Something Deeply Hidden - Quantum Worlds and the Emergence of Spacetime


How much do I want to read more? 8/10

Fascinating. Just as quantum physic is. The author tackle the subject with care and clarity. We can feel his concern about the importance of the subject.
This new system being the key to understand not only the inffinetesimal but also the black holes and the whole universe.
He's concerned about the fact that modern physists only apply it without understanding how it actually works.


PROLOGUE - Don’t Be Afraid

Quantum mechanics is our best theory of the microscopic world. It describes how atoms and particles interact through the forces of nature, and makes incredibly precise experimental predictions.

Quantum mechanics is ubiquitous in modern technology. Semiconductors, transistors, microchips, lasers, and computer memory all rely on quantum mechanics to function. For that matter, quantum mechanics is necessary to make sense of the most basic features of the world around us. Essentially all of chemistry is a matter of applied quantum mechanics. To understand how the sun shines, or why tables are solid, you need quantum mechanics.

Imagine closing your eyes. Hopefully things look pretty dark.
If our eyes were as sensitive to infrared light as they are to visible light, we would be blinded even when our lids were closed, from all the light emitted by our eyeballs themselves. But the rods and cones that act as light receptors in our eyes are cleverly sensitive to visible light, not infrared. How do they manage that? Ultimately, the answer comes down to quantum mechanics.

Quantum mechanics isn’t magic. It is the deepest, most comprehensive view of reality we have.
The development of quantum mechanics in the early years of the twentieth century, involving names like Planck, Einstein, Bohr, Heisenberg, Schrödinger, and Dirac, left us by 1927 with a mature understanding that is surely one of the greatest intellectual accomplishments in human history.

On the other hand, in the memorable words of Richard Feynman, “I think I can safely say that nobody understands quantum mechanics.” We use quantum mechanics to design new technologies and predict the outcomes of experiments. But honest physicists admit that we don’t truly understand quantum mechanics.
We have a recipe that we can safely apply in certain prescribed situations, and which returns mind-bogglingly precise predictions.
But if you want to dig deeper and ask what is really going on, we simply don’t know.

extra rules tell us what happens when we observe a quantum system, and that behavior is completely different from how the system behaves when we’re not observing it. What in the world is going on with that?
shifting from a view where the world exists objectively and independently of how we perceive it, to one where the act of observation is somehow fundamental to the nature of reality.

This book has three main messages.

  1. quantum mechanics should be understandable. such understanding should be a high-priority goal of modern science. Quantum mechanics is unique among physical theories in drawing an apparent distinction between what we see and what really is.
  2. we have made real progress toward understanding.
  3. all this matters, and not just for the integrity of science. the nature of spacetime. the origin and ultimate fate of the entire universe.

Part One - Spooky

1 - What’s Going On - Looking at the Quantum World

Albert Einstein stuck quantum mechanics with the label "spukhaft" (“spooky.”) a part of physics that is unavoidably mystifying, weird, bizarre, unknowable, strange, baffling. Spooky.
A brief search for books with “quantum” in the title:

It is not only relevant to microscopic processes. It describes the whole world, from you and me to stars and galaxies, from the centers of black holes to the beginning of the universe. But it is only when we look at the world in extreme close-up that the apparent weirdness of quantum phenomena becomes unavoidable.

I want to present quantum mechanics in a way that will make it maximally understandable right from the start. It will still seem strange, but that’s the nature of the beast.