I guess oil is repelled by water, so when it's poured on top of water it's more like floating on top. So the water pushes up, gravity pulls down and the oil molecules pull on each-other, there is no horizontal friction, allowing the oil to spread out this way. Whereas the oil does slightly stick to your plate, as can be observed when moving the plate around, so it won't spread as thinly?
There’s a couple of possible reasons. First, you probably spilled more oil onto the plate. In the experiment, 0.81 milliliters of oil spread out until it covered a circle with diameter 84 cm. Most spills would be more than a mL of oil, and most plates are much smaller.
Second, most plates aren’t flat. If you have an area of the plate that is at a lower elevation than the rest, the oil would pool up in that area.
Third, even if you fill the plate with water, you could have elevation changes due to surface tension of the water. If the water is concave up, the oil would float upward and form a ring around the edge. If the water is above the surface of the plate, held in just by surface tension, the oil would float upwards and form a bubble at the center of the plate.
Fourth, you could have something else on the plate that acts as an emulsifier. Whether a bit of egg, some pasta water, leftover detergent, these would break up the oil and prevent a film from forming.
The easiest way to have a flat surface is to do the experiment in the center of a much larger body of water, since any effects from the surface tension would be at the edge.
I believe this is at least part of the explanation. Although there might have been some further developments in the 100 years since this was published
Oleic acid on water forms a film one
molecule deep, in which the hydrocarbon chains stand vertically on the water surface
with the COOH groups in contact with the water.
Acetic acid is readily soluble in water because the COOH group has a strong
secondary valence by which it combines with water. Oleic acid is not soluble because
the affinity of the hydrocarbon chains for water is less than their affinity for each other.
When oleic acid is placed on water the acid spreads upon the water because by so doing
the COOH can dissolve in the water without separating the hydrocarbon chains from
each other.
When the surface on which the acid spreads is sufficiently large the double bond
in the hydrocarbon chain is also drawn down on to the water surface, so that the area
occupied is much greater than in the case of the saturated fatty acids.
Oils which do not contain active groups, as for example pure paraffin oil, do not
spread upon the surface of water
"Asimov was so prolific and diverse in his writing that his books span all major categories of the Dewey Decimal Classification except for category 100, philosophy and psychology" - from his Wikipedia page.
He was also incredibly talented in phrasing ideas so that they stick in the reader's mind. I am right now sitting next to a dog Asimov named after him.
My Simpsons memory of him is him coming up from the clouds as Mustafa, Darth Vader, and himself saying "This is CNN". But TIL it wasn't him but Harry Shearer doing an impression.
How does it know how many times it needs to shoot the zombie before it dies?
Most enemies have enough hit points to survive the first shot. If the model is only trained on the previous frame, it doesn't know how many times the enemy was already shot at.
From the video it seems like it is probability based - they may die right away or it might take way longer than it should.
I love how the player's health goes down when he stands in the radioactive green water.
In Doom the enemies fight with each other if they accidentally incur "friendly fire". It would be interesting to see it play out in this version.
> I love how the player's health goes down when he stands in the radioactive green water.
This is one of the bits that was weird to me, it doesn't work correctly. In the real game you take damage at a consistent rate, in the video the player doesn't and whether the player takes damage or not seems highly dependent on some factor that isn't whether or not the player is in the radioactive slime. My thought is that its learnt something else that correlates poorly.
> In Doom the enemies fight with each other if they accidentally incur "friendly fire". It would be interesting to see it play out in this version.
They trained this thing on bot gameplay, so I bet it does poorly when advanced strategies like deliberately inducing mob infighting are employed (the bots probably didn't do that a lot, of at all.)
The book Permutation City explores some concepts of immortality that would be immune to the heat death of the universe.
In the book consciousness does not have to be chronological in time or on any specific biological or synthetic hardware. It just has to be encoded in a physical state somewhere, and the next state can be anywhere else in time or space.
One example is a person who deliberately set their consciousness on a loop, doing his favorite activity, climbing a skyscraper too tall to see the bottom or the top. Permanent flow state, not quite sure how long he has been climbing, feeling an adrenaline high.
It may seem like a boring life, but for that person it's indistinguishable from a normal life that happens to be doing that action in the moment.
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