My first job out of college was as an academic researcher at one of the largest juvenile detention centers in the country.
And every day I would drive to this building on the West Side of Chicago, go through the security checkpoint and walk down these brown, brick hallways as I made my way down to the basement to observe the intake process.
The kids coming in were about 10 to 16 years old, usually always black and brown, most likely from the same impoverished South and West Sides of Chicago.
They should've been in fifth to tenth grade, but instead they were here for weeks on end awaiting trial for various crimes.
Some of them came back to the facility 14 times before their 15th birthday.
And as I sat there on the other side of the glass from them, idealistic with a college degree, I wondered to myself: Why didn't schools do something more to prevent this from happening?
It's been about 10 years since then, and I still think about how some kids get tracked towards college and others towards detention, but I no longer think about schools' abilities to solve these things.
You see, I've learned that so much of this problem is systemic that often our school system perpetuates the social divide.
It makes worse what it's supposed to fix.
That's as crazy or controversial as saying that our health care system isn't preventative but somehow profits off of keeping us sick ...
oops.
(Laughter) I truly do believe though that kids can achieve great things despite the odds against them, and in fact, my own research shows that.
But if we're serious about helping more kids from across the board to achieve and make it in this world, we're going to have to realize that our gaps in student outcomes are not so much about achievement as much as they are about opportunity.
A 2019 EdBuild report showed that majority-white districts receive about 23 billion dollars more in annual funding than nonwhite districts, even though they serve about the same number of students.
Lower resource schools are dealing with lower quality equipment, obsolete technology and paying teachers way less.
Here in New York, those are also the schools most likely to serve the one in 10 elementary school students who will most likely have to sleep in a homeless shelter tonight.
The student, parent and teacher are dealing with a lot.
Sometimes places are misplacing the blame back on them.
In Atlanta, we saw that teachers felt desperate enough to have to help their students cheat on standardized tests that would impact their funding.
Eight of them went to jail for that in 2015 with some sentences as high as 20 years, which is more than what many states give for second-degree murder.
The thing is though, in places like Tulsa, teachers' pay has been so bad that these people have had to go to food pantries or soup kitchens just to feed themselves.
The same system will criminalize a parent who will use a relative's address to send their child to a better school, but for who knows how long authorities have turned a blind eye to those who can bribe their way onto the most elite and beautiful college campuses.
And a lot of this feels pretty heavy to be saying -- and maybe to be hearing -- and since there's nothing quite like economics talk to lighten the mood -- that's right, right?
Let me tell you about some of the costs when we fail to tap into our students' potential.
A McKinsey study showed that if in 1998 we could've closed our long-standing student achievement gaps between students of different ethnic backgrounds or students of different income levels, by 2008, our GDP -- our untapped economic gains -- could have gone up by more than 500 billion dollars.
Those same gaps in 2008, between our students here in the US and those across the world, may have deprived our economy of up to 2.3 trillion dollars of economic output.
But beyond economics, numbers and figures, I think there's a simpler reason that this matters, a simpler reason for fixing our system.
It's that in a true democracy, like the one we pride ourselves on having -- and sometimes rightfully so -- a child's future should not be predetermined by the circumstances of their birth.
A public education system should not create a wider bottom and more narrow top.
Some of us can sometimes think that these things aren't that close to home, but they are if we broaden our view, because a leaky faucet in our kitchen, broken radiator in our hallway, those parts of the house that we always say we're going to get to next week, they're devaluing our whole property.
Instead of constantly looking away to solutions like privatization or the charter school movement to solve our problems, why don't we take a deeper look at public education, try to take more pride in it and maybe use it to solve some of our social problems.
Why don't we try to reclaim the promise of public education and remember that it's our greatest collective responsibility?
Luckily some of our communities are doing just that.
The huge teacher strikes in the spring of 2019 in Denver and LA -- they were successful because of community support for things like smaller class sizes and getting things into schools like more counselors in addition to teacher pay.
And sometimes for the student, innovation is just daring to implement common sense.
In Baltimore a few years ago, they enacted a free breakfast and lunch program, taking away the stigma of poverty and hunger for some students but increasing achievement in attendance for many others.
And in Memphis, the university is recruiting local, passionate high school students and giving them scholarships to go teach in the inner city without the burden of college debt.
And north of here in The Bronx, I recently researched these partnerships being built between high schools, community colleges and local businesses who are creating internships in finance, health care and technology for students without "silver spoon" connections to gain important skills and contribute to the communities that they come from.
