimal -- but 13.4 billion light years away . but the reality is if you had a ruler today , light year rulers , this space here has stretched so much that this is now 46 billion light years . and just to give you a hint of when we talk about the cosmic microwave b...
how much bigger is a light year than a mile ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
10 million years go by . the universe has expanded . this coordinate , where we 're sitting today at the present time , is now all the way over here .
is n't the other object not supposed to be in the ''visible universe '' ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
the longest that that could have been traveling is 13.7 billion years . so it could be traveling 13.7 billion years . so when we looked at that depiction -- this i think was two or three videos ago , of the observable universe -- i drew , it was this circle .
did n't sal say that the universe is closer to 13.8 billion years , not 13.7 billion years , in an earlier video ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
the other thing to think about is as this -- let me actually draw it . so let 's go 300,000 years after that initial expansion of that singularity . so we 're just 300,000 years into the universe 's history right now .
how was there a singularity when there was nothing ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
so this is now 100 million light years away from each other . the universe is expanding . these coordinates , the space is actually spreading out .
so if the `` surface area '' of our universe is expanding and all of this stuff is getting farther apart , does n't that mean out own atoms are getting farther apart ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and we 'll see that that was the range that it was emitting in . but it emits a photon . and that photon is traveling at the speed of light . it is light .
but if expansion were to move the celestial bodies with it , would n't the photon be moved as well , to the point where it 's not going light speed anymore ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
so this is now 100 million light years away from each other . the universe is expanding . these coordinates , the space is actually spreading out .
is there a point in time when the universe will stop expanding ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
and that photon is traveling at the speed of light . it is light . and so that photon , says , you know what , i only got 30 million light years to travel . that 's not too bad .
when a photon reaches our eyes , how do we know for sure how long ( how many light years ) it has traveled ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
but the light from that remote object is just now getting to us . and that light took 13.7 billion years to get to us . now , what i 'm going to hesitate to do , because we 're talking over such large distances and we 're talking on such large time scales and time scales over which space itself is expanding -- we 're g...
we do n't know how long the universe will be expanding but , say it was expanding infinitely , would light 13.7 billion years away ever reach us ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
but it emits a photon . and that photon is traveling at the speed of light . it is light .
why does light move at a constant speed ?
right now , the best estimate of when the big bang occurred -- and once again , i do n't like the term that much because it kind of implies some type of explosion . but what it really is is kind of an expansion of space , when space started to really start to expand from a singularity . but our best estimate of when th...
10 million years go by . the universe has expanded . this coordinate , where we 're sitting today at the present time , is now all the way over here .
did our universe come from the big bang ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
the $ 400 million senior tranche we raised from soon . 1000 senior securities , collateralized debt obligations . these are these , right here .
are collateralised debt obligations a pool of mortgage backed securities ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
so let 's see how we could use this same asset pool , the same pool of loans , and satisfy all of these people . satisfy this guy , who wants maybe a lower return but lower risk , and this guy , who 's willing to take a little bit higher risk in exchange for higher return . so now in this situation , we have the same b...
however the owners of the mbss all paid $ 1100 for their shares ; is n't your rate of return usually calculated compared to your investment , and therefore lower than 9 % ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
you 'd have to sell that loan to someone else . but if you have a mortgage-backed security , you can actually trade the security with someone else . and they might pay you , who knows , they might pay more than $ 1000 .
the mbs is priced based on the cfs from the mortgages , what would cause the security to trade at a premium ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
but like we said before , this security , in order to place a value on it , you have to do some type of analysis of what you think it 's worth . or what you think the real interest will be after you take into account people pre-paying their mortgage , people defaulting on their mortgage , and other things like short-te...
would it just be speculation given the number of mortgages in the pool having variable interest rates ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
so you 're saying , why would n't everyone want to be an equity investor ? well , let me ask you a question . what happens if -- let 's go to that scenario where we talked before -- 20 % of the borrowers just say , you know what ?
and as a side question to that , what motivation does the ib have to purchase these mortgages at anything more than par , back to the upside risk question , should n't the mortgager have to sell at a discount ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
and i know what you 're thinking . boy , sal , that sounds amazing . why would n't everyone want to be an equity investor ?
sal , one question which came to mind whilst watching these presentations on cdos and mbss is this : why do the commercial banks not engage in the practice of investment banking ( or merge with/acquire said investment bank ) , given that it seems to be very profitable ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
and they borrowed the money essentially from a special purpose entity . they borrowed it from their local mortgage broker , who then sold it to a bank , or to an investment bank , who created the special purpose entity , and then they ipo the special purpose entity and raise the money from people who bought the mortgag...
what happened to the bank when the spe ( ipo ) collapsed ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
of that $ 100 million in payments , 6 % on the $ 400 million , that 's $ 24 million in payments . right ? so $ 24 million in payments will go to the senior tranche .
