One notable point I forgot to add to the post: G. I. Taylor was not merely a random British physicist reading a magazine with the pictures. He not only worked on the Manhattan Project, but was one of the ~10 scientists actually present at the Trinity test itself. So while this is presented as him being clever and working things out from first principles, in fact the "knew" the answer already, and then figured out how to back into it from open sources to publicize what the yield was without breaking classification.
...I guess that does undermine the point somewhat, oh well.
Δ = sqrt(2Q/λ). - i still don't fully understand this λ term in this, if the orderbook ask is lets say 100Q @ $100, 150 @ $110 and 210 @ $120. What is the λ term for the price impact of 1,000Q units, is it correct to say its sqrt(2*1000/210) = 3.08? what am i doing wrong?
Any good physicist will tell you that the speed of light in a vacuum is c = 1
This was a great read! Brings back fond memories; I recall thinking this was magick when I first sat through a lecture in which the professor applied dimensional analysis to another one of our favourite gadgets, the harmonic oscillator.
It’s not clear to me that % is a unit that can be dimensional-analysised in the equation; a priori I would have said it’s a dimensionless quantity. Perhaps it’s a stand-in for “return, cost or risk per invested capital” but this is still units [$/$]: dimensionless.
The way the G. I. Taylor story was told to our class was that, such was his accuracy in estimating the power of the device, he was suspected of being a security risk and counterintelligence officials were sent to find him in Cambridge, ironically when some of the Cambridge Five spy ring were nearby at the time. (I have no idea if the years even match up - the story has likely been embellished over the years.)
One notable point I forgot to add to the post: G. I. Taylor was not merely a random British physicist reading a magazine with the pictures. He not only worked on the Manhattan Project, but was one of the ~10 scientists actually present at the Trinity test itself. So while this is presented as him being clever and working things out from first principles, in fact the "knew" the answer already, and then figured out how to back into it from open sources to publicize what the yield was without breaking classification.
...I guess that does undermine the point somewhat, oh well.
Great post, brings back memories of physics classes!
What are the good papers on the impact to follow further pls?
Δ = sqrt(2Q/λ). - i still don't fully understand this λ term in this, if the orderbook ask is lets say 100Q @ $100, 150 @ $110 and 210 @ $120. What is the λ term for the price impact of 1,000Q units, is it correct to say its sqrt(2*1000/210) = 3.08? what am i doing wrong?
Any good physicist will tell you that the speed of light in a vacuum is c = 1
This was a great read! Brings back fond memories; I recall thinking this was magick when I first sat through a lecture in which the professor applied dimensional analysis to another one of our favourite gadgets, the harmonic oscillator.
It’s not clear to me that % is a unit that can be dimensional-analysised in the equation; a priori I would have said it’s a dimensionless quantity. Perhaps it’s a stand-in for “return, cost or risk per invested capital” but this is still units [$/$]: dimensionless.
The way the G. I. Taylor story was told to our class was that, such was his accuracy in estimating the power of the device, he was suspected of being a security risk and counterintelligence officials were sent to find him in Cambridge, ironically when some of the Cambridge Five spy ring were nearby at the time. (I have no idea if the years even match up - the story has likely been embellished over the years.)