So today I don't necessarily have the same questions about education that I did when I was an idealistic, perhaps naïve college grad working in a detention center basement.
It's not: Can schools save more of our students?
Because I think we have the answer to that -- and it's yes they can, if we save our schools first.
We can start by caring about the education of other people's children ...
And I'm saying that as someone who doesn't have kids yet but wants to worry a little bit less about the future when I do.
Cultivating as much talent as possible, getting as many girls as we can from all over into science and engineering, as many boys as we can into teaching -- those are investments for our future.
Our students are like our most valuable resource, and when you put it that way, our teachers are like our modern-day diamond and gold miners, hoping to help make them shine.
Let's contribute our voices, our votes and our support to giving them the resources that they will need not just to survive but hopefully thrive, allowing all of us to do so as well.
Thank you.
(Applause and cheers)
For as far back as we can trace our existence, humans have been fascinated with death and resurrection.
Nearly every religion in the world has some interpretation of them, and from our earliest myths to the latest cinematic blockbusters, the dead keep coming back.
But is resurrection really possible?
And what is the actual difference between a living creature and a dead body, anyway?
To understand what death is, we need to understand what life is.
One ancient theory was an idea called vitalism, which claimed that living things were unique because they were filled with a special substance, or energy, that was the essence of life.
Whether it was called qi, lifeblood, or humors, the belief in such an essence was common throughout the world, and still persists in the stories of creatures who can somehow drain life from others, or some form of magical sources that can replenish it.
Vitalism began to fade in the Western world following the Scientific Revolution in the 17th century.
René Descartes advanced the notion that the human body was essentially no different from any other machine, brought to life by a divinely created soul located in the brain's pineal gland.
And in 1907, Dr. Duncan McDougall even claimed that the soul had mass, weighing patients immediately before and after death in an attempt to prove it.
Though his experiments were discredited, much like the rest of vitalism, traces of his theory still come up in popular culture.
But where do all these discredited theories leave us?
What we now know is that life is not contained in some magical substance or spark, but within the ongoing biological processes themselves.
And to understand these processes, we need to zoom down to the level of our individual cells.
Inside each of these cells, chemical reactions are constantly occurring, powered by the glucose and oxygen that our bodies convert into the energy-carrying molecule known as ATP.
Cells use this energy for everything from repair to growth to reproduction.
Not only does it take a lot of energy to make the necessary molecules, but it takes even more to get them where they need to be.
The universal phenomenon of entropy means that molecules will tend towards diffusing randomly, moving from areas of high concentration to low concentration, or even breaking apart into smaller molecules and atoms.
So cells must constantly keep entropy in check by using energy to maintain their molecules in the very complicated formations necessary for biological functions to occur.
The breaking down of these arrangements when the entire cell succumbs to entropy is what eventually results in death.
This is the reason organisms can't be simply sparked back to life once they've already died.
We can pump air into someone's lungs, but it won't do much good if the many other processes involved in the respiratory cycle are no longer functioning.
Similarly, the electric shock from a defibrillator doesn't jump-start an inanimate heart, but resynchronizes the muscle cells in an abnormally beating heart so they regain their normal rhythm.
This can prevent a person from dying, but it won't raise a dead body, or a monster sewn together from dead bodies.
So it would seem that all our various medical miracles can delay or prevent death but not reverse it.
But that's not as simple as it sounds because constant advancements in technology and medicine have resulted in diagnoses such as coma, describing potentially reversible conditions, under which people would have previously been considered dead.
In the future, the point of no return may be pushed even further.
Some animals are known to extend their lifespans or survive extreme conditions by slowing down their biological processes to the point where they are virtually paused.
And research into cryonics hopes to achieve the same by freezing dying people and reviving them later when newer technology is able to help them.
See, if the cells are frozen, there's very little molecular movement, and diffusion practically stops.
Even if all of a person's cellular processes had already broken down, this could still conceivably be reversed by a swarm of nanobots, moving all the molecules back to their proper positions, and injecting all of the cells with ATP at the same time, presumably causing the body to simply pick up where it left off.
So if we think of life not as some magical spark, but a state of incredibly complex, self-perpetuating organization, death is just the process of increasing entropy that destroys this fragile balance.
And the point at which someone is completely dead turns out not to be a fixed constant, but simply a matter of how much of this entropy we're currently capable of reversing.
Nearly everyone in the world is part of some community, whether large or small.
And all of these communities have similar needs.
They need light, they need heat they need air-conditioning.
People can't function very well when it's too hot or too cold.
They need food to be grown or provided, distributed and stored safely.
They need waste products to be collected, removed and processed.