and senior tranches to be affected , 33 % and 66 % default rates , respectively , would have to be achieved , right ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
so this is a form of a collateralized debt obligation . this is actually a mortgage-backed collateralized debt obligation . you can actually do this type of a structure with any type of debt obligation that 's backed by assets .
was one of the core problems of the credit bubble the very fact that traditionally `` illiquid '' assets ( mortgages ) became very liquid due to mortgage-backed securities and cdos ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
because it 's 10 % . $ 100 million in payments . of that $ 100 million in payments , 6 % on the $ 400 million , that 's $ 24 million in payments . right ?
so does n't the total interest received becomes $ 80 million ( $ 100mn - $ 20mn ) ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
this is actually a mortgage-backed collateralized debt obligation . you can actually do this type of a structure with any type of debt obligation that 's backed by assets . so we did the situation with mortgages , but you could do it with a bunch of assets .
is the type of grouping the only difference ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
and all of a sudden , these guys are not going to be cut off . this guy is still going to get $ 24 million , this guy is still going to get $ 21 million , but now this guy is going to get $ 45 million . but he 's still getting above average yield .
considering your last video , assume that there are 20 % borrowers default for whatever reason , would there only be $ 80m that the bank is going to get ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
and say that there 's another investor here , and he thinks that this is boring . you know , 9 % , 10 % . who cares about that ?
in reality , do you know during the 08 's crises how many people actually defaulted ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
so this is a form of a collateralized debt obligation . this is actually a mortgage-backed collateralized debt obligation . you can actually do this type of a structure with any type of debt obligation that 's backed by assets .
what effect does that have on the holders of these mortgage-backed securities ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
what happens if -- let 's go to that scenario where we talked before -- 20 % of the borrowers just say , you know what ? i ca n't pay this mortgage anymore . i 'm going to hand you back the keys to these houses .
if my 325k mortgage has a 7 % intrest , how can anyone get 16 % from that mortgage ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
but if you have a mortgage-backed security , you can actually trade the security with someone else . and they might pay you , who knows , they might pay more than $ 1000 . they might pay you less .
where does the money come from to pay investors ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
now let 's say it gets even worse . let 's say a bunch of borrowers start defaulting on their loans . and instead of getting $ 90 million per year , you start only getting $ 50 million in per year .
who sold the investment bank the loans already provided the loans to the borrowers ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
right ? so $ 24 million in payments will go to the senior tranche . similarly we issued 300,000 shares at $ 1000 per share on the mezzanine tranche . this is also 1000 .
and similarly , if housing prices increase , will the share price of the senior tranche be the first to increase ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
now let 's say it gets even worse . let 's say a bunch of borrowers start defaulting on their loans . and instead of getting $ 90 million per year , you start only getting $ 50 million in per year .
what happens to the principal of the defaulted loans ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers .
the traunches are the mortage brokers or the investers ( mbs ) ?
welcome back . well , in the last presentation , we described a situation where you had a bunch of borrowers . they needed $ 1 billion collectively , because there 's 1000 of them and they each needed $ 1 million to buy their house . and they borrowed the money essentially from a special purpose entity . they borrowed ...
he 'd be willing to take a lower return as long as he was allowed to invest in less risky investments . maybe by law , maybe he 's a pension fund or he 's some type of a mutual fund , that 's forced to invest in something of a certain grade . and say that there 's another investor here , and he thinks that this is bori...
what is a hedge fund ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
well as you may expect , fine grained differences lead to difficulties on the receiving end . and with electrical systems , the resolution of these differences is always limited by electrical noise . if we attach a probe to any electrical line , and zoom in closely enough , we will always find minute undesired currents...
even without electrical noise , would n't a message with over a million possible signals be very difficult to translate into plain english ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
if we attach a probe to any electrical line , and zoom in closely enough , we will always find minute undesired currents . this is an unavoidable result of natural processes such as heat or geomagnetic storms and even latent effects of the big bang . so the differences between signaling events must be great enough that...
what are the `` late effects of the big bang '' ( if i have written the phrase down correctly ) and how do they distort the message received ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
well as you may expect , fine grained differences lead to difficulties on the receiving end . and with electrical systems , the resolution of these differences is always limited by electrical noise . if we attach a probe to any electrical line , and zoom in closely enough , we will always find minute undesired currents...
what is considered an acceptable amount of background noise for a commonly used cable ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
and this simple yet elegant idea forms the basis for how information will be later defined . and this is the final step that brings us to modern information theory . it emerges in the early 20th century .
