Videos in: 2020

Computation All the Way Down

[6.19.20]

We're now in this situation where people just assume that science can compute everything, that if we have all the right input data and we have the right models, science will figure it out. If we learn that our universe is fundamentally computational, that throws us right into the idea that computation is a paradigm you have to care about. The big transition was from using equations to describe how everything works to using programs and computation to describe how things work. And that's a transition that's happened after 300 years of equations. The transition time to using programs has been remarkably quick, a decade or two. One area that was a holdout, despite the transition of many fields of science into the computational models direction, was fundamental physics.

If we can firmly establish this fundamental theory of physics, we know it's computation all the way down. Once we know it's computation all the way down, we're forced to think about it computationally. One of the consequences of thinking about things computationally is this phenomenon of computational irreducibility. You can't get around it. That means we have always had the point of view that science will eventually figure out everything, but computational irreducibility says that can't work. It says even if we know the rules for system, it may be the case that we can't work out what that system will do any more efficiently than basically just running the system and seeing what happens, just doing the experiment so to speak. We can't have a predictive theoretical science of what's going to happen.

STEPHEN WOLFRAM is a scientist, inventor, and the founder and CEO of Wolfram Research. He is the creator of the symbolic computation program Mathematica and its programming language, Wolfram Language, as well as the knowledge engine Wolfram|Alpha. He is also the author, most recently, of A Project to Find the Fundamental Theory of Physics. Stephen Wolfram's Edge Bio Page

 


Go to stand-alone video: :
 

How Humans Make the Earth Their Home

[6.12.20]

Beginning in 2012, and for many summers ever since, my team and I have been helicoptering onto the Greenland ice sheet, in this fantastical melt zone. We use helicopters to string cableways over the top of rushing super glacial rivers so that we can hang this river discharge measurement technology called Acoustic Doppler Current Profiler (ADCP). We operate around the clock to collect measurements of river discharge every hour, for up to a week in duration. We have collected the world's first meltwater runoff measurements on top of the ice sheet. What we then do is simultaneously use drones and satellites to map out the upstream contributing watershed area flowing to that point where we are collecting the discharge measurements. When we know the contributing watershed area and we have the flow measurements at the bottom of the watershed, we then have a completely independent field dataset from which we can test the ability of climate models to simulate meltwater runoff from the Greenland ice sheet. And it's those models that are being used to predict the future. It's those models that are being used to estimate projected ranges of sea level rise in IPCC reports and so forth.

LAURENCE C. SMITH is the John Atwater and Diana Nelson University Professor of Environmental Studies and Professor of Earth, Environmental and Planetary Sciences at Brown University. He is the author, most recently, of Rivers of PowerLaurence C. Smith's Edge Bio Page


Go to stand-alone video: :
 

We Have the Power to Destroy Ourselves Without the Wisdom to Ensure That We Don't

[4.6.20]

I've been thinking about just how bright our future could be, how science knows almost no limits to what we could achieve, to the durations that we could last, to the portion of the cosmos that we could discover and explore, and to the heights of quality in each of our lives or the types of achievements we could make. . . . It's this vision of this wonderful and vast future that's at stake that inspires me to think more carefully about the risks we face now and the ways that we might imperil all of this with our actions. What things can only our generation or our children's generation do in order to protect this seed of humanity so that we can grow into something even more amazing, to protect our present and thereby protect our future?

TOBY ORD is a senior research fellow in philosophy at Oxford University and author of The Precipice: Existential Risk and the Future of HumanityToby Ord's Edge Bio Page


 

Realism Is False

[1.27.20]

. . . I want to propose that realism is false, and what we're seeing is more like a user interface or a virtual reality headset. Think about a virtual reality game of tennis. You're playing VR tennis with a friend, you both have your headset and body suits on, you see your friend's avatar on a tennis court and you start playing. Your friend hits the tennis ball to you, and you hit the same tennis ball back to your friend, but is your friend seeing exactly the same tennis ball that you're seeing? Well, of course not. There's no public tennis ball. You have some photons being sprayed to your eye by your headset, and those photons are causing your visual system to create your own perception of what you would call a green tennis ball. Your friend has a headset on, which is spraying photons to his eye, and his visual system is creating his own green tennis ball perception.

It turns out that both of those perceptions are coordinated by something else, namely a supercomputer that's sending the photons to both headsets, causing both headsets to work in coordination. . . .

All the things that we would do to say that objects really exist even when they're not perceived hold here in virtual reality. . . . That doesn't mean that the tennis ball exists and has any physical properties when it's not perceived; it just means that there is some objective reality.

DONALD D. HOFFMAN is a full professor of cognitive science at the University of California, Irvine. He is the author, most recently, of The Case Against Reality: Why Evolution Hid the Truth from Our EyesDonald D. Hoffman's Edge Bio Page

 


Go to stand-alone video: :