People in the community need to be able to get from one place to another as quickly as possible.
And a supply of energy is the basis for all of these activities.
Energy in the form of electricity provides light and air-conditioning.
Energy in the form of heat keeps us warm.
And energy in chemical form provides fertilizer; it drives farm machinery and transportation energy.
Now, I spent 10 years scott66@example.net.
In the beginning of my time there in 2000, I was very interested in communities.
But this is the kind of community I was thinking of -- a lunar community It had all of the same needs as a community on Earth would have, but it had some very unique constraints.
And we had to think about how we would provide energy for this very unique community.
There’s no coal on the Moon.
There's no petroleum.
There’s no natural gas.
There's no atmosphere.
There’s no wind, either.
And solar power had a real problem: the Moon orbits the Earth once a month.
For two weeks, the sun goes down, and your solar panels don't make any energy.
If you want to try to store enough energy in batteries for two weeks, it just simply isn't practical.
So nuclear energy was really the only choice.
Now, back in 2000, I didn't really know too much about nuclear power, so I started trying to learn.
Almost all of the nuclear power we use on Earth today uses water as a basic coolant.
This has some advantages, but it has a lot of disadvantages.
If you want to generate electricity, you have to get the water a lot hotter than you normally can.
At normal pressures, water will boil at 100 degrees Celsius.
This isn't nearly hot enough to generate electricity effectively.
So water-cooled reactors have to run at much higher pressures than atmospheric pressure.
Some water-cooled reactors run at over 70 atmospheres of pressure, and others have to run at as much as 150 atmospheres of pressure.
There's no getting around this; it's simply what you have to do if you want to generate electricity using a water-cooled reactor.
This means you have to build a water-cooled reactor as a pressure vessel, with steel walls over 20 centimeters thick.
If that sounds heavy, that's because it is.
Things get a lot worse if you have an accident where you lose pressure inside the reactor.
If you have liquid water at 300 degrees Celsius and suddenly you depressurize it, it doesn't stay liquid for very long; it flashes into steam.
So water-cooled reactors are built inside of big, thick concrete buildings called containment buildings, which are meant to hold all of the steam that would come out of the reactor if you had an accident where you lost pressure.
Steam takes up about 1,000 times more volume than liquid water, so the containment building ends up being very large, relative to the size of the reactor.
Another bad thing happens if you lose pressure and your water flashes to steam.
If you don't get emergency coolant to the fuel in the reactor, it can overheat and melt.
The reactors we have today use uranium oxide as a fuel.
It's a ceramic material similar in performance to the ceramics we use to make coffee cups or cookware or the bricks we use to line fireplaces.
They're chemically stable, but they're not very good at transferring heat.
If you lose pressure, you lose your water, and soon your fuel will melt down and release the radioactive fission products within it.
Making solid nuclear fuel is a complicated and expensive process.
And we extract less than one percent of the energy for the nuclear fuel before it can no longer remain in the reactor.
Water-cooled reactors have another additional challenge: they need to be near large bodies of water, where the steam they generate can be cooled and condensed.
Otherwise, they can't generate electrical power.
Now, there's no lakes or rivers on the Moon, so if all of this makes it sound like water-cooled reactors aren't such a good fit for a lunar community, I would tend to agree with you.
(Laughter) I had the good fortune to learn about a different form of nuclear power that doesn't have all these problems, for a very simple reason: it's not based on water-cooling, and it doesn't use solid fuel.
Surprisingly, it's based on salt.
One day, I was at a friend's office at work, and I noticed this book on the shelf, "Fluid Fuel Reactors."
I was interested and asked him if I could borrow it.
Inside that book, I learned about research in the United States back in the 1950s, into a kind of reactor that wasn't based on solid fuel or on water-cooling.
It didn't have the problems of the water-cooled reactor, and the reason why was pretty neat.
It used a mixture of fluoride salts as a nuclear fuel, specifically, the fluorides of lithium, beryllium, uranium and thorium.
Fluoride salts are remarkably chemically stable.
They do not react with air and water.
You have to heat them up to about 400 degrees Celsius to get them to melt.
But that's actually perfect for trying to generate power in a nuclear reactor.
Here's the real magic: they don't have to operate at high pressure.
And that makes the biggest difference of all.
This means they don't have to be in heavy, thick steel pressure vessels, they don't have to use water for coolant and there's nothing in the reactor that's going to make a big change in density, like water.
So the containment building around the reactor can be much smaller and close-fitting.
Unlike the solid fuels that can melt down if you stop cooling them, these liquid fluoride fuels are already melted, at a much, much lower temperature.
