James Hartle - What is Quantum Cosmology?

“Quantum” is the theory of the utterly small. “Cosmology” is the study of the utterly large. They combine, remarkably, when in the very early universe the entire universe was far smaller than the smallest particle. What does it mean to describe the universe as a ‘quantum wave function’? What are the quantum features of space and time?



James B. Hartle is Research Professor and Emeritus Professor of Physics at the University of California, Santa Barbara.


Closer to Truth presents the world’s greatest thinkers exploring humanity’s deepest questions. Discover fundamental issues of existence. Engage new and diverse ways of thinking. Appreciate intense debates. Share your own opinions. Seek your own answers.

[haley-and_gaming]

The background setting is absolutely beautiful.

[rishabhaniket]

Rest in peace gou beautiful and curious spirit. Your time in this universe was well spent.

[GlossRabban]

Look at that background. I want to paint those happy little Trees. 😁

[restinaaprilianti]

Beautiful scenery in the background 😍😍😍

[SantiagoRK]

For a moment I thought he was Bernie Sanders lol

[tonyaustin]

I needed illustrations to understand this but it still very good and informative.

[brydonjesse]

So I feel we can show the universe as a structure we can see as a whole at once. We could see how fast it "moves" based on movements and space time on our scale. What is it doing and what does it look like to a outside observer

[chrisgreen]

Pick a nice spot to do your video...
Good advice for any YouTuber

[holgerjrgensen]

Every one know what time-space is,
No one can explain what 'space-time' is,
few understand the importance of the perspective-principle, and the wave-principle in macro-scale.

[julianmann]

This is a fascinating and original idea, however I am not sure it can be correct. At the Quantum level, the Wave Function is only necessary to describe the behaviour of quantum particles. At the classical level of Newton/Einstein we don't need it at all in classical physics and mechanics. The explanation for bizarre behaviour at the quantum level
is readily provided by Backward Time

[jasonemryss]

Why are presumptive ideations acknowledged as fact on closer to truth? They should call the show "Closer to Kuhn"

[aclearlight]

I know Dr. Hartle is a great scientist (I even took a course from him once), but somehow his answers/assertions here leave me feeling a bit dissatisfied. Without knowing the size and shape of the universe, and the nature of dark matter, for example, how can we specify the boundary conditions necessary for constructing a realistic Hamiltonian? That issue aside, how could we ever actually solve for "the" wavefunction, at any specified level of graining, given that we still lack a working theory of quantum gravity?

[musicaangomera]

And this is the closest explanation of quantum gravity I have heard.

[tomburns]

Does anyone see anything wrong with someone who watches a video about Quantum Mechanics & comments on THE BEAUTY OF THE SCENERY. We're LOST. BESIDES I'M LOSING FAITH IN PHYSICISTS, THEIR THEORIES (GUESSING) AND MOST THAT I'VE SEEN HERE

[Warguard]

The eigenstate of the universe...works for me!

[josephtanas]

James hartle what is the theory that our universe is just a quantum universe of another reality..or physical universe. Is this a new theory in my understanding.

[donemigholzjr.]

. . . . . . . . Why in the world do people that know some of what this discussion is about do not believe in relativity? It is like Einstein has not been proven wrong but everyone assumes he is or will be wrong.

[danielmoktar]

Intellectuals: *speaking*
Chair: *squeks uncrontrollably*

[willmosse]

I have to say I struggle with understanding how one equation can encompass everything...

[ik]

"There is nothing outside this Universe" - that is a huge assumption that has not been verified.