I've had my Ph.D. for more than twenty five years. One of the most common questions people ask is, "what's the coolest thing you've learned as a scientist?" Well my little plebes, I've decided to pen a list of the ten coolest things I know.
10) Quantum physics still feels to me like there's more to be understood on a deeper level. That being said, particles really aren't solid but "fuzzy" in their behavior (wave-like in certain conditions, point-like in others, depending on scale).
9) Particular to nuclear physics, you can read the age of the earth in the abundance of different radioactive materials in the crust. That was striking to me. It wasn't the original way scientists inferred the age of the earth. It took modern mining and radiometry to provide that confirmation of geologic theory. It’s really satisfying when independent facts come together to form a consistent picture. That’s when you know you’re really on to something.
8) Relativity works. If you accelerate a particle to near the speed of light, its mass and energy really do scale as Einstein predicted. Short-lived particles really do appear to live longer when moving at near the speed of light.
7) Magnetism and magnetic fields aren't real. They're a logical consequence of electrostatics and special relativity because of the moving charges.
6) I have it on good authority (one experiment), that antimatter falls up. So if half the universe turns out to be made of antimatter, it’s still not going to fall towards us.
5) Half of all nuclear power in the US. 10% of the energy market is fueled by re-purposed nuclear missiles once aimed at us.
4) We actually got a positive signal of microbial life on Mars the very first time we looked (Viking II back in 1976). NASA basically refused to believe it could be that easy. The experiment's designer still stands by the results.
3) The long-finned pilot whale has nearly twice as many neurons in it's cerebral cortex than humans (21 b vs. 37 b).
2) Worldwide childhood mortality has been halved since 1990.
1) One scientist - Norman Borlaug is said to have saved more lives (from starvation, up to a billion) than those take by every despot we have numbers for.
Have you ever been at a dinner party and someone said “I wish I knew a good analogy describing how electricity flows through wires?” Yeah, me either. But if you ever find yourself in this pesky situation, here’s an article from Ask Dr. Ben.
Electrical flow is almost completely analogous to water flowing in a pipe. Pressure is Voltage, current is flow (volume of water, or charge, per second) and resistance is effectively the size of the pipe.
A high voltage (pressure) in a big pipe (low resistance) yields a whole lot of flow. Conversely, low voltage in a clogged pipe gets you a trickle. To address wattage (Power = Current x Voltage, after all), just imagine asking how quickly you could pick up a car with a hydraulic piston. More voltage (pressure) and current means you’ll flood the hydraulic chamber and lift the piston faster.
This of course assumes DC (“direct current”, or constant voltage), but alternating current (AC) doesn't strain the analogy either. Just imagine a piston/plunger going back and forth in a closed volume. It sucks and blows back and forth but there is definite flow. And flow can do work, even if it needs a check valve or two to push in one direction. Either way, a high resistance restricts how much water you can move.
Basic circuit elements are easily modeled too. A capacitor is little more than a tank. A resistor is just a small diameter pipe stuck in line with a larger set of plumbing. A transistor is a pressure switch. An inductor coil is like a little turbine inside the pipe (resists when “spinning up”, but then tries to maintain current flow when being turned off). And yes, a diode is a “check valve”, both are just one-way gates to flow.
There’s actually a branch of engineering called Fluidics which leverages this similarity: https://en.wikipedia.org/wiki/Fluidics
It seems like in the 50’s and 60’s, “gee whiz” science and technology books and shows abounded. Now, it seems like it’s become trite to most people, old and young. I’d like to reverse that trend in whatever way I can. Technical skills matter. Zeal for science and general understanding of the universe matter. If we lose sight of that as a society, then WE will fail to matter.