is shielding on the cables allow us to squeeze more channels onto the cable by lowering the range of `` no mans land '' we need to put between varying channels ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
for example , hard , medium versus soft plucks or high-pitch versus low-pitch plucks by tightening the cable different amounts . this was an idea implemented by thomas edison , which he applied to the morse code system , and it was based on the idea that you could use weak and strong batteries to produce signals of dif...
why do computer only use 1s and 0s ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
so he had plus three volts , plus one volt , minus one volt , and minus three volt . four different current values which could be exchanged . it enabled western union to save money by greatly increasing the number of messages the company could send without building new lines .
would n't a system with three of four different values be more efficient ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
and with three plucks , this jumps to one of 27 messages . now if , instead , alice and bob were exchanging written notes in class , which contain only two letters on a piece of paper , then a single note would contain one of 26 to the power of two , or 676 possible messages . it 's important to realize now that we no ...
would it be possible to calculate the channel capacity of spoken words ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
and after n symbols , we have a tree with s to the power of n leaves . and since each path through this tree can represent a message , we can think of the number of leaves as the size of the message space . this is easy to visualize .
then what is the difference between capacity and message space ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
and after n symbols , we have a tree with s to the power of n leaves . and since each path through this tree can represent a message , we can think of the number of leaves as the size of the message space . this is easy to visualize .
so to send a 50 character message in english , it would require a message space of 26^50 ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
and after n symbols , we have a tree with s to the power of n leaves . and since each path through this tree can represent a message , we can think of the number of leaves as the size of the message space . this is easy to visualize .
what is the message space capacity of a modern computer ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
the message space is simply the width of the base of one of these trees . and it defines the total number of possible messages one could send given a sequence of n symbols . for example , let 's say alice sends bob a message which consists of two plucks and they are using a hard versus soft pluck as their communication...
ok , i want to check my understanding here , the variation in currents allows you to send multiple messages simultaneously over the same right ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
and after n symbols , we have a tree with s to the power of n leaves . and since each path through this tree can represent a message , we can think of the number of leaves as the size of the message space . this is easy to visualize .
also , can someone please clarify the term message space ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
if we attach a probe to any electrical line , and zoom in closely enough , we will always find minute undesired currents . this is an unavoidable result of natural processes such as heat or geomagnetic storms and even latent effects of the big bang . so the differences between signaling events must be great enough that...
what does brit mean by `` the big bang '' ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
how many symbols can we select from at each point ? and we can call this s. and as we 've seen before , these parameters can be thought of as a decision tree of possibilities because each symbol can be thought of as a decision where the number of branches depend on the number of differences . and after n symbols , we h...
what is decision tree of possibility ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
how did edison 's system with more difference increase the speed ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
if all the letters and necessary symbols are options , how does making more options increase the speed ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
clearly now we can step back and begin to define the capacity of a communication system using these two very simple ideas . first , how many symbol transfers per second ? which we called symbol rate .
then in what follows a message seems to be defined implicitly as what can be transmitted in 1 second ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events .
what are the waves on the graph ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
he also used two directions , as gauss and weber did , forward versus reverse current and two intensities . so he had plus three volts , plus one volt , minus one volt , and minus three volt . four different current values which could be exchanged .
can one wire hold more than one pulse at the same time ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faster . for example , hard , medium versus soft plucks or high-pitch versus low-pitch plucks by tightening the cable different amounts . this was an idea implemented by ...
also the difference of symbols is technically infinite , because you can just add more plucks ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
and today it 's known simply as baud , for émile baudot . and we can define this as n where it 's n symbol transfers per second . and number two , how many differences per symbol ?
why could n't alice bring a telegraph to the world of cavemen ?
: it also became clear that there was one other way to increase the capacity of a communication system . we can increase the number of different signaling events . for example , with alice and bob 's string communication system , they soon found that varying the type of plucks allowed them to send their messages faste...
but again , as we expanded the number of different signaling events , we ran into another problem . for example , why not send a thousand or a million different voltage levels per pulse ? well as you may expect , fine grained differences lead to difficulties on the receiving end .
would n't it be hard to receive 1 000 000 different voltage levels ?
given the polynomial above , what are its zeros ? so the zeros of this polynomial are going to be the x-values that make it equal to zero . so it 's going to be the x-values that make this expression equal to zero . or you could say the x-values that satisfy this equation . because if you satisfy this equation , you '...
given the polynomial above , what are its zeros ? so the zeros of this polynomial are going to be the x-values that make it equal to zero .
on 5 what does it mean when they say the zeros of the polynomial factors ?
so i 've said that if you have a vector field , a two-dimensional vector field with component functions p and q , that the divergence of this guy , the divergence of v , which is a scalar-valued function of x and y , is by definition , the partial derivative of p , with respect to x , plus the partial derivative of q ...