In normal operation, you have a little plug here at the bottom of the reactor vessel.
This plug is made out of a piece of frozen salt that you've kept frozen by blowing cool gas over the outside of the pipe.
If there's an emergency and you lose all the power to your nuclear power plant, the little blower stops blowing, the frozen plug of salt melts, and the liquid fluoride fuel inside the reactor drains out of the vessel, through the line and into another vessel called a drain tank.
Inside the drain tank, it's all configured to maximize the transfer of heat, so as to keep the salt passively cooled as its heat load drops over time.
In water-cooled reactors, you generally have to provide power to the plant to keep the water circulating and to prevent a meltdown, as we saw in Japan.
But in this reactor, if you lose the power to the reactor, it shuts itself down all by itself, without human intervention, and puts itself in a safe and controlled configuration.
Now, this was sounding pretty good to me, and I was excited about the potential of using a liquid fluoride reactor to power a lunar community.
But then I learned about thorium, and the story got even better.
Thorium is a naturally occurring nuclear fuel that is four times more common in the Earth's crust than uranium.
It can be used in liquid fluoride thorium reactors to produce electrical energy, heat and other valuable products.
It's so energy-dense that you could hold a lifetime supply of thorium energy in the palm of your hand.
Thorium is also common on the Moon and easy to find.
Here's an actual map of where the lunar thorium is located.
Thorium has an electromagnetic signature that makes it easy to find, even from a spacecraft.
With the energy generated from a liquid fluoride thorium reactor, we could recycle all of the air, water and waste products within the lunar community.
In fact, doing so would be an absolute requirement for success.
We could grow the crops needed to feed the members of the community even during the two-week lunar night, using light and power from the reactor.
It seemed like the liquid fluoride thorium reactor, or LFTR, could be the power source that could make a self-sustainable lunar colony a reality.
But I had a simple question: If it was such a great thing for a community on the Moon, why not a community on the Earth, a community of the future, self-sustaining and energy-independent?
The same energy generation and recycling techniques that could have a powerful impact on surviving on the Moon could also have a powerful impact on surviving on the Earth.
Right now, we're burning fossil fuels because they're easy to find and because we can.
Unfortunately, they're making some parts of our planet look like the Moon.
Using fossil fuels entangles us in conflict in unstable regions of the world and costs money and lives.
Things could be very different if we were using thorium.
You see, in a LFTR, we could use thorium about 200 times more efficiently than we're using uranium now.
And because the LFTR is capable of almost completely releasing the energy in thorium, this reduces the waste generated over uranium by factors of hundreds, and by factors of millions over fossil fuels.
We're still going to need liquid fuels for vehicles and machinery, but we could generate these liquid fuels from the carbon dioxide in the atmosphere and from water, much like nature does.
We could generate hydrogen by splitting water and combining it with carbon harvested from CO2 in the atmosphere, making fuels like methanol, ammonia, and dimethyl ether, which could be a direct replacement for diesel fuels.
Imagine carbon-neutral gasoline and diesel, sustainable and self-produced.
Do we have enough thorium?
Yes, we do.
In fact, in the United States, we have over 3,200 metric tons of thorium that was stockpiled 50 years ago and is currently buried in a shallow trench in Nevada.
This thorium, if used in LFTRs, could produce almost as much energy as the United States uses in three years.
And thorium is not a rare substance, either.
There are many sites like this one in Idaho, where an area the size of a football field would produce enough thorium each year to power the entire world.
Using liquid fluoride thorium technology, we could move away from expensive and difficult aspects of current water-cooled, solid-fueled uranium nuclear power.
We wouldn't need large, high-pressure nuclear reactors and big containment buildings that they go in.
We wouldn't need large, low-efficiency steam turbines.
We wouldn't need to have as many long-distance power transmission infrastructure, because thorium is a very portable energy source that can be located near to where it is needed.
A liquid fluoride thorium reactor would be a compact facility, very energy-efficient and safe, that would produce the energy we need day and night, and without respect to weather conditions.
In 2007, we used five billion tons of coal, 31 billion barrels of oil and five trillion cubic meters of natural gas, along with 65,000 tons of uranium to produce the world's energy.
With thorium, we could do the same thing with 7,000 tons of thorium that could be mined at a single site.
If all this sounds interesting to you, I invite you to visit our website, where a growing and enthusiastic online community of thorium advocates is working to tell the world about how we can realize a clean, safe and sustainable energy future, based on the energies of thorium.
Thank you very much.
(Applause)