so i 've said that if you have a vector field , a two-dimensional vector field with component functions p and q , that the divergence of this guy , the divergence of v , which is a scalar-valued function of x and y , is by definition , the partial derivative of p , with respect to x , plus the partial derivative of q ...
is n't it strange that the formula for divergence is the same as the formula for the directional derivative ?
so i 've said that if you have a vector field , a two-dimensional vector field with component functions p and q , that the divergence of this guy , the divergence of v , which is a scalar-valued function of x and y , is by definition , the partial derivative of p , with respect to x , plus the partial derivative of q ...
if we have something that , let 's see , something that 's a vector-valued function , and it 's gon na be a three-dimensional vector field . so , it 's got x , y , and z as its inputs , and its output then also has to have three dimensions . so , it might be like , p , q , and r , and all of these are functions of x an...
if the input and output have different dimensions , could you just think of the term at the mismatched dimension ( s ) to be zero in the respective set for the dot product and just have that dimension not weigh in on the divergence ?
the purpose of this video is to give you an idea how to approach reading and answering questions on the critical analysis and reasoning skills section . the name of this example passage is physical education in the uk . i 'm going to read through the passage first . when i notice important sentences or signal words , ...
option a is talking about re-stating an objection against compulsory pe . so for a couple of reasons , option b is the better answer . question four , the author 's central theme for the whole passage is a , opposing formal educational mandates , b , describing the consequences of making pe compulsory , c , presenting ...
what does `` sports aptitude made in rebuttal '' mean in option b ?
the purpose of this video is to give you an idea how to approach reading and answering questions on the critical analysis and reasoning skills section . the name of this example passage is physical education in the uk . i 'm going to read through the passage first . when i notice important sentences or signal words , ...
so for a couple of reasons , option b is the better answer . question four , the author 's central theme for the whole passage is a , opposing formal educational mandates , b , describing the consequences of making pe compulsory , c , presenting reasons why pe should not be compulsory , d , advocating that pe be abolis...
why is the answer for the last question not d , that pe should be abolished in schools ?
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package . in duluth , toothpaste costs $ 1.95 a tube while in new york city it costs $ 5.25 a tube . the data for this can be encoded in t...
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package .
what are some real life applications of matrices ?
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package . in duluth , toothpaste costs $ 1.95 a tube while in new york city it costs $ 5.25 a tube . the data for this can be encoded in t...
that 's how they have set-up the data right over here . which statements are true about the above matrix ? select all that apply .
what 's the difference between a matrix and just an ordinary chart ?
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package . in duluth , toothpaste costs $ 1.95 a tube while in new york city it costs $ 5.25 a tube . the data for this can be encoded in t...
select all that apply . the following matrix can also be used to contain the same information as g. that 's what 's interesting about the matrix , what we have right over here is essentially an encapsulation of all of the data that we have in this upper paragraph and it 's useful because a computer could make use of th...
if matrices are used to represent data for a computer , are matrices a relatively new concept or did they exist even before computers were invented ?
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package . in duluth , toothpaste costs $ 1.95 a tube while in new york city it costs $ 5.25 a tube . the data for this can be encoded in t...
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package .
how do matrices have anything to do with linear equations ?
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package . in duluth , toothpaste costs $ 1.95 a tube while in new york city it costs $ 5.25 a tube . the data for this can be encoded in t...
that 's how they have set-up the data right over here . which statements are true about the above matrix ? select all that apply .
why cant we just solve the matrix as an equation ?
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package . in duluth , toothpaste costs $ 1.95 a tube while in new york city it costs $ 5.25 a tube . the data for this can be encoded in t...
that 's how they have set-up the data right over here . which statements are true about the above matrix ? select all that apply .
does the apostrophe next to the g on the changed matrix represent an alteration on the original matrix ?
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package . in duluth , toothpaste costs $ 1.95 a tube while in new york city it costs $ 5.25 a tube . the data for this can be encoded in t...
let 's go there , second row so this is one , two , second row , first column is right over there . g two comma one is not 5.25 , so i would n't check that one either . a change in the price of toilet paper in duluth can be represented by the matrix . toilet paper in duluth is this entry of our matrix right over there ...
in the first statement , why coud n't a city have been represented as a diagonal line ( a cross ) through the matrix ?
: the price of things at two supermarkets are different in different cities . toilet paper in duluth , minnesota cost 3.99 a package while toilet paper in new york city cost 8.95 a package . in duluth , toothpaste costs $ 1.95 a tube while in new york city it costs $ 5.25 a tube . the data for this can be encoded in t...
you could have done something like this toothpaste in new york city was 5.25 , toilet paper in new york city is 8.95 , toothpaste in duluth is 1.95 and toilet paper in duluth is 3.99 . this would have been , this matrix a that i 've just constructed , this does contain the same data because if we appropriately define o...
how do you define what rows and columns represent ?